A novel approach for parameters determination in four lumped PV parametric model with operative range evaluations

2013

The paper presents a novel numerical approach for the parameters determination of crystalline silicon PV models four lumped parameters equivalent circuit. The novel approach basically deals with a new method, alternative to the iterative one known in literature, to calculate the series resistance. Particularly, it allows the evaluation of the lumped parameters on the basis of the manufacturer’s datasheet. The new approach has been validated both in the Maximum Power Point (MPP) and close to it by comparing values and curves obtained by means of the model implementation in Matlab/Simulink environment with those related to some five parameters models and manufacturer curves. Results show that…

A Hybrid Energy Storage Sizing for a Vertical Take-off and Landing Electric Aircraft

2021

The energy storage sizing procedure for an all-electric aircraft, characterised by vertical take-off and landing (VTOL), is presented in the paper. In order to define the energy consumption, the propulsion system model has been developed and simulated, referring to a specific configuration of VOLT obtained by the transformation of a very light twin-propeller aircraft named Tecnam P2012 T. Specifically, a flight mission-oriented to air city taxing has been considered. The simulation results highlight the presence of significant peak power during take-off and landing. At the aim of optimising the weight and the volume of the energy storage systems (ESSs), considered a critical issue in all-el…

Uncertainty management in the measurements of low frequency magnetic fields

2014

The paper deals with low-frequency magnetic field measurements carried out by using a broadband and isotropic instrument. These measurements are characterized by very high uncertainty values, which imply a high risk of wrong decisions when there is the need to establish if a site complies or does not comply with specified emission limits. To reduce this risk, we decided to perform the so called “uncertainty management” that is the discipline of optimizing the cost of a measurement versus the uncertainty target. The task is achieved by using the PUMA method that is an iterative technique originally conceived for geometrical and mechanical measurements. The approach is completely based on the…

An efficient wireless power transfer prototype for electrical vehicles

2017

Based on the inductive power transfer (IPT), the contactless approach allows safe and comfortable operations of battery charging for Electric Vehicles (EVs). In this paper, a contactless system particularly suitable for E-bike battery charging is proposed. A practical realization of the system has been carried out, aiming at the system evaluation in terms of working and efficiency. Through a phase shift modulation, a power regulation has been implemented. The target power level is 100 W.

High Performance FOC for Induction Motors with Low Cost ATSAM3X8E Microcontroller

2018

In this paper the Authors present the Arduino Due board application for an induction motor field oriented control (FOC) algorithm. The low cost Arduino Due board is equipped with a ATSAM3X8E microcontroller that performs the algorithm calculation, data processing, current signals and speed/position data acquisition. The control algorithm has been developed with the help of the open source Arduino integrated development environment, whereas a user friendly control interface, used to manage the speed or position set point, has been developed in Java language by means of an other open source software, namely, Processing. An experimental test bed has been set up in order to validate the FOC sys…

Design and experimental characterization of a low-cost, real-time, wireless AC monitoring system based on ATmega 328P-PU microcontroller

2015

This paper describes the development and experimental characterization of a real-time, low-cost, wireless AC monitoring system based on ATmega 328P-PU microcontroller. The proposed system is composed by a main brain for the acquisition and the processing of the data measured by smart meters. From the experimental tests discussed in this work it is demonstrated that the proposed system can monitor, with adequate accuracy, the working cycles of electrical loads in order to evaluate its energy consumption.

High-Speed Machines: Typologies, Standards, and Operation under PWM Supply

2018

This paper presents an overview of the most recent state of the art in the field of high-speed electric machines fed through high-frequency converters. This type of systems is rapidly wide spreading in aeronautical and automotive applications, as well as microturbines. Each typology has its own advantages and downsides, which are analytically presented in this paper. Some types of high-speed electric machines require high-frequency voltage supply, highly stressing the dielectric materials of the winding insulation system. For this reason, in high-speed electric drives, premature failure may occur and a reduction of the total system reliability has been observed in the past years. Such issue…

Energy Management and Smart Grids

2013

The paper outlines energy management concepts and the smart grid evolution. The necessity of considering energy management as a crucial innovation in load supplying to permit a more powerful penetration of renewable energy usage at the building and city level and to perform energy savings and CO2 emissions reduction is pointed out. The driving factors to enhance the current power distribution are presented, and the benefits concerning smart grids are underlined. In the paper, a specific energy management analysis is reported by considering all the electric value chain, and the demand-side management and distributed on site control actions are described. To verify the benefit of energy manag…

Computer-aided analysis and design procedure for rotating induction machine magnetic circuits and windings

2018

The aim of this study is to present a new, accurate, and user-friendly software procedure for the analysis and rapid design of rotating induction machine windings, considering both the electric and the magnetic specifications of the machine itself. This procedure is a valid aid for quick first stage design without the necessity of using finite element method (FEM)-based design procedures. FEM can be used in a second design phase in order to refine the first stage results. The design procedure is hereafter outlined and some examples show its capability.

Experimental Validation of Maximum Constant Boost Control and Switching Frequency Optimal for three-phase Quasi-Z-Source Converters

2020

This paper presents a modified modulation scheme for quasi-Z-Source converters, based on the Maximum Constant Boost Control (MCBC) concept and Switching Frequency Optimal (SFO) as reference signal. The effectiveness of the proposed technique is validated by comparing the obtained results (in terms of AC harmonic content and voltage stress) with those carried out from traditional modulation schemes. For this reason, a test bench has been assembled and the benefits of the SFO MCBC modulation scheme have been valuated.

Ev charging station at university campus

2017

This paper faces the technical and economic challenges related to the design of a green recharge area for electric vehicles at the Campus of Palermo, Italy, with the aim of reduce both costs and pollution connected to the charging process. Based on the behaviour of the student population, the electrical load is identified and two possible solutions are evaluated to manage the peak load: an orientation of the panels increasing the power at defined time and the use of a storage system. The main strength and weakness points of two systems are investigated by taking into account the Levelized Cost of Energy (LCOE), which reaches 75.3 €/MWh for the orientation of panel and 103 €/MWh for stor…

Power tracking with maximum efficiency for wireless charging of E-bikes

2014

Wireless charging techniques, based on Inductive Power Transfer (IPT), are attractive for Electric Vehicles (EV), due to benefits such as convenience and safety. An accurate valuation of the maximum achievable efficiency in an IPT system is extremely unlikely due to the high sensitivity to parasitic elements variations. Therefore, an “on site” procedure of power efficiency characterization is useful to get a precise description of the efficiency curve and obtain the actual maximum efficiency. In this paper, a power tracking algorithm aiming at efficiency maximization is proposed for a Wireless Charging system. The algorithm aims at finding the maximum power transfer efficiency with respect …

DC link voltage swinging and load current unbalance in fault tolerant VSI. overview and compensation strategies

2015

The topic of this paper is the discussion on the performance of a three-phase fault tolerant inverter with particular attention to the underrated aspect of current unbalances occurring due to the DC link voltage fluctuates after the inverter reconfiguration. Capacitor voltage unbalance affects not only the average output voltage of the inverter, but also its performance. In fact, the inverter performance depends on the fluctuating DC-link voltage components rather than on the average DC-link voltage. After a brief analysis of the voltage fluctuation phenomena resulting from fault tolerant configuration and their effect on load current unbalance, the Authors consider different compensating p…

Physiological compatibility of wireless chargers for electric bicycles

2015

The Inductive Power Transfer represents a viable solution of wireless battery charging for all users of electric mobility. This method brings some benefits to the electric vehicles, being a convenient technique, compared to the conventional wire-based battery charging. Among the electric vehicles, the electric bicycles particularly fit with this innovative method of battery charging. Nevertheless, the physiological effects of the produced magnetic fields need to be taken into account. In this paper, the design of an Inductive Power Transfer system for E-bike wireless battery charging is presented and the measurements concerning the surrounding magnetic field are provided in order to validat…

Contract for the support of household appliances control and monitoring application interworking specification

2007

An Experimental Comparison between an Ironless and a Traditional Permanent Magnet Linear Generator for Wave Energy Conversion

2022

Permanent Magnet Linear Generators (PMLGs) are currently being studied for sea wave energy harvesting. Typically, a PMLG consists of an iron-made armature and a moving translator. The permanent magnets adoption produces parasitic effects, such as cogging force, and the machine weight increment. A solution could be the adoption of an ironless configuration, accepting a power density reduction. This paper investigates the use of ironless PMLGs in sea wave energy conversion systems by an experimental comparative analysis between an iron PMLG prototype and an ironless PMLG prototype, which share the same geometry. The main electrical and mechanical parameters (resistance, mass, and magnetic fie…

Numerical Analysis of Medium Scale PV Plants and Their Power-Flow Control System With a Simple Three Phase Inverter

2012

This paper presents a mathematical analysis of a medium scale Photovoltaic (PV) power generation system connected to the distribution network and of its control system, in which the conversion stage is unique thanks to the absence of a boost chopper. Boost choppers are usually used as actuator for maximum power point tracking (MPPT). The conducted analysis leads to the conclusion that the used inverter presents two degrees of freedom that can be easily exploited in a control system in which the inverter simultaneously realizes the interconnection to the grid and at the same time realizes the MPPT control. The structure of the control system is then presented, discussed and then validated by…

Master-Slave Control of Battery/Supercapacitor Based Hybrid Energy Storage System for E-Vehicle Application

2022

In this paper, management and control problem of hybrid energy storage system (HESS) has been solved by master-slave control strategy. Heuristic fuzzy rules based algorithm is developed for optimal power sharing between different power sources. The master control is followed by a slave level controller, designed by using terminal synergetic control method for tracking. Moreover, the stability analysis of closed-loop system has been carried out by using lyapunov theory. Finally, the proposed method has been tested in MATLAB/Simulink environment under Worldwide Harmonised Light Vehicle Test Procedure (WLTP).

Comparison between Different Dynamic Reconfigurations of Electrical Connections for partially shaded PV Modules

2018

This paper presents an economical investigation on the benefits related to the employment of reconfiguration systems for photovoltaic plants. More in detail, different structures of reconfigurators are proposed and, in order to evaluate the economical convenience on their installation, the Net Present Value is used as a validation element. Significant results are carried out from the proposed analysis.

CO<inf>2</inf> reduction exploiting RES for EV charging

2016

The world is facing an urgent need to reduce emissions, limiting pollution for a better quality of life. This objective has to be reached by all cities and governments worldwide. This paper focuses on the field of transportation, which is greatly responsible for air pollution, mainly in cities and urban areas such as towns, airports and seaports. The diffusion of electric vehicles (EVs) enables a significant reduction of air pollutants emitted by combustion engines; however, their recharge can affect the total pollution by their increasing energy demand. A solution is the use of Renewable Energy Sources (RES) to charge EVs. This paper analyzes the feasibility of integrating EVs and RES, foc…

A Low-cost, Real-time Monitoring System for PV Plants based on ATmega 328P-PU Microcontroller

2015

This paper presents a real-time monitoring system for PV power plants based on a microcontroller Atmega328P-PU. The proposed system, whose performances can be relatively close to those achieved with commercial monitoring systems, is simple, low-cost and open source technology-based. In addition, a user interface, capable to communicate through a wireless network by using a standard communication protocol IEEE 802.15.1, is here presented. From the experimental tests described and discussed in this paper it is demonstrated that the proposed monitoring system provides, with adequate accuracy, all the information about the operating status of the PV plant, even during fault conditions.

Performance comparison of tubular linear induction motors with different primary winding connections

2014

This paper presents an experimental characterization and comparison of the performances achieved by a tubular linear induction motor (TLIM) prototype with different typologies of primary winding connections. In particular, three configurations are described: full-pitch star, 5/6 shortened pitch star and 5/6 shortened pitch double star. For this purpose, an experimental test bench at the SDESLAB laboratory (University of Palermo) has been set-up and the results obtained from the tests have allowed to identify which type of winding configuration can be chosen in dependence of the type of application intended for the motor. In addition, this experimental study is suitable for TLIM winding desi…

Different scenarios of electric mobility: Current situation and possible future developments of fuel cell vehicles in Italy

2020

The diffusion of electric vehicles in Italy has started but some complications weight its spread. At present, hybrid technology is the most followed by users, due particularly to socioeconomic factors such as cost of investment and range anxiety. After a deep discussion of the Italian scenario, the aim of the paper is to recognize whether fuel cell technology may be an enabling solution to overcome pollution problems and respect for the environment. The opportunity to use fuel cells to store electric energy is quite fascinating&mdash

Design and simulation of a fast DC recharging station for EV

2017

In this paper a detailed description of the design and simulation of a DC ultra-fast recharging station for Electric Vehicles is carried out. The system consist of a single AC/DC grid connected inverter, a DC-Bus and two DC/DC converter to recharge the batteries of the EVs. The system also has the vehicleto- grid (V2G) capability. The design of the components of the system and the control schemes are explained and a simulation of the system, performed in Matlab/Simulink environment is presented.

Hybrid Energy Storage Systems: A Brief Overview

2022

In this paper, a brief overview on the Hybrid Energy Storage Systems (HESSs) is provided. In literature, different architectures are chosen to realize the HESSs, and they are based on the principal aim of the HESSs employment. In this paper, the most used HESS topologies are presented, with particular attention to the active, passive and semiactive topologies, highlighting their characteristics. To have a complete schematic idea of the HESSs application, a focus on the principal sizing methodologies is provided, distinguishing the conventional approaches and the advanced ones, exploiting their main applications. Together with a proper sizing, a correct power-sharing strategy is one of the H…

A novel correction method for a low cost sensorless control system of IPMSM electrical drives

2008

In this paper a novel correction method for sensorless Field Oriented Control System of Brushless internal Permanent Magnet Electrical Drives is introduced discussed and experimentally validated. The novelty of this control system is the estimation of rotor speed and angular position is based on the back electromotive force space vector determination, without the aid of voltage probes. Actual voltage signals needed for estimation are replaced with the reference ones given by the current controller. This choice obviously introduces an error that have been vanished by means of a new compensating function or with the aid of data coming from experimental tests. Experimental verifications of the…

Efficiency Enhancement of Permanent-Magnet Synchronous Motor Drives by Online Loss Minimization Approaches

2005

In this paper, a new loss minimization control algorithm for inverter-fed permanent-magnet synchronous motors (PMSMs), which allows for the reduction of the power losses of the electric drive without penalty on its dynamic performance, is analyzed, experimentally realized, and validated. In particular, after a brief recounting of two loss minimization control strategies, namely, the "search control" and the "loss-model control," both a new modified dynamic model of the PMSM (which takes into account the iron losses) and an innovative "loss-model" control strategy are presented. Experimental tests on a specific PMSM drive employing the proposed loss minimization algorithm have been performed…

Italian incentive strategy and regulations on small wind power turbines: A critical overview

2016

Small wind power industry in Italy had its kick-start in 2009, after the Government implemented two measures introducing both the simplified regime and incentive rates for small wind power plants. In the last six years, a lot of plants and small wind turbines have been installed in Italy, especially in the South. Aim of this paper is to examine how local standards, incentive policy and regulations have affected the spread of small wind turbines in Italy. After examining national and regional legislation, an analysis of the data on the penetration of wind systems in Italy has been carried out, with particular attention to six Southern regions (Basilicata, Calabria, Campania, Apulia, Sardinia…

The use of sea waves for generation of electrical energy: a linear tubular asynchronous electrical generator

2007

A linear tubular asynchronous generator to be used as generator driven by seawave is presented. The design criteria of a TLIM with hollowed iron induced part as well as the technological processes to be adopted and the materials utilized in the various parts are described. The methodologies for mechanical assembling and electric wiring are considered too. Finally, the prototype with bimetallic induced part that has been designed and built is presented and some experimental results on electrical and mechanical variables are shown.

New solutions for prefabricated secondary substations in the view of sustainability

2016

The secondary substations will assume an important role as “smart nodes” of the smart grid. So in few years there will be a widespread dissemination on the territory of this apparatus. Consequently, great care have to be taken not only on safety issues, but also on the constructive methodology, in order to determine low environmental impact and decommissioning cost. This paper focuses on innovative solutions for the realization of prefabricated secondary substations, in the direction of sustainability. Innovative layout and enclosure topologies have been here taken into account. In particular, by considering that the substation concrete box is, at the same time, uneconomical and with strong…

Experimental Investigation on Magnetic Field Effects of IPT for Electric Bikes

2018

The wireless power transmission (WPT) is increasingly representing a promising technology and an innovative solution, especially for the electric vehicles (EVs) battery charging. The inductive power transfer (IPT) is the standard technology of wireless charging: the energy transfer occurs between two magnetically coupled coils. The IPT-based battery charging is especially convenient for E-bikes and the physiological effects related to the generated magnetic fields should be estimated. In this context, this work presents a 200Â W prototype of wireless battery charger for E-bikes. In addition, the measurements regarding the surrounding magnetic field are given in detail in order to evaluate t…

Current fault signatures of Voltage Source Inverters in different reference frames

2016

This paper considers different current patterns used to identify the correct fault signatures in Voltage Source Inverters (VSI). At the beginning, the Authors consider the currents patterns from which a simple or a double fault can be encompassed both in the case of controllable device only or with its free wheeling companion diode. After the discussion of diagnosis algorithm suitable for electrical drives and principally based on a persistent near zero current condition current in the natural phase reference frame, the stationary reference frame is then considered as a tool to identify both the faulted phase as the device or various combination of faulted devices. On the contrary, the Auth…

Highly Compact Partial Power Converter for a Highly Efficient PV-BESS Stacked Generation System

2022

The inherently intermittent nature of photovoltaic (PV) energy has brought increasing interest towards the integration between PV sources and Battery Energy Storage Systems (BESS). In this paper, a Series Partial Power Processing (PPP) converter based on Capacitive Power Transfer (CPT) is proposed to integrate PV and BESS in a grid-connected inverter system. The proposed converter has been simulated according to a PV string capable to provide 1430 W under full irradiance conditions, a BESS nominal voltage equal to 215 V and a solar inverter assumed to operate with a minimum voltage of 150 V and a maximum current of 10 A. Simulation tests carried out at different conditions of solar radiatio…

Performance evaluation of a multisource renewable power converter prototype

2014

Novel Energy Modelling and Forecasting Tools for Smart Energy Networks

2015

A novel Energy Modelling and Forecasting Tool (EMFT) has been adopted for use in the VIM SEN (Virtual Microgrids for Smart Energy Networks) project and this paper gives an insight of the techniques used to provide vital support to the energy market, in particular to energy aggregators. A brief description of one of the test sites where data has been collected for validation of the EMFT will be outlined and some examples shown. The information and predictions will then be used by a decision support system to dynamically adjust energy delivery and consumption, by giving advice to users and operators on actions they can take to obtain a better match between energy supply and demand that increa…

Electric Vehicles and Psychology, Part 2

2021

This paper presents the main psychological attitudes influencing the transition from conventional ICEV to BEV, and it is the continuance of Electric vehicles and psychology, part 1, [1]. This part faces the range anxiety problem, the risk of explosion of batteries, the autonomous silver vehicles and the experience of driving electric vehicles. If the reader is looking for simple answers, the author does not recommend the subsequent reading, since few paradoxes will be solved.

Design, implementation and experimental results of a wireless charger for E-bikes

2019

Based on the Inductive Power Transfer (IPT), the wireless energy transmission is increasingly representing an attractive solution for vehicle battery charging. Due to its high smartness, the wireless solution may be considered an interesting battery charging method for electric bicycles, as they represent light-weight and flexible means of transportation. According to the Vehicle-To-Grid (V2G) concept, the wireless power flow can occur in both the alternative directions: from the grid to the battery or in the opposite way. A Bi-Directional Inductive Power Transfer (BDIPT) system is therefore particularly convenient in the scenario of a multi-parking area. For the E-bike application, a bicyc…

Wind Electrical energy generating systems EMC. A dedicated experimental simulator for tests

2008

In wind electrical energy generating systems, due to fast voltage and current fluctuations, the power converter represents a source of electromagnetic disturbances. EMI problems of stand alone wind generators are here analysed in order to take into account many different power quality problems which result in voltage fluctuations and harmonics in the net. This paper, moreover, presents a wind turbine experimental simulator (WTES) that moves a wind electrical energy generating system (WEEGS) to carry out EMI measurements and the relative experimental results. The WEEGS here taken into account comprises a wound rotor induction generator (WRIG) in which the frequency transformation from the ro…

Evaluation of performance and efficiency and type approval of an electrically assisted bicycle drive

2013

The diffusion of electrically assisted bicycles gives rise to the need of the evaluation of the performance and efficiency of the electric drive that supply it. In this paper, is presented a test bench for the estimation of the electric drive output torque under several speed and load conditions. Moreover, the test bench detects the electrical and mechanical parameters that allow to evaluate the electrical drive efficiencies. The test bench has been designed in agreement with the Directive 2002/24/EC of the European Parliament since it detects the maximum continuous rated power (that must be lower than 0.25 kW) and evaluates if the output is progressively reduced and finally cut off as the …

MATLAB-based simulator of a 5 kW fuel cell for power electronics design

2013

Abstract In the last few years, renewable energies have been encouraged by worldwide governments to meet energy saving policies. Among renewable energy sources, fuel cells have attracted much interest for a wide variety of research areas. Since combined heat-power generation is allowed, household appliances are still the most promising applications. Fuel cell-based residential-scaled power supply systems take advantage by simultaneous generation of power and heat, reducing the overall fossil fuel consumption and utilities cost. Modelling is one of the most important topic concerning fuel cell use. In this paper, a measurement-based steady-state and dynamic fuel cell model is presented. The …

Proof of Concept of an Irradiance Estimation System for Reconfigurable Photovoltaic Arrays

2015

In order to reduce the mismatch effect caused by non-uniform shadows in PV arrays, reconfigurable interconnections approaches have been recently proposed in the literature. These systems usually require the knowledge of the solar radiation affecting every solar module. The aim of this work is to evaluate the effectiveness of three irradiance estimation approaches in order to define which can be well suited for reconfigurable PV arrays. It is presented a real-time solar irradiance estimation device (IrradEst), implementing the three different estimation methods. The proposed system is based on mathematical models of PV modules enabling to estimate irradiation values by sensing a combination …

Environmental benefits through new distributed on site control actions inside European apartments

2008

Energy management control actions inside apartments and detached houses have to be carried out in order to reduce CO2 emissions. In this work, new control actions turned to the reduction of both electrical energy losses and electrical energy consumptions inside typical European (Italian, French, German and United Kingdom) apartments are proposed. These actions are of the ldquoLoad Shiftingrdquo type, that makes the apartment daily load profile as flat as possible, and of the ldquoDistributed on Site (DoS)rdquo type consisting in heating the water needed by dishwashers and washing machines inside instantaneous gas water heaters (IGWHs) instead of inside the household appliances themselves. T…

Comparison between 3-ph and 6-ph PMSM drives for the electric propulsion of unmanned aerial vehicles

2021

The full electric aircraft concept requires accurate design and suitable choice and integration of all the used components. Obviously, the electric propulsion drive is one of the most important on-board equipment. Both power converters and electric motors must have low weight, suitable overload capacity and high reliability. In this paper, two possible solutions of electric propulsion motor for unmanned aerial vehicle are investigated. Sizes, weight and some features of a three-phase PMSM motor are compared to those of a six-phase motor obtained by an appropriate rewinding of the armature, with fixed stator and rotor magnetic circuits. The losses obtained from the numerical analyzes are com…

Closed-loop bandwidth impact on MVSA for rotor broken bar diagnosis in IRFOC double squirrel cage induction motor drives

2013

This paper investigates the detectability of rotor broken bars in indirect rotor flux oriented control (IRFOC) for variable speed double cage induction motor drives, using vibration signature analysis techniques. The Impact of the closed loop control system cannot be neglected when the detection of rotor asymmetries in the machine is based on the signature analysis of electrical or mechanical variables. Therefore, the investigation of rotor fault components for different bandwidths of closed-loop regulators is necessary to evaluate its relevance in the above listed variables. This paper investigates the impact of the control system on relevance of the fault components computed from axial an…

Enhanced Modelling for Extended Performance Analysis of Interior Permanent Magnet Synchronous Machine Drive fed with Cascaded H-Bridges Multilevel In…

2021

This paper presents a comparative simulation analysis of an Interior Permanent Magnet Synchronous Machine (IPMSM) performance once fed by a traditional three-phase two-level inverter and then using a three-phase five-level Cascaded H-Bridges Multilevel Inverter (CHBMI). For this purpose, an enhanced mathematical model of the IPMSM, that take into account simultaneously saturation, cross-coupling, spatial harmonics and iron loss effects, has been employed. Furthermore, two different PWM modulation strategies have been considered. The study was conducted for several working conditions, evaluating the impact of CHBMI adoption on the IPMSM performance in terms of improved efficiency and torque …

Fuel cells for household appliances: Experimental test of power management algorithms

2013

In this paper, fuel cell - based hybrid power supplies for household appliances are addressed. The profile of residential power consumption is evaluated during working, non-working days in both summer and winter periods. The worst-case load power demand is therefore highlighted. A 5kW Nuvera PowerFlow proton exchange membrane fuel cell for household appliances is tested. On the basis of the characterization of the fuel cell stack under test, stand-alone and fuel cell - battery active hybrid power supply architectures are both considered. Experimental validation of three power management algorithms is proposed in terms of hydrogen consumption, cost and energy saving. Power management algorit…

Experimental Prototyping of a Microgrid with Mechanical Point of Common Coupling

2020

The smartgrid is a key technology for the sustainable and smart utilization of the renewable energies. In this paper, a prototyping of a microgrid, assembled at the Sustainable Development and Energy Saving Laboratory (SDESLAB) of the University of Palermo, is presented and discussed. In detail, the microgrid presents only one mechanical point of common coupling (PCC) with the main grid and it is electrically separated from the main grid. In this way, the voltage variations of the main grid do not affect the microgrid electric quantities behavior. In order to validate the effectiveness of the voltage and frequency control, several experimental tests and analysis have been carried out. In de…

A simple and accurate model of photovoltaic modules for power system design

2014

The use of slightly asymmetrical windings for rotating electrical machines

2018

Historically, asymmetrical windings in electrical machines have been rarely used and only for specified needs, because the adoption of symmetrical configurations has always been considered the only solution during the design stage of electrical machines. The aim of this work is to demonstrate with several examples that the use of slightly asymmetrical windings can be a reasonable choice and, in certain cases, a favorable option during the machine design stage, allowing the possibility of selecting a wider range of slot/pole number combinations, without affecting the performances of the machines. More in detail, an interior permanent magnet synchronous machine equipped with a symmetrical 3-p…

Performance Comparison of modified modulation Techniques for Quasi-Z-Source Converters

2020

The single-stage converters represent an innovation in the field of power electronics thanks their features. Aim of this work consists in the improvement of the performances of quasi-Z-Source converters by adopting a modified modulation technique, which is based on the Maximum Constant Boost Control (MCBC) and Switching Frequency Optimal (SFO). The results in terms of voltage stress and harmonic content are compared with those obtained with conventional techniques, demonstrating the effectiveness of the proposed modulation scheme.

Achieving maximum power transfer in a multi-source renewable system

2014

In this paper, a multi-source DC-DC power system is proposed for renewable applications. A multi-input, single inductor power converter controlled by two interacting control loops is designed. The steady-state and small-signal analysis of the designed system is carried out. A battery-photovoltaic system is designed as an application example. Both the output voltage and maximum power point of solar panels are properly controlled to achieve high performances of the whole system. Experimental results on a 48 V laboratory prototype are presented to discuss system performances.

A new high accuracy software based resolver-to-digital converter

2004

Tracking resolver-to-digital conversion (R/D converter or simply RDC) has emerged as one of the most robust method for obtaining high resolution position and angular speed information from resolvers. In this paper a low cost software based RDC is presented. The main features are: high accuracy, simple set up, high reliability and stability and good performances. Some experimental results, showing the capabilities of the proposed system, are presented and discussed. An output signal comparison between the proposed RDC and a commercial encoder is also presented.

Electrical distribution substation remote diagnosis and control system

2014

This paper presents the conception, design, set up and realization of a prototype system for telemanagement of a MV/LV substation. The prototype has been developed according to the current standards. This system allows to monitor the status of the MV/LV substation box, of the medium voltage equipment, of the transformer and of the low voltage equipment. In particular, the system acts when some specified events occur. The prototype has been realized by using a DAQ; the software that implement the telemanagement system has been developed in LabVIEW environment. The system allows a remote monitoring of the quantities of interest that is carried out using the TeamViewer software able to establi…

A semi-empirical multipurpose steady-state model of a fuel cell for household appliances

2013

In this paper, a multipurpose model of a proton exchange membrane fuel cell for household appliances is proposed. According to a conventional mathematical approach, the proposed model is derived from the physical and electro-chemical equations that rule the fuel cell behaviour. Differently from existing models, a parametric analysis is carried out and a few tunable parameters are accurately selected and identified. Furthermore, this paper proposes an innovative technique of unique model architecture which enables the designer to solve by himself the trade-off between complexity and accuracy on the basis of the specific applications. Three different choices could be performed by the designer…

A modular approach in teaching thyristor rectifiers with equation-oriented softwares

2014

This article is devoted to some issues of teaching power electronics in university courses. In the modern education system the students are expected to be no longer subject of passive learning, but that, within a certain extent, they collaborate in their training interactively with the teacher to develop the applications and the topics of the studied framework. For this purpose, this article presents a modular approach for teaching module regarding three-phase thyristor rectifiers. A simulator based on the MATLAB equation solver has been developed by considering the detailed physical operation of such converters. In particular, the realized simulator takes various aspects into account, incl…

Pd-Co-Based Electrodes for Hydrogen Production by Water Splitting in Acidic Media

2023

To realize the benefits of a hydrogen economy, hydrogen must be produced cleanly, efficiently and affordably from renewable resources and, preferentially, close to the end-users. The goal is a sustainable cycle of hydrogen production and use: in the first stage of the cycle, hydrogen is produced from renewable resources and then used to feed a fuel cell. This cycle produces no pollution and no greenhouse gases. In this context, the development of electrolyzers producing high-purity hydrogen with a high efficiency and low cost is of great importance. Electrode materials play a fundamental role in influencing electrolyzer performances; consequently, in recent years considerable efforts have b…

Economic benefits of the use of a PV plants reconfiguration systems

2015

This paper shows the economic convenience of the application of a reconfiguration system for photovoltaic plants, considering the incentives system in different Countries. The reconfiguration is an alternative to the Distributed Maximum Power Point Tracking, DMPPT, technique used to overcome the mismatch problem in Photovoltaic, PV, plants. The reconfiguration techniques employ a microprocessor-based system that modifies the layout of the PV plant by physically changing the connections among modules. After having presented the working principle of the PV reconfiguration system allowing the improvement of the efficiency of the same plant and the relevant installation, the main strength and w…

Selective Harmonic Elimination in a 5-Level Single Phase Converter with FPGA Based Controller

2018

Multilevel converters are becoming popular in high-power applications such as motor drives, renewable energy systems and distribution systems. Among all modulation techniques, selective harmonic elimination methods offer high quality voltage waveforms with operations at low switching frequency, hence, they are especially suitable for high-power applications. In this paper, a new analytical expression for the SHE problem formulated for a five-level converter is introduced, which is able to calculate the exact value of the switching angles. After a mathematical description of the proposed approach, this manuscript reports simulation and experimental results and analysis showing achievable res…

Reduction of the uncertainty in the measurements of magnetic fields

2014

The paper deals with magnetic field measurement, carried out by using a broadband and isotropic instrument. These measurements are characterized by a very high uncertainty values if compared with the ones usually related to other electrical measurements. For these reasons, if the measurements are performed to assess the exposure of human beings, these large uncertainty values imply a high risk of wrong decision when there is the need to establish if a site complies or does not comply with a specified emission limits. A reduction of the uncertainty values implies a reduction of the risk. With this aim, we propose an approach which, in particular but very typical cases, allows an effective re…

Experimental Characterization of a Double Receiver Dynamic Wireless Charging System

2020

The aim of this work is the characterization of a dynamic wireless charging system low power prototype and the validation of a simplified mathematical model of the employed double D coils. The difference between a single receiver and a dual receiver system is also shown, highlighting how the last one can significantly reduce the costs of the charging infrastructure.

A photovoltaic charging system of an electrically assisted tricycle for touristic purposes

2013

In this paper the design, realization and testing of a photovoltaic charging system suitable for the management of an electrically power assisted tricycle are described. This vehicle uses a photovoltaic module as a source of electric energy for the battery recharging. In this work, an overview on the needs of sustainable mobility and on the commercial electrically power assisted velocipedes is presented. The electrical rickshaw prototype, developed in the SDELab laboratory of the University of Palermo, is presented in detail, underlining the design, implementation and developing phases of the photovoltaic charging system assembled on the velocipede. Moreover, tests oriented on the setting u…

Design of a solar-battery-thermoelectric power converter prototype

2015

In this paper a multisource renewable energy system for high-current applications is proposed. The power architecture is based on a multi-input power converter including control and reconfiguration subsystems. Independently of the type of connected renewable sources, a proper control of the output DC voltage bus is provided as well as a proper control on the operating point of each renewable source to achieve the maximum power transfer. A 48V thermoelectric-photovoltaic-battery system in a three input configuration is designed. Three interacting feedback networks are implemented: the outer loop which controls the output voltage and as many inner loops as connected renewable sources to achie…

A Novel Neural Approach to the Determination of the Distribution Function in Magnetic Preisach Systems

2004

This paper presents a novel method to identify both the functional dependence of the Preisach function as well as its numerical parameters on the basis of some known magnetic behavior. In this paper, the identification of the Preisach function of a material is performed by using a neural network trained by a collection of hysteresis curves, whose Preisach functions are known. When a new hysteresis curve is given as input to this neural network, it is able to give as output both the functional dependence of the Preisach function as well as its numerical parameters.

Overview and performance comparison of grid synchronization algorithms

2014

Distributed power generation units are experiencing an impressive growth. Consequently, the amount of energy injected by non-linear loads as power converters is expected to increase. Stability and quality of the overall grid are heavily affected by performances of grid-side converters. In this paper, an overview of grid-synchronization technique is proposed. The grid-side inverter is implemented in MATLAB/Simulink® environment including current control and grid-synchronization section. Both Synchronous Reference Frame (SRF) and Decoupled Double Synchronous Reference Frame (DDSRF) PLL algorithms are implemented. A performance comparison is carried out under ideal and unbalanced utility condi…

Energy management of multi-carrier smart buildings for integrating local renewable energy systems

2016

The proposed paper aims at defining a Building Management System (BMS) able to control energy flows inside a smart building integrated with various energy networks and Renewable Energy Resources (RES). The smart building envisaged in this work interacts with different energy carriers and is equipped with cogeneration and RES systems, as well as storage devices, which enable a certain degree of flexibility in the energy usage. The smart building is modelled as a multi-carrier hub, by defining the graphical and mathematical model of the building system. Moreover, the control criteria of the BMS are explained and the implementation of the BMS itself is depicted, along with some early results. …

WITHDRAWN: Perspective on hydrogen energy carrier and its automotive applications

2013

A review of multiple faults diagnosis methods in Voltage Source Inverters

2015

This paper examines, as in short review, the methods of diagnosis of simple and multiple faults on Voltage Source Inverter (VSI). The methods examined here are essentially based on the inspection of the load currents. Some of these diagnosis methods are characterized by low computational effort, other for a better reliability avoiding faultless positive tests. Some solutions are characterized by a share of these benefits while others prefer an enforcement of trustworthiness, in spite of the lower calculation amount. The analysis of the technical literature, certainly, offers a glimpse about the creation of new algorithms and significant advances for the future.

Experimental Investigation on the Performances of a Multilevel Inverter Using a Field Programmable Gate Array-Based Control System

2019

The Field Programmable Gate Array (FPGA) represents a valid solution for the design of control systems for inverters adopted in many industry applications, because of both its high flexibility of use and its high-performance with respect to other types of digital controllers. In this context, this paper presents an experimental investigation on the harmonic content of the voltages produced by a three-phase, five level cascaded H-Bridge Multilevel inverter with an FPGA-based control board, aiming also to evaluate the performance of the FPGA through the implementation of the main common modulation techniques and the comparison between simulation and experimental results. The control algorithm…

Local DoS applications with micro wind generation systems

2015

In this paper a wind electrical power generation system for Distributed on Site (DoS) applications is proposed. This system was developed and conceived in order to guarantee simple installation, use and service, obtaining a product that can be easily industrialized and put into the market with limited costs. The field of application of such an electrical generation system is addressed towards domestic or at the most toward condominium applications concerning moreover the opportunity of working in addition to combined photovoltaic and solar-thermal systems to enhance the renewable energy generation at house level (DoS). The proposed system has its hot spot in the blades shape, in the wind fl…

Remote diagnosis and control of wheelchair electrical drive systems

2005

A new Diagnostic and Protective System (DPS) suitable for wheelchair electrical drive applications has been prepared. Such a system is able to perform both monitoring and long-distance transmission of key signals that are used as pre-fault and fault indicators. The system, moreover, may detect several anomalous working conditions by means of reliable diagnosis procedures and carries out actions to protect the electrical drive and to drive the disabled people in safe conditions. In particular the design, the realization and the performance analysis of the new dedicated diagnostic system, which exploits a programmable logic controller (PLC) as DRS hardware, are described and discussed. The ef…

Experimental investigation on different rainfall energy harvesting structures

2018

In this paper proposes an experimental comparison between different rainfall harvesting devices and the study of the corresponding electrical rectifying circuit. More in detail, three harvesting structures are considered: the cantilever, the bridge and the floating circle. For each of the proposed structure, different waveforms have been acquired and discussed. The processed data have been compared in order to suggest the best choice for the rectifying circuit, from the simplest one to the most endorsed in the technical literature.

An IPMSM torque/weight and torque/moment of inertia ratio optimization

2014

In this paper, a torque/weight and torque/moment of inertia ratio optimization procedure for interior permanent magnet syncronous motors (IPMSMs) is presented. More in detail, a performance comparison between several IPMSM rotor structures has been carried out in order to determine the optimum geometry that can maximize the torque/weight and torque/moment of inertia ratios. A commercial motor, with known electrical and mechanical characteristics, has been taken as reference. Its rotor structure has been modified several times, obtaining different rotor geometries and, therefore, many IPMSM models with different electrical and mechanical characteristics. The finite element method (FEM) analy…

Speed control of tubular linear induction motors for industrial automated applications

2016

The Tubular Linear Induction Machine (TLIM) has acquired great relevance over the past years for industrial automated applications. For this purpose, the complete modeling, simulation and determination of the parameters of a TLIM is presented in this paper. In addition, the TLIM speed control for this specific application is here described. In order to verify the performances of the proposed system, a test bench has been setup and good agreement is shown from the comparison between measured and simulated results.

A DSP-Based Resolver-To-Digital Converter for High-Performance Electrical Drive Applications

2016

This paper presents a low cost, simple, and highly accurate resolver-to-digital converter (RDC) for electrical drive applications based on an integrated software approach, thus allowing a significant reduction of hardware components count with significant improvements in terms of reliability, reduction of fault rate, and susceptibility to electromagnetic interference (EMI). Particular attention has been addressed to cost which is 25% off over conventional RDC. Simulations and experimental tests confirm the high quality of the proposed system.

An electrochemical route towards the fabrication of nanostructured semiconductor solar cells

2010

This work presents our preliminary results regarding an electrochemical process which allows the growth of nanostructured materials by means of nanopore templates. Also we analyze possible applications of this process to fabricate nanostructured semiconductors, such as CIGS, suitable for photovoltaic devices, and we consider the implications from the perspective of characterization techniques and device modelling when using such a technology.

Modelling, simulation and characterization of Li-Ion battery cell

2019

The decarbonizing process of the transportation system and the spread of unplanned renewables energy source, such as photovoltaic and wind energies, brought the constant need of ever more efficient energy storage technologies. Among these technologies, batteries, particularly the li-ion chemistry, are widely used in automotive and energy storage applications. For an optimized management of the cell it is advisable to have models that can accurately describe cell behaviour. In this paper a battery model for performance simulation in automotive application is identified. The main shapes of battery cells with their own advantages and disadvantages are shown, and a roundup of the best available…

Manufacturing tolerances effects on PV array energy production

2014

This paper investigates the tolerance effects of commercial photovoltaic modules in terms of electrical energy reduction of photovoltaic plants. Several commercial modules, having the same rated power, present different power tolerance values. A wide tolerance is an indicator of possible defects or differences in the production process and is responsible of remarkable reductions in the electricity production of photovoltaic plants. In this paper, thanks to the development of a suitable simulation tool, several simulations have been carried out, considering different tolerance and shading conditions for the PV array. Simulation results quantify the peak power value of the different plant con…

A Novel Symmetrical Boost Modulation Method for qZS-based CHB Inverters

2020

Quasi-Z-source cascaded H-bridge (qZS-CHB) inverters are arising as an innovation in the field of the electrical conversion for PV applications. This type of converters inherit the advantages of multilevel inverters and single-stage configuration. In this context, this paper proposes a novel symmetrical boost modulation strategy for qZS CHB multilevel inverters to increase the performance in terms of voltage stresses and power quality. The novelty lies in the adoption of a different concept to generate the shoot-through states compared to the traditional methods. Simulation analysis in a grid connected application to evaluate the benefits of this boost method is performed in the MATLAB/PLEC…

A device for PV modules I-V characteristic detection

2013

In this paper an electronic load suitable for the PV module I-V characteristic curve fast detection is presented. This device is designed in agreement with the IEC 82 Techinical Committee Standard since it allows the detection of the characteristic starting from voltage values even lower than 3% of the PV module open circuit voltage. The device main features are short time characteristc detection (2 s), limited ripple of the detected characteristic and low cost. Its validation is carried out by comparing measured data with data from simulations. Simulations are carried out considering two different commercial PV modules and by implementing in Matlab-Simulink environment the four lumped para…

Fast procedure for the calculation of maximum slot filling factors in electrical machines

2017

This paper presents an algorithm for the calculation of maximum slot filling factor in electrical machines. The determination of whole wire cross section that occupy the area of a stator slot is very important in order to estimate the copper losses: The greater is the filling factor the lower are copper losses. The main goal of this paper is to define a simple algorithm for the determination of slot filling factors suitable for all type of slot profiles. The algorithm can be considered as an additional useful tool for the fast design of electrical machine windings.

Power losses comparison between Silicon Carbide and Silicon devices for an isolated DC-DC converter

2021

In recent years, new efficient power devices have been implemented. Silicon Carbide has replaced silicon as regards the production and the utilization of many devices, such as MOSFETs, diodes, IGBTs and many others. SiC devices are characterized by a low reverse recovery charge, high carrier saturation velocity, by which it is possible to work at high frequency, and high breakdown voltage. Thanks to the great thermal conductivity and the wide bandgap, these devices can operate at high temperature and reach high voltages and currents. What is important to stress is the fact that power losses in SiC devices are lower than the silicon ones. These are the reasons why these devices are utilized …

On the design of observers robust to load variations for synchronous converters

2015

Due to the ever growing concern on energy efficiency issues, synchronous rectification gained increasing attention in recent years. In the semiconductor industry fast controllers developed for DC-DC converters are typically based on inductor current measures. In this context system costs and performances strictly depend on the current sensor and its proper design. In this paper we present a sensorless synchronous approach based on a current observer. The same observer formulation is valid for the three standard DC-DC converters, simplifying its design for different configurations. Furthermore the designed observers are proven to be robust against load variations, the most uncertain paramete…

New approach for harmonic mitigation in single-phase five-level CHBMI with fundamental frequency switching

2017

The main objective of this paper is to study and analyse the voltage output waveform of a multilevel inverter, to suggest a new approach for harmonic mitigation improving the converter performance. These last type of converters represent a new technology in the field of DC/AC electrical energy conversion, presenting advantages respect to the traditional converters. In fact, the multilevel power converters present a low harmonic content and a high voltage level. The paper considers a five-level single-phase cascaded H-bridge inverter and fundamental frequency modulation techniques. The voltage waveform analysis has allowed to identify a working area of the converter where there are lowest va…

Robust current observer design for DC-DC converters

2014

In recent years several fast response controllers have been proposed for DC-DC converters. The majority of them rely on a cascade control structure involving the inductor's current in the control function as its faster dynamics, respect to output voltage, allows a significant increase in the regulation performance; the drawback is the need of a proper and expensive current sensor. In this paper a simple and robust formulation for the design of a current observer, based on the output voltage measurement is presented. The formulation is common for the three standard DC-DC converters and the resulting observer is robust to load variation. The observers have been tested in a cascade PI control …

Switching Frequency Effects on the Efficiency and Harmonic Distortion in a Three-Phase Five-Level CHBMI Prototype with Multicarrier PWM Schemes: Expe…

2022

The current climatic scenario requires the use of innovative solutions to increase the production of electricity from renewable energy sources. Multilevel Power Inverters are a promising solution to improve the penetration of renewable energy sources into the electrical grid. Moreover, the performance of MPIs is a function of the modulation strategy employed and of its features (modulation index and switching frequency). This paper presents an extended and experimental analysis of three-phase five-level Cascaded H-Bridges Multilevel Inverter performance in terms of efficiency and harmonic content considering several MC PWM modulation strategies. In detail, the CHBMI performance is analyzed …

Finite-Difference Time-Domain Simulation of Tower and Grounding Subjected to Lightning

2015

In this paper the behavior of a tower and its grounding system, subjected to a lightning, is faced. Finite difference time domain (FDTD) method has been chosen in order to study the non-linear time domain behavior of the system. The electromagnetic problem has been described by using two type of first order time derivative equations: Maxwell's equations and Telegraph equations. Aim of this work is to evaluate the possibility of a flashover between tower and power line, by considering different cases of study.

Survey on power increase of power by employment of PV reconfigurator

2015

This paper shows the performance of a PV system under shadow projection on PV panels. The reconfiguration techniques, employing a microprocessor-based system, modifies the layout of the PV plant by physically changing the connections among modules, in order to recover the loss of power due to the shadows. Different cases have been considered to evaluate the increase of power.

Field Oriented Control of IPMSM Fed by Multilevel Cascaded H-Bridges Inverter with NI-SOM sbRIO-9651 FPGA controller

2022

Electrical drives fed by Multilevel Inverters (MIs) are of considerable interest for traction and e-mobility applications. In detail, Cascaded H-Bridge Multilevel Inverter (CHBMI) is a promising solution for electrical drive optimization purposes in terms of efficiency, safety, integration and flexible use of energy sources. The aim of this paper is the experimental implementation of the field-oriented control strategy of Interior Permanent Magnet Synchronous Machine (IPMSM) fed by CHBMI by use of NI-SOM sbrRIO-9651 FPGA controller. This FPGA controller can be programmable in the LabVIEW programming environment with the consequent benefits of graphical programming. The paper address the acq…

Experimental investigation on a cascode-based three-phase inverter for AC drives

2021

High speed electrical drives and machines represent a promising solution to cope with the increasing electrification in several fields, e.g. industrial electronics and mobility. According to that, power electronics is going more and more towards innovative technologies of semiconductor devices, such as Gallium-Nitride (GaN) and Silicon-Carbide (SiC), providing the opportunity of faster switching transients and therefore of higher switching frequencies. A challenging perspective is represented by gaining higher and higher switching frequencies while keeping high voltage and low power losses. In this scenario, the Cascode (CC) configuration can represent a reliable solution in order to reach …

Evaluation of the power quality from a seawave power farm for different interconnection schemes

2007

In this paper we present an approach to the interconnection of a seawave power farm to the grid The generator type used in the farm is a Permanent Magnet (PM) linear generator driven from the seawaves that generates, therefore, highly distorted emfs. We propose and compare two possible ways to interconnect the farm to the grid. One is based on an approach where for each generator there is a conversion subsystem that permits the direct connection of each generator to the a.c. network, the other one is based on an ac.-d.c. converter that is connected to the generator, the converter is connected to a dc link that can receive the power from every unit and that can supply a dc-ac converter direc…

A Model of DC-DC Converter with Switched-Capacitor Structure for Electric Vehicle Applications

2022

In this paper, a DC-DC converter with an innovative topology for automotive applications is proposed. The goal of the presented power converter is the electrical storage system management of an electric vehicle (EV). The presented converter is specifically compliant with a 400 V battery, which represents the high-voltage primary source of the system. This topology is also able to act as a bidirectional power converter, so that in this case, the output section is an active stage, which is able to provide power as, for example, in the case of a low-voltage battery or a supercapacitor. The proposed topology can behave either in step-down or in step-up mode, presenting in both cases a high gain…

Performance of the Shape of Partial Discharge Signal Wireless Probes

2013

This paper focuses on the evaluation of the performances of three different antenna sensors suitable of Partial Discharge (PD) measurements. Monopole, triangular and spherical antennas were simulated by means of the surface moment method. The transmitting system is modeled by a power electronic device with a fault current between two metal plate. The shape of the simulated transmitted and received signals have been compared to verify the sensor the provides the best fidelity among the three. The auto-correlation function and the Pearson correlation index are adopted here for the comparison. A discussion on the dynamic characteristic of the different antenna probes and their use in different…

Forecasts on the development of hydrogen refuelling infrastructures in Portugal

2021

In Portugal, the transition to new forms of mobility has begun in recent years, but there are still obstacles to overcome. Currently, hybrid vehicles (PHEVs) are the most widespread and accepted by the community and that is probably due to range anxiety, having in fact the possibility of double charging (both through the thermal engine and the electric battery). Furthermore, it must be considered that in addition to electric vehicles, another valid alternative to mobility in the near future is the hydrogen vehicles one. These appear to be even more sustainable from the point of view of air emissions, but on the other hand the costs for the production of hydrogen are still too high. Then, th…

A hybrid storage system for wireless sensor nodes powered with energy harvesting

2019

With the recent development of Internet of Things (IoT) and Wireless Sensor Networks (WSN), research and industry have been increasingly focusing on the opportumty of collecting the energy arising from the environment. The Energy Harvesting provides the possibility to supply devices which are placed out of reach or in hazardous spots, e.g. the Wireless Sensor Nodes. Among the different parts belonging to an Energy Harvesting system, the power management network represents a challenging topic. In this paper a Hybrid Energy Storage System (HESS) usable for a WSN powered with Energy Harvesting, based on a battery-capacitor integration, is presented. The experimental results concerning the asse…

Forecasting the diffusion of hydrogen EV refuelling infrastructures in Italy

2019

In Italy the electric vehicle revolution is arrived but it still has difficulties to take off. At the moment hybrid technology would seem the most quoted, due especially to range anxiety. The aim of this work is to understand if the fuel cell technology can find place in Italy. The possibility to use fuel cell to storage electric energy is quite interesting: the charging times will be reduced, and heavy passenger transportation should be easily faced. Basing on the existing history and analysis of the information accessible, this paper addresses the existing e-mobility scenario in Italy and predicts the cities in which a hydrogen refuelling infrastructure should be more remunerative, in ord…

Experimental investigation on high efficiency real-time control algorithms for IPMSMs

2014

This paper describes an experimental investigation on the power losses variations occurring in an Interior Permanent Magnet Synchronous Motor (IPMSM) with respect to the direct axis current component. Such investigation can be useful to determine a mathematical model accounting for copper, iron and mechanical friction losses, and for the arrangement of a speed control drive system equipped with a real-time power losses minimization algorithm. In particular, a test bench has been set up in order to carry out all measurements and the final power loss identification. The test bed is composed by a IPMSM drive with a field oriented control (FOC) strategy, a power analyzer, a dynamometric brake a…

Design, implementation and experimental results of an inductive power transfer system for electric bicycle wireless charging

2020

The use of renewable energy and the transformation of transport mode are crucial items for achieving an efficient and clean electrical mobility that allow being competitive on the market. In this context the interface between the power system and the Electric Vehicles (EVs) assumes a strategic role. Specifically, wireless energy transmission, based on Inductive Power Transfer (IPT), is an attractive solution for EVs charging. Moreover, the use of electric bicycles or kick scooters as mode of urban transport is continuously growing because they are lightweight, sustainable, easily parking, flexible and efficient transport devices. Owing to its benefits, the wireless power transfer can be con…

A mathematical model to determine the electrical energy production in photovoltaic fields under mismatch effect

2009

Among the electrical energy production systems from renewable sources, the photovoltaic one represents today one of the most efficient and technically tested choice. In this paper the authors present a mathematical model that allows the maximization of the generated power of photovoltaic (PV) plants under unequally radiation conditions. In particular, thanks to the model of a PV plant, unequally radiated, developed in Matlab-Simulink environment, in this paper the mismatch problem of PV plants is dealt with. The simulations curried out allow to assert that by putting into action re-configuration techniques of series-parallel connections of PV plants, under unequally radiation, can allow to …

Dead-time impact on the harmonic distortion and conversion efficiency in a three-phase five-level Cascaded H-Bridge inverter: mathematical formulatio…

2023

To avoid leg short-circuit in inverters, dead time must be introduced on leg gate signals. Dead time affects the inverter output voltage fundamental harmonic amplitude, voltage harmonic distortion and inverter efficiency by introducing additional voltage drops. In this regard, dead time effects have been widely investigated for traditional two-level three-phase voltage source inverters in the literature but not extensively for multilevel topology structures. This paper provides a detailed analysis of dead time impact on the harmonic distortion and efficiency of Cascaded H-Bridges Multilevel Inverters (CHBMIs). For this purpose, a general mathematical formulation to determine voltage drop du…

Design issues for wind farms grid tied Inverter

2017

In this paper the Authors give indications for the design of a grid tied Voltage Source Inverters (VSI) aimed to optimal use in energy conversion from wind source. In particular, the design of the inverter is more focused on the control system planning, with a particular glance on the grid synchronization problem. After the exposition of general issues concerning renewable energies and associated topics, the case of a grid tied inverter is considered and a methodology of design is sketched starting from the consideration of the DC side and also considering the power device losses, the protection issue against over voltages and over-currents, snubber circuits, heat sinks and, finally the con…

Perspective on hydrogen energy carrier and its automotive applications

2014

The paper outlines the concept of energy carrier with a particular reference to hydrogen, in view of a more disseminated employment in the field of automotive applications. In particular hydrogen production is analyzed considering the actual state of the art and recent technologies applied in production from the primary sources (fossil fuels, renewable energies, and water electrolysis). Then the problem of hydrogen storage is considered both from technical and economical point of views. In particular, differences between physical and chemical storage are here considered with a particular glance to the most innovative technologies including carbon nanostructures. A review on the main problem…

A novel improved matlab-based software for the electric and magnetic analysis and design of rotating electrical machines

2015

The aim of this paper is to present a software for the analysis and design of windings of rotating electrical machines, considering both the electric and the magnetic specifications on the machine. The considered machines are induction motors (IM) and PM synchronous motors (PMSM). The software accounts for the case of buried magnets (IPMSM), but with some limits, because the calculations require a much more detailed analysis regarding the magnetic circuit. However, this initial limitation of the software, that will be removed in a later version, does not constitute a major limitation as confirmed by the examples presented in this paper.

A General Mathematical Formulation for the Determination of Differential Leakage Factors in Electrical Machines with Symmetrical and Asymmetrical Ful…

2018

This paper presents a simple and general mathematical formulation for the determination of the differential leakage factor for both symmetrical and asymmetrical full and dead-coil windings of electrical machines. The method can be applied to all multiphase windings and considers Gorges polygons in conjunction with masses geometry in order to find an easy and affordable way to compute the differential leakage factor, avoiding the adoption of traditional methods that refer to the Ossanna's infinite series, which has to be obviously truncated under the bound of a predetermined accuracy. Moreover, the method described in this paper allows the easy determination of both the minimum and maximum v…

Selective harmonic mitigation with asymmetrical staircase voltage waveform for a three-phase five-level Cascaded H-Bridge Inverter

2020

Selective harmonics elimination or mitigation strategies are used in all applications where it is necessary to rise the efficiency and reliability of the overall system. This paper presents a simple approach to reduce the low order harmonics amplitude of an asymmetrical staircase voltage waveform for a five-level, three-phase Cascaded H-Bridge Inverter without solving non-linear equations. Through this simple approach, polynomial equations to evaluate the control angels in real-time operations have been found. The effectiveness of the harmonic mitigation method has been tested through the simulation analysis in MatLab/PLECS environment.

Experimental Investigation on the Performances of Innovative PV Vertical Structures

2019

The sustainable development of our planet is considerably related to a relevant reduction of CO2 global emissions, with building consumption contributing more than 40%. In this scenario, new technological conceptions, such as building-integrated photovoltaic technology, emerged in order to satisfy the requirements of sustainability imposed by the European Union. Therefore, the aim of this work is to provide a technical and economical comparison of the performances of different vertical-mounted innovative photovoltaic systems, potentially integrated on a building instead of on traditional windows or glass walls. The proposed investigation was carried out by means of experimental tests on thr…

Fault Tolerant Ancillary Function of Power Converters in Distributed Generation Power System within a Microgrid Structure

2013

Distributed generation (DG) is deeply changing the existing distribution networks which become very sophisticated and complex incorporating both active and passive equipment. The simplification of their management can be obtained assuming a structure with small networks, namely, microgrids, reproducing, in a smaller scale, the structure of large networks including production, transmission, and distribution of the electrical energy. Power converters in distributed generation systems carry on some different ancillary functions as, for example, grid synchronization, islanding detection, fault ride through, and so on. In view of an optimal utilization of the generated electrical power, fault to…

A platform-independent software for the design and analysis of windings of rotating electrical machines

2014

In this paper the Authors present a highly modular and platform-independent software, being based on the MATLAB® programming environment, which is proposed as a valuable aid in the design and analysis of the windings of rotating electrical machines. Unlike the major part of the commercial software, the cases of both symmetric and asymmetric (unbalanced) windings with any number of phases are here considered. The software can perform a considerable amount of calculations in order to determine automatically the optimal structure of the winding starting from its specifications. It is also able to draw the winding map and gives the results of calculation for the harmonic winding factors. The re…

A New Software Tool for Design, Optimization, and Complete Analysis of Rotating Electrical Machines Windings

2015

In this paper, a new software tool developed by the authors for ac winding design, optimization, and complete analysis is presented. In particular, this software can be used as a valid aid in design and analysis for a wide variety of motor and generator windings with generic number of phases (including the case of those machines in which some slots are left empty), pole pairs, slot number, and so on. The calculation of winding factors and the evaluation of their harmonic distribution is also accomplished. The software is implemented in the MATLAB programming environment. By means of some examples, covering the most relevant winding types, the capabilities of this software will be shown. In …

Automotive Brushless Motor Powered by Fuel Cell

2014

Speed control of double-sided linear induction motors for automated manufacturing systems

2014

The double-sided linear induction motor (DLIM) is acquiring a significant relevance in the application of automated manufacturing systems. For this purpose, the modeling, simulation and determination of the parameters of a double-sided linear induction motor is presented in this paper. Furthermore, the DLIM constant voltage/frequency speed control system for this application is here described. In order to verify the performance of the proposed system, a suitable test bench for the DLIM motor is set-up. From the good agreement shown by the comparison between measured and simulated results, it can be stated that the DLIM model and the speed control system is successfully validated. © 2014 IEE…

Efficient contactless power transfer system for EVs

2016

Based on the inductive power transfer (IPT), the contactless approach allows safe and comfortable operations of battery charging for Electric Vehicles (EVs). In this paper, a contactless system particularly suitable for E-bike battery charging is proposed. A practical realization of the system has been carried out, aiming at the system evaluation in terms of working and efficiency. Through a phase shift modulation, a power regulation has been implemented. The target power level is 100 W.

Improving High Frequency Transformers behavior for DC-DC Converter Used in Electric Vehicles

2018

The paper presents a design procedure for high frequency transformer windings adopted in the DC-DC converter used in electric vehicles. The output of the design procedure is the integration of a 3D printed plastic case in the transformer windings, with the aim to maximize the output power. The proposal design procedure is entirely based on a finite element analysis approach and on a differential evolution algorithm used for the solution of the optimization problem.

Optimal Energy Management of Smart Grids With Plug-In Hybrid Electric Vehicles

2015

In this paper, smart grids based on Renewable Energy Sources are addressed. An Italian case study which has been developed in the frame of the research project i-NEXT (Innovation for green Energy and eXchange in Transportation) is presented. Storage elements are included. Electric and fuel cell powered vehicles' charging stations are here included as local loads. In this paper, power management algorithms and the control logic are described. The control subsystem aims at an efficient management of the involved renewable energy sources avoiding faults in the power system and ensuring a fully functional supply of local loads. A “Service Center” software collecting data from renewable sources,…

Measuring rain energy with the employment of “Arduino”

2016

This paper presents the performances of rainfall energy harvesting through the use of a piezoelectric transducer and an Arduino-based measuring system. Diverse studies agree on the possibility of generating electricity from rainfall, but to date, a study that can measure the quantity of energy produced during rainfall is still missing. The present study begins with results obtained from laboratory researchers using piezoelectric transducers and oscilloscopes — to measure the energy produced from a single raindrop — and concludes with an ad hoc Arduino-based measuring system, aimed at measuring the actual amount of electrical energy produced by a piezoelectric transducer that is exposed to r…

On the harvest of rainfall energy by means of piezoelectric transducer

2013

In this paper a detailed study on the harvest of the energy contained in rainfall by means of piezoelectric transducers is presented. Diverse studies agree on the level of suitable generated voltage on the electrodes of a piezoelectric transducer subjected to rainfall, but a complete characterization on the supplied power is still missing. This work, in order to limit optimistic forecasts, takes into account the behavior of the transducers subjected to real and also artificial rainfall, condition that has shown promising behavior in laboratory. In order to increase the energy harvesting and also define its limits different loads have been taken into account. Only commercial transducers have…

Graded Carrier Concentration Absorber Profile for High Efficiency CIGS Solar Cells

2015

We demonstrate an innovative CIGS-based solar cells model with a graded doping concentration absorber profile, capable of achieving high efficiency values. In detail, we start with an in-depth discussion concerning the parametrical study of conventional CIGS solar cells structures. We have used the wxAMPS software in order to numerically simulate cell electrical behaviour. By means of simulations, we have studied the variation of relevant physical and chemical parameters-characteristic of such devices-with changing energy gap and doping density of the absorber layer. Our results show that, in uniform CIGS cell, the efficiency, the open circuit voltage, and short circuit current heavily depe…

Differential Leakage Factor in Electrical Machines Equipped with Asymmetrical Multiphase Windings: a General Investigation

2019

This paper presents an investigation in terms of degree of unbalance and leakage factor of electrical machines equipped with multiphase windings. The analysis has been carried out through 4800 combinations between slots/poles/phases/layers, analyzing the variability of the leakage factor for each condition and determining the optimal region for its minimization. The obtained results demonstrate that the leakage factor could be considerably reduced with the adoption of slightly asymmetrical windings, which represent a favorable option during the early design stage of electrical machines.

Analysis, characterization and minimization of IPMSMs cogging torque with different rotor structures

2015

This paper presents the analysis, characterization and comparison of the cogging torque components generated by five different IPMSM rotor structures. More in detail, an IPMSM model (named IPMSM1), which is derived from a commercial geometry, is analyzed by using a Finite Element Method (FEM) approach. Then, four other IPMSM models, which are obtained by modifying the IPMSM1 rotor structure and by maintaining the same stator configuration, are proposed and analyzed. From the obtained simulation results, the cogging torque components for each structure are determined and compared. From this comparison, a significant cogging torque decrease is occurring for the modified geometries, without af…

Modelling, Simulation and Characterization of a Supercapacitor in Automotive Applications

2020

The energy storage is one of the most discussed topics among Electrical Vehicles (EVs) research. Currently, supercapacitors (SCs) are collecting even more attention due to their unique features such as high-power density, high life cycle and lack of maintenance. In this paper, a supercapacitor model suitable for the simulation in automotive applications is identified. The model parameters are estimated and used to simulate the behaviour of a commercial SCs bank in different operating conditions. The model is finally validated considering experimental results.

Innovative Computational Approach to Harmonic Mitigation for Seven-level Cascaded H-Bridge Inverters

2020

Low frequency modulation strategies are a good solution to increase the energy conversion efficiency in high power applications. The paper is devoted to presents an innovative way to low order harmonics mitigation for seven-level Cascaded H-Bridge Inverters. In particular, this approach is based on the mitigation of selected harmonics without solve non-linear equations for an extended range of the fundamental amplitude. In fact, in real-Time operation to evaluate the control angles the polynomial equations have been identified. Through circuit simulation analysis in MatLab/PLECS environment, the effectiveness of the harmonic mitigation method has been tested and compared with theoretical re…

Wireless battery charging for electric bicycles

2017

The contactless solution is increasingly spreading as method of battery charging for Electric Vehicles (EVs). The standard technology of contactless EV battery charging is based on the Inductive Power Transfer (IPT) between two coupled coils, one connected to the electrical grid and the other one connected to the rechargeable battery. The IPT provides benefits in terms of safety and comfort, due to the absence of a plug-in operation. In this paper, an overview on the IPT applied to the battery charging of electric bicycles is provided, with some general considerations on the technical implications. Moreover, a prototype of contactless battery charging for E-bikes is proposed and described.

Simplified hybrid PD model in voids: Pattern validation

2013

The purpose of the present work is to show the validation of a new model to simulate the physical phenomenon of partial discharge (PD) produced in air voids inside insulating epoxy resin. The model has been developed on the basis of a new approach that combines the known circuit model of three capacitors with a model used to describe the behavior of the ionized channel inside of the inclusion during the discharge phenomenon, short-circuiting the capacity that represents the void. The approach is based on time-variable conductance of the void, subjected to multistress conditions: voltage, temperature and pressure. The new approach has been developed from a time variable conductivity model us…

Nanostructured lead acid battery for electric vehicles applications

2017

This paper presents an innovative lead acid battery, based on nanostructured active materials. Both charging time and specific energy are greatly enhanced in comparison with commercial lead acid battery. Starting from the extremely valuable performances of the nanostructured battery, also a circuital model, for application in electric vehicle traction, has been specifically developed. The circuital model has demonstrated that an enhanced nanostructured battery allows an increase of traveled distance by electric vehicles.

Effects of post-filtering in grid-synchronization algorithms under grid faults

2018

Abstract The spread of distributed generation systems has reinforced concerns and requirements on grid-tied power converters. The synchronization with the utility voltage vector is a major concern. In the literature, algorithms based on Phase Locked Loops are extensively presented. In spite of adequate performances under ideal and balanced grid conditions, under grid faults great inaccuracies arise. Shortcomings are overcome by advanced algorithms at the expenses of the complexity and computational cost. In this paper, grid synchronization algorithms are addressed. A solution is proposed by introducing a new post-filter stage in a Decoupled Double Synchronous Reference Frame not affecting, …

Technical and economical comparison between different topologies of PV plant under mismatch effect

2014

This paper presents a technical and economical comparative analysis between two topology of photovoltaic plant. In particular the performances of series-parallel (SP) and total cross tied (TCT), topologies are taken into account, referring to a partially shaded photovoltaic plant. Thanks to a simulation model developed, in the paper the mismatch effects due to three different shading conditions, for SP and TCT topology plant, are quantified. Since the TCT solution, even though increase the energy production, raise the complexity of plants as well as their costs, an evaluation of the individual costs of each component of a SP and TCT plant topology, as PV modules, support structure, inverter…

Novel Computational Method for Harmonic Mitigation for Three-phase Five-level Cascaded H-Bridge Inverter

2018

The efficiency of the system is a very important parameter for high power electrical drives applications,. Moreover, in the system the efficiency of the power converter play a fundamental role and for this reason, the soft switching modulation techniques represent the best choice. This paper presents a novel computational method for harmonic mitigation on the output voltage of a five-level, three-phase Cascaded H-Bridge Inverter without solving non-linear equations. Through this simple approach the Working Areas have been identified in which the harmonics reference have minimum amplitude possible. Moreover, polynomial equations to evaluate the control angels have been found. In this way, th…

Comprehensive Modeling and Experimental Testing of Fault Detection and Management of a Nonredundant Fault-Tolerant VSI

2015

This paper presents an investigation and a comprehensive analysis on fault operations in a conventional three-phase voltage source inverter. After an introductory section dealing with power converter reliability and fault analysis issues in power electronics, a generalized switching function accounting for both healthy and faulty conditions and an easy and feasible method to embed fault diagnosis and reconfiguration within the control algorithm are introduced. The proposed system has simple and compact implementation. Experimental results operating both at open- and closed-loop current control, obtained using a test bench realized using a dSPACE system and the fault-tolerant inverter protot…

Energy Management via Connected Household Appliances

2008

The study reported hereafter provides results based on a campaign of simulations conducted by University of Palermo on the basis of its knowledge in the field Energy Value Chain and in the field of Energy Management (EM) for household appliances. Inputs from CECED Convergence WG has been fundamental to base that study on realistic data and cases. Moreover, the so called EM study, offers also a clear picture about the opportunity to have energy management applications and services in house, being those opportunities strictly related to the cost of in- frastructure needed and to the benefits belonging to different actors in the energy value chain. Energy savings have been considered both in t…

An exact method for the determination of differential leakage factors in electrical machines with non-symmetrical windings

2016

An exact and simple method for the determination of differential leakage factors in polyphase ac electrical machines with non-symmetrical windings is presented in this paper. The method relies on the properties of Gorges polygons that are used to transform an infinite series expressing the differential leakage factor into a finite sum in order to significantly simplify the calculations. Some examples are shown and discussed in order to practically demonstrate the effectiveness of the proposed method.

Overview and experimental analysis of MC SPWM techniques for single-phase five level cascaded H-bridge FPGA controller-based

2016

This paper presents an overview and experimental analysis of the MC SPWM techniques for single-phase cascaded H-bridge inverter. The multilevel power converters are an alternative to traditional converters known as “three-level converters”. The voltage waveforms and the related frequency spectra, which have been obtained by simulation analysis in Matlab-Simulink environment, are here reported for all the proposed modulation techniques. The simulation results have been experimentally validated through means of a DC/AC, five-level, single-phase converter prototype with an appropriate test bench.

CIGS PV Module Characteristic Curves Under Chemical Composition and Thickness Variations

2014

This paper analyzes how the electrical characteristics of a CIGS photovoltaic module are affected by the chemical composition and by the thickness variations of the CIGS absorber. The electrical characteristics here considered are the short circuit current, the open circuit voltage, the efficiency and the power peak. The chemical composition is varied by tuning the ratio between gallium and indium. This analysis has been performed by means of the wxAMPS software, developed by the University of Illinois. The above variations have been taken into account on a PV module made of 72 cells. This analysis has been carried out employing a PV module mathematical model developed and implemented by th…

Practical Implementation of a Synchronous PWM Strategy for Low Switching Frequency FOC of im Drives with ATSAM3X8E Microcontroller

2021

This paper presents a practical implementation of synchronous PWM modulation algorithm for an induction motor field oriented control powered by a DC/AC inverter and implemented on a low-cost microcontroller, the ATSAM3X8E. In particular, a simple algorithm, capable to calculate automatically an optimized set of frequency modulation indexes will be presented. Hysteresis bands are also introduced in the algorithm in order to avoid multiple changeovers during modulation index transitions. Experimental tests and their results will be shown and discussed, highlighting the benefits of the present algorithm, such as reduction of current harmonic content, reduction of current ripple and, consequent…

Implementation and experimental validation of a real-time PWM algorithm based on B-Spline carriers for three phase voltage source inverters

2009

This paper presents the implementation and experimental results of an algebraic real-time sinusoidal pulse width modulation algorithm (SPWM) based on B-Spline carriers. B-spline functions are used as carrier signals with the aim to to reduce harmonic content of the three phase inverter output voltage. The presented algorithm eliminates the problem of B-spline recursive evaluation with convolution integrals or convolution sums in digital counterpart. The pulse pattern synthesis is made with the help pre-calculated duty cycle expressions. In this way there is no real need to synthesize the carrier signal so the hardware and the whole inverter control system becomes cheaper, more reliable and …

Technical and economical comparison between NdFeB and hard ferrites linear electrical generators from sea waves

2015

In this paper the authors perform a technical-economic comparison of two different Tubular Permanent Magnet Linear Machines for sea waves generation by using finite elements analysis. The first configuration includes ferrite rings while the second configuration includes neodymium-iron-boron rings. In order to compare the two types in economic and technical terms, a detailed analysis of the main figures of merit of the two configurations has been carried out. In particular, significant data such as flux distribution, rated voltage and current, axial force, electric power, realization cost and maintenance cost have been compared.

Electric Mobility in Portugal: Current Situation and Forecasts for Fuel Cell Vehicles

2021

In recent years, the growing concern for air quality has led to the development of sustainable vehicles to replace conventional internal combustion engine (ICE) vehicles. Currently, the most widespread technology in Europe and Portugal is that of Battery Electric Vehicles (BEV) or plug‐in HEV (PHEV) electric cars, but hydrogen‐based transport has also shown significant growth in the commercialization of Fuel Cell Electric Vehicles (FCEV) and in the development of new infrastructural schemes. In the current panorama of EV, particular attention should be paid to hydrogen technology, i.e., FCEVs, which is potentially a valid alternative to BEVs and can also be hybrid (FCHEV) and plug‐in hybrid…

Dynamics photovoltaic generators: Technical aspects and economical valuation

2010

The strategy adopted from many European nations and not, to entrust the electric energy production to differently energetic sources has determined an increment of the scientific research for the solar resource exploitation. These scientific community activities follows with attention from the entrepreneurial world have concentrated on the innovative techniques and methodologies of the source conversion, solar concentration and the direction's device optimization. This job focuses its attention on the simple application of solar-track device, based on consolidated technologies. The diffused application of these dispositive, could be, shortly, an important increment of electricity generation …

Graphical THD minimization procedure for single phase five-level converters

2017

This paper proposes two graphycal procedure to mitigate h harmonics and to minimize the total harmonic distortion (THD), respectively. The paper considers a five-level inverter and fundamental frequency modulation: it computes the two switching angles able to reduce low order harmonics and able to minimize the THD. Simulation results are obtained and, in order to validate the proposed procedure, an experimental prototype is built and experimental results are carried out. The comparison between simulation and experimental results confirms the accuracy of the proposed graphycal procedure. It is shown that the switching angles to mitigate the third-fifth and the third-fifth-seventh harmonics e…

Contributed Review: Review of thermal methods for space charge measurement.

2016

The space charge accumulation phenomenon has garnered great interest over the last two decades because of the increased use of direct current in high voltage electrical systems. In this context, a significant relevance has been achieved by the thermal methods, used for solid dielectrics. This paper presents a review of this non-destructive measurement system used for the measurement of space charge. The thermal pulse method, the thermal step method, and the laser intensity modulation method are described. For each configuration, the principle of operation, the thicknesses analyzed, and the spatial resolution are described, reporting also the main related applications

Investigation of motor current signature and vibration analysis for diagnosing rotor broken bars in double cage induction motors

2012

This paper investigates the detectability of rotor broken bars in double cage induction motors using current signature and vibration analysis techniques. Double cage induction motors are commonly used for applications where successive loaded starts-up are mandatory. Experimental results were performed under healthy and faulty cases, and for different load conditions using each technique. Rotor broken bars fault detection based on sideband current components may fails due to the presence of inter bar currents that reduce the degree of rotor asymmetry, yielding to a decrease of the magnitude of these spectral components. But inter bar currents produce core vibrations in the axial direction, w…

Design of Soft Ferrite filters for EMI reduction in Power Conversion Systems

2019

The use of a discrete passive filter is the most attractive solution for EMI reduction in power conversion systems. This is due to its simplicity of concept and efficiency in the frequency range up to tens of megahertz and over. The common mode and differential mode sections of the EMI filter contain capacitors and soft magnetic chokes and, when they are used in the transportation context, their design has to satisfy further constraints in terms of low weight, low volume, low losses and low cost in adjoint to filtering efficiency. In this framework the authors, by using an EMI filter design procedure already setup by themselves, investigate, also with an experimental setup, the possibility …

Analytical Investigation and Control System Set-up of Medium Scale PV Plants for Power Flow Management

2012

In the field of photovoltaic (PV) plants and energy conversion from renewable sources, a large part of the technical literature is more devoted to practical aspects (new solar cells, electrically driven PV panels, safety, reduction of parasitic currents, etc.) than to theoretical investigations. Despite this tendency, this paper presents a mathematical analysis of a medium scale photovoltaic power generation system connected to the distribution network and of its control system. In such a system, the conversion stage is unique due to the absence of a boost chopper. The conducted analysis leads to the interesting conclusion that the inverter used in the plant presents two degrees of freedom,…

A software for the evaluation of winding factor harmonic distribution in high efficiency electrical motors and generators

2013

In this paper a software developed for the determination of winding connections, the calculation of winding factors and the evaluation of their harmonic distribution of three and two phase windings is presented by using as input data simply the number of slots, pole pairs and phases. The software is implemented as a function in MATLAB environment. By means of some examples, covering the most relevant winding types, the capabilities of this software will be shown. Particularly, integer and fractional single and double layer winding can be treated. Some examples are presented and briefly discussed. The connections, the winding factor harmonic distribution, the electro-motive force (e.m.f) THD…

Android tool to evaluate grounding resistance

2015

In the absence of sources of rapidly varying field, the study of the potential distribution determined, in a linear medium, by a geometrically complex grounding may be conducted by applying the method of superposition of the effects, known as method of subareas of Maxwell. Such approach can be usefully employed in an educational tool intended for students of electrical engineering.

Partial discharges on IGBT modules: Are sinusoidal waveforms sufficient to evaluate behavior?

2014

In recent years, the increasing use of AC-DC converters, especially in the field of renewable energy sources has led to the implementation of new modulation techniques, in particular the ones based on the pulse width modulation. The purpose of the present work is to verify the different behavior that is obtained when the components are subjected to the partial discharge test carried out with a sinusoidal waveform, and when they are subjected to PWM stress-type, similar to the actual signal generated by this type of electronic components. By considering equal rms value of the fundamental sine wave, the comparison has shown different partial discharges patterns.

Self training and meta-cognition goals. New approaches, trends and tools in modern teaching of power electronics

2016

Teaching a complex discipline like power electronics is an open question and the best educational approach or the objectives to be achieved at the end of a power electronic course are still in debate. This paper presents a visual didactic approach chosen by the Authors in the last years in their respective courses in power electronics. It also discuss the objectives and the skills required to the students at the end of the course: in particular, some meta-cognition objectives recently fully entered into the education world in general. Such meta-cognition goals are now discussed for the particular case of power electronics courses. The Switching Functions (SFs) generalized approach is then d…

Enhanced Mathematical Modelling of Interior Permanent Magnet Synchronous Machine Considering Saturation, Cross-Coupling and Spatial Harmonics effects

2020

The Interior Permanent Magnet Synchronous machine (IPMSM) conventional mathematical model is generally employed to investigate and simulate the IPMSM control and drive system behaviour. However, magnetic nonlinearities and spatial harmonics have a substantial influence on the IPMSM electromagnetic behaviour and performances. In order to simulate the IPMSM real electromagnetic behaviour, this paper describes an enhanced mathematical model that takes into account the saturation, cross-coupling and spatial harmonics effects. This model has been implemented in Matlab®/Simulink environment where the electric and magnetic parameters are derived from FEA investigations and implemented by the use o…

Experimental characterization of a proton exchange membrane fuel-cell for hybrid electric pedal assisted cycles

2017

This paper presents a feasibility study on the prototyping of a hybrid EPAC (Electric Pedal Assisted Cycle) through an FC-B-UC (Fuel Cell — Battery — Ultra-Capacitors) power system. Aim of this work is the characterization of a PEMFC (Proton Exchange Membrane Fuel Cell) in order to confirm its theoretical performances and to verify the possibility of its installation on an e-bike.

Experimental Comparison of Efficiency Enhancement Algorithms for Three-Phase Induction Motors

2019

This paper presents an experimental comparison of two efficiency improvement algorithms for three-phase induction motors by adopting Loss Model Algorithms (LMAs). The efficiency enhancement is evaluated starting from several simulations for different conditions of load and speed and, then, validated by comparing the experimental results obtained by applying the two control strategies and the traditional Field Oriented Control (FOC). Significant results in terms of efficiency enhancement are presented and discussed.

Algebraic real-time algorithm for B-Spline sinusoidal pulse width modulation in three phase voltage source inverters.

2008

In this paper a novel algebraic real-time algorithm for implementation of sinusoidal pulse width modulation (SPWM) based on B-spline carriers is introduced and discussed. B-spline functions are used as carrier signals with the aim to to reduce harmonic content of the three phase inverter output voltage. This algorithm eliminates the problem of B-spline recursive evaluation with convolution integrals or convolution sums in digital counterpart. The pulse pattern synthesis is made with the help pre-calculated duty cycle expressions. In this way the carrier signals have not to be really synthesized, hence the hardware and the whole inverter control system becomes cheaper, more reliable and affo…

Comparison on the use of PV systems in the vertical walls

2015

In this article the preliminary evaluation of the performance of a photovoltaic window is presented. The aim is to trace the behavior of next-generation systems, which favor architectonical integration. Three different systems have been taken into account: a dye sensitized solar cell (DSSC), blue and grey caved silicon panels. The systems can be placed behind a window or behind a wall of glass blocks.

Computer Aided Optimization Via Simulation Tools of Energy Generation Systems With Universal Small Wind Turbines

2012

This paper considers the general issues in the project and the optimization of energy generation systems using small universal wind turbines, suitable in Distributed Generation (DG) and computer aided optimization for a better exploitation of wind source. Optimization in this field reveal to be more and more important because the local generation and consumption of electrical power, even for grid connected generators can suffers for unevenness of wind source exploitation, also in terms of wrong directions and in not regular wind flows. Computer aided design and optimization of small plants may give significant improvements in the development of the wind source also in accordance with the pr…

Analysis a DSP Implementation and Experimental Validation of a Loss Minimization Algorithm Applied to Permanent Magnet Synchronous Motor Drives

2004

In this paper a new loss minimization control algorithm for inverter-fed permanent-magnet synchronous motors (PMSM), which allows to reduce the power losses of the electric drive without penalty on its dynamic performances, is analyzed, experimentally realized and validated. In particular, after a brief recall of two loss minimization control strategies (the "search control" and the "loss-model control"), both a modified dynamic model of the PMSM, which takes into account the iron losses, and a "loss-model" control strategy, are treated. Experimental tests on a specific PMSM drive employing the proposed loss minimization algorithm were performed aiming to validate the actual implementation.…

Diagnosis of mechanical unbalance for double cage induction motor load in time-varying conditions based on motor vibration signature analysis

2013

This paper investigates the detectability of mechanical unbalance in double cage induction motor load using motor vibration signature analysis technique. Rotor imbalances induce specific harmonic components in electrical, electromagnetical, and mechanical quantities. Harmonic components characteristic of this category of rotor faults, issued from vibration signals analysis, are closely related to rotating speed of the rotor, which complicates its detection under non-stationary operating conditions of the motor. Firstly, experimental results were performed first under healthy and mechanical load unbalance cases, for different load levels under steady-state operating conditions to evaluate th…

Demand side management and Distributed on Site actions benefits

2013

Global warming and energy demand are nowadays becoming one of the major issues of the third millennium, mainly because human activities seem to have a clear impact on the raise of CO2 emissions as never it has been experienced in the past. Among the different factors affecting CO2 emissions, energy demand from buildings constitutes one of the most important actors. Energy Management (EM) actions can reduce the energy consumption of the system and minimize peaks-level, by using a distributed control over every house. These local actions can greatly contribute to reduce the impact on the global CO2 emissions. An evaluation of the potential energy saving and CO2 emissions reduction on building…

A review of fuel cell based hybrid power supply architectures and algorithms for household appliances

2014

Abstract Nowadays, renewable power system solutions are widely investigated for residential applications. Grid-connected systems including energy storage elements are designed. Advanced research is actually focused on improving the reliability and energy density of renewable systems reducing the whole utility cost. Source and load modeling, power architectures and algorithms are only a few topics to be addressed. Designers have to carefully deal with each subtopic prior to design efficient renewable energy systems. In the literature, each topic is separately discussed and the lack of a unique reference guide is clear to power electronics designers. In this paper, each design step including …

Monitoring and Diagnosis of Failures in Squirrel-Cage Induction Motors Due to Cracked or Broken Bars

2011

In this paper three diagnostic procedures, based on on the vibration, current and instantaneous power monitoring for the detection and monitoring of incipient faults as cracks or bar breaks on squirrel cage motors are briefly reminded. The experimental investigations, carried out at the SDESLab (Sustainable Development Energy Savings Laboratory) of the University of Palermo in order to underline merits and drawbacks of the methods applied to the same die cast squirrel cage induction motor, are presented. The results of the investigations confirmed the effectiveness of the diagnostic procedures here considered.

Reducing DC Link Voltage Unbalance in a Fault-Tolerant Inverter

2014

Today, continuous working of power inverter drives is mandatory for several applications. Damages to materials, machines or even risks to human life have to be absolutely avoided. In the literature, fault-tolerant algorithms and architectures to achieve a successful fault handling are investigated. Researchers aim at reducing the number and cost of additional components, improving at the same time the inverter performances under postfault conditions. Cost, post-fault power derating and increasing distortion are usually conflicting requirements. In this paper, a fault-tolerant three phase inverter is presented. A reconfigurable architecture and a novel fault-tolerant algorithm is designed to…

Electrical characterization of highefficiency bifacial silicon solar cells

2018

This work presents a preliminary study on the electrical characterization of high efficiency bifacial solar cells. An opening discussion on the state-of-the-art of such advanced technology is initially proposed and the experimental characterization of some prototypes is described. From this analysis, it can be stated that the bifacial silicon solar cells can be a very promising technology with high electrical performances and efficiency.

Rainfall energy harvester

2015

This chapter provides a detailed study on the harvest of the energy contained in raindrops by means of piezoelectric transducers. The energy harvester has the role of an electric source, able to recharge storage devices of small electronic components, such wireless sensors, by using the vibrational energy released by the drops hitting the transducer, reducing in such a way the chemical waste of conventional batteries. In technical literature, diverse studies agree on the level of suitable generated voltage on the electrodes of a piezoelectric transducer subjected to rainfall, but a complete characterization on the supplied power is still missing. This work, also to limit optimistic forecast…

A back to back method for the temperature rise test of prefabricated substations: A case study

2015

In this work a back to back method is presented which allows to develop heating tests of prefabricated secondary substations with a limited number of supplying equipment (an induction regulator and a capacitor bank). The proposed method makes use of the transformer tap changers to create a voltage difference on the medium voltage side. In this way, only an adjunctive low voltage supply is needed. With the proposed test system, the heating tests are developed on a 1000 kVA prefabricated substation. Thanks to the experimental tests, the class of enclosure of the substation and the operating temperature and resistance of the power transformers are determined, according to the recommendations o…

A Perspective on the Future of Distribution: Smart Grids, State of the Art, Benefits and Research Plans

2013

Currently, the design and operation criteria for electrical distribution networks are fastly changing due to some factors; among these, the progressive penetration of Distributed Generation (DG) is destined to cause deep changes in the existing networks, no longer considered as passive terminations of the whole electrical system. Moreover, the increasing application of Information Communication Technologies (ICT) will allow the implementation of the so called “smart grids”, determining new interesting scenarios. In the paper the problems and the potential benefits of DG, the possible new electrical distribution system models and the major research projects on smart grids are faced and repor…

A DC-DC power converter for PV module characterization

2014

In this paper, a standard-compliant electronic load setup for PV module curve detection which features high accuracy, low cost and components count is proposed. The proposed device is based on a DC-DC power converter in open-loop configuration. The proposed system is designed according to regulation constraints in order to achieve high performances in curve detection. Design criteria are discussed. The model is implemented in PSIM environment. Simulation based on data input of a commercial PV Conergy E215P module are carried out under several environmental conditions to show the accuracy of the proposed electronic load. Simulation results are reported.

A measurement setup for electric bicycles powered from renewable energy sources

2014

In this paper a measurement system for a pedalassist rickshaw is described. It has been designed and realized with the purpose of a deep analysis of operating time, range and general performance of the prototype vehicle. The three-wheel velocipede under test, developed in the SDES laboratory of the University of Palermo, is equipped with two battery packs, and a photovoltaic panel which is used to recharge one of the packs at a time. To further improve the autonomy of this mean, a fuel cell will be added as a power source, whose consequent improvement in performance could be easily investigated by the presented measurement setup. An Arduino board has been employed to receive and store all c…

Parametrical study of multilayer structures for CIGS solar cells

2014

In this paper, a numerical analysis of relevant electrical parameters of multilayer structures for CIGS-based solar cells was carried out, employing the simulation software wxAMPS. In particular, we have focused on thin film cells having a ZnO:Al/ZnO/CdS/CIGS structure with a Molybdenum back contact. The aim of this work is to establish good theoretical reference values for an ongoing experimental activity, where our technology of choice is the single-step electrodeposition. In detail, we have analyzed how the main electrical properties change with the bang gap and the thickness of the absorber layer, for such a type of solar cell structure. Our results show that both efficiency and fill fa…

Economie assessments on the use of wired and wireless recharging systems in Italian and European market

2017

The conductive charging method for the electric vehicles is the most widespread, since it is the simplest and has higher returns. In the last years, alternative charging technologies have been investigated. Between these wireless charging systems have been large diffusion and have been commercialized by some manufacturer. Wireless charging systems for electric vehicles have some advantages respect the wired ones, not obliging the user to connect physically the vehicle to the electric charging station. Assuming the efficiency declared by the manufacturer of wireless systems the authors, in this paper, estimate the maximum cost that wireless recharging systems can have to be, however, more fa…

Recharge stations: A review

2016

Charging equipment for all-Electric Vehicles (EVs) is classified by the rate at which the batteries are charged. Charging times vary based on how depleted the battery is, how much energy it holds, the type of battery, and the type of Electric Vehicle Supply Equipment (EVSE). In this paper, a review of the innovative charging stations is reported.

Electric and magnetic emission in near field region and thermal behaviour of power module for photovoltaic application

2015

The new power module, characterized by high power density, miniaturization of packages and layout and high frequency switching, are increasingly used in the field of in automotive, aircraft industry and for Distributed Generation (DG) connected to smart grid. To guarantee the reliability and safety of these systems, the electromagnetic compatibility (EMC) and thermal behavior, have to be carefully considered for these appliances. This paper describes a measurement methodology to characterize the electromagnetic emissions in near field zone produced by a PM prototype and its thermal behavior. In particular, the electric and magnetic fields, in the near field region in the frequency range 9kH…

A General Mathematical Model for non-Redundant Fault-Tolerant Inverters

2011

Industrial systems able to release trusted services is an integrated concept that resumes the attributes of availability, reliability, safety, integrity, and maintainability. In power electronics this can be aimed via the introduction of fault tolerant architectures. While In the past technical literature the mathematical modeling problem for non-redundant converters was fronted studying separately the cases of fault leg by leg, in this paper a general model able to include the three possible cases of leg faults with a unique set of equation is introduced and discussed. The same model allows to evaluate the DC Link transient and steady state evolution and also allows to develop with much ea…

Wireless Power Transmission for house appliances: A small-scale resonant coupling prototype

2016

This paper presents a low cost prototype of wireless power transfer system based on resonant coupling. The system here proposed can be useful for house appliances battery charging systems: as a matter of fact, it consists mainly of two copper wire coils or windings, placed one in front of the other on the same axis. By exploiting the coils resonance coupling effect, electric energy can be transferred from the inductor coil to the receiver in order to charge the batteries. Low cost experimental tests demonstrated the effectiveness of the proposed wireless power transfer prototype, being it capable to reach an efficiency of about 80% and more along a distance of 30 cm.

Anomalous electrical parameters improvement in Ruthenium DSSC

2018

. In this work, we present a series of measurements carried out on Ruthenium-based Dye Sensitized Solar Cells (DSSCs) after the application of different external electrical field values. Such measurements have been performed both in the dark and by illuminating the sample with sunlight emitted by a solar simulator (AM1.5G spectrum with a power irradiance of 1000 W/m2). Our results demonstrate that the initial electrical bias field modifies in both cases the behavior of the cell in terms of an anomalous improvement of the main electrical parameters.

Modified Modulation Techniques for Quasi-Z-Source Cascaded H-Bridge Inverters

2018

Quasi-Z-source cascaded H-bridge (q Z S - C H B) inverters are one promising solution for high power photovoltaic (PV) systems. This type of topologies inherits the advantages of cascaded converters (i.e., multilevel outputs) and impedance-source inverters (i.e., high conversion ratios). In addition, it allows increasing the inverter reliability (with high redundancy). However, the modulation and control of qZS-CHB inverters are challenging to a certain extent. Thus, this paper proposes modified modulation techniques to increase the performances of qZS-CHB converters in terms of voltage gains and stresses. The novelty lies in the use of the switching frequency optimal as reference signals i…

A Novel Computational Approach for Harmonic Mitigation in PV Systems with Single-Phase Five-Level CHBMI

2018

In this paper, a novel approach to low order harmonic mitigation in fundamental switching frequency modulation is proposed for high power photovoltaic (PV) applications, without trying to solve the cumbersome non-linear transcendental equations. The proposed method allows for mitigation of the first-five harmonics (third, fifth, seventh, ninth, and eleventh harmonics), to reduce the complexity of the required procedure and to allocate few computational resource in the Field Programmable Gate Array (FPGA) based control board. Therefore, the voltage waveform taken into account is different respect traditional voltage waveform. The same concept, known as “voltage cancelation”, used for single-…

Experimental test on a Contactless Power Transfer system

2014

Contactless Power Transfer (CPT) is an ever-growing technology in automotive market, due to the significant improvement brought by it to battery charging operation in terms of safety and comfort. CPT is based on inductive coupling between two coils, so that power cords can be avoided for vehicles battery charging and an important contribution towards a smarter mobility can arise. In this paper, a CPT prototype for E-bike is proposed. Magnetic design and power electronics system are described. Experimental results deriving from laboratory tests are presented and power efficiency of the system is addressed.

Sliding mode torque control of an induction motor for automotive application with sliding mode flux observer

2016

In this paper, the performance of two control systems of induction motors for automotive applications were compared in order to highlight the differences in terms of response speed, robustness and noise immunity. The first system is realized through a field-oriented control with PI controllers, while the second system is realized through a field-oriented control with Sliding Mode Controllers. Both controls are designed to follow the torque references as required for the vehicles and are tested with typical load profiles of vehicles. It also designed a sliding mode observer flux.

Stability of Microgrids: An Application of Virtual Synchronous Generator

2022

The objective of this paper is to illustrate an alternative control algorithm for power converters which have the task of introducing the energy generated by systems based on the use of renewable sources such as, photovoltaic or wind power, in to small-sized networks, microgrids. Virtual Synchronous Generator can operate both in parallel to the main network as well as in isolated and autonomous conditions (islanding-mode). The contribute of this work is to drive a consolidate approach, made in time domain, in a more flexible and less time-consuming approach based on Park transformation.

Enhanced loss model algorithm for interior permanent magnet synchronous machines

2017

This paper presents an experimental study on the impact of the parameter variations over the performances of a LMA (Loss Model Algorithm) designed for an IPMSM (Interior Permanent Magnet Synchronous Machine). In a previous work, the characterization was carried out by assessing, for several working conditions, the motor parameters that influence the motor efficiency. The proposed enhanced loss model algorithm is implemented in a rapid prototyping system and its performances, in term of efficiency, are compared with other control systems, obtaining promising results.

Experimental study on efficiency enhancement in Interior Permanent Magnet Synchronous machines

2015

This paper presents an experimental study on the efficiency variation occurring in an IPMSM (Interior Permanent Magnet Synchronous Motor) with respect to the direct axis current component and for several working conditions. Such investigation is the starting point for the arrangement of a speed control drive system equipped with a real-time power losses minimization algorithm. More in detail, a test bench is set up to carry out the measurements needed for the final power loss identification. The experimental investigation is developed by performing tests at different speed, magnetization and load conditions. From the obtained results, it can be stated that the IPMSM efficiency can be maximi…

A cogging torque minimization procedure for IPMSMs based on different laminate geometry

2016

This paper presents a possible minimization procedure of the cogging torque generated by an IPMSM (Interior Permanent Magnet Synchronous Machine) with a progressive modification of a basic geometrical structure of rotor laminates. More in detail, an IPMSM model is analyzed by using a Finite Element Method (FEM) approach. Then, other IPMSM models, which are obtained by modifying the geometry of the IPMSM rotor laminates and by maintaining the same stator configuration, are proposed and discussed. From the obtained simulation results, the cogging torque components for each structure are determined by means of FEM and compared to each other. From this comparison, it can be stated that the cogg…

Integrated Mathematical Model of Proton Exchange Membrane Fuel Cell Stack (PEMFC) with Automotive Synchronous Electrical Power Drive

2008

In this work, the mathematical dynamical model of a PEMFC stack has been developed and implemented in Matlab environment. Lots of simulations have been executed in two different load conditions. Firstly with a resistive load and finally with a synchronous electrical power drive in automotive load conditions. The innovation in this field consists in the integration in PEMFC stack mathematical dynamic model of a synchronous electrical power drive one for automotive purposes. As regards the simulations with a synchronous electrical power drive, the complete mathematical model allows to evaluate the PEMFC stack performances and electrochemical efficiency. This represents a useful design tool.

Power management of a battery/supercapacitor system for E-mobility applications

2019

Hybrid Energy Storage Systems (HESS) have been very popular in recent years in different applications, from electric vehicles (EVs) to smart grids and renewable energies, due to the growing need to accumulate electricity. The concept of hybridization arises from the requirement of both high energy and specific power. The battery/supercapacitor (SC) system offers great advantages in a DC bus, giving the opportunity to provide high amounts of power to the loads. In this paper, a system composed of two bidirectional DC-DC converters, one connected to a battery pack and one to a stack of supercapacitors, is presented for a DC bus in electrical mobility (E-Mobility) applications. The proposed co…

Determination of differential leakage factors in electrical machines with non-symmetrical full and dead-coil windings

2017

In this paper Gorges polygons are used in conjunction with masses geometry to find an easy and affordable way to compute the differential leakage factor of non symmetrical full and dead coil winding. By following the traditional way, the use of the Ossanna's infinite series which has to be obviously truncated under the bound of a predetermined accuracy is mandatory. In the presented method no infinite series is instead required. An example is then shown and discussed to demonstrate practically the effectiveness of the proposed method.

Interior permanent magnet synchronous motors: Impact of the variability of the parameters on their efficiency

2016

In the scientific literature, various authors presented different control strategies aimed to increase the efficiency of the interior permanent magnet synchronous motors. These strategies, starting from a well-known mathematical model of the dynamic behaviour of the motor, are able to reduce the power losses acting on the magnetizing component of the stator current. However, none of the proposed approaches takes into account that, varying the working conditions of the motor, also the values of the parameters, which have an impact on the power losses, can vary. In this paper, therefore, starting from an accurate measurement of the motor characteristics for various values of speed and load, w…

Designing a Sustainable University Recharge Area for Electric Vehicles: Technical and Economic Analysis

2017

This article addresses the technical and economic challenges regarding the design of a “green” recharge area for electric vehicles at the University of Palermo in order to reduce costs and pollution connected to the charging process. Based on the behaviour of the student population, the electrical load is identified and two possible solutions are evaluated to manage the peak load: an orientation of the panels increasing the power at defined time and the use of a storage system. The main strength and weakness points of two systems are investigated by taking into account the Levelized Cost of Energy (LCOE), which reaches 75.3 €/MWh for the orientation of panel and 103 €/MWh for the storage sy…

A New Digital Demodulator for Sensorless Control of Electrical Drives with Permanent Magnet Synchronous Motors

2008

This paper deals a new digital demodulator algorithm for sensorless control of interior permanent magnet synchronous motors (IPMS) based on the estimation of speed and rotor angular position. To this aim a signal similar to that generated by a resolver connected to the shaft of the motor is obtained injecting high frequency stator currents. A new digital algorithm has been designed and set up to demodulate the above signal whose implementation can be carried out on the same DSP that processes the whole control algorithm. The proposed demodulator scheme is presented and justified on the theoretic point of view. Simulations results finally validate the effectiveness of the demodulator within …

Economic analysis on the use of wired and wireless recharging systems

2017

Wireless charging systems for electric vehicles have some advantages respect the wired ones, not obliging the user to connect physically the vehicle to the electric charging station. However, at the same time, they have disadvantages linked to issues of electromagnetic compatibility and low efficiency. This study considers some scenarios for which both wired and wireless recharging systems can be adopted, with the aim of estimate the efficiency that must be guaranteed by wireless systems, so that its realization could be more favorable with respect to wired one. The estimation is developed by means of classical economic indexes, in the framework of Italian end European markets. Results repo…

Flexible power converters for the fault tolerant operation of Micro-Grids

2010

The progressive penetration level of Distributed Generation (DG) is destined to cause deep changes in the existing distribution networks no longer considered as passive terminations of the whole electrical system. A possible solution is the realization of small networks, namely the Micro-Grids, reproducing in themselves the structure of the main production and distribution of the electrical energy system. In order to gain an adequate reliability level of the microgrids the individuation and the management of the faults with the goal of maintaining the micro-grid operation (fault tolerant operation) is quite important. In the present paper flexible power converters and a companion control al…

Economical Incentives and Systems of Certification for the Production of Electrical Energy from Renewable Energy Resources

2007

In order to succeed in observing the international agreements undertaken in the Kyoto agreement protocol, today it is necessary to increase the electrical energy production from renewables energy resources (RERs). In this paper a complete description of the Italian incentive systems for the production of electrical energy from photovoltaic (PV) and other RERs is done. Moreover, some considerations about the effects of the incentive actions on the wide spread of RERs to produce electrical energy are reported; particular attention is paid in the economical analysis related to PY and wind systems.

Modelling, simulation and characterization of a supercapacitor

2020

In the last decade, the issue of air pollution or the reduction of CO2 emissions has become of extreme interest both for civil society and then for the industrial and scientific research world. For this reason, the scientific research on automotive is called to answer with increasingly innovative solutions. One of the principal subjects are the storage and the utilization of the electric energy for electrical and hybrid vehicles. Nowadays, supercapacitors are getting more and more attention because of their characteristics that allow them to be a bridge between electrolytic capacitors and batteries in several application such as bust-mode energy delivery, regenerative breaks and so on. The …

Wireless battery charging: E-bike application

2013

Nowadays, Inductive Power Transfer (IPT) represents a widely investigated issue with respect to modern battery charging methods, by providing a wireless solution. IPT is applied across a large variety of applications, from Watt to kWatt power levels. Although IPT features great benefits in terms of safety and comfort, the most significant drawback consists of a relatively poor power conversion efficiency. In this paper, a 100W wireless charging equipment for E-bikes which improves efficiency is proposed. Complete magnetic structure design, as well as transmitter and receiver efficient architectures, are deeply exposed. The efficiency of the designed solution is shown by simulation results.

Inductive Power Transfer for 100W battery charging

2013

Today, Inductive Power Transfer (IPT) is widely investigated to provide wireless battery charge. Potential applications range from a few Watts of handheld devices to kWatts of automotive applications. Despite of comfort and safety options, wireless charging features relatively poor power conversion efficiency. In the literature, several solutions are proposed addressing efficiency related issues. In this paper, a 100W wireless charging station for electric bikes which improves the power conversion efficiency is proposed. The magnetic structure design is analyzed thoroughly as well as the proposed power electronics system architectures of both the power transmitter and power receiver. The ef…

A Bidirectional IPT system for Electrical Bicycle Contactless Energy Transfer

2019

Contactless Energy Transfer characterized by Inductive Power Transfer (IPT) is a viable solution for Electric Vehicle (EV) battery charging, giving advantages in terms of safety, comfort and automatism of the recharging operation. IPT is a smart option for the Vehicle- To-Grid (V2G) implementation as well: the EV's battery can provide power to other users, if possible and if required, in order to adequately respond to an active demand scenario. IPT shall therefore allow a Bidirectional power flow, so that it can be properly defined as Bidirectional IPT (BIPT). In this paper, a 300 W BIPT system for E-bikes is proposed and experimental results are shown as well. Considering power level and s…

Recursive Selective Harmonic Elimination for Multilevel Inverters: Mathematical Formulation and Experimental Validation

2023

A recursive method that eliminates +1 harmonics and their respective multiples from the output voltage of a cascaded H-bridge multilevel inverters with = 2 dc sources ( = 1, 2, 3,...) is proposed. It solves 2×2 linear systems with not singular matrices and always gives an exact solution with very low computational effort. Simulated results in three-phase five, nine, seventeen and thirty three level CHB inverters, and experimental results in five-level inverter demonstrate the validity of the method.

A standard-compliant prototype for PV module curve detection

2014

In this paper, a prototype for PV module curve detection which features low cost and size and ensures high accuracy is proposed. The proposed architecture is based on a buck-boost converter in open-loop configuration. The proposed architecture is fully compliant with actual standard IEC60904. The duty-cycle control algorithm and its own effects on system performances are accurately investigated. The comparison of different duty-cycle patterns is carried out and performance evaluation is performed. Simulation results are shown to perform a valuable comparison of control algorithms. Preliminary experimental results on a laboratory prototype are presented.

From electric mobility to hydrogen mobility: current state and possible future expansions

2020

The expansion of electric vehicles in Italy, has already started a few years ago, but some aspects prevent its expansion. Currently users prefer hybrid technology, mainly due to socio-economic factors related to initial investment and anxiety about autonomy. The aim of the document is to understand if the adoption of Fuel Cell technology can be a solution to overcome the problems of environmental pollution. The possibility to be able to use fuel cells to store electricity is very advantageous, especially on charging times that are significantly reduced. Based on the current situation and analyzing the available data, this work reports the current state of electric mobility in Italy and trie…

Digital demodulation for fast set-up of sensorless PMSM electrical drives based on magnetic anisotropy

2009

This paper presents a demodulation algorithm applied to the sensorless control of permanent magnet synchronous motors (PMSM). The sensorless control technique reported in this paper is based on the injection of high frequency voltages to the stator so that the motor currents contain information on the rotor position. This information is then extracted by an appropriate demodulation technique. The presented demodulation algorithm is based on spectral analysis of the signal produced by the sensorless control technique because this is fully characterized and presents not ambiguous correlation between current harmonic content and rotor position. The most important feature of the demodulation al…

Enhanced flexible algorithm for the optimization of slot filling factors in electrical machines †

2020

The continuous development in the field of industrial automation and electric mobility has led to the need for more efficient electrical machines with a high power density. The improvement of electrical machines’ slot filling factors is one of the measures to satisfy these requirements. In recent years, this topic has aroused greater interest in the industrial sector, since the evolution of the winding technological manufacturing processes allows an economically sustainable realization of ordered winding arrangements, rather than random ones. Moreover, the manufacture of electrical machines’ windings must be preceded by an accurate design phase in which it is possible to evaluate the maximu…

Main Fuel Cells mathematical models: Comparison and analysis in terms of free parameters

2010

This paper resumes the main mathematical models of Fuel Cells (PEM models). In particular, a comparison study of the various models introduced in the technical literature is presented and the dependency of the various model parameters is analyzed in different operating conditions. As the manifold of the model parameter is very wide and their determination is difficult, it is mandatory to introduce approximations and simplifications on which each model is based. The novelty of this work is the organization of the existing models in three categories with regard to the number of free parameters and to the dependency of such parameters on the different running conditions and the usage of a refe…

Economical evaluation of ecological benefits of the demand side management

2014

Environmental pollution and over-exploitation of non-renewable sources to find energy are current topics for the modern world that is now at having to deal with several issues such as the greenhouse effect, acid rain and climate change. In this study, the economical estimate of the savings in carbon dioxide obtained with a careful management of electrical loads is presented. Four particular scenarios are designed as case studies: Italy, France, United Kingdom and Germany. A comparison is presented with a similar study, made in 2007, when green energies were not yet very developed.

Test Bench Realization and Application of Specific Working Cycles for the Characterization of Wheelchair Electrical Drives

2006

The life quality of motion disabled people is increased by the use of more and more sophisticated electrical wheelchairs. Despite the diffusion of such aid tools, specific technical standards for the determination of characteristic parameters of their electric drives are not so developed as the ones available for urban electric vehicles. In this paper, in order to define new technical standards for wheelchairs electrical drives, a wheelchair test bench has been purposely carried out. Moreover two specific working cycles, previously conceived and defined by some of the Authors to characterize the performances of the propulsion systems suitable for electrical wheelchair applications, have bee…

A Small Power Transmission Prototype for Electric Vehicle Wireless Battery Charge Applications

2012

In this paper a low cost prototype of wireless power transfer system based on air coupling is presented. The system here proposed can be useful for electric vehicle (EV) battery charging systems. It consists mainly of two copper wire coils, placed one in front of the other on the same axis. The inductor coil can easily be placed under the road surface (in a parking), while the other (the receiver coil) in the lower side of the vehicle. By exploiting the coils resonance coupling effect, electric energy can be transferred from the inductor coil to the receiver in order to charge the batteries. Low cost experimental tests carried out at DIEETCAM - University of Palermo, demonstrated the effect…

Experimental characterization and comparison of TLIM performances with different primary winding connections

2017

Abstract This paper presents an experimental characterization and comparison of the performances achieved by a Tubular Linear Induction Motor (TLIM) prototype with different typologies of primary winding connections. More in detail, three different configurations have been considered, analyzed and discussed: full-pitch star, 5/6 shortened pitch star and 5/6 shortened pitch double star. For this purpose, an experimental test bench at the Sustainable Development and Energy Saving Laboratory (SDESLab), University of Palermo, Italy, has been set-up. The obtained results have allowed the identification of the best winding configuration for different applications intended for the motor. Moreover,…

A 9-level three-phase multilevel converter with harmonic mitigation and integrated battery balancing

2019

In this paper, a 9 level three-phase multilevel converter with a harmonic mitigation control method and an integrated battery balancing algorithm for automotive purpose is proposed. Each level of the converter is composed by a buck-boost converter and an h-bridge in cascaded connection. The control algorithm is implemented to achieve the harmonic mitigation on the output voltage waveform and to maintain the battery input voltages balanced. The design and operation of the system is described, and simulation study is reported using Matlab/Simulink platform.

A comparison of different DC-DC converters for energy storage management in nearly-Zero Energy Buildings

2020

In the recent years, there has been a notable interest towards renewable sources, energy saving and efficiency optimization, in order to reduce the damages brought by fine dust and greenhouse gases in terms of safety, health and environmental protection. In the building sector renewable sources and energy efficiency optimization are leading to a large scale employment of nearly-Zero Energy Buildings (n-ZEBs), meaning that the balance between produced and required energy is negligible. For a proper n-ZEB implementation, a power system architecture has to be accurately designed, according to the existing renewable sources, loads and storage systems. In this paper, an investigation on differen…

Batteries for Aerospace: A Brief Review

2018

This paper presents a brief overview on batteries for aerospace application. In particular, More Electric Aircraft (MEA) and All Electric Aircraft (AEA) concepts are introduced at first, together with their main advantages and drawbacks. Subsequently, opportunities and issues related to the employment of batteries on aircrafts are presented and briefly discussed. Reference is then made to aircraft power system architectures and battery technologies, as well as on the state-of-the-art of battery management systems, state-of-charge and state-of-health estimations, and thermal management.

Economic evaluation on the use of reconfiguration systems for increase of energy production in PV plants

2016

This paper presents an economic analysis of the effectiveness of Dynamic Reconfiguration Systems (DRS) for PV plants in dependence of the incentive policies offered by several countries of the European Community. This evaluation has been achieved by means of the NPV (Net Present Value) and through the comparison between Bulgaria, Romania, Greece and Croatia. From the obtained results, it can be stated that the adoption of reconfiguration systems, in certain cases, can be a convenient solution.

Electromagnetic Full-Wave Simulation of Partial Discharge Detection in High Voltage AC Cables

2019

Partial discharge (PD) activity in the insulation system of an electrical equipment can determine the failure of the whole apparatus. PD sensors are widely used in high-voltage electrical systems as the main elements of a detecting system oriented to real time monitoring. Recently, non-invasive sensors have been proposed in industrial applications for cable and other sensitive electrical parts: they are based both on capacitive and on the electromagnetic radiating coupling. In order to assess the real performance of a new sensor produced by a high voltage AC cables manufacturer, the paper proposes electromagnetic fullwave simulation results.

Experimental Validation of a Novel Method for Harmonic Mitigation for a Three-Phase Five-Level Cascaded H-Bridges Inverter

2019

In modern high-power electrical drives, the efficiency of the system is a crucial constraint. Moreover, the efficiency of power converters plays a fundamental role in modern applications requiring also a limited weight, such as the electric vehicles and novel more electric aircraft. The reduction of losses pushes for systems with a dc bus and a high number of dc/ac converters, widespread in the vehicle, not burdened by a too expensive data processing system. The purpose of this article is to concur to reduce losses by proposing an innovative selective harmonic mitigation method based on the identification of the working areas where the reference harmonics present lower amplitudes. In partic…

An RF Wireless Power Transfer system to power battery-free devices for asset tracking

2019

Internet of Things (IoT) and Wireless Sensor Networks (WSN) infrastructures are becoming more and more available and diffused. One major outcome is the development of new services that help to make everyday life easier and better. One of those to which this paper reserves special attention is asset tracking which refers to the method of tracking physical assets. This service is very well based on IoT infrastructure and, due to the enormous number of objects to be traced, desperately needs the availability of inexpensive tags with sensing capabilities, that can be conveniently monitored from a long distance and require no maintenance. For this, engineers are called to face very challenging i…

Eletric vehicles impact using renewable energy

2015

In this moment, the principle topics for the modern world are the reduction of environmental pollution and the production of energy from renewable sources (for example photovoltaic system, wind farm, hydroelectric plants, etc.). This particular attention is determined by different reasons, in particular from the Kyoto Protocol, and from different problems as greenhouse effect, acid rain and climate change. The scope of this work is to study, for different years (1997-2013) in Italy, the production of electric energy from renewable and non-renewable. At a later stage, the attention will be on the consumption of the electric energy divided for different sectors. In particular, we study the po…

A unified observer for robust sensorless control of DC–DC converters

2017

Abstract Due to the large variety of converters' configurations, many different sensorless controllers are available in the literature, each one suited for a particular converter. The need for different configurations, especially on the same power supply, make it clear the advantage of having a shared control algorithm. This paper presents a unified nonlinear robust current observer for buck, boost and buck–boost converters in synchronous and asynchronous configurations. The unified observer speeds up the design, tuning and the implementation, and requires a memory cheaper code, easier to certify. Simulation and experimental results are presented to validate the approach in different scenar…

Design of a grid connected inverter for sustainable small wind farms

2016

The actual definition of sustainability is nowadays widely accepted. It provides a very general indication on what it is, but it reveals unable to assert how it should be reached. However, if one considers the multiplicity of human activities that have led to talk of real process of human settlement on the environment, it is then understood how it is close to the particular mankind activities. Then the task of providing a guidance on what to do within the sustainability concept is delegated case by case. In this paper, with reference to wind renewable source, The Authors give some indications in the design of a voltage source inverters aimed to optimal use of the wind source. In particular …

Harmonic reduction in CHB 13-level inverters by PAM fundamental-frequency strategy

2019

In this paper cascaded H-bridges (CHB) 13-level inverters are considered and a particular pulse amplitude modulation (PAM) strategy is introduced to mitigate or eliminate many harmonic components on the output voltage, in order to obtain low Total Harmonic Distortion (THD) factor. This procedure defines different dc voltage sources and sets of six switching angles, depending on an integer parameter $q$ belonging to the close interval $I=[11, 15]$ . The obtained THD doesn't depend on modulation index $m$ . The control of $m$ is made by changing the dc voltage sources that depend linearly on m, while the switching angles remain constant. An investigation about the role of the $q$ parameter on…

Energy Consumption/Generation Model: Data collected, architecture conceived and scenarios addressed

2014

The paper provides the data collected, the architecture and the conceived scenarios for the development of an Energy Consumptions/Generations Model. This model is suitable for the modeling, processing, analyzing and forecasting of energy consumption and generation at home, building and neighborhood level. Data are from the Census Returns, Electoral Registers & Council of the real town of Loughborough (U.K.). The architecture conceived describes the real distribution system which supplies the Loughborough geographic area. The scenarios considered take into account both traditional dwellings (equipped with dumb appliances) and new dwellings (equipped with smart networked appliances) © 2014 IE…

Efficiency Improvement of Inverter-Fed Permanent Magnet Synchronous Motors

2003

In this paper a control algorithm for the efficiency improvement of inverter-fed permanent magnet synchronous motors (PMSMs) is presented. The proposed algorithm allows reducing the losses of the drive without reduction of its dynamic performances. In details, after recalling a dynamic model of the PMSM, which has been purposely modified and that takes into account the iron losses, the basic equations and the constraints to obtain the loss minimization are presented and discussed. Some simulations of a specific PMSM drive employing the proposed algorithm are performed. The results of these simulations show that the dynamic performances are maintained, and enhancement of the efficiency up to…

Simple and Flexible Power Loss Minimizer With Low-Cost MCU Implementation for High-Efficiency Three-Phase Induction Motor Drives

2021

This paper presents a simple, practical and low-cost implementation of a power losses minimization algorithm for three-phase induction motors taking also into account both iron core losses and magnetic saturation. The algorithm evaluates, in real-time, the optimal direct axis magnetizing flux component for efficiency enhancement of the drive. A further advantage of the proposed technique is represented by a flexible and low-cost implementation by means of an ATMEL ATSAM3X8E microcontroller. The power loss minimization algorithm is tested preliminarily by means of several simulations, then, experimentally validated by applying the proposed control strategy on a 5.5 kW Field Oriented Control …

A General and Accurate Measurement Procedure for the Detection of Power Losses Variations in Permanent Magnet Synchronous Motor Drives

2020

The research of innovative solutions to improve the efficiency of electric drives is of considerable interest to challenges related to energy savings and sustainable development. In order to successfully validate the adoption of new and innovative software or hardware solutions in the field of electric drives, accurate measurement procedures for either efficiency or power losses are needed. Moreover, high accuracy and expensive measurement equipment are required to satisfy international standard prescriptions. In this scenario, this paper describes an accurate measurement procedure, which is independent of the accuracy of the adopted instrumentation, for the power losses variations involved…

A general procedure for the construction of Gorges polygons for multi-phase windings of electrical machines

2018

This paper presents a simple and effective procedure for the determination of the Gorges polygon, suitable for all possible winding configurations in electrical machines. This methodology takes into account the determination of a Winding Distribution Table (WDT), in which all the information about the distribution of the currents along the stator periphery is computed and from which the Görges polygon are easily derived. The proposed method can be applied to both symmetrical and asymmetrical multi-phase windings, including concentrated, fractional, reduced and dead-coil ones. The examples provided in this paper demonstrate the versatility of the proposed method.

Uncertainty evaluation in the measurements for the electric power quality analysis

2013

The paper deals with the uncertainty estimation in the measurements performed to assess the electric power quality. In a first steps, according to the 'ISO - Guide to Expression of the Uncertainty in Measurements' all the error sources, which give a significant contribution to the combined uncertainty associated to the measurement results, are identified. Successively, in order to analyze how the errors propagate through the measurement chain, a Monte Carlo based approach is proposed. The method exploits an ad-hoc developed simulator of the measurement process, which takes into account the particular way of propagation of all the identified error sources. Eventually, with the aim of validat…

Review of acoustic methods for space charge measurement

2015

In the last decade, due to the increased use of direct current, the space charge accumulation phenomenon has reached more interest. In this regard, several non-destructive measurement systems were used. In particular, for solid dielectrics, the acoustic methods have had greater success. This review presents a brief historical evolution of the Pulse Electro- Acoustic (PEA) method, describing the working operation, the thicknesses analyzed and the spatial resolution for the different configurations of the PEA cell. The Pressure Wave Propagation (PWP) method in both configurations Piezo-PWP and Laser Induced Pressure Pulse (LIPP) is also described.

Technical and economical evaluation on the use of reconfiguration systems in some EU countries for PV plants

2017

This paper shows the technical and economical evaluation of the application of a reconfiguration system for photovoltaic (PV) plants, considering the incentives system in some European Union countries. The reconfiguration system is an alternative to the distributed maximum power point tracking technique which used to increase the power production in the PV plants under the mismatch phenomenon. The reconfiguration techniques employ a microprocessor-based or field-programmable gate array-based system that modifies the layout of the PV plant through the change of the connections among modules. After having presented the main features working of the PV reconfiguration system allowing the improv…

A circuit model of a 5kW fuel cell

2013

In the last few years, industrial research has been focused on renewable energy sources. Owing to combined heat-power generation option, fuel cells have attracted much interest for a wide variety of research areas. Household appliances are still the most promising applications. Fuel cell modeling is still a critical topic to focus on, affecting each stage of power system design. This paper describes an empirical method to model a proton exchange membrane fuel cell. The modeling approach is applied to a 5kW Nuvera PowerFlow fuel cell. A circuit model is proposed for further applications. PSPICE implementation is described and the parameters tuning procedure is discussed. Simulation and exper…

Simulation of parasitic effects on Silicon Carbide devices for automotive electric traction

2020

Wide Band Gap (WBG) semiconductors are increasingly addressed towards Electric Vehicle (EV) applications, due to their significant advantages in terms of high-voltage and low-losses performances, suitable for high power applications. Nevertheless, the packaging in WBG devices represents a challenge for designers due to the notable impact that inductive and capacitive parasitic components can bring in high switching frequency regime in terms of noise and power losses. In this paper, a comparison between conventional Silicon (Si) and emerging Silicon-Carbide (SiC) power switching devices is presented. The effects of inductive parasitic effects and switching frequency are investigated in simul…

A Constrained Optimal Model Predictive Control for Mono Inverter Dual Parallel PMSM Drives

2018

The actual trends in the design of AC drives are directed to the reduction of the total weight, volume and cost. Usually, this implies the necessity to adopt new motor topologies and converter architectures. An important role is played by the mono-inverter dual parallel motor (MIDP), which gives the possibility to reduce the total weight and costs of power converters. This paper proposes a novel model predictive control algorithm in order to improve the transient performances of a MIDP used for an overhead carrier. The effectiveness of the proposal control is verified through some numerical simulations.

Experimental test on a fuel cell powered brushless synchronous motor for automotive applications

2014

In this paper, a fuel cell powered motor emulator is proposed. The MATLAB/Simulink model including the fuel cell stack, the motor and drive models is described. The Urban Driving Cycle test is performed in MATLAB environment. Effective operating conditions of the whole fuel cell powered motor are accurately emulated according to actual regulations in force. The emulated current profile is used for experimental tests on a 5kW Nuvera PowerFlow stack. Thanks to the proposed approach, the motor and inverter drives are accurately emulated and the provided test-bench is used to evaluate performances of the stack under test for automotive applications. Simulation and experimental results are compa…

Integration of distributed on site control actions via combined photovoltaic and solar panels system

2009

A systematic evaluation of the potential energy saving and CO2 emissions reduction on buildings was carried out, when a renewable energy system is locally installed. The exploitation of a combined solar and photovoltaic system and the integration of suitable energy management actions were deeply investigated. A model of these solar and photovoltaic components has been developed and included within a complete house simulator, capable to precisely figure out the daily electric energy consumptions of typical apartments and to measure the positive actions induced by the added renewable energy. Saving up to 40% on the energy consumptions and even more savings on wiring losses seems to be easily …

Finite-Difference Time-Domain Simulation of Towers Cascade Under Lightning Surge Conditions

2015

In this paper, the simulation of towers cascade under lightning surge conditions is presented. Finite-difference time-domain method is used to solve both the Maxwell's and telegraph equations. Maxwell's equations and the time-domain resistivity model of Darveniza are used to simulate the nonlinear behavior of the grounding system. Telegraph equations are used to describe the propagation in the overhead lines. Multiple ionizations, on different grounding electrodes belonging to various towers, can be implemented simultaneously, without making assumptions on the shape of the ionized areas.

A General Design Procedure for Symmetrical Windings of Electrical Machines

2018

Winding design methods have been a subject of research for many years of the past century. Many methods have been developed, each one characterized by some advantages and some drawbacks. Nowadays, the star of slots is the most widespread design tool for electrical machine windings. In this context, this paper presents a simple and effective procedure to determine the distribution of the EMF stars and of the winding configuration in all possible typologies of electrical machines equipped with symmetrical windings. Moreover, this procedure can also be easily implemented in a computer program in order to perform automated winding designs for rotating electrical machines. Several examples are p…

Control subsystem design for wireless power transfer

2014

Recently, the wireless power transfer has been increasingly employed. Particularly for the electric vehicles, the wireless solution is attractive for contactless battery charging, based on the Inductive Power Transfer (IPT). In this paper, a 150W prototype for IPT-based battery charging is presented and design criteria are reported. In addition to the power stage analysis, a proper control strategy is proposed. Simulation and experimental results are shown. The proposed control method aims at regulating the load current against variations in the magnetic coupling, so that the required amount of power can be supplied despite of unexpected decreases in the coupling efficiency.

Photovoltaic facade: Comparison of actual technologies

2017

This article aims to establish the economic contribution of a photovoltaic system placed on a façade of a building, replacing traditional elements such as windows and glass-cement walls with active elements. The aim is to compare the behavior of next-generation systems, which favor architectonical integration, with traditional ones. Two novel systems have been taken into account: a dye sensitized solar cell (DSSC) and blue and grey thin film silicon panels. Different generation systems have been tested and compared in terms of efficiency and fill factor.

A novel fuel cell-based power system modeling approach

2013

Nowadays, fuel cells are the most promising source of energy for stationary applications. Unfortunately, the power density of fuel cells is not adequate for modern applications. A fuel cell - based hybrid power supply is required. The fuel cell is coupled with a high-energy density power source to improve performances of the composite power source. A power management stage is introduced between the two basic sources to control the power flow path from the fuel cell to the auxiliary source and the load. In order to avoid effects of a limited power density of the fuel cell on the whole power supply, sophisticated power management algorithms are implemented. Accurate modeling is required to te…

A procedure to calculate the I–V characteristics of thin-film photovoltaic modules using an explicit rational form

2015

Abstract Accurate models of the electrical behaviour of photovoltaic modules are effective tools for system design. One or two diode equivalent circuits have been widely used even though some mathematical difficulties were found dealing with implicit equations. In this paper, a new model based on a simple rational function, which does not contain any implicit exponential form, is presented. The model was conceived in order to be used with thin-film photovoltaic modules, whose current–voltage curves are characterised by very smooth shapes. The parameters of the model are evaluated by means of the derivatives of the issued characteristics in the short circuit and open circuit points at standa…

A Cogging Torque Minimization Procedure for Interior Permanent Magnet Synchronous Motors Based on a Progressive Modification of the Rotor Lamination …

2022

This article describes a simple cogging torque minimization procedure for interior permanent magnet synchronous machines (IPMSMs), consisting of a progressive modification of the rotor lamination geometry. This procedure can be generalized for the main topologies of PMSM, independently of the number of stator slots or the location of the permanent magnets. For this purpose, a basic IPMSM structure is analyzed by means of the FEM (finite element method) approach, and then, several other IPMSM geometries, obtained by adequately modifying the rotor lamination geometry of the basic IPMSM model without changing its stator configuration, are proposed and discussed. The trends of the cogging torqu…

A suitable control technique for fault-tolerant converters in Distributed Generation

2011

The penetration of Distributed Generation (DG) in power systems is deeply changing the existing distribution networks which is becoming a very sophisticated and complex systems incorporating both active (generators) and passive systems (distribution systems, converters and loads). The necessary simplification can be obtained dealing with small networks, namely Micro-Grids, reproducing, in a smaller scale, the structure and the problems of large networks including production, transmission and distribution of the electrical energy. In order to achieve an adequate level of reliability, fault-tolerant operations of micro-grids become very important. This result can be achieved only using power …

Anomalous performance enhancement effects in Ruthenium-based Dye Sensitized Solar Cells

2017

Dye Sensitized Solar Cells (DSSCs) are nowadays more and more employed since they present lower production costs than traditional silicon photovoltaic devices. An interesting phenomenon affecting such devices consists in the fact that current density-voltage (J-V) characteristic can depend on the history of the cell prior to the measurement, which often can be assimilated to an anomalous hysteresis effect. In this work, we study such phenomenon on Ruthenium-based DSSCs through a series of measurements performed after applying different values of external electrical field to the cell. The measurements have been carried out both under simulated sunlight (AM1.5G - 1000 W/m2) and in the dark. W…

FOC with Resolver Implementation for PMSM Drives by Using a Low Cost Atmel SAM3X8E Microcontroller

2020

The aim of this paper is the low-cost experimental implementation of a field oriented control strategy for a Permanent Magnet Synchronous Motor (PMSM) by using an Atmel SAM3X8E microcontroller, mounted on an Arduino DUE board. In this electrical drive for PMSM, a resolver is used in order to measure the rotor position and speed: Therefore, the low-cost Arduino DUE performs not only FOC algorithm and phase currents data acquisition, but also a resolver-To-digital converter process, rotor position and speed data acquisition, and resolver signals management. The code has been implemented in the open source Arduino IDE, using C language, whereas the control and plot visualization interfaces hav…

Economic evaluation of PV system for EV charging stations: Comparison between matching maximum orientation and storage system employment

2016

This article addresses the problem of the choice of a generation system to be implemented to reduce the impact of charging electric vehicles at University. Based on the behaviour of the student population, it is identified the electrical load. Two possible solutions are evaluated in order to manage the peak load: an orientation of the panels in order to increase the power at defined time and the use of storage system. The main strength and weakness points of two systems are investigated by taking into account the Levelized Cost of Energy.

A Hybrid Storage Systems for All Electric Aircraft

2021

A hybrid energy storage system specifically designed for a fully electric aircraft is presented in the paper. The analysis of the time evolution of the power demand of the electric propulsion system during a test mission of Maxwell X-57, an all-electric aircraft developed by NASA, has pointed out the presence of significant peak power during take-off and air tack. Considered the issues related to weight and the volume of the energy storage systems (ESSs) in all-electric aircraft, a hybridization of aircraft ESS with a Supercapacitors (SCs) bank, devoted to smooth peak power demand, has been investigated. A comparison between the simulation results of an electrochemical battery and hybrid ES…

Maximum Torque Per Ampere control algorithm for low saliency ratio interior permanent magnet synchronous motors

2017

This paper presents an investigation on the comparison between the Maximum Torque Per Ampere (MTPA) and the Field Orientation Control (FOC) algorithms for interior permanent magnet synchronous machines (IPMSMs). In particular, this study was carried out on a small-power IPMSM with low salience ratio. Both control algorithms have been implemented in the Matlab/Simulink environment, obtaining promising results.

A Battery-free Asset Monitoring System based on RF Wireless Power Transfer

2020

In the Internet of Things (IoT) era, asset monitoring represents an appealing implementation of Wireless Sensor Networks due to the enormous benefits associated with being able to monitor and record the exact position and transportation conditions of assets, personal objects, and the like. This kind of infrastructure enables the provision of increasingly advanced services, including the ability to measure the movement speed of a monitored asset using relatively inexpensive nodes with sensing capabilities and wireless transmission and reception. These nodes would ideally employ battery-free sensors that do not require any maintenance, but conventional power supply management systems cannot s…

Design and control of a novel multi-source renewable energy system

2014

In this paper, a novel multi-input, single-inductor architecture is proposed. An innovative hysteretic control strategy of both the output voltage and the sources operating point control is designed and tested. Benefits brought by the proposed architecture over existing solutions are widely investigated. As an example, the design of a 48 V dual input system which is fed by photovoltaic and thermo-electric generators is proposed. Design guidelines are given and simulation results are presented to test the efficiency of the proposed architecture.

A multi-input, single-inductor power system for multisource energy harvesting

2013

Today, energy harvesting is drawing a great deal of attention due to modern trends in energy saving and sustainable development purposes. Among renewable energy sources fuel cells and photovoltaic arrays are the most promising for a wide variety of applications, ranging from few mWatts of wireless sensor networks to kWatts for household appliances. Coupling several harvesters and renewable sources is the winning strategy to ensure a proper supply overcoming the uncertainty and limited availability of common harvesters and renewable sources. Multisource energy harvesting is actually an open research topic involving several pressing and often conflicting requirements. System cost, complexity,…

E-bike battery charging: Methods and circuits

2013

Today, academic and industrial research is focused on innovative battery charging methods to ensure complete mobility of both handheld devices and electric vehicles. Wireless power transfer is actually the leading strategy even if efficiency related issues are to be solved for a successful marketing. In this paper, a wireless battery charging station is proposed for electric assisted pedal bikes. If compared with existing wireless solutions, the proposed system architecture improves power conversion efficiency of the charging equipment. The simulation model of the whole charging station is described in detail. The transmitter, receiver and inductive coupling circuits are described and desig…

Cogging torque comparison of Interior Permanent Magnet Synchronous Generators with different stator windings

2017

This paper presents the comparison between the cogging torques produced by four IPMSGs (Interior Permanent Magnet Synchronous Generators) with different stator winding configurations. More in detail, an IPMSG model, which is derived from a commercial geometry, is analyzed through means of a FEM (Finite Element Method) approach. Then, three more structures are determined and analyzed by adequately changing the number of stator slots of the basic IPMSG stator structure and by maintaining the same rotor configuration. From the obtained simulation results, the cogging torque components for each structure are determined and compared. From this comparison, it can be stated that the use of dissymm…

A General Mathematical Formulation for Winding Layout Arrangement of Electrical Machines

2018

Winding design methods have been a subject of research for many years of the past century. Many methods have been developed, each one characterized by some advantages and drawbacks. Nowadays, the star of slots is the most widespread design tool for electrical machine windings. In this context, this paper presents a simple and effective procedure to determine the distribution of the slot EMFs over the phases and of the winding configuration in all possible typologies of electrical machines equipped with symmetrical windings. The result of this procedure gives a Winding Distribution Table (WDT), which can be used to define coils and coil groups connections and also to simply implement winding…

Analysis and design of bi-directional DC-DC converters for ultracapacitors management in EVs

2018

The on-board energy-storage system of an electric vehicle (EV) should be able to collect large amounts of energy and to deal with fast load variations. The use of hybrid power sources as storage devices is an attractive solution, aiming at maximizing both energy and power density. The battery/ultracapacitors (UCs) combination promises to provide significant benefits. An accurate design of bi-directional converters, capable of proplery managing the charge/discharge of the UCs from/to a voltage bus, is essential. In this paper, a bi-directional DC-DC converter connected to a bank of UCs is described and the simulation results are given as well. The designed converter is a buck-boost type, abl…

A new modified Inc-Cond MPPT technique and its testing in a whole PV simulator under PSC

2015

In this paper a new modified Inc-Cond MPPT technique able to lead PV plants to work in the real MPP (Maximum Power Point) under PSC (Partial Shading Condition) is proposed. The new Inc-Cond MPPT technique working principle is fully explained, discussed and then successfully tested in a whole and reliable PV simulator conceived and set-up by the Authors in order to test and compare several new MPPT algorithms. The simulation results show that the proposed Inc-Cond MPPT technique is able to successfully lead the PV plant to work in the real MPP both in the cases of instantaneous and gradual changing of shading and of temperature conditions.

On Psychological Aspects about Electric Vehicles, Part 1

2021

The high diffusion of electric vehicles is evidenced by every sector magazine or by the catalog of all the manufacturers inserting incessantly new models. But what are the user's most hidden reactions to the new world of vehicles? Is the user ready for the fifth level of automation (fully automatic driving and absence of the driving position)? The purpose of this paper is to present and discuss the psychological aspects that influence the adoption of electric vehicles by users and beyond. Topics such as the egg and chicken paradox (electric vehicles and charging stations, who was born first) but also performance anxiety (range anxiety) will be addressed. Contradictions and irony will charac…

Preliminary test on a cascode switch for high-frequency applications

2020

Nowadays, an increasing electrification level is being addressed towards different sectors, such as transportation and industrial electronics. To bear that, high speed electrical machines represent a mature technology in different application fields, e.g. avionics, automotive, compressors and spindles. In order to guarantee high speed while keeping high power quality without adopting bulky filtering circuits, DC-AC converters shall be controlled by means of high Pulse Width Modulation (PWM) frequencies. In addition to the emerging switching device technologies, such as those based on Silicon-Carbide (SiC) and Gallium-Nitride (GaN), alternative circuital topologies are crucial in order to co…

A PV plant simulator for testing MPPT techniques

2013

This paper introduces a versatile and reliable photovoltaic systems simulator. It includes the main components of a photovoltaic plant: a PV string and a PWM controlled boost chooper. The key feature of this simulator is the ability to consider different and non-uniform irradiation and temperature conditions (partial shading and partial heating of the strings). All the different I-V and P-V or P-I characteristics can then be determined in such non-uniform irradiation and temperature conditions, with the aim to try different MPPT algorithms. The simulator also allows to verify an enhanced version of the Incremental Conductance algorithm (IncCond) where, in order to reach the real absolute ma…

A prototypal PCB board for the EMI characterization of SiC-based innovative switching devices

2020

In this paper, a preliminary PCB board for the electromagnetic interference (EMI) characterization of innovative silicon-carbide (SiC) based switching devices is presented. Packaging technological issues can determine hurdles in the high-frequency switching and high power regime where wide band gap semiconductors are intended today for Electric Vehicle (EV) applications. In particular, the parasitic inductances that emerge in such devices, must be assessed, by using e.g. EMI techniques. In this specific case, the EMI characterization is supposed to be carried out in a semi-anechoic chamber, available at the University of Palermo (UNIPA), to assess the electromagnetic disturbances according …

A Geometrical Simple Approach for Power Silicon Devices Fault Detection and Fault-Tolerant Operation of a Voltage Source Inverter

2012

Fault-tolerant converters have been widely investigated for years and nowadays an extensive technical literature on this field exists. This paper presents a novel fault detection algorithm based on a simple geometrical approach. In the algorithm analysis both the case of faults in single device and the lose of an entire inverter leg have been considered. False positive detections are avoided by considering a proper number of current samples. The proposed fault detection algorithm is characterized by simplicity, low computational and implementation effort with a consequent enough fast execution, easy control integration with the possibility to use it both in hardware in the loop systems and …

Finite-element performance comparison of IPMSMs with unsymmetrical double-layer windings

2017

This paper presents a comparison of the performances between IPMSMs (Interior Permanent Magnet Synchronous Machine) with a symmetrical and with two different types of unsymmetrical windings. The aim is to demonstrate that the adoption of slightly unsymmetrical windings does not significantly affect the performances of the machines, both in terms of cogging torque and torque/load angle characteristics, providing also the advantage of a higher possibility of choice in terms of slot number/poles ratio. More in particular, an IPMSM model (named IPMSM-1) derived from a commercial geometry equipped with a symmetrical winding is analyzed by using a Finite Element Method (FEM) approach. The simulat…

Uncertainty evaluation in the differential measurements of power losses in a power drive system

2021

Abstract In order to guarantee a correct classification in the standardized energy efficiency classes, the current standards concerning the power drive systems prescribe that their power losses must be evaluated with great accuracy. This circumstance involves the usage of expensive measurement systems, since accurate instrumentation, skilled personnel and controlled environments are required. During the design stage of a power drive system, however, the measurement of the absolute value of its power losses is not always needed. Often, in fact, it is enough to assess the power losses variations caused by a modification of either hardware or software sections of the power drive system. In the…

Reconfiguration strategies to reduce mismatch effects on PV array: An Arduino-based prototype

2014

Today, solar energy represents a widespread source of electricity among all the renewable energies. One of the major problems concerning the photovoltaic (PV) arrays is the partial shading, that is the non-uniform irradiance on its parts. The partial shading leads to several undesired effects, such as mismatch between modules and a reduction of the production of electric energy. In order to alleviate the partial shading effects, different methods can be employed. Among them, the reconfiguration of the electrical connections between modules represents an alternative solution. In this paper, an algorithm of reconfiguration for a small-scale PV plant is proposed and experimental results showin…

Implementation on NI-SOM sbRIO-9651 and Experimental Validation of Multi-Carrier PWM Techniques for Three-Phase Five Level Cascaded H-Bridge Inverter

2021

Multilevel Power Inverters (MPIs) represent a valid solution to improve the performances of energy production systems from renewable energy sources. Furthermore, the use of novel FPGA control systems allows simplifying the implementation of multicarrier PWM techniques for MPIs with computational benefits. This paper describes the implementation of several multicarrier PWM techniques on NI-SOM sbRIO-9651 for the control of a three-phase five-level cascaded H-bridge inverter. In detail, sbRIO-9651 is a control system in the field of Power Electronics and Drives (PED) programmable in the LabVIEW graphical programming environment. The paper is focused on modulation techniques implementation, te…

Experimental study on B-spline-based modulation schemes applied in multilevel inverters for electric drive applications

2019

This work presents the design, simulation, and experimental validation of new B-Spline-based modulation techniques applied to a Multilevel Power Inverter (MPI), particularly focusing the attention on the harmonic content of the output voltages of the inverter. Simulation and experimental results are proposed and discussed, mainly describing the potential benefits, such as the increase of the multi-level operation of the converter, and drawbacks (low-order harmonics) related to the adoption of B-Spline functions for multilevel inverters applied in the field of electrical drives.

Experimental Comparative Analysis of Efficiency and THD for a Three-phase Five-level Cascaded H-Bridge Inverter Controlled by Several MC-PWM Schemes

2021

Cascaded H-Bridges Multilevel Inverters are an innovative and promising solution in different application fields. This topology allows obtaining an improvement in the performance (e.g. reduced harmonic content, the low voltage stress on power components, and high efficiency) in respect to the traditional two-level inverters. In this context, the Multicarrier-PWM strategies play an important role thanks to their features. This paper presents an experimental investigation on the performance of a three-phase five-level Cascaded H-Bridge inverter by using different PWM modulation strategies. In particular, the paper is focused on the experimental validation of the main features of Multicarrier …