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

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…

An inertial system for the production of electricity and hydrogen from sea wave energy

This paper aims at describing a small scale prototype of a complete wave energy converter system for hydrogen production promoting the opportunity of installation in Sicily, in the Mediterranean Sea. The opportunity to produce hydrogen from sea-water identifies ocean wave energy as the most promising solution for electricity generation including hydrogen production and storage. Even if hydrogen is considered one of the most promising secondary sources, criticism arises from both the academic and the industrial world mainly because hydrogen production requires electricity consumption. Furthermore, safety problems concerning hydrogen storage and transport are actually the main hindrance to fu…

A Ferrite Tubular Linear Motor (FTLM): Analysis and design

The electromagnetic linear machines have wide applications in the electromagnetic aircraft launch systems [1] and in transportation systems [2]. Additional energy saving and efficiency can be achieved using a linear motor in the refrigeration application [3]. Linear electromagnetic machines are also very suitable for high-speed packaging, manufacturing sectors and precision positioning. There are different linear motor topologies. Tubular permanent-magnets are particularly attractive since they have a high thrust force density and high efficiency, no end windings, and zero net attractive force between stator and armature. There are various tubular motor topologies, in which the armature may…

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

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…

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

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

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

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…

Design of Bilateral Switched Reluctance Linear Generator to Convert Wave Energy: Case Study in Sicily

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

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 …

Minimization of detent force in a 1 kW linear permanent magnet generator for the conversion of sea waves energy: Numerical and experimental validation

Linear permanent magnet generators are widely considered for the direct conversion of energy contained in sea waves [1-3]. Both planar and tubular structures have been proposed [4-6] and all these structures present several advantages: relative high efficiency, simplicity of the structures, high sturdiness. However, as all other linear machines they present some drawbacks: oscillations in the movement, distortion in the generated electromotive force (emf), etc. In this paper we focus our attention on the parasitic oscillations of the translator which are caused by the presence of a high detent force. Detent force is generated by the fact that magnetic energy presents a minimum when the leng…

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

Electrical distribution substation remote diagnosis and control system

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 photovoltaic charging system of an electrically assisted tricycle for touristic purposes

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…

The effect of manufacturing tolerances on a tubular linear ferrite motor

This study presents a numerical and experimental study on the effect of permanent magnet tolerances on the performances of a Tubular Linear Ferrite Motor. The statistical distribution of the magnetic characteristic of a set of commercial magnets is obtained experimentally while the performances of a the tubular motor are numerically evaluated. The performances that have been considered are: cogging force, end effect force and generated thrust. It has been shown that: 1)the statistical variability of the magnets modifies the time behavior of the cogging force; 2)the value of both the end effect cogging force and the generated thrust are directly linked to the values of then remanence field o…

Overview and performance comparison of grid synchronization algorithms

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…

Geoconservation in Sicily (Italy): the Example of the Isola delle Femmine (Palermo)

Abstract The Regional Administration of Sicily recently erected Isola delle Femmine—a small island of the Tyrrhenian Sea, close to Palermo—as a geosite. A detailed geological survey has been carried out in order to define the most important geological features of the island together with the development of a new geological map based on topographic data and a digital model at 1:2.000 scale specially processed. Finally, a geological pathway through the island has been traced and illustrated. The geological substrate of Isola delle Femmine consists of a Mesozoic carbonate succession belonging to the Panormide Carbonate Platform. Two lithostratigraphic units have been differentiated. The lowest…

Local DoS applications with micro wind generation systems

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

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…

Speed control of tubular linear induction motors for industrial automated applications

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.

An electrochemical route towards the fabrication of nanostructured semiconductor solar cells

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.

An electromagnetic generator for MAGLEV transportation systems

The fundamental idea of this paper is to use the distribution theory to analyze linear generators in order to include in the mathematical model both ideal a non ideal features. This paper shows how the use of distribution theory can be used in order to establish a mathematical model able to describe both the ordinary working condition of a linear generator for MAGLEV systems as well the role of the unavoidable irregularities and non-ideal features.

Manufacturing tolerances effects on PV array energy production

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 device for PV modules I-V characteristic detection

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…

A solar assisted seasonal borehole thermal energy system for a non-residential building in the Mediterranean area

Abstract Solar heating and cooling systems are reliable and feasible solutions among renewable energy technologies. Indeed, solar thermal devices help reduce primary energy consumption and can reduce electricity demand, thus representing one of the best options for satisfying heating and/or cooling energy supply. The Borehole Thermal Energy Storage (BTES) represents one of the best promising option among the various storage technologies, because the size of the storage can be easily extended by drilling additional boreholes and simply connecting the pipes to the existing boreholes; the overall energy efficiency of this system is about 40–60%. In this paper, the authors present an applicatio…

Modelling and analysis of real-world wind turbine power curves: Assessing deviations from nominal curve by neural networks

Abstract The power curve of a wind turbine describes the generated power versus instantaneous wind speed. Assessing wind turbine performance under laboratory ideal conditions will always tend to be optimistic and rarely reflects how the turbine actually behaves in a real situation. Occasionally, some aerogenerators produce significantly different from nominal power curve, causing economic losses to the promoters of the investment. Our research aims to model actual wind turbine power curve and its variation from nominal power curve. The study was carried out in three different phases starting from wind speed and related power production data of a Senvion MM92 aero-generator with a rated powe…

A small scale prototype of a wave energy conversion system for hydrogen production

In this paper a small scale prototype of sea wave energy converter for hydrogen production and storage is presented. Laboratory prototypes of the wave energy converter device and sea water electrolyzer are presented. Experimental results are shown. A cost-effective and efficient power electronics system is designed. Experimental waveforms of the wave energy converter are imported in the power electronics simulation model to simulate the whole system as closely as possible to its effective behavior. Simulation results are shown to test the efficiency of the proposed solution.

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

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 …

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

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…

Extending the Power Range of a Solar Inverter

Solar inverters feature a minimum and maximum limit of the maximum power point voltage. Overcoming these limits leads to a disconnection of the power equipment, thus wasting the solar energy. In this paper, a solution to extend the power range of a solar inverter is presented. The proposed solution extends he minimum maximum power point limit of a commercial solar inverter by means of a battery energy storage system, including a DC/DC power converter. The battery energy storage system is connected in series to the photovoltaic module. If the photovoltaic module voltage drops below the minimum maximum power point limit, the battery energy storage system is enabled thus boosting the input vol…

Energy saving and user satisfaction for a new advanced public lighting system

Abstract The retrofit of urban lighting systems is often an advantageous means of achieving notable energy savings and improvements in the quality of light. User habits, expectations and lifestyle can contribute to the design of these systems, for example in deciding on the most appropriate control strategies or the light quality. The influence of such variables can be extended to the overall system performance. This paper presents a method of street lighting design based on two kinds of analysis carried out in a defined test area: measurements (by means of a monitoring study) and user preferences (by means of a survey). The results of this data analysis create the basis for the final desig…

Wireless battery charging for electric bicycles

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.

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

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

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…

Experimental results of a low cost weather buoy

CIGS PV Module Characteristic Curves Under Chemical Composition and Thickness Variations

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…

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

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.

Feedback linearization control of wind turbine equipped with doubly fed induction generator

This paper focuses on several control techniques of a wind turbine of rated power of about 1 MW. In particular, a wind generator equipped with an asynchronous doubly-fed induction machine has been considered and its dynamic model in MATLAB/SIMULINK environment has been implemented. Starting from this model the feedback linearization control has been derived, and several simulations have been carried out, with the aim of compare its dynamic performances with the classical field oriented control, and with the V/f control. The results allow us to conclude that a DFIG controlled by a feedback linearization technique ensures better dynamic performance.

A Ferrite Tubular Linear Permanent Magnet Generator (FTLPMG) analysis and design

Several linear synchronous generators for the exploitation of sea wave energy have been proposed. Such machines do not require reactive power for the magnetization since they use permanent magnets for the excitation. The use of permanent magnets in a rough environment such as the marine environment may be a very weak point in the application of these kind of devices. In order to overcome this difficulty, the authors in this paper propose a linear synchronous electrical generator. Its excitation uses ferrites as suitable solutions to extract energy from sea waves. This paper describes the analysis and design of an improved axially magnetized tubular permanent-magnet machine in which several …

Experimental validation of a distribution theory based analysis of the effect of manufacturing tolerances on permanent magnet synchronous machines

An experimental study on the effect of permanent magnet tolerances on the performances of a Tubular Linear Ferrite Motor is presented in this paper. The performances that have been investigated are: cogging force, end effect cogging force and generated thrust. It is demonstrated that: 1) the statistical variability of the magnets introduces harmonics in the spectrum of the cogging force; 2) the value of the end effect cogging force is directly linked to the values of then remanence field of the external magnets placed on the slider; 3) the generated thrust and its statistical distribution depend on the remanence field of the magnets placed on the translator.

Reconfiguration Techniques of Partial Shaded PV Systems for the Maximization of Electrical Energy Production

In this paper, the research of the optimal layout of photovoltaic (PV) modules in a PV array giving the maximum output power under different shaded working conditions is carried out. The particular condition of non uniform solar exposition of the modules is analyzed. The study of the different configurations has been carried out starting from a circuital model used for the design of PV cells and for the simulation of the working behavior of PV arrays. The attained results appear to be interesting although the complexity of the problem in mathematical terms is huge when the number of panels is high. Moreover, the results confirm that this approach often allows to attain a higher electrical e…

A DC-DC power converter for PV module characterization

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.

The role of the effect of manufacturing tolerances on a tubular linear ferrite motor

Electric machines are often designed without considering workmanship and materials tolerances. Their manufacturing process involves a series of steps, starting with raw materials and ending with the machine assembly. In each of these steps occur deviations due, for instance, to mistakes in positioning tools or to the tolerances in the electrical and magnetic characteristics of the materials. These deviations may cause unwanted parasitic effects such as torque ripple, losses or acoustic noise. Such effects have to be considered especially in machines used in industrial drives for high performance applications. Moreover the tolerances in the magnetic materials have a considerable effect on th…

Parametrical study of multilayer structures for CIGS solar cells

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

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…

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

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.

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

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.

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

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.

Economic analysis on the use of wired and wireless recharging systems

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…

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

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.

Impatto delle nuove tariffe elettriche sulla diffusione del fotovoltaico in Italia

L'articolo illustra i principali contenuti della recente riforma delle tariffe elettriche e valuta le conseguenze, in termini di convenienza economica, della riforma sulla diffusione dei piccoli impianti fotovoltaici a uso domestico.

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

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 general comparison between various types of linear generators for wave energy conversion

This paper presents a general comparison between various types of linear generators for wave energy conversion. According to the type of magnetic configuration they are distinguished as: linear asynchronous generators, linear generators with permanent magnets and linear reluctance generators. The paper shows their peculiarities and discusses their field of applications.

A photovoltaic system suitable for the battery pack charging of an electrically power assisted velocipede

The paper describes the designing, sizing, realization and setting up of a complete system suitable for the management of an electrically power assisted velocipede using a photovoltaic module for the charging of the batteries. In the work an overview on the sustainable mobility needs and on the commercial electrically power assisted velocipedes is presented and the "Ecolapa" prototype, set up in the SDELab laboratory of Palermo University, is precisely described underlining the designing, implementation and setting up phases of the photovoltaic charging system settled up on the velocipede. Moreover tests oriented on the setting up of the whole system and validation tests on the prototype ar…

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

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…

A security and surveillance application of the innovative Monitoring Underwater Buoy Systems (MUnBuS) on the Protected Marine Area (AMP) of capo gallo (PA-IT)

The proposed low cost systems shows the results obtained in the implementation and testing on real security application to Protected Marine Area surface and submarine environment of a innovative Monitoring Underwater Buoy Systems (MUnBuS) for installation with IR-CCTV-Cam, ultrasonic dolphin warning system and Green Laser Perimeter Detection. This concerning innovative Monitoring Underwater Buoy Systems that can be remotely controlled from the ground, air, satellite and sea and from a Center of Supervision Telecontroller And Data Acquisition and Monitoring (Mobile- STADAM Center). The Buoy is hosts for the radio or satellite communication equipment, the downloading and telemetering data equ…

Electromechanical Numerical Analysis of an Air-Core Pulsed Alternator via Equivalent Network Formulation

In this paper, the numerical analysis on an air-core pulsed alternator is presented. Since compulsators are characterized by very fast electromechanical transients, their accurate analysis requires strong coupling between the equations governing the electrical and the mechanical behaviors. The device is investigated by using a dedicated numerical code capable to take into account eddy currents, compensating windings, as well as the excitation/control circuits. Furthermore, the code is capable of modeling centrifugal forces and vibrations acting on the shaft due to electric and mechanical unbalances or to misalignments of the shaft from its centered position. This makes the code a very power…

Critical issues and future prospects of the secondary substation in smart grid context

This paper is focused on the new role of the secondary substation in the smart grids context. This innovative view has been proposed and developed in the framework of two Research Projects: NewCabELARC Project and Reipersei Project. The latter provides a concrete and comprehensive low cost solutions for the smart grid monitoring and control, allowing the real diffusion and integration of Distributed Generation and the full exploitation of Renewable Energy Sources. In this field, this paper shows how the secondary substation (SS) takes the role of smart transducer node where innovative devices can be located, collecting the measurement data coming from the field devices (power and energy met…

Realization of an Energetic Hub Based on a High-Performance Dish Stirling Plant

In this work the realization of an energetic hub based on a high-performances dish Stirling system, at the DEIM of the University of Palermo, is presented. The realized system is the first top rated solar thermodynamic plant directly connected to the national electric grid. The connection permits the electricity injection into the grid and allows to access to national renewable energy incentives regime. The system realization was possible thanks to an international cooperation between the University of Palermo and the private company Horizon S.r.l., official partner of Ripasso Energy AB, owner of this technology. Initial data of the plant energy production and the foreseen improvements for …

Design, modeling, and simulation of a photovoltaic water pumping system

Electric pumps cannot be fed in those areas where they are not connected to the electric public distribution grid. In those areas, it is useful to feed electric pumps by means of the electricity generated from renewable energy sources plants. Among these, the Solar Water Pumping Systems feed electric pump thanks to the electricity generated by a photovoltaic plant. In this paper, a whole SWPS is fully designed, modelled, and simulated in Matlab environment. The proposed implementation is an useful tool for SWPS testing.

A PV plant simulator for testing MPPT techniques

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…

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

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…

Energy and Network Models for the Intelligent Control of Distributed Systems

This paper presents detailed energy and network models for the intelligent control of a distributed system which also comprises power generation from renewables. The two models provide interactive energy monitoring, intelligent control and power demand balancing at home, block and neighbor level. Particularly, it is here described how the energy model works and also details of how it has been validated are here given. Moreover, it is shown how the energy model simulation results are transferred to the network simulation software SynerGEE, set up by GL Noble Denton Industrial Services Ltd (UK), in order to fully perform network simulations.

Photovoltaic plant array reconfiguration: Design of a new device

An efficient strategy to improve unequally irradiated PV plants performances is based on the reconfiguration of the connections between the modules. In this paper, an algorithm, for this purpose conceived, is presented. Moreover, the design, realization and finally also the set up of a new reconfiguration system device is fully shown and discussed. The algorithm conceived simulates several possible series-parallel connections under varying irradiation conditions, and determines the optimal modules connection in order to get the maximum output power. In this way, the reconfiguration system may set up the reconfiguration strategy. The reconfiguration system prototype set up, basically consist…

Energy and Economic Comparison of Different Conditioning System among Traditional and Eco-Sustainable Building

The use of bioclimatic principles can reduce energy demands and CO2 emissions in the building sector [1-. Costs are one of the most important barriers to a widespread adoption of the green architecture technologies [4-. The aim of this study is to compare the energy and economic performances of two buildings: a real residential bioclimatic building located in Cinisi (a small town near Palermo, Sicily) and an imaginary residential building supposed having the same geographical location, cubature, shape and orientation as the bioclimatic building but built by conventional building materials. The tools used for this study were TRNSYS and HOMER

Active power maximizing for Wind Electrical Energy Generating Systems moved by a Modular Multiple Blade Fixed Pitch Wind Turbine

This paper proposes a new solution for wind electrical energy generating system (WEEGS). The system here taken into account is moved by a modular multiple blade fixed pitch wind turbine (MMBFPWT) and foresees a new MPPT algorithm whose main characteristics are low cost, low noise, buildings simplicity and modularity. The mathematical model of the entire WEEGS has been here developed taking into account all the components starting from the wind turbine and ending with the electrical grid. The WEEGS mathematical model has been implemented in Matlab-Simulink in order to carry out the simulations needed to test the effectiveness of the proposed WEEGS. The simulations results show the effectiven…

Design, sizing and set up of a specific low cost electronic load for PV modules characterization

In this paper, the design, sizing and set-up of a specific low cost electronic load, based on a DC-DC step-down converter, suitable for the PV module I - V characteristic curves determination, is described. In particular, for its set up, a low cost and user friendly micro-controller has been employed in order to generate the PWM signal. The measures carried out connecting the electronic load prototype to a commercial PV module are here presented and discussed. The conceived electronic load has allowed the determination of 80% of the PV module characteristic curves in 2 s. This low measurement time, lower than the time intervals in which weather conditions may change, allows to assume as con…

Leading the way toward fuel parity in photovoltaics: The utility-scale market in Sicily, Italy

The global photovoltaic (PV) market has been growing exponentially since almost twenty years. This huge demand for photovoltaic systems has been mainly driven by public subsidies in the form of a variet y of national incentive schemes. However, in Countries where successful incentive schemes have been pioneered and are now – as planned - being brought to an end, the PV market is called to the challenge of surviving without any incentive to the end user. Grid and fuel-parity represent the keystone of this emerging new phase in the history of this renewable energy technology. In this paper we present a sensitivity analysis showing that in Sicily, Italy, the Levelized Cost of Energy from utili…

Analysis of interconnection substations for sewave power farms

In this paper we analyse the interconnection of a seawave power farm to the grid. The generator type used in the farm is a linear synchronous generator driven from the seawaves that generates, highly distorted emfs. We presents 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 a.c.-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 directly connected to the main.

Speed Control of a two-Degrees of Freedom Induction Motor with Rotor Helical Motion for Industrial Applications

This paper describes the realization of a two-degrees of freedom induction motor prototype with rotor helical motion, suitable for several industrial applications as grinders, augers, drilling and milling spindles, robotic arms and drives for medical tools and prostheses. This prototype was realized by combining a three-phase tubular linear induction motor (TLIM) with the stator of a three-phase rotary induction motor, resulting in a THMIM (Tubular Helical Motion Induction Motor). Moreover, a possible simple electrical drive, capable to control the helical motion, is proposed, simulated and analyzed. In particular, the mathematical model of the THMIM has been initially developed and, then, …

Critical assessment of support for the evolution of photovoltaics and feed-in tariff(s) in Italy

Abstract The feed-in tariff(s) mechanism involves an obligation on the part of an electricity provider to purchase electricity generated by renewable energy sources in its relevant area, paying a tariff determined by public authorities and guaranteed for a specific time period. Feed-in tariff(s) have been the primary mechanism used for supporting the development of renewable energy sources in the EU and, up to date, they are being applied in 20 EU Member Countries. On 6 July 2013, the Italian experience with feed-in tariff(s) for photovoltaic systems finished. During its lifetime of eight years, this incentive mechanism, named “Conto Energia”, was characterized by periods of great success f…

Experimental test of the performances of a photovoltaic modules model

In this paper, a measurement-based modeling technique for PV panels oriented to power electronics design is proposed. The proposed modelling approach aims at an accurate modeling of the whole PV curve and not only around a few remarkable points. The proposed approach is based on an experimental characterization of the module under test. In fact, the incompleteness of manufacturers' data and the knowledge of physical parameters are the main source of inaccuracy in existing modelling approaches. The proposed approach is applied to a four lumped parameters model of a Conergy E215P solar module. Tests are performed under natural light. The parameter identification procedure is described in deta…

Incidence of PV module rated power tolerances on PV system energy production

Discussing the electrical energy production of a PV system realized by PV modules with a large range of tolerance for the rated power values is the aim of this paper. In particular, the paper shows how the incidence of tolerance can be significant, in terms of output power reduction, when the PV system works in partial shading condition. For this issue, using a tool developed for this purpose, several simulations have been run, which consider different tolerance values for the module rated power and different shading patterns for the PV array. The authors quantify the peak power values of the different system configurations, showing the importance of the choice of modules with reduced toler…

An embedded diagnostic system for wheelchairs brushless drives monitoring

The implementation of a microcontroller based monitoring system for the diagnosis of a brushless synchronous motor drives is presented. It finds its primarily interest on motorized wheelchair for disabled people. The embedded system mainly controls all the principal parameters of the electrical drives together with the power supply system. Pre-failure and failure conditions are routinely logged and, depending on the malfunction severity, alarm messages are created and sent to a remote base station by using the GSM wireless network.

Deep learning strategies for automatic fault diagnosis in photovoltaic systems by thermographic images

Abstract Losses of electricity production in photovoltaic systems are mainly caused by the presence of faults that affect the efficiency of the systems. The identification of any overheating in a photovoltaic module, through the thermographic non-destructive test, may be essential to maintain the correct functioning of the photovoltaic system quickly and cost-effectively, without interrupting its normal operation. This work proposes a system for the automatic classification of thermographic images using a convolutional neural network, developed via open-source libraries. To reduce image noise, various pre-processing strategies were evaluated, including normalization and homogenization of pi…

Economic analysis on dynamic photovoltaic systems in new Italian “feed in tariffs” context

Dynamic photovoltaic generators, based on the application of solar-trackers, are able to give an increment to the electric energy production from solar source. Their realization and maintenance costs are certainly higher than those of fixed ones. In this paper the Authors propose a method to estimate the increment of electrical energy generation that must be guaranteed by a dynamic photovoltaic generator, so as its realization could be more favorable with respect to that of a fixed generator one with the same rated power. This method, developed by means of classical economic indexes like the Pay-Back-Period and the Net Present Value, takes in to account the economic incentives for the PV sy…

Test cycles for the characterization of electrical drives devoted to wheelchair applications

Today electrical wheelchairs are giving valuable increase of the quality of life of disabled people in developed countries. Despite the increasing diffusion of such an aid tool, specific standards for the characterization of their electric drives are not so developed as those available for urban electric vehicles. This paper presents a proposal for the test characterization of a wheelchair drive by means of test cycles with fixed speed trajectories. To this aim, the method, which is well known in the field of automobiles, has been purposely adapted and the obtained simulation results are satisfactory.

Identification of the inertial model for innovative semi-immergible USV (SI-USV) drone for marine and lakes operations

The proposed project shows the results obtained in the implementation and testing in lacustrine and marine environment of a nautical remote controlled vehicle with surface navigation and innovative features Semi-Immergible (SI-USV). This vehicle is based on a pending patent belonging to Palermo University (Patent Pending RM2012A000209 and Patent RM2014Z000060) concerning innovative semi-immersible vehicles (SI-Drone), that can be remotely controlled from the ground, air, satellite and sea also during the semi-immersible operation. Given its low draft, the electric powered vehicle, coupled with jet propulsion, makes it possible to navigate in shallow waters, coastal shipping or sandbars.

Effects of the air density value on a wind generator electricity production capability

The paper main issue is the evaluation of the influence of the air density value on the electricity production capability of a wind generator. Two different density air mathematical models, where the density has not a constant value, are here taken into account and compared in terms of reliability, accuracy and computational burden. Evaluations are carried out thanks to a horizontal axis wind generator full model built by the Authors in Matlab/Simulink environment. Simulation results are compared with real data.