Green Data Centres providing ancillary services to power grid

2015

This work investigates the possibility for a Data Centre to provide services to the Grid. In particular, the paper simulates a sudden shift of frequency because of a power decrease and estimates how a real-life Data Centre can contribute the secondary frequency regulation.

Energy Management of a Hybrid Photovoltaic-Wind System with Battery Storage: A Case Report

2019

This work presents a case report related to the management and the monitoring of a hybrid photovoltaic-wind system with battery energy storage, installed at the administrative offices building of the municipality of Valderice (Italy) within the framework of the Italy-Tunisia ENPI cooperation project Le Développement Durable Dans la Production Energétique Dans le Territoire (DE.DU.ENER.T.). The paper describes the hybrid system and briefly reports the monitoring data for a whole year, comparing the real production with the expected one and evaluating some performance indexes of the system. The performance indexes are very simple and have been defined only with the purpose of sh…

WITHDRAWN: Perspective on hydrogen energy carrier and its automotive applications

2013

On multi-objective optimal reconfiguration of MV networks in presence of different grounding

2015

The present work faces the traditional multi-objective optimal reconfiguration problem of a distribution grid including the safety issue in the objective functions. Actually, in many medium voltage networks still transformers with ungrounded neutral and with resonant grounded neutral coexist in the same area. This may be sometimes cause of problems during a single-line-to-ground fault if the ground electrodes of one or more cabins, initially designed for satisfying the safety conditions in a resonant grounded neutral network, after the reconfiguration are in a grounded neutral one or vice versa. In the paper a safety objective function is defined and the Non dominated Sorting Genetic Algori…

Effects of double ground faults in Wind Farms collector cables

2015

Medium Voltage collector cables of Wind Farms have metal shields connected to the grounding systems of the towers and of the connection station. Thanks to this bonding, when a ground fault occurs, the fault current splits itself among all the grounding systems of the wind farm, this causing a reduction of the ground potential rise at the fault location. Nevertheless, in presence of double ground faults, very high ground potential rises occur at the two fault locations and safety against electric shock is not always assured. In order to study this issue, the paper presents a model for simulating in a simple way the effects of double ground faults occurring in Medium Voltage collectors of ext…

Mathematical Model of a PM Brushless Motor with Different Stator-Rotor Pole Pairs Number

2013

The paper presents a mathematical model of Permanent Magnet AC brushless machines (PMSM) having a number of stator poles-obtained via the distribution of the three-phase winding- different from the rotor one, realized by the displacement of the permanent magnets. For these so- called ‘Fractional-Slot’ motors (where few total slots generate high equivalent number of poles) the available mathematical models appear partial and/or incomplete, despite of numerous designing considerations made in literature. In this paper an analytical approach is developed to point out an instantaneous- values mathematical model with concentrated parameters, that can be suitable for control architecture systems …

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…

The evolution of the FIT mechanism in Italy for PV systems: a critical analysis

2013

The paper presents an analysis of the Feed'in Tariffs (FIT) mechanism development in Italy from 2005 to 2013 and named “Conto Energia”. In particular the work examines the five editions of the “Conto Energia”, highlighting both advantages and critical issues for the PV market development in Italy; this analysis is particular interesting due to the fact that the cap on FITs in Italy has been reached in June 2013.

Green Data Centres integration in smart grids: New frontiers for ancillary service provision

2017

Abstract The paper presents a study, conceived within the GEYSER FP7 co-funded European research project, on the ancillary services that Green Data Centres (GDCs) can provide, focusing, in particular, on spinning reserve. More in detail, the main contribution of the paper is to show how GDCs can be involved in the secondary frequency regulation process of a smart distribution grid, for contrasting the disturbing effects of unexpected variation of the energy production. With this aim, a real data centre, owned by Engineering S.p.A., is simulated as connected to the Medium Voltage IEEE 14-bus test grid where some RES-based generators are supposed to exist. Simulations are carried out in order…

A New Platform for Automatic Bottom-Up Electric Load Aggregation

2017

In this paper, a new virtual framework for load aggregation in the context of the liberalized energy market is proposed. Since aggregation is managed automatically through a dedicated platform, the purchase of energy can be carried out without intermediation as it happens in peer-to-peer energy transaction models. Differently from what was done before, in this new framework, individual customers can join a load aggregation program through the proposed aggregation platform. Through the platform, their features are evaluated and they are clustered according to their reliability and to the width of range of regulation allowed. The simulations show the deployment of an effective clustering and …

Adoption of bonded magnets in place of sintered NdFeB: Performance and economic considerations on a small power generator

2015

Bonded magnets are giving promising results when adopted to replace expensive rare earth magnets. The possibility to “modulate” the magnetic characteristics by varying the binder percentage allows the opening of new lines of investigation and to face the problem of rare earths cost. In the paper a small power generator prototype has been equipped with bonded magnets realized in the Authors' Laboratories; it has been tested and compared with the original generator mounting NdFeB sintered magnets. FEM simulations are validated by means of experimental tests. Economic comparisons are proposed.

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 method for the evaluation of fault current distribution in complex high voltage networks

2015

Abstract The paper presents a method for the study of large interconnected earthing systems in High Voltage networks. The mathematical model proposed for calculating the distribution of the Single-line-to-Earth fault current is useful for a methodical and accurate analysis of complex systems having meshed configuration and more sources, and has practical application for the Transmission System Operator. Two case studies are provided. The first one considers a fault occurring inside and outside a station in a real 220 kV transmission network. In the second example, the proposed methodology is compared with the classical “Double-sided elimination” method.

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.

Uncertainty management in the measurements for the electric power quality analysis

2014

The paper deals with the uncertainty estimation in the measurements performed to assess the electric power quality. In a first steps, 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 combine and propagate through the measurement chain, four approaches are proposed and validated. These approaches entail a greater and greater uncertainty overestimation, but, at the same time, require less and less time and resources. Therefore, the four methodologies are perfectly adequate for the implementation of the PUMA (Procedure for Uncertainty Management) metho…

Thin Film CIGS Solar Cells, Photovoltaic Modules, and the Problems of Modeling

2013

Starting from the results regarding a nonvacuum technique to fabricate CIGS thin films for solar cells by means of single-step electrodeposition, we focus on the methodological problems of modeling at cell structure and photovoltaic module levels. As a matter of fact, electrodeposition is known as a practical alternative to costly vacuum-based technologies for semiconductor processing in the photovoltaic device sector, but it can lead to quite different structural and electrical properties. For this reason, a greater effort is required to ensure that the perspectives of the electrical engineer and the material scientist are given an opportunity for a closer comparison and a common language.…

Design optimization for the adoption of bonded magnets in PM BLDC motors

2014

The increment of the manageable power in machines where the normally adopted ferrites are replaced with bonded magnets can vary and can introduce saturation problems depending on the variations in the magnetic circuit design. The saturation of the magnetic circuit distorts the phase voltages, introducing undesired harmonics in the connection to the mains. Combined modifications of both stator poles and rotor ring of a Brushless DC motor are proposed to evaluate their impact on the increment of the manageable power and on the harmonic content. Several magnetic circuit modifications have been considered and the paper presents the results of the most reasonable solutions, obtaining significant…

Mixed heuristic-non linear optimization of energy management for hydrogen storage-based multi carrier hubs

2014

In this paper, an heuristic and non-linear programming based algorithm to optimally operate an energy hub plant is proposed. The energy hub plant described in this work is the test system for the European INGRID research project. The Energy Management System defines the optimal energy flows dispatch in order to obtain the energy balance and the maximum profit for the owner of the plant. The problem is highly constrained and non-linear, for this reason the methodology cannot rely on Linear Programming (LP) methods. The Energy Management System manages two energy carriers, electricity and hydrogen, interfacing three distribution networks: the electricity, the hydrogen and the methane networks…

Photovoltaic module characteristics from CIGS solar cell modelling

2013

We describe our approach to the task of modelling, both at single cell structure and complete module levels, during the solar cell technology development process. This can give very helpful indications, in terms of global photovoltaic module characteristics, for the assessment of intermediate research results and planning of further experiments. We make reference specifically to the fabrication of thin film CIGS solar cells by means of single-step electrodeposition, a technique which appears fairly easy and low-cost but, at the same time, can lead to quite different structural and electrical properties.

Distribution grid analysys through PSAT open source tools

2015

In this paper a study of an electrical distribution grid with presence of renewable energy sources performed using the Power System Analysis Tool is presented. The paper describes the load flow analysis of a real existing grid owned by the Italian DSO “ENEL Distribuzione SpA” and located in an urban area.

A novel heuristics-based energy management system for a multi-carrier hub enriched with solid hydrogen storage

2014

In this paper, an efficient optimization algorithm for the energy management of a grid-connected energy hub plant is proposed. The Simulated Annealing algorithm is adopted for the solution of the energy management problem aiming at the profit maximization for the owner of the energy hub plant. The use of a heuristic algorithm was required by the non-linearity of the efficiencies of each component in the energy transformation stages. The proposed heuristics is applied to a large energy hub, corresponding to the simulation of the test-bed that is being designed and developed inside the ongoing INGRID European research project.

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

2007

Impact of Novel Energy Management Actions on Household Appliances for Money Savings and CO2 Emissions Reduction

2009

In order to obtain CO2 emissions reductions, energy management control actions inside apartments and detached houses have to be carried out. In this work, new control actions devoted to the reduction of electrical energy consumptions inside typical Italian apartments are proposed. These “Distributed on Site” (DoS) actions consist in employing specific control strategies to smartly exploit the hot water provided by a solar panel, the electricity generated by a photovoltaic panel and the delayed starting of appliances.

Il Laboratorio per lo Sviluppo Sostenibile e il Risparmio Energetico (SDESLab) nell’ambito industriale siciliano

2009

L’articolo presenta le attività del Laboratorio per lo Sviluppo Sostenibile ed il Risparmio Energetico (SDESLAB) dell’Università degli Studi di Palermo nei confronti dell’ambito industriale, con particolare riguardo a quello siciliano. Vengono illustrati gli ambiti di intervento del Laboratorio: ricerca scientifica di base, consulenza alle industrie e alle imprese, formazione, informazione e divulgazione nei vari campi dello sviluppo sostenibile con particolare riguardo a energie rinnov- abili, azionamenti elettrici, automazione industriale e gestione automatizzata dell’energia. Vengono descritte le attrezzature di cui il Laboratorio si avvale per le proprie attività, i progetti di ricerca i…

Vehicles PEMFC Power System Mathematical Model for Integrated Design

2013

Reducing energy consumptions and CO2 emissions in European countries: a review on legal environment and increasing use of photovoltaic energy for Ele…

2010

In Europe, the building sector is ranked second in terms of CO2 emissions, just after transport. Particularly, it accounts for 25% of the overall CO2 emissions. Moreover, in order to reduce CO2 emissions, European legislations encourage the use of renewable energies and, among them, particularly the use of PhotoVoltaic (PV) one. This because the connection between the use of PV clean energy and the reduction of CO2 emission is well demonstrated. In this context, the first part of the paper is focused on the regulations related to building energy efficiency while the second part investigates the deployment of PV source all over Europe.

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…

A new control system prototype for the energy production maximization of a unequally irradiated PV system

2011

This paper deals with the mismatch effect due to a unequally irradiation on a PV (PhotoVoltaic) system. The mismatch effect due to the partial shading of a PV module can be limited thanks to the installation of both bypass and block diodes. Unfortunately, this solution cannot fully solve the disvantages related to the mismatch effect. The Authors, in previous papers [1, 2], have theoretically demonstrated that the mismatch effect can be solved by changing the parallel/series connections of the modules of a PV system, taking into account each module radiating condition. This paper represents a first step of the experimental development of the above mentioned theoretical result. Specifically,…

Le macchine elettriche per la generazione di energia da fonte eolica

2006

CARATTERIZZAZIONE ELETTROMAGNETICA DI IGBT IN PRESENZA DI SCARICHE PARZIALI

2014

High Performance Field Oriented Rotor Control of Induction Generators

2006

A SURVEY ON SMART GRIDS ACTIONS AND COMPONENTS FOR ENERGY CONSUMPTIONS OPTIMIZATION

2014

In the paper a survey on the features that a smart grid has to perform for energy consumptions optimization are presented and explained. By optimizing the loads usage with the grid priorities both end-users and the energy providers can save energy (and so CO2 emissions) and money. In the paper the conceive of an architecture in-home and at residential level is proposed to arrange a smart grid with its intelligent and connected load consumers. Qualitative results from the European research project “BeyWatch” are here mentioned in order to explain how the conceived main services in smart grid, like monitoring and control services, energy management services and load management services allow …

Una Via Elettrochimica per la Fabbricazione di Celle Solari a Semiconduttori Nanostrutturati

2009

Nella memoria si presentano i risultati preliminari su un processo di crescita elettrochimica di materiali nanostrutturati mediante l’impiego di stampi nanoporosi. Vengono quindi analizzate le possibili applicazioni del processo alla fabbricazione di semiconduttori nanostrutturati di interesse nel settore fotovoltaico, quali il CIGS, e le implicazioni dal punto di vista delle tecniche di caratterizzazione e di modellazione per dispositivi basati su tale tecnologia.

The BEYWATCH FP 7th European Scientific Project: dissemination and standardization activities, liaison with other projects

2012

The outcome of the BEYWATCH project has been spread in various ways, including different publication channels such as scientific journals and conferences, exhibitions, standardisation efforts and liaison with other relevant scientific projects. An overview of the dissemination activities is given in section 2, they include details about the Internet presence and the project presentations in workshops and conferences. Besides, some effort has been put into contribution to standardization. Contributions to standardization is found in section 3. Further, the project has set up liaisons to other European research projects. For each such activity, topics and forms of cooperation are described in…

The FP7 BeyWatch European scientific project: general features and design criteria of the Combined Photovoltaic Solar (CPS) system within the BEYWATC…

2011

This paper includes the general features and design criteria of a combined photovoltaic solar system (CPS) and its allocation within the entire architecture of the BeyWatch system. The CPS main functionalities and characteristics, the description of the CPS main components and the CPS electronic control and monitoring subsystem, together with the description of the Firmware design and communication protocols are here reported. The Combined Photovoltaic and Solar system (CPS) is a Renewable Energy system that produces thermal and electrical energy and the design has been based on a modular approach.

Reduction of Electrical Energy Consumptions through New Energy Management Actions on Connected Household Appliances

2008

Un Sistema di Generazione di Energia Elettrica da Fonte Eolica Mosso da una Nuova Turbina Eolica Modulare del Tipo a Passo Fisso

2008

Diagnosi wireless su apparecchiature elettriche affette da scariche parziali di origine interna

2013

Tra le tecniche di rilevazione per apparecchiature elettriche affette da scariche parziali, un metodo innovativo è costituito dalla rilevazione di tipo wireless che produce vantaggi e benefici per gli utenti, i produttori di apparecchiature e le imprese distributrici dell’energia elettrica.

SPEEDAM 2010 Poster REC0616: An electrochemical route towards the fabrication of nanostructured semiconductor solar cells

2010

Benefit at Grid Level by Using DoS Actions via Combined Photovoltaic and Solar Panel System

2010

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…