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The interest towards bifacial PV technology has increased over the last years, due to its potential capability of obtaining higher efficiencies with respect to traditional monofacial cells. Thus, the aim of this work is to present an experimental investigation on an innovative photovoltaic technology, such as the bifacial solar cells based on monocrystalline substrate. This analysis is mainly based on the determination of the current density/voltage, power density/voltage, External Quantum Efficiency (EQE) and Laser Beam Induced Current (LBIC) characterization. Interesting results are presented and discussed, demonstrating that the bifacial silicon solar cells can be a very promising technology with high electrical performances and efficiency.

In a previous paper, we proposed a control strategy for interior permanent synchronous motors, which takes into account also the reduction of the motor power losses. The novelty of the suggested approach is that it takes into consideration the variations of all the motor parameters that have an influence on its efficiency. In order to verifyon the field the effectiveness of this new method, we implemented the proposed loss model algorithm in a control drive system and compared its performances, in terms of energy losses with respect to other conventional techniques.

The FPGA represents a valid solution for the design and implementation of control systems for inverters adopted in many fields of power electronics because of its high flexibility of use. This paper presents an overview and an experimental validation of the MC SPWM techniques for a three-phase, five-level, cascaded H-Bridge inverter with FPGA controller-based. Several control algorithms are here implemented by means of the VHDL programming language and the output voltage waveforms obtained from the main PWM techniques are compared in terms of THD%. Simulation and experimental results are analyzed, compared and discussed.

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 to the levels of compliance indicated by the standards. The proposed prototype can work properly at the following levels of voltage, frequency and load power: 28.5 V, 2 MHz and 40 W. Details concerning the layout design and the prototype manufacturing are discussed.

L’attività di ricerca è orientata all’analisi del comportamento in transitorio, durante una eventuale condizione di fulminazione atmosferica diretta e/o indiretta, di impianti di terra interconnessi in sistemi elettrici in media tensione (MT). Usualmente l’interconnessione è realizzata attraverso la guaina metallica dei cavi in MT o mediante l’impiego di corde di rame nudo interrate parallelamente al percorso dei cavi stessi. Tale interconnessione, impiegata durante il normale servizio elettrico per limitare l’ampiezza dell’eventuale corrente di guasto a terra, contribuisce anche a modificare la distribuzione della corrente di fulmine in caso di fulminazione diretta o indiretta dell’impianto e, di conseguenza, le eventuali tensioni pericolose trasferite. L’approccio seguito è quello di campo (full wave) già impiegato con successo per l’analisi di un sistema di protezione dalle scariche atmosferiche (LPS) [1]. E’ basato sulla risoluzione numerica di una versione modificata dell'equazione integrale del campo elettrico (EFIE) nel caso thin-wire (1), nel dominio della frequenza, impiegando l’analisi di Fourier discreta (DFFT).

In this article is presented the preliminary evaluation of the performance of radiation transmission of glass block, used in support of photovoltaic cells, investigating different internal surface points of the block, which are subject to different shading during daylight hours. The aim is to establish how the edging setting, the only opaque element, can reduce the amount of light radiation during the day, introducing in this way a reduction of efficiency of the entire generation system. The generation system can be based on traditional photovoltaic cells or on the most suitable dye sensitized solar cells. An experimental measurement setup employing a microprocessor-based instrument has been created and a set of measures have been carried out. The measures prove that the shading effect at different irradiation angles do not affect significantly the lighting over the PV cell.

The aim of this work is to estimate e-mobility trends, which are crucial for understanding the market and the infrastructure expansion over the next years and debate which are the persuasive policies to improve the diffusion. At the present time between the numerous and diverse standards and rules there are two charging types for electric vehicles: high power DC and AC charging modes. It will be stimulating to understand which technology will overcome in the following few years and if the charging mode option on a given electric vehicle (EV) affects its sales results. This paper addresses the existing e-mobility scenario in Norway and Italy, in particular evaluating: EV technical and commercial features, EV market connected to national incentive strategies, technical and diffusion connector type and charging mode. In conclusion, based on the existing history and analysis of the informations accessible, this work presents a measured outlook on the probable progress of this expanding niche market.

The paper provides the results of a detailed experimental study on the variations of the characteristics of an interior permanent magnet synchronous motor, when load, speed and/or magnetization conditions vary. In particular, the characterization is carried out by assessing, for several working conditions, the motor parameters that influence its efficiency. From the knowledge of the variability of these parameters, it is possible to develop a dynamic model of the motor, which accurately describes its behaviour and allows estimating the power losses for whatever speed and load. In order to validate the model, the values of the power losses obtained by using the model are compared with the values measured with experimental tests. The study shows that it is possible to maximize the motor efficiency just acting on the direct axis current component, and therefore, it can be considered a first step towards the definition of a loss model algorithm for a control drive system able to minimize in real-time the power losses of the motor