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This paper proposes a methodology to evaluate the maximum power, which can be drawn out from a PV plant on the basis of its geographic location and local weather conditions. These evaluations are carried out through data analytics, starting from an experimental knowledge base, which is built through aggregation of data coming from electric characterization tests, temperature measurements and weather stations. The first part of this methodology is focused on the characterization of irradiance sensors, highlighting the dependency of its measurements on sun elevation angle. The evaluations are then focused on a real application, which consists in a Hetero Junction Intrinsic Thin Layer (HIT) PV panel equipped with temperature sensors. The estimations are obtained by using weather data coming from measurement stations located near the PV panel. The comparison with experimental results highlights the performance of the proposed power prediction method, especially during summer periods.

This paper describes a preliminary analysis on the integration of renewable energy systems in smart microgrids. The initial theoretical evaluations are referred to the case study of a laboratory DC microgrid interconnecting: electric mobility, stationary storage systems and renewable energy sources in a smart grid scenario. Specific power architectures for the integration of a 7kWp solar generation system with the considered microgrid are analysed and compared, in terms of efficiency and costs, in order to support the choice and the design of optimal solutions. Modeling and simulations of the related components are carried out in Matlab-Simulink environment in order to evaluate the performance of different embedded maximum power point tracking techniques, working in balanced and unbalanced irradiance conditions for the considered PV generation system. The promising results and the considerations reported in this paper highlight the importance of using the proposed smart power architectures and the related control techniques to support the optimal use of sustainable energy generation systems.

The IGBT active clamp gate driver is a conveniently method used to protect the switch from the overvoltage by driving the gate input of the IGBT itself. The overvoltage is common during the turn-off of inductive loads or circuits with parasitic elements. This clamping circuit is generally embed into the gate driver circuits. The aim of this paper is to study and model the active clamp circuit giving a compact mathematical model for the power losses calculation. The losses calculation are needed for the heatsink sizing when the system is used in not conventional use, with single or repetitive overvoltages, as for example for the solid state circuit breakers (SSCB) without external passive clamp circuits. Moreover the study has been validated with experimental tests.

This paper deals with evaluations on a power architecture for the integration of renewable energy generation systems with the sustainable mobility in a smart grid scenario. Starting from a real case study, represented by a laboratory prototype of a DC micro-grid, analytical considerations are carried out by means of functional models of the main components of the microgrid. The proposed modeling allows the identification and optimization of an energy management strategy, which is specifically evaluated in this paper to reduce electric power supplied by the main grid. The simulation results highlight the good performance and the stability of the proposed strategy during different operative conditions of the micro-grid.

The ultrafast DC charging for Plug In Electrical Vehicles, is very attractive solution for end users, thanks to the opportunity to reduce charging time. The drawback of this solution is the grid impact of this system, due to the high peak power, that impose the use of local energy storages. Another opportunity to help the power grid is to provide ancillary services and use the energy stored into Electrical Vehicles. These functions are called Vehicle to Grid (V2G) and are considered the most promising techniques for the future. In this paper different fast dc charging architectures have been studied and compared each other to select the best solution grid integration, efficiency and costs.

This review present the state of the art of the circuit breaker for photovoltaic applications. The work consider the most used systems for this kind of applications, and in particular, starting from the state of the art of the mechanical Circuit Breaker, introduce the new emerging technologies based on Solid State Circuit Breaker and Hybrid Circuit Breaker. All the proposed systems will be compared each other in terms of robustness, galvanic insulation, intervention time, remote control etc. The study highlight that the Solid State Circuit Breaker are better in terms of protection capability and customization, thanks to the software based sensing method. This allow to design better protections for lines and equipment. For this reason, the authors think that in the future all circuit breaker technology will substitute the sensing hardware with digital based sensing. The last part of the paper introduce a laboratory prototype solid state circuit breaker, build to test different protection methods and understand limits of the digital sensing method. The experimental results confirm the higher performance in terms of accuracy, fast response and customization of the digital sensing if compared with classical hardware sensing.

This work is focuses on the study and the development of a Circuit Breaker (CB) for photovoltaic applications according with the state of the art and standards. The proposed CB is composed by a Solid State Power Controller (SSPC) and a dedicated Digital Signal Processing (DSP) for the real time protection. The DSP communicate via CAN BUS with the main computer to set the protection curve and to remotely open/close the switch. The work has been focused on the measurement of the intervention time of each protection level and the measurement of the execution time of the firmware coded in the fixed point Q15 format.

In this paper, a universal circuit breaker for aeronautic testing is proposed. The aim of the work is to discuss the design and simulations of a circuit breaker that can work with a low/high and AC/DC voltage source. Furthermore, the breaker can work in single or three phase mode synchronizing more devices. Thanks to the high performance DSP installed on board and the general purpose protection system algorithm, the device enables all protective devices used on aircraft to be emulated.

A supervision algorithm of ancillary services for distributed active front-end in a small industrial microgrid is presented. A comparison between distributed and centralized control of the active front-ends aimed to achieve optimal voltage regulation within the grid and minimal harmonic distortion both close to sensible loads and at PCC is performed.

This paper presents the design and the experimental tests of an E-bike 300-W battery charger for a cyclo-station based on wireless power technology. In particular, a series resonant inductive power converter with an E-geometry magnetic core topology is proposed. A mathematical model is developed and a performance analysis is conducted to determine the voltage transfer function, maximum power transfer capability, efficiency for different air-gaps (1–3 cm), and misalignments (0.5–1.5 cm). Also, it is performed analytical and experimental investigations of the minimum and maximum relative frequency points of active input power and efficiency in order to determine how these points changed as the resistance load varied. The results of the analyses indicated that the maximum frequency points of active input power are different from the maximum frequency points of efficiency and the zero-frequency points of reactive input power. This means that maximum power transfer and efficiency conversion are not obtained in correspondence with the resonant frequency. For this purpose, it is conducted a wide frequency characterization of 30–50 kHz around the designed resonant frequency of 40 kHz. An iterative electrical and magnetic design procedure is proposed based on 3D finite element analysis. Simulation and experimental results are presented for a full-sized prototype. The design of the E-bike battery charger is validated in terms of rated input voltage and output power for different air-gap configurations.

This paper presents a type of converter working with high voltage and used for high step down voltage reduction. The converter can be used as the core for the construction of a Power Electronic Transformer (PET). A Single-Star Bridge Cells Modular Multilevel Cascade Converter (MMCC) is used to create a AC/DC or DC/DC converter with high step down voltage ratio. The converter uses LLC resonant converters to transfer the energy from the MMCC cells to the load. Despite the idea to use modular converters for the construction of PET is not new, in the classical PET the control is in charge of the cell voltage balancing and for the second stage the load sharing regulation. The proposed converter can work with a more simple control ensuring the load sharing and the voltage balancing thanks the property of parallelized LLC resonant converters. The work reports simulation results with main parameter variations.

This paper focuses on some aspects of the study and development of an Electrical Power Center (EPC) for aeronautical application tested in a flight demo channel up to 15000 ft (4500 m). The studied EPC is composed of several Solid State Power Controllers (SSPCs) each with a dedicated Digital Signal Processing (DSP) for the real time protection. All DSP communicate via CAN BUS with the main computer where are coded the energy management strategies. The paper reports the developed SSPC protection method with several simulation results. The work describe a typical workflow based on requirements analysis, specs derivation, design phase, physical implementation, testing phase, results analysis versus simulations and final equipment validation for flight.

The paper presents the state of the art and the future trend of the Energy Management. The “Energy Management” term is often used to indicate one or more techniques adopted in the new more electric aircraft, to avoid the generator overload. The designer can use four different approaches, or a combination of them to reduce the over sizing of the generators. The first method regulate the energy exchanged between sources in order to share the power between them. The second method uses storage elements (battery or supercap) to limit the peak power. This elements are connected to the power bus through DC/DC converters that are in charge of the power flux regulation and work like active filters. The third method regulate the loads, or switch them ON/OFF limiting the generator overload. The last method works with the fast reconfigurable network and distribute loads between sources in order to charge each generator within its capability. Some example of experimental works are also provided in the work.