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This paper presents a new ultrafast dc solid-state circuit breaker (SSCB) that uses a silicon carbide cascode as the main switching and limiting semiconductor and an isolated photovoltaic driver to control it. The proposed topology is self-powered and fully implemented with discrete parts. The SSCB's cascode can work in three different states—fully on during nominal operation, linear mode for current limitation, and fully off to disconnect the load. The time the SSCB operates in linear mode and the maximum current limit is easily set by discrete components. Control inputs have also been included to reset the SSCB after a fault has been removed or to remotely switch it on or off. This device can be used in dc distribution avoiding deterioration due to the problems associated with electric arcs and mechanical aging of moving parts, limiting inrush currents and also minimizing conduction losses respect other kind of circuit breakers. Functional, thermal, and efficiency tests have been carried out with three different 380 V prototypes. Experimental results show the excellent behavior of the SSCB, it is able to block a 380 V short circuit failure in 570 ns; the authors have not found any faster results in the literature. [ABSTRACT FROM AUTHOR]

This paper presents a System-on-Chip design for real-time satellites photovoltaic curves telemetry. In these applications, the limitation of memory and communication bandwidth makes quite difficult to store and to transmit the whole characteristic current-voltage (I–V) curve of any solar section in real-time. The proposed solution is based on the real-time calculation of the equivalent single-diode model of the solar section. The single-diode model fits accurately the behavior of any solar panel, so once the parameters are calculated, saved, and transmitted, at any working conditions, that specific curve could be later reproduced. The system is based on a LEON3 32-bit microprocessor core implemented in a Field Programmable Gate Array. The LEON microprocessors were originally designed by the European Space Agency, Paris, France, to be used in space projects where high reliability is required. In addition, in order to design the system as simple and reliable as possible, from all the methods available in the literature to extract the five parameters of the equivalent model, the Oblique Asymptote Method has been chosen for its simplicity and precision. Finally, some experimental results are presented to demonstrate the accuracy of the final system. [ABSTRACT FROM PUBLISHER]

This paper describes the implementation of a hybrid energy storage system (HESS) using ultracapacitors (UCs) to protect the batteries of an electrical vehicle (EV) from high-peak currents and therefore extend their lifetime. A field-programmable gate array (FPGA) controlled interleaved bidirectional buck–boost converter working in a discontinuous conduction mode, has been designed to transfer the energy between the batteries and the UCs. The FPGA is responsible of generating all the converter gate signals and implements the control stage needed to smooth the battery current peaks. The control strategy is based on dividing the current demand of the motor into two parts (high-frequency current and low-frequency current), the batteries supply the low frequency part and the UCs supply the high-frequency part. Experimental tests have been carried out driving the EV under different scenarios. Experimental results demonstrate the good behavior of the proposed HESS, although the potential battery life extension is still under quantification. The consumption of the EV has been increased due to the converter losses, this increase is minimum under typical driving scenarios, but is quite important in start–stop driving cycles. [ABSTRACT FROM AUTHOR]