High Frequency Hard-Switching Isolating DC-DC Converter for Auxiliary Power Supply for Trolleybusses

Among the most important requirement on converters used within a structure of auxiliary power supply (APS) generally in the area of light traction belong the size and total mass as they are usually placed in a spatially limited container. Increasing switching frequency and employing latest low loss and high-speed switching devices is one of the ways how to shrink converters size and thus increase power density. This paper describes hard switching 11kW DC/DC converter built on SiC JFET transistors working at 100 kHz with triangular current waveform which is supposed to provide isolation function within the APS. Practical results and experimental verification of a laboratory prototype are presented as well.