Next generation DC-DC converters for Auxiliary Power Supplies with SiC MOSFETs

DC-DC converters are essential and mandatory components for Auxiliary Power Supplies in rail vehicles. Their further development show huge challenges in terms of weight, volume, noise, isolation, EMC, safety and controllability. This article presents motivation for SiC, comparison of different topologies and results of a new innovative DC-DC converter prototype based on these terms by use of SiC-MOSFETs. The main development goals therefore were switching frequencies above audible level, downsized passive components, high integration, reduced mechanics and cabling, soft switching and reduced interlock times to ensure high power density. At the end the prototype is compared to IGBT solutions.