A 6kW, 200kHz boost converter with parallel-connected SiC bipolar transistors

This paper describes issues related to design, construction and experimental verification of a 6 kW, 200 kHz boost converter (300 V/600 V) built with four parallel-connected SiC bipolar transistors. The main focus is on parallel-connection of the SiC BJTs: crucial device parameters and influence of the parasitics are discussed. A special solution for the base-drive unit, based on the dual-source driver concept, is also presented in this paper. Experimental verification of the boost converter with special attention to power loss measurement and thermal performance of the parallel-connected transistors is also shown. The peak efficiency measured at nominal conditions was approximately 98.5% where the base-drive unit causes around 10% of the total losses.