The direct series connection of SiC MOSFETs

Silicon Carbide (SiC) MOSFETs offer high speed switching for power applications at high blocking voltage ratings, e.g. 1.2 kV, 3.3kV and more in the future. Connecting SiC MOSFETs in series is of interest to achieve AC distribution voltage levels. This paper presents experimental results of SiC MOSFETs from two different manufacturers switching independently in the series connection. The results indicate that the switching of SiC MOSFETs in the series connection is attractive, with no need for active control systems or passive snubbers to obtain an evenly distributed voltage sharing. The intrinsic characteristics of SiC MOSFETs, the nature of the ringing at turn-off and the voltage sharing at turn-on are discussed.