Implementation of SiC inverter for high frequency, medium voltage applications

Abstract

This paper describes the experiments with a custom build high frequency SiC inverter. The inverter uses the CCS050M12CM2 module with SiC MOSFET (1200V, 50A). A comparison of SiC MOSFET and Si IGBT modules both from datasheets and different scientific papers showed that SiC MOSFETs have higher efficiency, smaller losses and are capable to work with higher frequency than Si IGBTs. The characteristics of SiC MOSFET and Si IGBT inverter were measured in our laboratory and showed that SiC MOSFET had smaller power static losses and switching losses than Si IGBT, SiC MOSFET had higher efficiency and can operate under higher switching frequency than Si IGBT. The switching characteristics of SiC module have been measured up to a frequency of 30 kHz. The problem of gate-source voltage overshoot is considered here; it is caused by parasitic capacitances and inductances. The correct value of damping resistor is tuned to suppress overshoot.