SiC OSFETs for Future Motor Drive Applications

This paper investigates the switching performance of six-pack SiC MOSFET and Si IGBT modules for motor drive applications. Both the modules have same packaging and voltage rating (1.2 kV). The three bridge legs of the modules are paralleled forming a single half-bridge configuration for achieving higher output power. Turn-on and turn-off switching energy losses are measured using a standard double pulse methodology. The conduction losses from the datasheet and the switching energy losses obtained from the laboratory measurements are used as a look up table input when simulating the detailed inverter losses in a three-phase motor drive inverter. The total inverter loss is plotted for different switching frequencies in order to illustrate the performance improvement that SiC MOSFETs can bring over Si IGBTs for a motor drive inverter from the efficiency point of view. The overall analysis gives an insight into how SiC MOSFET outperforms Si IGBT over all switching frequency ranges with the advantages becoming more pronounced at higher frequencies and temperatures.