Power Loss Analysis of Powertra in Inverter with SiC MOSFETs and Si IGBT for 400V and 800V Battery Voltage

The mainstream battery voltage of electric vehicles is increasing from 400V to 800V. This higher voltage class brings significant benefits, including faster charging speed, higher power density, and increased efficiency. With the increase in voltage class, SiC MOSFETs are becoming the primary choice for powertrain inverters. This paper investigates the power losses of powertrain inverters using both SiC MOSFETs and Si IGBTs, operating under both 400V and 800V battery voltage classes. Through analysis of power losses and efficiency comparisons under various application conditions, it is demonstrated that SiC MOSFETs offer greater efficiency benefits under low-speed and light-load conditions. Mission profile based motor drive simulation results validate these findings.