Energy loss analysis of traction inverter drive for different PWM techniques and drive cycles

The critical components in electric vehicle (EV) propulsion system are the traction inverter and motor. For better performance of the EV, it is important to operate traction inverter/motor at optimal efficiency points over the entire drive cycle. The significant advances in pulse width modulation (PWM) techniques has helped to improve the efficiency of the traction drive. Hence this paper aims at the modeling of the traction inverter with different PWM techniques, over different city driving schedules and analyze the energy losses in the semiconductor devices. The paper presents the thermal model based analysis of DC/AC inverter considering the conduction and switching losses for both insulated gate bipolar transistor (IGBT) and antiparallel diodes as a switch. An induction motor driving a medium-sized EV, has been modeled in the PLECS software. The energy loss calculation is carried out based on device characteristics. The losses are observed for both cold start and hot starts, based on the heat sink temperature.