Novel electro-thermal coupling simulation technique for dynamic analysis of HV (hybrid vehicle) inverter

This paper describes a novel electro-thermal coupling simulation technique mainly focused on the dynamic analysis of the HV inverter during WOT (Wide Open Throttle) operation. This technique can predict the junction temperature of power devices installed within the power module accurately. This simulation technique is composed of an inverter circuit model including power semiconductor device models, a novel compact thermal model suitable for automotive power modules and motor model. Various information and conditions such as motor current, motor rotation speed, switching frequency and variable DC-link voltage are applied to the simulation for carrying out the WOT operation. The comparison between the simulated and measured results indicates that this method offers reasonable accuracy for the IGBT temperature estimation where the worst case error in the IGBT temperature is less than 10 deg-C. It takes 210 min to complete the WOT simulation with duration of 4 seconds.