Electrical Insulation Design and Accurate Estimation of Temperature via an Electrothermal Model for a 10 kV SiC Power Module Packaging

Abstract

Wide-bandgap (WBG) power devices can tolerate higher currents and voltages than their silicon (Si)-based counterparts. However, the realization of their superior characteristics is tied to the reliability of their packaging, where thermal management and reliable electrical insulation design are the most challenging tasks to this end. Not taking care of the former one leads to thermal runaway, and the latter one causes the electric breakdown of the whole module. In this paper, the packaging design of a 10-kV SiC diode is studied by addressing both challenges above. Electrical insulation design is carried out through a finite element method (FEM) electric field calculation model developed in COMSOL Multiphysics, meeting both the one-minute insulation and PD tests based on IEC 61287–1. Through developing an electrothermal model and for considered dimensions, an accurate estimation of the junction temperature is obtained to determine the maximum load current of the module.