Finite Element Analysis of Si and SiC Power Modules for Accurate Reliability Assessment

Applications of power electronics are rapidly expanding and their utilization has benefitted many industries like power generation, transmission, distribution, traction applications, wind, solar energy generators and aerospace to name a few. Insulated gate bipolar transistors (IGBT) are a key component in power electronic modules today. The reliability of the power module is dependent on the efficiency and proper functioning of major components like the IGBT. These components are, however, exposed to extreme thermo-mechanical stresses due to their operating conditions, thereby generating failures like wear-out fatigue. This paper highlights the effects of thermal cycling of silicon IGBT compared to silicon carbide IGBT. The reliability physics of the power module is presented employing finite element analysis, including simulated power cycling. This work aims to understand the failure mechanisms and associated interdependency between varied cyclic test parameters that could improve the methods employed for prognostics and health management of power modules in critical aerospace systems.