Transient thermal management of SiC power modules by an in-built thermal buffer layer

Abstract

A numerical investigation has been conducted to improve the transient thermal performance of SiC modules during varied loads, and phase change materials is utilized as a thermal buffer layer and integrated into SiC modules under SiC MOSFETs. The influences of PCM on the instantaneous overload capacity and temperature fluctuation during power cycle have been explored. As for the overload capacity, PCM could protect SiC modules from over-heating under a 1.5 per unit heat flux as high as 500 W/cm2 for over 10 s, which is critical for safety of power system under the short-circuit faults. While for power cycles, SiC modules exhibits a much lower temperature swings when tp < 20 s, and the maximum reduction could achieve 12 K. Additionally, the geometries of PCM containers makes a great differences on the transient temperature responses of PCM-integrated modules, and special attention should been given to balance the heat absorption and thermal resistance of PCM. In the present work, a container with branch-like fins shows the best thermal performance for both overload conditions and power cycles.