Experimental Test Setup for Thermal Stress Analysis of SiC Devices under Active Short Circuits

This work deals with the thermal stresses analysis of SiC devices operating under active short circuits in electric traction inverters. The last current profile is experimentally emulated through a series RLC circuit, suitably designed and set to emulate the first and most critical time interval of the active short circuit. After having presented the mathematical formulation providing a good approximation of the active short circuit current, a design procedure of the RLC network and experimental tests on 1200V-170A SiC power MOSFETs are provided. The main aim of this work is to provide a tool useful to estimate the thermal stress to which power devices are subjected under active short circuit tests, trying to identify any possible weaknesses in the technology.