Three-phase SiC inverter with active limitation of all MOSFETs junction temperature

Estimating the junction temperature of power electronic devices is of paramount importance for assuring the reliable operation of power converters. Wide bandgap devices, that allow extremely high-power density levels, make thermal management even more critical than before. Despite the efforts of the scientific community, this problem is far from being solved. Techniques based on thermo-sensitive electrical parameters are gaining momentum in the scientific literature, although their application to real case scenarios is slowed down by many unsolved challenges. The aim of this paper is to present a three-phase SiC inverter capable of accurate junction temperature estimation for all the SiC power MOSFETs and of active limitation of the maximum junction temperature. The temperature estimate is based on the well-known correlation between the conduction resistance and the junction temperature of a semiconductor. It is implemented here on a 3-phase SiC inverter for racing cars used in formula SAE electric student competitions. The experimental results show the effectiveness of the proposed technique in terms of augmented reliability and augmented performance of the power converter.