SiC power MOSFET in short-circuit operation: Electro-thermal macro-modelling combining physical and numerical approaches with circuit-type implementation

The purpose of this paper is to describe, for the first time, a global transient electrothermal model of (SiC) power MOSFETs during accidental short-circuit (SC) operations. The developed models allow to analysis an inverter-leg malfunctioning. A thermal model of the SiC MOSFET dies combined with extensive experimentations allow to develop models of the gate leakage current and of the drain saturation current during SC events. After verifying the robustness of the proposed elementary models, an original global circuit model with an easy implementation using a commercial circuit simulation tool is proposed and discussed. This circuit model can be used in order to develop protection schemes against SC faults.