Robustness of SiC MOSFETs Design Under Repetitive Short Circuit and Avalanche Cycles Stress

Abstract:
The reliability of power conversion systems is critical, particularly in the presence of short-circuit and avalanche events. For instance, the degradation of the load winding insulation or unclamped inductances of PCB traces and cables can have significant consequences. As the industry transitions from siliconbased to wide bandgap-based power conversion systems, ensuring the ruggedness of SiC MOSFETs under repetitive fault operating conditions is essential. Our research has revealed that among the three main SiC MOSFET designs available in the market - planar, symmetrical, and asymmetrical trench - only the asymmetrical trench design demonstrates full ruggedness against repetitive fault operating conditions, making it a crucial consideration for the development of reliable wide bandgap-based power conversion.