This digest introduces a novel online monitoring technique for SiC MOSFET gate oxide degradation, based on frequency spectrum characteristics extraction of transient gate voltage during the turn-ON process. By leveraging the original output of the driving IC as the trigger signal, our method automates the monitoring function, irrespective of the switching duty cycle or frequency. The approach is sampling-friendly and cost-effective, eliminating the need for additional isolation barriers and offering seamless compatibility with most commercial drive ICs. The experimental validation shows that the significantly increased output voltage (25.6%) can accurately monitor the degradation of the gate oxide. Additionally, the practical applicability of this method is demonstrated through the testing in a single-phase inverter.
