SiC MOSFET Switching Waveform Profiling Through Passive Networks

The use of Wide Band Gap (WBG) devices in high performance power converters is becoming more common, and the range of techniques for managing the high speed switching transitions is broadening. In particular, there is now a greater interest in applying techniques for shaping the switching transients to improve the converter performance. This paper explores the current state of the art in waveform profiling gate drivers and their application to WBG devices to determine the optimum gate waveform profile. This profile is then analysed with the goal of creating a passive gate drive network capable of replicating the performance. A hardware prototype of this gate driver is demonstrated and experimental results from it are compared with those from a standard drive and a fully active driver. The active gate driver shows a 31% decrease in current overshoot or a 35.4% reduction in turn-on switching losses.