A Self-Regulating Gate Control based on the Parasitic Turn-On Effect for Low Losses and Low EMI of SiC MOSFET

Abstract:
This paper introduces an intelligent-gate-driver-based self-regulating gate control approach that utilizes the parasitic turn-on effect (PTO) to realize low switching losses and low electromagnetic interference (EMI) at SiC MOSFET turn-on. This approach controls the PTO by adjusting a specific gate control parameter and measures only one signal, the voltage between power source and kelvin source for EMI evaluation. It is verified by measurements that with this approach the PTO is fully controllable and the gate control parameter can be automatically optimized for varying operating conditions of a continuous operation according to the EMI evaluation. The total turn-on and reverse recovery switching losses of the continuous operation are reduced significantly while accomplishing low overvoltage and reduced oscillation of the complementary freewheeling device. This approach provides additional advantages like low-cost, low calibration, hardware and measuring efforts.