Realising SiC MOSFET switching speed control based on a novel series variable-resistance gate driver

Silicon carbide (SiC) MOSFETs feature salient characteristics such as higher breakdown voltage, lower losses and higher switching speed when compared to Silicon (Si) MOSFETs. However, due to the high switching speed and parasitic parameters, the SiC MOSFET turn-on and turn-off dynamics lead to overvoltage, overcurrent and electromagnetic interference (EMI) issues. This paper proposes a SiC MOSFET switching speed control concept based on a gate driver that features dynamically changeable gate resistance allowing microcontroller-based adjustment of the SiC MOSFET switching speed. This function therefore enables a closed-loop SiC MOSFET switching speed control, which is suited to device safety and EMI control. The configuration and operation of the proposed concept are presented. Both simulation and experimental results are provided to verify the proposed circuit.