Flyback-based high-side gate driver for a 10-kV SiC MOSFET

Aside from providing voltage and current of sufficient values, a gate driver of a SiC MOSFET must also be durable enough to keep operating properly in given place of a main circuit of a converter. A high-side SiC MOSFET constitutes a challenge to being driven properly, since a high-voltage potential becomes repetitively applied at an output of the gate driver. In order to limit a resulting flow of parasitic current Cdv/dt to ground of the driver, a low-capacitance isolation must be implemented. Presented in this paper is a flyback-based gate driver, which is dedicated for driving a high-side 10-kV SiC MOSFET. Required properties of the gate driver such as high dielectric strength and low input-to-output stray capacitance were evaluated through a series of measurements. Switching voltage values and switching speeds of the driver were examined in an 800-V double pulse test with a 1.2 kV SiC MOSFET and compared with two other devices potentially capable of operating with the 10-kV SiC MOSFET.