Common-Mode Noise Current Simulation and Measurement on a Gate Driver for SiC MOSFET Half-Bridge Modules

Fast switching transitions of the SiC MOSFET power semiconductor devices, can cause abundance of issues due to injected common-mode (CM) noise current through gate driver, possibly preventing converter successful operation. Therefore, this paper presents a detailed methodology of simulation and new measurement method of CM noise current on a gate driver. For simulation, detailed consideration of circuit parasitics (inductances, resistances and capacitances) is included and analyzed. Considering measurement, small high-precision chip resistors are utilized to measure the CM noise current. The results achieved by simulation and measurement are in agreement. This method is applied to design a novel gate driver for 1.7 kV SiC MOSFET half-bridge module having "on-board communication" between top and bottom devices. By comparing different options, simple communication by a digital isolator is deemed the best. As this paper illustrates, proposed method of evaluating and measuring the noise is useful to design new gate drivers.