Enhanced Dynamic Active Discharge Approach for SiC MOSFETs Utilizing Advanced Gate Drivers

Inhalt:
Applications like electric vehicle (EV) drive inverters with large DC-link capacitors need a mechanism to safely discharge these energy storage components to prevent safety hazards. Silicon carbide (SiC) MOSFETs are commonly used in electric vehicles (EVs) for their superior performance, eficiency, and power density. However, they face challenges in control and protection due to their limited short- circuit withstand time (SCWT). This paper presents a novel active discharge method that utilizes a current-controlled gate driver with a gate current shaping feature, speciically designed for optimized usage of SiC MOSFETs. This method employs a SiC MOSFET half-bridge path during high-current discharge operations, adjusting the gate current at different switching stages to ensure robustness and enhance reliability. The innovative gate driver architecture improves electromagnetic compatibility (EMC) performance, reduceshardware requirements,and lowersoverall systemcosts.