Hybrid Driving Strategy of SiC MOSFETs Buck Converter With Switching Losses Reduction and Safe Operation

This paper presents a hybrid gate drive strategy for optimizing the performance of Silicon Carbide (SiC) MOSFETs in power converters. The proposed method dynamically switches between a current-source gate drive (CSG) mode and a voltage-source gate drive (VSG) mode based on the load current. Under light-load conditions, the CSG mode is utilized to maximize switching speed and minimize switching losses, while under heavy-load conditions, the VSG mode is activated to mitigate overvoltage stress by slowing down the device transitions. The strategy provides a significant reduction in switching losses, especially at light loads, while ensuring safe operation during heavy-load conditions. Experimental results on a 1000 W non-synchronous buck converter demonstrate the effectiveness of the proposed approach in improving both efficiency and overvoltage protection.