Design of a High Power SiC MOSFET Parallel Active Current Sharing Method Based on di/dt Current Detection

Controlling the current balance of the parallel branch of SiC MOSFETs can effectively avoid their safety problems caused by parallel uneven current. In this paper, we analyze the influencing factors of parallel uneven current from device parameters, power loop parameters and drive loop parameters, and propose a parallel active current equalization method based on the combination of gate voltage delay compensation and dynamic voltage compensation with di/dt current detection from the drive circuit design of high-power SiC MOSFETs, and verify the proposed method by simulation software and double-pulse experiments, and the results show that the results show that the parallel active current sharing method can reduce the maximum current error in the turn-on process from 90A to about 20A and the current error in the turn-off process from 50A to about 25A under the condition that the output current of a single module is 160A, which provides a new method to improve the current balance in the module branches.