A Screening Method for Improving Transient Current Sharing of Paralleled SiC MOSFETs Based on Spectral Clustering

SiC MOSFETs are often used in parallel in power modules to increase current capacity, but due to mismatches of circuit parasitic inductance and chip parameters, there is a serious transient current imbalance (TCI) between paralleled chips during dynamic processes. Thus, this article proposes a chip screening method based on spectral clustering algorithm which comprehensively considers the differences in parasitic parameters and the differences in chip parameters, aiming to optimize the transient current sharing through the mutual compensation of these two impacts. First, the effect of parasitic inductance and chip parameter on TCI is analyzed. Then, the joint simulation of MATLAB and LTSpice is conducted based on the Spice model and parasitic parameter network, establishing a data set reflecting the relationship among chip parameters, parasitic inductance and TCI. After which, the principle and procedures of the chip screening method based on spectral clustering are presented and derived in detail. Finally, the experimental results validate the effectiveness of the proposed method.