Dominant Model Parameter Extraction for Analyzing Current Imbalance in Parallel Connected SiC MOSFETs

This paper presents a general method to extract dominant device model parameters for analyzing the current imbalance of parallel-connected Silicon Carbide (SiC) metal-oxide-semiconductor field-effect-transistors (MOSFETs). The proposed method is based on a sensitivity-based analytical equation, referred to as N-devices forward propagation of variance (NFPV). Using NFPV, we can accurately and efficiently calculate the energy loss variation as the function of model parameters and their correlations of the N-paralleled devices. The NFPV enables us to quantify contributions of each model parameter to the energy loss variation due to the current imbalance. Experimental results using measured current-voltage characteristics of SiC MOSFETs demonstrate that the proposed method efficiently found the two most important model parameters, with which the energy loss variation is reproduced.