Turn-On Transient Modeling of 10 kV SiC MOSFET Half-Bridge Power Module in LTspice

Medium-voltage SiC MOSFETs (> 3.3 kV) feature high breakdown voltage and fast switching speed. During the turn-on transient of 10 kV SiC MOSFETs, drain-source voltage drops from 6000 V (rated voltage) to 0 V within hundreds of nanoseconds. In this paper, an improved device modeling approach is proposed to describe the turn-on transients of medium-voltage SiC MOSFETs, with the consideration on the short-channel effect, the threshold voltage hysteresis effect, and the soft-transient characteristics. A custom-packaged power module in a half-bridge configuration, where each switch position contains a single 10 kV SiC MOSFET die (QPM3-10000-0300), is modeled and simulated in LTspice as the case study. Compared with the double pulse test experiments at several operating points, the proposed simulation model for 10 kV SiC MOSFET module can provide more accurate dv/dt, di/dt behavior compared to the traditional model with only static characterization.