An Accurate Subcircuit Model of SiC Half-Bridge Module for Switching-Loss Optimization

The increasing demand for high power density requires the power converter to operate in high switching frequency. Silicon carbide (SiC) power module is regarded as one of the most promising candidates for high-frequency applications due to the superior switching speed and low switching loss. With the increase of switching frequency, the switching loss will be the limiting factor of efficiency. Hence, it should be minimized during each switching transition. The optimization of switching loss is normally achieved by the repetitive double pulse test experiments. It is time-consuming to find an optimum gate resistance to achieve the tradeoff between switching loss and electromagnetic interface. In this paper, an accurate subcircuit model for SiC power module is proposed to assist optimization of switching loss in converter design. By considering the device physics and structure, an accurate Miller capacitance model is obtained. Moreover, a parameter extraction procedure is presented, which is based on the datasheet. Good agreements are achieved between the PSpice simulation and experiment.