A Figure of Merit for SiC MOSFET Power Modules to Achieve High-Power-Density Energy Conversion

Power modules are the core components for energy conversion in motor drive, renewable energy application, and battery electric vehicle (EV) and have a significant impact on system performance and reliability. A variety of packaging structures are proposed for a number of applications, and however, there is no clear guideline for their performance comparison. To help in selection of wide bandgap MOSFET-based power modules for high-power-density energy conversion system, a new power module figure of merit (PMFOM) is proposed in this article. The PMFOM is derived based on device switching behavior, considering the conduction and switching loss, parasitics from package layout, thermal resistance, and package area. Finally, the validation of the proposed PMFOM is verified with a practical design example using commercially available 1.2-kV power modules.