Optimized Integrated EMI Filter Design in SiC Power Modules with Terminal Inductor for Better High-Frequency EMI Suppression

Using fast-switching wide-bandgap devices such as SiC MOSFETs can reduce switching losses but also bring more serious common-mode (CM) electromagnetic interference (EMI) problems. Integrating EMI filters directly in SiC power modules is an effective way to solve this problem. However, the parasitic inductance of the Y capacitor branch will affect the filtering effect of the integrated filter. To solve those problems, this paper analyzed the influence of these parameters on the insertion loss of the integrated filters. Then, a terminal inductance structure is proposed according to the results of the analysis, using the mutual effect to cancel the parasitic inductance. The optimized SiC power module with an integrated EMI filter has been designed to achieve lower CM EMI in the high-frequency range.