Extraction of parasitic inductances of SiC MOSFET power modules based on two-port S-parameters measurement

Abstract

With silicon carbide (SiC) MOSFETs becoming commercial available, high switching frequency is a prevailing trend to increase the power density and efficiency in power converters. Nevertheless, the device performance is critically determined by the values of parasitic inductances, where negative effects such as switching oscillations are usually presented. It is more likely troublesome for power modules due to complex interconnect structures and higher current levels operation property. A parasitic inductances extraction technique based on two-port scattering (S) parameters measurement for SiC MOSET power modules is introduced in this paper. Floating errors in the conventional measurement methods can be avoided and accurate results are revealed from a step by step analysis. The practical utility of the two-port approach is demonstrated through a case study of a 1200V SiC MOSFET power module.