Novel SiC Power Module for Traction Power Inverters with Low Parasitic Inductances

Automotive industry is moving fast to adopt SiC devices in the next generation electric vehicles due to numerous benefits such as reduced losses, higher blocking voltage, smaller package of power electronics components, etc… A new power module package, which is optimized for traction inverters, is presented in this paper. Electrical layout of power module is optimized, where power loop parasitic inductance is minimized to be 5 nH, enabling fast switching with low voltage overshoot. Complete power stage, including power module and dc bulk capacitor, is designed to achieve low inductance of only 5.5 nH. New reverse conducting 900V, 10mΩ SiC MOSFETs from Wolfspeed are used in this power module, reducing conduction and dynamic switching losses. Power module can deliver 250 kW of active power, while achieving high overall efficiency of 98.5%. Performance merits of the new power module design are verified experimentally through extensive static and dynamic characterization. The new SiC power module is an excellent package for automotive applications, enabling operations at higher switching frequencies and resulting in smaller power conversion components.