Evaluation of a Next Generation 750 V SiC MOSFET for 400 V EV Powertrain Applications

Abstract:
There are a wide range of powertrain applications that still use a 400 V bus and similarly higher voltage nodes where having high power density is especially important. To address this, a next generation Wolfspeed 750 V SiC MOSFET die is introduced that is 7.2 mOmega at room temperature which is a 25% reduction from the previous generation. A comparison of the static characteristics for a single die and the dynamic characteristics of four die paralleled in a test module are shown. At 500 V and 400 A, the total switching losses are less than 11 mJ. The results are used to do a system level simulation that looks at the impact of the improvements against an IGBT at a similar power level, which is the main competitor in 400 V powertrain applications. The results show that the next generation die has a third of the losses of the IGBT under similar system conditions and the next generation die has an even larger reduction of 18% lower losses over the previous generation die.