Dynamic Performance Comparison of SiC Power Modules With and Without Schottky Diode Operating from 25 to 250°C Junction Temperature

To expand the application of SiC power devices in higher temperature, the dynamic performance of SiC half-bridge power modules with and without SiC Schottky barrier diode (SBD) is evaluated in detail with the temperature from 25 °C to 250 °C. First, two SiC power modules with different configurations are designed for high temperature tests. Second, their switching characteristics are characterized via multi-pulse tests with various load currents and temperatures. It is found that the SiC power module with SBD (PMWS) shows a larger switching energy loss at the room temperature due to its increased parasitic junction capacitance. Additionally, at a high temperature such as 250°C, the switching performance of SiC power module without SBD (PMWoS) deteriorates a lot because of the significantly degraded reverse recovery effect, which brings higher energy loss and more severe overvoltage during a fast turn-on switching process. Third, two schemes to suppress the SiC MOSFET turn-on overvoltage, i.e., increasing the turn-on gate drive resistor and decreasing the dead time, are evaluated under high temperatures. Both schemes are verified to be capable of effectively improving the dynamic performance of SiC PMWoS at a high junction temperature without bringing any extra cost.