Short Circuit Protection of a Power Module with Trench-SiC-MOSFET. Can DESAT be Fast Enough?

Due to their high short circuit current and lower short circuit withstand time in comparison with Si-IGBTs, SiC-MOSFETs require a fast and precise short circuit detection method. For this purpose, experimental short circuit detection and protection results of a newly developed power module using the conventional drain source monitoring method (a.k.a. DESAT) are presented. Results show that even considering the latest generation of SiC devices, DESAT detection is still capable of providing protection against short circuit events. The device under test used for this investigation was a power module for e-powertrain applications equipped with ROHM’s newest generation of SiC trench MOSFETs. Furthermore, the benefit of a novel soft turn off method and its influence on the total short circuit time and energy is discussed.