Centralized Short-Circuit Protection of SiC Modules Connected in Parallel
Due to the low short circuit withstanding time, short-circuit protection (SCP) for SiC devices is challenging. The SCP is more difficult when multiple devices are connected in parallel, as the turn-off of one device locally may lead to the overstressing of others. To resolve this, a centralized SCP approach designed for parallel-connected devices is introduced. This method employs the instantaneous current from the common-source inductors in power modules as a key metric to simultaneously reduce the gate-source voltages across all devices. Additionally, the voltage drop across each power device is monitored to enable their timely turn-off. This two-stage strategy ensures a quick response and high noise immunity for SiC devices. The proposed approach, seamlessly integrated with the power converter's controller, has been experimentally validated in a three-phase converter.