A power electronics module and a method of detecting a fault in a power electronics module

摘要

A power electronics module (e.g. inverter) includes at least one solid state switching device M1 (e.g. MOSFET, IGBT), a gate driver, a controller and a fault detector. The gate driver connects to, and provides a drive input to, a gate terminal of the switching device to activate the switching device. The controller provides a gate signal to the gate driver. The fault detector includes a capacitor (e.g. external Miller capacitor, CM) connected to a collector terminal of the switching device and a comparator connected to the capacitor. The comparator compares a voltage received from the capacitor against a threshold voltage. If the voltage exceeds the threshold, a control signal indicates a short circuit fault. The control signal may activate a fault protection circuit which reduces the current and/or voltage received by the switching device. The capacitor may be further connected to the controller via an isolation circuit. The controller may assess the severity of the fault, based on the signal received from the capacitor via the isolation circuit and, if the fault exceeds a shut-down threshold, the gate driver and, thus, the switching device is disabled.