A power electronics module and a method of protecting a solid state switching device in a power electronics module

摘要

A solid state switching device M1 (e.g. MOSFET, IGBT) in a power electronics module (e.g. inverter) is protected in the event of a short circuit fault. The power electronics module includes; at least one solid state switching device, a gate driver, a controller and a current limiting diode D1. The controller provides a gate signal to the gate driver. The gate driver connects to, and provides a drive input to, a gate terminal of the switching device to activate the switching device. The current limiting diode is connected in parallel between the gate driver and the switching device and is connected to ground via a fault protection switch S1. The fault protection switch is activated in the event of a short circuit fault and protects the switching device by limiting the current received by the switching device. A fault detector includes a comparator that compares a voltage received from a collector terminal of the switching device against a threshold voltage. If the voltage exceeds the threshold, a control signal indicating a short circuit fault is used to trigger the fault protection switch. The controller may assess the severity of the fault based on the voltage. If the fault exceeds a shut-down threshold, the gate driver and, thus, the switching device is disabled.