Analysis of a New Protection Technique for IGBT using Active Collector Current and Voltage Clamping Method

Abstract

This research presents a new method for protecting semiconductors to improve the availability and reliability of converter or inverter in power electronics systems. The concept involves a newly developed active voltage and current clamping circuit that effectively mitigates IGBT voltage overshoot during short circuit events. This technique controls the IGBT’s collector-emitter voltage during turn-off by partially re-activating the IGBT when its collector-emitter voltage surpasses a predefined threshold. By doing so, the IGBT operates in a linear mode, which slows down the reduction rate of the collector current and minimizes overvoltage across the collector-emitter. Additionally, a high-precision Hall-effect sensor continuously monitors the collector current during short circuits, detecting overcurrent and generating a fault signal in less than 2µs. The integrated voltage and current monitoring system significantly lowers the risk of IGBT failures during abnormal conditions.