Influence of Different Load Currents on a Stepwise Driver for Optimized IGBT Turn-Off Performance

Inhalt:
This work presents a multiple stage gate driver based on a switched resistor topology for an insulated-gate bipolar transistor (IGBT). An optimization algorithm is used to find the optimal driver setup where the turn-off switching losses are minimal. A reduction of up to 33% compared to a reference driver, while maintaining equal device stress is reached. As the timing of the optimized driver profile depends on the load current, the effect of the load current on the turn-off event using a stepwise driver is examined experimentally in a double pulse test. This study shows that the optimized driver profile of a stepwise driver can only be reasonably applied for small deviations in the load current. Otherwise, increased voltage overshoots and larger switching losses will occur.