A Gain Maximized Gate Circuit Feedback Loop and its Effect on Current Mismatches of Paralleled IGBTs

Inhalt:
When using a common gate drive unit for switching paralleled IGBT modules, a negative feedback loop helps decreasing dynamic current mismatches during turn-on and turn-off caused by unequal IGBT behaviour, as past works showed. This feedback loop can be significantly improved by a low ohmic connection between the gate terminals of the paralleled IGBTs and a high inductive busbar connection between the power emitter terminals. Within this paper the theoretical principle is presented and underlaid with Synopsys Sentaurus Device TCAD simulations as well as with measurement results using 6.5 kV, 1 kA single switch IGBT modules.