IGBT Modules - Technologies, Driver and Application (Second Edition) - page 317

Fig. 7.11
Simulation of SC1 andSC2 short circuits
Another critical situation arises when the IGBT does not reach the saturation voltage
after turning onto anSC2 short, due to an insufficiently designeddriver stage and,
hence, before the short circuit monitor turns off the IGBT. An example of this is detailed
Due to the slow turn-on process, the IGBTdoes not reach saturation rapidly
and remains in the active region instead, at the time when the turn-off signal arrives at
the gate. The result is the destruction of the IGBT. As a countermeasure, it is
recommended usinga driver stage, which turns on the IGBT in less time by:
lower gate resistor (cannot be recommended unconditionally)
less gate-emitter capacitance (if implemented)
fast switching driver stage (optimisation of the booster stage)
reduction of the internal driver impedance (hence increasing the peak gate
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