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 Channel Potential Modification induced Displacement Current during the Trench-Gate IGBT Switching

Authors & Affiliations

Xing Liu and Thomas Basler
Chair of Power Electronics
Chemnitz University of Technology



During the switching process of the IGBT, the Miller plateau can be observed on the gate voltage waveform. The present understanding of the Miller plateau is the Miller capacitor induced displacement current at the collector-emitter voltage transient, which is compensated by the gate current from the driver unit. Hence, the gate voltage remains constant.

In this paper, a novel finding of the Channel Potential Modification induced Displacement Current (CPiC) is proposed. It has been found that during the Miller plateau, the displacement current is not only provided by the Miller capacitor, but also by inner parts of the gate-emitter capacitor due to the channel potential modification. This novel finding extends the existing descriptions for the IGBT switching behavior and provides a more comprehensive understanding of the Miller plateau.


IGBT, Hard Switching, Miller Effect

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