Double- and Single Gate Desaturated Turn-off of Low Saturation IGBTs for Reduced Turn-off Losses

Abstract:
In this paper, the advantages of single- and double gate desaturation pulse-based turn-off of modern low-saturation IGBTs in reducing turn-off energy losses are reiterated. Measurement results on experimental 1.2 kV low-saturation IGBTs are presented where it is shown that double gate desaturated turnoff leads to up to 48% reduction in turn-off energy losses compared to 31% in single gate desaturated turn-off. A comparative study of the two methods is taken up with the objective of determining the benefit of the double gate method, and the similarities and differences between the double and single gate desaturated turn-off methods. TCAD device simulation results with devices of different voltage classes are presented to corroborate these findings as well as to emphasize that the potential to reduce turn-off energy losses is even higher for IGBTs of higher voltage classes.