Snubberless high-power rectifiers

Usually, a snubber circuit is put in parallel with a power diode to avoid the occurrence of destructive overvoltages during turn-off. Power rectifiers that do not need a snubber are described. Using numerical simulations from the computer program COMPASS (computer program for the analysis of semiconductors), it is shown that such snubberless rectifiers can be made by controlling the axial carrier lifetime profile in the rectifier. It is possible to choose this profile in such a way that the forward characteristic of the rectifier is not impaired. The absence of a snubber circuit also leads to major electrical improvements. In the snubberless case, the total current switches more than three times faster than in the case of a normal diode with a snubber circuit, and the reverse current peak of the total current is reduced by 33%. The total dissipated power per switching process in the snubberless case is less than half the power dissipated in the normal case