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This paper studies experimentally the benefits of silicon carbide based power semiconductor technology in a low-voltage grid connected three-phase three-wire pulse width modulated rectifier. The power semiconductor module used in the study is a custom-made 1.2-kV 100-A fully silicon carbide based half-bridge type module designed for fast switching speeds and high temperature operation. The experimental tests are carried out with a 40-kVA prototype system built in the frame of a commercial low-voltage motor drive unit. In addition, the impact of the high switching speeds enabled by the silicon carbide based semiconductor devices on conductive electromagnetic emissions are also investigated. The results show that the conversion efficiency can be significantly improved with silicon carbide compared to the state-of-the-art silicon based semiconductor technology. As a drawback, the faster switching speeds increase the conductive electromagnetic emissions to some extent.

A novel method using gate overdrive is suggested to avoid explosion of IGBT modules in converters. With this method, the gate drive impedance is set to low (∼0 Ω), such that the driving capability of the gate drive is not limited by the short-circuit present between the gate and auxiliary emitter terminals of a damaged IGBT. Using the implemented gate driving concept, the fault current can be redirected through good chips in the module and the current concentration in the faulty chip of the IGBT module could be reduced to avoid explosion.