High-voltage high-frequency inverter using 3.3kV SiC MOSFETs

High voltage SiC MOSFETs enable high switching frequency operation that would otherwise be only possible with more complex architectures such as multilevel or interleaved inverters. In this paper, a full bridge inverter using 3.3kV SiC MOSFETs is presented to achieve high-voltage (2100V dc bus), high-frequency (62.5kHz) operation with a simple hard switching PWM technique. The switching characteristics of the 3.3kV SiC device are presented and the effect of the parasitic parameters is analyzed in details. The analysis shows that the tiny stray output capacitor, which is mainly introduced by the bus-bars implemented with a PCB, can have a significant impact on the switching waveforms of the SiC devices. The reported experimental results validate the performance of the proposed inverter.