Medium voltage power switch based on SiC JFETs

This paper presents a high performance cost-effective medium voltage power switch based on the series-connection of low voltage SiC normally-on JFETs using an innovative approach. A prototype module of the proposed switch is experimentally demonstrated having an on-resistance of 127 milliohm and a blocking voltage above 4,500V at room temperature. The prototype module is capable of very low switching losses. Under a 3kV-54A inductive load, the turn-on rise time is 73ns and the turn-off fall time is 37ns; the turn-on energy loss is 14.8mJ and the turn-off energy loss is 1.5mJ. The prototype module is constructed with reliable, proven and commercially available SiC and Si parts, ensuring the high reliability on the component level. This approach exploits all of the advantages of SiC material in a cost-effective way, allowing quick widespread adoption of SiC technology in next generation high-frequency power conversion and motor control applications.