Overcurrent and Short-Circuit Protection Method using Desaturation Detection of SiC MOSFET

This paper present overcurrent and short-circuit protection methods for medium voltage silicon carbide(SiC) MOSFETs. Contrary to other protection methods such as a Rogowski coil, the desaturation detection can be simply designed and applied to the general gate drivers. Thus, this paper proposes the design of the desaturation detection circuit. In order to achieve fast protection performance, additional issues of desaturation detection were described. In the end, the protection circuits are evaluated in short-circuit and overcurrent with the 1200 V SiC module and 1700 V SiC discrete.

I. Introduction

Wide-bandgap semiconductors, such as silicon carbide metal-oxide-field-effect transistors (SiC MOSFETs), has advantages like high breakdown voltage, fast switching speed and performance in high temperature [1]–[4]. SiC MOSFETs are now available with blocking voltage up to 1.2 - 10 kV medium voltage(MV)[5]. Due to high insulation voltage, SiC MOSFETs are now widely used in many high power MV applications like solid state transformer (SST), multi-level modular converter (MMC) and space application [3].