Requirements of short-circuit detection methods and turn-off for wide band gap semiconductors

摘要

This paper adds some new results on the short circuit (SC) robustness of novel wide bandgap (WBG) devices presented in [1-3] for 1.2 kV SiC MOSFETs but also for other voltage classes relevant for traction application. Also different short-circuit (SC) detection methods will be evaluated with regard to their application in traction converters using either conventional Si-based or novel WBG semiconductors. In order to derive the necessary requirements for the best suitable SC detection method the SC robustness of silicon based IGBTs, planar SiC MOSFETs and GaN HEMT was evaluated. For this comparison commercially available devices of different voltage classes ranging from 600 V to 1.7 kV are measured under SC type one in order to find the critical energy, which will destroy the device. The mechanisms of failure were also analysed. Together with further criteria like the gate-oxide stability different SC detection methods are evaluated with regard to whether they meet the derived detection requirements of WBG devices.