Influence of Open Switch Failure on Normal Devices in HANPC Inverters

Abstract

This paper analyzes the normal switches losses under open switch failures in three-level hybrid active neutral point clamped (HANPC) inverters. Three-level HANPC inverter has numerous Si-IGBTs and SiC-MOSFETs to improve the output quality. However, the three-level HANPC inverter has high percent of switch failures due to using many switches. When the switch is under a short fault, the inverter system should be shut down thought overcurrent detection. On the other hand, the open switch failure is difficult to detect depending on fault-switch location. In addition, the output quality is worsened and other devices get damages. The switch losses after open switch failure are analyzed to prevent the secondary switch failure in the future. The simulation results demonstrate the influence of switch devices considering the various open switch failure scenarios