First Fault-Resilient High-Power 5-Level Flying Capacitor DC-DC Converter with Ideal Short-On Failure IGBT Modules

Fault-tolerance is a common measure to improve power electronics reliability. Multilevel DC-DC converters offer inherent redundancy but require for fault-tolerant operation an ideal short-on failure semiconductor. This paper presents a suitable IGBT package which fails short with less loss than in normal continuous-on mode and is capable of conducting nominal current for a sufficient period of time. A 5-level Flying Capacitor Multilevel Bidirectional DC-DC Converter for 1000V to 400V conversion is designed with these IGBTs. The converter operation in normal mode, reconfiguration after failure and operation in degraded mode after an IGBT failure with 10kW power rating are shown.