Strategies of fault tolerant operation for three-level PWM inverters

This paper proposes fault tolerant operation strategies for three-level neutral point clamped pulsewidth modulation inverters in high power, safety-critical applications. Likely faults are identified and fault tolerant schemes based on the inherent redundancy of voltage vectors are presented. Simulation verification is performed to show fault handling capabilities. Prototyping and principle investigation are performed on a 150-KW inverter and testing results are presented.