Fault tolerant Active Neutral Point Clamped inverter: Short-circuit and open-circuit failures

This paper investigates the fault-tolerant capacity of a modified three-level Active Neutral Point Clamped (ANPC) inverter when its switches are submitted to open and short-circuit failures. The main change consists on adding a thyristor in parallel with each inverter switch. This improves the behavior of the converter when a switch fails. Fault detection and identification methods are presented together with configured schemes for ten types of failures. Simulation and experimental results validate the theoretical studies.