Three-level NPC inverter fault diagnosis by the Average Current Park's Vector approach

Abstract

This paper presents a diagnosis method for the detection and location of open-circuit faults in 3-Level NPC inverters with SVPWM modulation scheme based on even-order harmonic elimination. The performance of the NPC inverter under normal and faulty conditions is firstly investigated both by simulation and experiments. Afterwards, a method for inverter diagnosis is proposed, based on the Average Current Park's Vector. This method proved to be capable of detecting and locating the phase and the semiconductor pair where the faulty IGBT is located.