Pole voltage based-approach for IGBTs open-circuit fault detection and diagnosis in PWM-VSI-Fed induction motor drives

This paper describes an investigation of insulated-gate bipolar transistors (IGBTs) open circuit faults detection and diagnosis in voltage source inverter (VSI) fed induction motors. The proposed strategy is based on the combining of the inverter pole voltage measurement and the switching pattern. The combined diagnosis signals allow not only the detection of single fault but also the multiple open circuit fault of the inverter switches. For simplicity and cost-effectiveness, the fault detection for each inverter leg is carried out by a simple circuit. To avoid the false diagnosis alarms, the time delays due to turn-on and turn-off process of the power switches are compensated while acting on the switching pattern. Different from the conventional method, the proposed technique was marked by a better time delay between the fault occurrence and its detection. The Simulation and experimental results are displayed to confirm the proposal.