Study of Inverter Open-Circuit Fault in Grid Connected Photovoltaic Systems: Influence on Output Power and Detection Method.

The paper presents an investigation of single switch open-circuit fault in the inverter of photovoltaic (PV) systems. An IGBT two-level three-phase inverter which is used to connect the photovoltaic system to the main grid is considered in this application. First, the fault is created by modifying the control gate signal sent to the inverter. Second, the operation of a PV system is simulated under various levels of the irradiation under both healthy state and the condition of single switch open-circuit fault. The output powers generated by the system are then compared to show the influence of fault occurrence. Based on the DC current of the inverter, fault detection method is recommended. Investigation results show that the fault strongly affects the output power and that can be detected by judging the amplitude of three first orders of the AC side fundamental frequency. [ABSTRACT FROM AUTHOR]