Influences of power electronic converters on current-voltage behaviors during faults in DGUs-Part II: Photovoltaic systems

Photovoltaic (PV) systems have become a popular type of distributed generation units (DGUs) for small and medium levels of renewable energy generation. These DGUs are designed and operated to deliver electric power through one or more stages of power electronic converters (PECs). The non-linear and switched natures, along with control actions, of PECs used in PV systems can be of major influences on current-voltage behaviors during faults. Such faults may take place on the PV system side or host grid side. This paper investigates the current-voltage behaviors in grid-connected PV systems during fault conditions.