Overview of fault detection approaches for grid connected photovoltaic inverters

Over the past few years, the power electronic converters have gained significant attraction among researchers, especially as an interface between distributed generation (DG) systems and the grid. Hence, it is imperative to establish a path for enhancing the operation of power electronic converters, and improve their reliability. Further, it is identified that for a solar photovoltaic (PV) inverter the power module construction intricacy and the complex operating conditions may degrade the reliability of these modules, affecting the functional efficiency of the overall grid-connected PV systems (GCPS). These constraints are considered to have a serious impact on the safety and failure cost especially associated with the grid-connected PV inverters (GCPIs). Therefore, it becomes crucial to have a clear understanding on the health monitoring strategies and reliability aspects corresponding to GCPIs. Consequently, it is also necessary to arrange all the information regarding major failure modes and categorize their root-cause analysis specific to GCPIs. In light of the above requirements, this paper contributes to the current research in making the GCPS more robust, efficient and reliable. The review identifies a comprehensive list of various failure modes in the inverter power modules and capacitors, and provides a broad view of their detection and localization approaches available in the literature.