Methodology of fault diagnosis for grid-connected photovoltaic systems of network connection

The aim of the present research work is the design of a methodology of fault diagnosis as a contribution to the improvement of indicators about efficiency, maintenance and availability of Photovoltaic Systems of Network Connection (PVSNC). The network connection inverter and the mathematical model of the Photovoltaic Generator were firstly analyzed. Afterwards, the existing operational losses of the Photovoltaic Generator were quantified, and the mathematical model was adapted to the real conditions of the System through a polynomial adjustment. A real network connection system of nominal power 7.5 kWp installed at the Research Center of Solar Energy, in the province of Santiago de Cuba, was used to assess the proposed methodology. The results obtained were validated to show that the proposed design successfully supervises the PVSNC. 100% of the simulated faults were detected and identified with the designed methodology, whose usefulness was additionally shown when having a maximum rate of 0.22% of false alarm in all the tests done.