An effective method for detection and location estimation of faults in large-scale solar PV arrays

The prolonged undetected electrical faults in large-scale solar photovoltaic (PV) arrays are the main cause of fire hazards. In this paper, an effective method is proposed for detecting and locating faults in such large-scale PV arrays using cumulative sum of the changes in the string currents. The efficacy of the approach is evaluated on different electrical faults simulated on a 3 MW grid-connected solar PV plant through MATLAB/Simulink under varying system operating conditions. The findings clearly show that using this technique even critical faults such as high resistance ground faults, low mismatch faults and simultaneous faults in PV arrays can be detected and located within 5 ms. The comparative assessment results also justify the superiority of the proposed method over the available schemes.