Diode-Based Fault Detection, Classification, and Localization Method for Photovoltaic Array

In this research work, a diode-based circuit and an algorithm are proposed to detect, classify, and localize faults in small- or medium-scale photovoltaic (PV) array with blocking diodes. Using a single voltage sensor for the whole PV array, the proposed method can detect line-to-line (L-L) and line-to-ground (L-G) faults and find the approximate number of faulty modules. In addition, the proposed circuit uses one voltage sensor to classify faults and one to detect the exact faulty string. Alongside, the proposed algorithm is capable of detecting low and high impedance faults. In contrast to complicated strategies, easy circuit analysis is done to examine the behavior of PV arrays in the event of faults. The proposed algorithm and circuit has been thoroughly tested through a hardware prototype.