Fault Detection and Diagnosis of Photovoltaic Systems through I-V Curve Analysis

Abstract

This work presents an algorithm to detect and diagnose faults in PhotoVoltaic (PV) systems based on the I-V curve analysis. Three types of faults are investigated: mismatch and shading faults, connectivity faults and short circuit faults. The PV system is modeled using MATLAB/Simulink to simulate the faulty I-V curve behavior for each fault. During each simulation, the I-V curve is examined and compared with that during normal operation (without faults), in order to identify and characterize the anomalies. The different faulty modes affect the I-V characteristics of the PV string in different ways, leaving distinct signatures during its operation. Four attributes are extracted allowing for classification of faults into five classes. For some classes involving more than one fault, further analysis and comparison is carried out to allow discrimination between them. Results show that the proposed technique has good performance in detecting faults even if they are not severe.