A Novel Active Shadow-Based Fault Detection and Localization Method for Photovoltaic Systems

Fault detection in photovoltaic (PV) systems is crucial for operation safety. However, traditional methods often struggle with accurately identifying and locating faults under normal operation and require complex sensor setups. To enhance the efficiency and accuracy of fault detection and localization, this study proposes an active shadow (AS)-based fault detection method for PV systems. By introducing an active shading device to the PV modules and applying shadows in a specific sequence, the method analyzes changes in array output power to accurately detect and locate faults, enabling rapid fault detection without disrupting normal operation. Through introducing a multi-level high-precision simulation model based on the series substrings and defining an identification coefficient (IC) to evaluate the algorithm's performance, this method is proved to locate faults across various PV array sizes under complex partial shading (with varying shadow areas, positions and intensities), as well as short-circuit and open-circuit faults. Real-world PV array experiments further confirm the method's feasibility and robustness.