Real-time Modeling of Photovoltaic Strings under Partial Shading Conditions

Partial shading is unavoidable in photovoltaic (PV) systems. However, there still lacks an abstract modeling and simulation for PV strings under partial shading conditions. This paper proposes a modified Tubo search algorithm to find the locations of turning points in current-voltage (I-V) curve. PV model parameters are then identified by a particle swarm optimization algorithm with the location and search history of turning points. The proposed model can effectively approximate the actual PV string. The feasibility and accuracy of the proposed method are verified through simulation and experimental results.