Saeedeh Ahmadi - Faculty of Engineering and TechnologyImam Khomeini International UniversityQazvin, Iran
Shirzad Abdi - ImenSazan Consultant EngineersTehran, Iran

To increase the efficiency of photovoltaic (PV)systems, maximum power point (MPP) tracking of the solararrays is needed. Solar arrays output power depends on the solarirradiance and temperature. Also the mismatch phenomenoncaused by partial shade will affect the output power of solarsystems and lead to the incorrect operation of conventional MPPtracker. Under partially shaded conditions, the solar arraypower–current (P-I) characteristic has multiple maximum. Thispaper presents a maximum power point tracking (MPPT) withparticle swarm optimization (PSO) method for PV systems underpartially shaded condition. The performance of the proposedmethod is compared with perturb and observe (P&O) andimproved P&O (IP&O) algorithms, especially, under partiallyshaded condition. Simulation results confirm that the proposedMPPT algorithm with high accuracy can track the peak powerpoint under different insolation, temperature and partiallyshaded conditions, and it has the best performance in comparisonwith two mentioned MPPT algorithms. Also under rapidlychanging atmospheric conditions, the P&O algorithm is diverged.

photovoltaic; maximum power point tracking;partial shading; particle swarm optimization