Development a new algorithm for maximum power point tracking of partially shaded photovoltaic arrays

The photovoltaic (PV) arrays exhibit a nonlinear P-V characteristic and its maximum power point (MPP) varies with solar insolation. Often, the PV arrays get shadowed completely or partially, in which the P-V characteristic get more complex with multi-local MPPs. In this condition most of former methods fails to get global MP. This paper presents a new algorithm to track global MPP under partially shaded condition. The algorithm acts by a heuristic search of array voltage to find global MPP. In the process of heuristic search, reference voltage of PV output is generated and used for perturbation. After each perturbing, results are used for better search, until achieving the convergence constraint. To check the accuracy and precision of the method an accurate model of PV array was implemented in MATLAB software and various tests were conducted.