Photovoltaic Array Maximum Power Point Tracking Based on Improved Perturbation and Observation Method

Abstract

The output characteristics of photovoltaic cells are strong non-linearity, and maximum power point tracking technology can improve the efficiency of photovoltaic systems. Based on improved perturbation and observation method, this paper takes the advantages of both long and small steps to realize the maximum power tracking of the photovoltaic system. Firstly, the absolute value of the real-time power rate of change is used as a reference for the automatic variable step size, and the maximum power is quickly tracked with a large step when the external conditions change. Then, after reaching the maximum power point, the system automatically becomes a small step to reduce the power oscillation loss. Finally, average calculation module is added to the power sampling to reduce the impact of clutter on the system and prevent the “sharp peak” of power. The results of the maximum power point tracking example show that the model has significantly improved the tracking speed of the maximum power point and the range of oscillation near the maximum power point.