Abstract: In order to solve the problems of misjudgment, oscillation and tracking velocity of traditional perturbation observation method, a control strategy based on power prediction variable step size perturbation observation method is proposed. When the sampling frequency is fixed and the light intensity remains constant and the temperature changes, the output power of the photovoltaic cell can be approximately linear in unit time. The rapidness of the traditional perturbation observation method with large step size is used to track the maximum power point, and then the linear power prediction is carried out near the maximum power point, so as to accurately track the maximum power point. A simulation model is built in the simulation platform, and the results show that the new control strategy improves the tracking speed and accuracy of the system, and optimizes the output performance of the system.

Key words: photovoltaic characteristics, maximum power tracking, power prediction, perturbation observation method