The maximum power tracking of variable step fuzzy logic control based on power prediction

Abstract

The perturb and observe algorithm oscillates in the vicinity of maximum power point, and fixed step size can not be set on the premise of meeting tracking accuracy and speed. To locate the optimal operating point of photovoltaic power generation system and to solve the contradiction between tracking accuracy and speed, a variable step fuzzy logic control method based on power prediction is proposed. In other words, the variable step is introduced on the basis of power prediction method and meanwhile, the fuzzy logic control method is adopted control the variable step in real time to track the maximum power point. The comparison of simulation results of other methods and that of the method proposed in this paper shows that the method proposed cannot only track the maximum power point fastly, but also improve the dynamic performance and steady-state performance of the system. The experimental results prove the effectiveness and practicability of the algorithm.