用于农业大棚的光伏阵列最大功率点跟踪算法研究

Abstract

In order to enhance the utilization of solar energy in photovoltaic greenhouse, this paper takes the optimization strategy of photovoltaic array's maximum power point tracking algorithm as research object. According to the changing rule of the slope of photovoltaic array's output P-U curve, this paper proposes a new variable-step conductance increment method to track the maximum power point. When the working point is located on the left side of maximum power point, the logarithmic function value of curve’s slope is adopted as the voltage step to adjust the position of working point. When the working point is located on the right side of maximum power point, the exponential function value of curve’s slope is adopted as the voltage step to adjust the position of working point. Through the MPPT modelling and simulation in MATLAB/Simulink and the corresponding circuit test, the result shows that comparing with the traditional variable-step conductance increment method, the proposed algorithm can find the maximum power point faster, and it can effectively reduce the power loss caused by step oscillation in the searching process, which achieves the goal of enhancing conversion efficiency of photovoltaic power generation.