由于光伏电池的输出特性会随着环境变化而改变, 因此, 合理的最大功率点跟踪 (maximum power point tracking, MPPT) 技术是提高光伏发电系统效率的关键. 但在定步长算法中, 跟踪速度和稳态精度之间存在固有矛盾, 而传统变步长算法在光照变化下缺乏灵活性, 起动速度慢, 制约了 MPPT 的跟踪质量. 针对此问题, 提出一种优化的变步长电导增量法. 该算法可根据工作点位置选取合理的跟踪比例系数, 克服了传统变步长算法动态响应速度慢、精度不高的问题. 在 Matlab/Simulink 下的仿真结果证实了该算法在变化的光照情况下的可行性.

As output characteristics of photovoltaic cells change with the change of environment, reasonable maximum power point tracking (MPPT) is a key in improving efficiency of a photovoltaic system. However, there is an inherent contradiction between tracking speed and steady-state accuracy in a fixed step algorithm. The traditional variable step algorithm lacks flexibility, and has a slow start speed, limiting tracking quality of MPPT. An improved variable step incremental conductance method is proposed to solve this problem. The algorithm can select a reasonable proportion coefficient for tracking according to different work locations to overcome problems in the traditional variable step size algorithm. Simulation with Matlab/Simulink shows feasibility of the algorithm under varying illumination conditions.