光伏发电中基于模糊自适应修正变步长最大功率点跟踪的控制策略

Modified Type of Variable Step Size Maximum Power Point Tracking Control Strategy Based on Fuzzy Adaptive for Photovoltaic Arrays in Photovoltaic Power Generation

最大功率点跟踪能够有效快速地实现光伏阵列的最大功率输出,提高光能转化效率。针对传统变步长导纳增量法在光伏阵列中最大功率点寻优时步长和阈值选择上的困难,导致其动态响应速度和输出功率波动性以及跟踪精度的缺陷,提出了一种新型变步长控制参数的修正方案,利用模糊规则语言实时调整变换器的功率占空比;并分析了光伏电池的工作特性,建立其连续导电模式的小信号状态空间模型并验证其稳定性。最后,通过MATLAB/Simulink对比了与传统定、变步长导纳增量法的仿真验证。试验表明:模糊自适应修正控制算法有效提高了系统的动态响应特性、缩短了寻优时间,并具有较高的稳态精度。

The maximum power point tracking（MPPT） can effectively and quickly realize the maximum power output of the photovoltaie array, and improve the efficiency of light energy conversion. A novel variable step size control parameter correction scheme was proposed according to the traditional variable step size incremental conductance algorithm in photovoltaic system maximum power point tracking when the step size and threshold selection difficult, resulting in the dynamic response speed and output power fluctuation and tracking accuracy of the defects. By using fuzzy language rules, the power duty of the converter was adjusted in real time and the working characteristics of the photovoltaic cells were analyzed. The small signal state space model of the continuous conduction mode was established and its stability was verified. Finally, by comparing with the traditional fixed step and variable step incremental conductance method through the MATLAB/Simulink simulation, experiments showed that the fuzzy adaptive control algorithm could effectively improve the dynamic response characteristics of the system, shorten the search time and had a higher steady-state precision.