基于β参数的光伏系统最大功率点跟踪算法研究

MAXIMUM POWER POINT TRACKING ALGORITHM OF PHOTOVOLTAIC SYSTEM BASED ON β-PARAMETER

针对扰动观察法在最大功率点(maximum power point,MPP)附近存在振荡、跟踪步长与跟踪精度无法兼顾等问题,提出一种基于β参数的最大功率点跟踪算法,通过分析β-U曲线,在跟踪过程中分别采用变步长占空比扰动法和模糊控制法,进而提高系统跟踪速度和稳态精度。为了验证该方法的有效性,在Matlab平台对光伏系统最大功率点跟踪的稳态和动态性能进行仿真,并用"可编程直流电源"来近似模拟光伏系统进行实验研究,仿真和实验结果表明所提出的方法具有较高的稳定性能和良好的动态性能,能有效提高系统跟踪速度和控制精度,实现最大功率点跟踪。

Maximum power point tracking is one of the key techniques in photovoltaic power generation systems.To reduce oscillation at maximum power points(MPP)and to make tracking step size and tracking accuracy compatible,βparameter is proposed to track the MPP of photovoltaic system in this paper.By analyzing theβ-U curve,the tracking process is divided into two phases with the value ofβ.At different phases,the variable step duty cycle disturbance method and the fuzzy control method are used to track the MPP which can further improve the system optimization efficiency and the tracking speed.In order to justify the effectiveness of this method,the static and dynamic properties of the maximum power point tracking of photovoltaic system is simulated using the Matlab simulation software,and the experiments are conducted by using a"programmable DC power"to roughly simulate the photovoltaic systems.The results show that this method exhibits satisfactory static property and excellent dynamic performance,and can effectively improvethe tracking speed and control accuracy of the system,thus achieving successful tracking of MPP.