一种基于功率闭环控制的改进全局MPPT方法

在部分阴影的条件下，光伏阵列的P-U特性曲线呈现多峰值。针对现有方法在多峰值情况下最大功率点追踪的速度和准确度的不足，提出了一种基于功率闭环控制的改进方法。该方法首先采用功率闭环控制确定最大功率点所在电压范围，其次通过分析粒子群法和0.8倍开路电压法，选取适合算法对该电压范围进行精确的追踪。最后以两种典型的阴影条件为例，对现有的基于功率闭环的方法和所提方法进行对比仿真。结果证明了两种方法均能精确地追踪最大功率点，所提方法在追踪速度上有显著提升。

An improved global MPPT method based on power closed-loop control

Under partially shaded condition, the P-U characteristic curve of PV array shows the multi-peak value. In view of existing methods being lacking in speed and precision in the case of multi-peak maximum power point tracking, this paper puts forward an improved method based on power closed-loop control. Firstly, this method adopts power closed-loop control to determine the maximum power point voltage range. Then by analyzing the particle swarm method and 80% of open-circuit voltage algorithm, this method selects suitable algorithm for accurately tracking the voltage range. Finally, by taking two typical shadow conditions for example, this paper takes the existing method based on power closed-loop and the proposed method to make compared simulation. The final results show that the two methods can accurately track the maximum power point and the proposed method has significant improvement on the tracking speed. This work is supported by National Natural Science Foundation of China (No. 61662044), Natural Science Foundation of Jiangxi Province (No. 20132BAB211039), and Science and Technology Support Plan of Jiangxi Province (No. 20142BBE50037 and No. 20151BBE50050).