基于局部阴影下光伏阵列电流特性的最大功率点跟踪算法

光伏发电作为目前太阳能利用的主要形式,容易受到局部阴影的影响,其P-V输出特性曲线呈现多峰特点,使得常规的最大功率点跟踪方法难以准确跟踪到全局最大功率点。通过充分利用局部阴影下光伏阵列最大功率点电流与短路电流之间近似的比例关系,提出一种三步骤全局最大功率点跟踪算法,该算法能够快速准确地跟踪到系统全局最大功率点,且不需要任何附加硬件电路。以1k W的Boost变换器为实验平台,将所提出算法和常规全局搜索法的跟踪过程进行比较,证明了该算法的有效性。

Maximum Power Point Tracking Algorithm for Photovoltaic Array under Partial Shading Based on Current Property

As one of main forms of solar energy utilization, photovoltaic array is vulnerable to the shadow effect, thus itsP-V output characteristic curve contains more than one peak. As a result, it is difficult for the conventional algorithms of maximum power point tracking (MPPT) to track the global maximum power point. Based on the approximate proportional relationship between the photovoltaic (PV) array maximum power point current and short circuit current, a novel algorithm is proposed in this paper. The proposed algorithm can guarantee the tracking speed as well as accuracy without any additional circuits. Tracking performance of the proposed MPPT method and global search method was compared based on a 1kW rated boost converter. The experimental results indicate that the proposed MPPT algorithm is effective.