基于光伏阵列输出特性的GMPPT算法研究

针对局部阴影条件下光伏阵列的P-V曲线呈现多峰值的情况,在研究光伏阵列输出特性的基础上提出了一种全局最大功率点追踪GMPPT(global maximum power point tracking)算法。该算法由均匀光照和局部阴影条件下的两个最大功率点追踪算法构成。通过所提出的局部阴影检测手段判别光伏阵列所处的光照条件,从而决定使用哪个子算法。最后将该算法在Matlab中进行仿真验证。仿真结果表明在局部阴影条件下该算法能快速地追踪到全局最大功率点,且避免了对整条P-V曲线的扫描。在均匀光照条件下要比传统的最大功率点追踪算法(扰动观察法)更快地定位到最大功率点。

Research on GMPPT Algorithm Based on Output Characteristics of Photovoltaic Array

In consideration of the multiple peaks appearing on the P-V curves of photovoltaic(PV) array under local shading conditions, a global maximum power point tracking(GMPPT) algorithm is proposed based on the output characteristics of PV array. This algorithm is composed of two maximum power point tracking algorithms, which are under uniform illumination and local shading conditions, respectively. By means of the proposed local shadow detection method, the illumination condition for the PV array is distinguished to determine which sub-algorithm will be adopted. Finally, this algorithm is verified through simulations using Matlab, showing that it can fast track the global maximum power point under local shading conditions and avoid scanning the whole P-V curve; under uniform illumination conditions, it can locate the maximum power point faster than the traditional maximum power point tracking algorithm(e.g., perturbati-on and observation method P&O).