一种光伏电池动态模型的参数提取方法

文中研究了光伏电池的动态特性、动态模型及其参数提取问题.提出了光照下光伏电池输出阻抗频率特性的隔离电容测试法,分析了光照情况下的小信号频率特征.建立了光伏电池动态模型以及小信号阻抗模型.基于光伏电池的实验测试数据,提出了一种结合阻抗频率特性、光伏数学解析模型和非线性拟合迭代算法的动态模型参数提取方法.该方法通过先提取固定的、耦合性较低的参数,再提取耦合性强的、随环境变化的参数,极大降低参数提取的难度.通过对比模型仿真与实验结果,验证了参数提取方法的正确性、有效性.

Parameter extraction method of photovoltaic cell dynamic model

This paper investigates the dynamic characteristic, dynamic model and parameter extraction of photovoltaic (PV) cells. Firstly, the isolated capacitance method is presented to test the output impedance frequency characteristics of PV cells under illumination, and then the small-signal frequency characteristics under illumination are analyzed. Then, the dynamic model of PV modules and the small-signal impedance model are built. Based on testing data of PV modules, a model parameter extraction method combining impedance frequency characteristics, PV mathematical analytical model and nonlinear fitting iterative algorithm is presented. This extraction method firstly extracts those fixed parameters with low coupling, and then extracts the parameters with strong coupling and changing with the environment, which greatly reduces the difficulty of parameter extraction. At last, correctness and effectiveness of the proposed extraction method for model parameters are verified by comparing the simulation and experimental results.