Study on the Characteristics of Photovoltaic Large Array Based on the Double Diode Model

Research on the mathematical model and output characteristics of a large photovoltaic array has important significance for optimal allocation and maximum power point tracking. Based on the double-diode model of photovoltaic cells, this paper deduced the mathematical model of a large photovoltaic array and made the improvement to the model and parameter optimization. According to the principle of the maximum power point matching, the large photovoltaic array MATLAB simulation mode of the improved double diode was established by use of the Newton - Ravson algorithm to determine the values of Rs and Rp. The model has the advantages of simple structure, fast operation, and the output characteristics for various light irradiation and temperature levels could be simulated exactly only by use of some parameters from photovoltaic cell production businesses. The output current data of PV module under different temperature and illumination were measured by experiment. Compared with the simulation model, it is concluded that the precision of the model in low light and high temperature condition is better than that of the single diode model, and can be applied to various types of large photovoltaic array..