Читать книгу Smart Grids and Micro-Grids - Umashankar Subramaniam - Страница 13

The ampleness and non-polluting nature of power generation from solar photovoltaic (SPV) is used worldwide to meet the ever-increasing load demand.In order to operate SPV efficiently, an accurate modeling and control is required prior to the installation. Therefore, this chapter presents the Single Diode Model(SDM) of SPV module through which five parameters such as series resistance (R_se), shunt resistance (R_sh), diode ideality factor (A), light generated current (I_LG), diode reverse saturation current (I_sat) are determined for extracting the maximum power from PV panel. Initially, this work describes the mathematical model of SPV in terms of the above specified unknown parameters. Using these modeling equations, the parameters are determined under standard test condition (STC). The manipulated form of SPV modeling equations under dynamic environmental condition are portrayed which are used for determining the parameters of SDM. From these parameters, the voltage and current at maximum power point (MPP) are deduced under varying environmental conditions. This study presents the numerical iterative techniques like Gauss-Seidel (GS) and Newton Raphson (NR) approach to solve the non-linear transcendental equations describing the behavior of SPV. The effectiveness of the presented method is tested with various SPV modules such as KD245GX, U5-80, and Shell SP70. The comparative analysis of results obtained reveal that among the presented numerical techniques, the NR method is simple to use, reduces the computational cost and robust. Further, the accuracy of the presented NR method is validated with the results obtained from the experimental data under dynamic environmental conditions. The comparison of I-V and P-V characteristics of HST60FXXXP PV panel from experimental results and numerical analysis shows unnoticeable deviation between them. The predicted values of MPP voltage and current estimated from numerical techniques under dynamic environmental conditions are in good agreement with experimental results.

Keywords: Solar PV parameter estimation, single diode model, maximum power point, Newton-Raphson, Gauss-Seidel