Study On Theory And Method Of Improving Efficiency Of PV Array

Solar photovoltaic power generation system is vulnerable to clouds,buildings,trees,poles and towers and other fixed or non-fixed objects,resulting in local shadows,resulting in hot spot effect,has become the main factor affecting photovoltaic power generation.To solve this problem,the following work is done to improve the output efficiency of photovoltaic array under the influence of shading.The main work is as follows:(1)Aiming at the problem that solar photovoltaic power generation system is vulnerable to local occlusion,which leads to the decrease of output power and the damage of equipment,this paper proposes a physical connection method combining the topological structure of reticulated photovoltaic arrays and optimizing physical connection,which effectively disperses the local shadows to the whole photovoltaic arrays without reducing them by studying the theoretical principle of Sudoku mathematical model.Shadow occlusion area is reduced,but the influence of shadow occlusion is dispersed to the whole array to reduce mismatch loss.The optimization structure is studied by MATLAB simulation.The results show that the proposed method can effectively improve the output characteristics of photovoltaic arrays.The effectiveness and applicability of the proposed method are verified by different shading modes.(2)Based on the traditional PSO algorithm,an adaptive particle swarm optimization(APSO)algorithm is proposed to study the global MPP tracking control strategy.This method can dynamically adjust the parameters of PSO according to the array voltage information obtained during the iteration process of the algorithm,enhance the particle optimization speed and improve the convergence speed of the algorithm.At the same time,the algorithm start strategy,particle initial location decentralization strategy and effective iterative termination strategy are proposed to avoid the oscillation at the optimal point.Finally,simulation results show that the method can track the global optimal MPP quickly and accurately with or without shadows or photovoltaic module faults.It has good convergence and optimization ability,effectively improves the output power of photovoltaic array under local occlusion,and has good practical value.(3)Aiming at the proposed maximum power point tracking algorithm under partial occlusion of photovoltaic arrays,a certain scale simulation model of photovoltaic arrays is built,and the proposed control method is analyzed and compared under the simulation environment and the test platform.The results show that the proposed method has excellent performance in experiments.Compared with the traditional maximum power point algorithm,the proposedadaptive particle swarm optimization algorithm has more obvious advantages,better adaptability to environmental changes,faster response speed and higher accuracy,and has the advantages of smaller power oscillation amplitude and better robustness at the global maximum power point.