Research On Optimal Design Method Of Building Photovoltaic Power Generation System

With the proposal of carbon peaking and carbon neutralization,photovoltaic power generation,as the main form of solar energy resource utilization,has great development potential,and puts forward higher requirements for the efficiency of photovoltaic power generation.When the photovoltaic system is affected by local shadow occlusion,different light receiving angles and other factors,the uneven light intensity received by the photovoltaic array will significantly reduce the power generation efficiency.In order to improve the efficiency of photovoltaic array under uneven light receiving conditions,this thesis focuses on the optimization of photovoltaic array under uneven light receiving conditions,focusing on the optimal layout of photovoltaic array in limited space,the analysis of mathematical model and electrical output characteristics of photovoltaic array under uneven light receiving conditions,and the selection and optimization of optimal topology of photovoltaic array under uneven light receiving conditions.The main work contents and research results are as follows:（1）The layout optimization of photovoltaic array considering shielding in limited space is studied,the mathematical model of the optimal spacing of photovoltaic array in the form of support is established,and the photovoltaic system of a railway station building in a city is designed.The optimal layout scheme of photovoltaic array is selected by analyzing and comparing the power generation prediction and loss prediction of roof mounting and traditional support installation schemes.（2）Based on the electrical output characteristic model of photovoltaic cells under uniform illumination,the mathematical model of electrical output characteristics of series photovoltaic array under uneven light receiving conditions is established,and the electrical output characteristics of photovoltaic array under uneven light receiving conditions are simulated and analyzed.The conclusion that the output power of photovoltaic array is seriously reduced under uneven light receiving conditions is obtained,and the multi peak characteristics of P-V output characteristic curve are obtained.（3）The mathematical models of five photovoltaic array topology configurations are established,and the electrical output characteristic curves of five photovoltaic array topology configurations are compared and analyzed under a variety of typical uneven light receiving conditions.Finally,it is concluded that the total cross tied（TCT）photovoltaic array configuration has the best performance under uneven light receiving conditions.（4）In order to further improve the output power of TCT photovoltaic array under uneven light receiving conditions,a new discretization method is proposed based on the traditional cross connection to optimize the TCT photovoltaic array.The simulation results show that this method can significantly improve the power generation efficiency of TCT photovoltaic array under a variety of shadow,occlusion and other uneven light receiving conditions.