Research On Multi-parameter Optimization Design Of Bracket Beam Structure Of Photovoltaic Tracking System And Wind Shelter Control Strategy

With the consumption of non-renewable resources,it is an important direction of future energy development to deal with energy problems and develop new energy to change the world energy structure.With the characteristics of clean,pollution-free,large size and wide distribution,solar energy has attracted the attention of countries all over the world,which makes photovoltaic technology develop rapidly in recent years.Photovoltaic tracking technology can improve the efficiency of photovoltaic power generation and has become one of the representative technologies developing rapidly in recent years.Because photovoltaic power generation needs to work in a wide outdoor area for a long time,it is easy to be disturbed by external wind load.It is of great significance to study the structure and control strategy of photovoltaic tracking support and improve the reliability and service life of photovoltaic tracking system.The main research contents are as follows:The influence of wind direction Angle and working condition Angle on the wind pressure distribution of photovoltaic module surface was explored,and the specific values of body type coefficients of different distribution models were given.The wind pressure distribution on the upper and lower surfaces of photovoltaic modules under different wind angles was simulated by CFD simulation.The influence of wind direction Angle and working condition Angle on wind pressure distribution on photovoltaic module surface was analyzed.Considering the effect of bending moment on photovoltaic support,a four-quadrant wind load model was proposed.The model of uniform distribution,trapezoidal distribution and four-quadrant distribution is compared,and the corresponding size coefficient is given.Based on NSGA-II algorithm,the multi-parameter optimization of photovoltaic tracking support beam structure is carried out,and the effectiveness of the optimization results is verified by experiments.According to the model of wind pressure distribution and shape coefficient of photovoltaic modules,wind load is taken as the boundary condition of photovoltaic tracking support structure.The response surface model of maximum stress and maximum displacement of photovoltaic tracking support structure was established,and the influence of different parameters on the load resistance of photovoltaic tracking support structure was analyzed.Based on NSGA-II algorithm,the multi-parameter optimization of the main and secondary beam structure of photovoltaic tracking support was carried out,and the optimal parameters of the main and secondary beam structure were determined,and the error analysis of the optimal structural parameters was carried out to check its stability.Finally,the photovoltaic tracking bracket structure is simplified,and the object is processed according to the optimization results.The equivalent static load test of photovoltaic tracking support structure is carried out,and the experimental results meet the requirements of bearing capacity.The effectiveness of the simulation optimization results is verified.The load resistance of the photovoltaic tracking bracket structure is improved,and the material cost per unit area is reduced by 11.58 %.The trajectory model of apparent solar motion was established.Analyzed the movement of the sun throughout the year.The effectiveness of the apparent solar trajectory model is verified by experiments.And the risk-avoidance control system under different wind speed levels of photovoltaic tracking system is realized.Taking Ningbo area as an example,the mathematical model of apparent solar motion trajectory is established according to astronomical calculation.The trajectory of the sun’s position over time.The variation of the position of the sun in four seasons in Ningbo is analyzed.According to the trajectory of the sun,the operation control mode of the photovoltaic tracking bracket is given.The effectiveness of the apparent solar trajectory model is verified by comparison of energy generation.The photovoltaic tracking risk-avoidance control strategy under extreme wind load is studied.Equivalent static load force analysis and modal analysis of photovoltaic tracking support structure were carried out.The structural characteristics of photovoltaic tracking support at different wind speed levels were studied.Considering the force and natural frequency of photovoltaic tracking support structure at different working angles under different wind speed levels,the wind shelter conditions of photovoltaic system under different wind speed levels were determined.It not only ensures the efficiency of photovoltaic power generation,but also has reliable wind shelter performance.Combined with the wind speed sensor,it realizes the risk avoidance control system under extreme wind load.