Research On Control Method Of Optical Fiber-based Daylighting And Solar Tracking System

The development and utilization of solar energy can alleviate the global energy crisis and environmental crisis.As an important branch of solar energy application,the advantages of green environmental protection and human health which make solar daylighting system become one of the hot research spots.The real-time tracking accuracy and stability are the key factors affecting the daylighting efficiency and solar utilization efficiency.In order to improve the daylighting system efficiency,the solar tracking control method needs to be studied.Aiming at the small view angles range of tracking sensors cause the blind chasing and lost target,a dual-axis solar tracking system based on photoelectric tracking and solar trajectory is proposed to achieve large-range tracking.The tracking method based on the sun trajectory is constructed by the Wang Bingzhong trajectory(Wang)algorithm,tracking error of elevation and azimuth angle is ±0.5°.The TracePro software is used to analyze the relationship between the position of the focused spot and angle of incidence of solar rays,and the angular range satisfying daylighting efficiency is ±0.26°.And the photoelectric tracking with an accuracy of 0.05° is designed by the four-quadrant tracking principle.According to the tracking requirements of the daylighting system,the system is designed with STM32 and embedded operating system ?C/OS-II.The remote monitoring and control platform is built by C/S mode and WiFi communication.The experiment shows that the monitoring system can meet the requirements of real-time monitoring of tracking system parameters.The Wang algorithm combined with ADAMS/MATLAB to establish a simulation model and achieve a tracking device based on the way the sun trajectory.The simulation how that the system can quickly track the target angle,and real-time to reflect state of sun motion of the tracking system.In order to solve the problem of theoretical design value and the actual illumination error of the tracking sensor,a correction compensation strategy is proposed which used to correct the positional deviation of the focused spot.The daylighting system characteristics under different control parameters and correction compensation strategies are analyzed.The results show that the tracking process is the best when the error correction coefficients of elevation and azimuth are 1.6 and 2.5,which effectively reduces the light intensity oscillation during the tracking process.Under the condition of stable light intensity,the adjusting fluctuations of elevation and azimuth are reduced by 68% and 33% respectively.Under complex weather conditions,the stability and optical-fiber output illumination are better,tracking accuracy and daylighting efficiency are improved.The research of the tracking control system can effectively realize the high-precision daylighting efficiency,which has great practical engineering significance and application value for reducing the building energy consumption during the day and improving the quality of healthy living.