The Design Of Photovoltaic Plate Automatic Light Tracking System

Under the dual pressure of the energy crisis and the deterioration of the ecological environment,for the development of economy and the progress of civilization,human beings are eager to find a new type of clean and renewable energy.Because of its wide range of advantages,solar energy has become one of the most promising in terms of many of its goals.The utility model has the advantages of large reserves,wide coverage,no need of exploitation and transportation,no toxicity,no pollution and no carbon emission.One of the important ways of using solar energy is photovoltaic power generation,but due to high cost and low efficiency of electricity generation,is susceptible to environmental impact of climate and other shortcomings,which seriously restrict the development of photovoltaic power generation,photovoltaic plate with automatic therefore explore the necessary optical device.This paper first analyzes the photoelectric conversion principle,the external characteristic equivalent circuit,the influence factors of the photoelectric conversion efficiency and so on,the solar radiation intensity and the output load power showed positive correlation,to lay the foundation for further design.The system is designed for small distributed power generation system tracking system,so the selection of low energy consumption,high life of single axis tracking.As the weather is unpredictable,this paper selects two complementary tracking methods of the photoelectric tracking and visual daily tracking,this system is designed for sunny,cloudy,windy day in different tracking mode,according to different weather conditions,the device can choose the corresponding tracking mode.According to the function of the system,this paper designs the overall scheme of the system,and then designs the hardware and software separately.The hardware has the following modules:mechanical tracking mechanism,tracking sensor,wind speed protection,digital to analog conversion module FX2N-4AD,PLC programmable controller,man-machine interface and so on.The software contains the flow chart and the PLC program design,the idea of tracking is introduced,mainly including the solar automatic tracking,photoelectric tracking,visual tracking three flow chart;at the same time the sun automatic tracking program,part of the manual mode tracking program,determine the specific design of cloudy part of the program,photoelectric tracking part of the program and describes the corresponding functions,realizes the automatic tracking mode and manual mode combination.At the same time,the man-machine interface of touch screen is added to control and monitor the whole system more conveniently and intuitively.Finally,the hardware and software programs are debugged by simulation software.The 3 modes of the moving light are used to simulate the motion of the sun.Then,through the comparison of the experimental data of the real time output power of the photovoltaic plate placed in overcast and sunny angle,it is proved that the system can realize stable and reliable tracking.In this paper,the design of the photovoltaic plate with the light system can automatatacally track the motion of the sun's objects,so that the light can be shot as perpendicular as possible to the photovoltaic plate,and improve the efficiency of photoelectric conversion,thereby increasing the amout of power generation.