Research On Solar Photovoltaic Power Generation PSD Tracking Technology

Solar energy is viewed as an ideal renewable green energy,viewed from the energy security and energy strategy point.Solar power generation is an important way to solve the shortage of fossil energy and reduce environmental pollution.Solar photovoltaic power generation is a direct way to convert solar energy into electricity through photovoltaic cells.It is the two main problems to improve the utilization of solar energy and reduce the cost of power system in the field of solar energy application.Based on the problems of the sun tracking,this paper mainly includes the following aspects to research photovoltaic power generation tracking technology:1.Research on the overall scheme of PSD tracking technology.Analyzed photovoltaic power generation system,sun tracking method,the main components of the system,presented a research project of solar photovoltaic power generation tracking technology based on position sensitive device(PSD).2.An improved conjugate gradient algorithm is presented to modify the nonlinearity of PSD.Analyzed the nonlinear characteristics of PSD and the adverse effects on measurement results,presented an improved conjugate gradient algorithm.The algorithm makes use of the gradient of the objective function,to produce the conjugate direction and search the minimum point of the function through change the step length,so as to make the nonlinear correction of PSD.An example is given to verify the feasibility of the algorithm through MATLAB/Simulink simulation.3.The photovoltaic solar tracking method based on PSD is studied.A solar photovoltaic power generation PSD tracking method is proposed based on the analysis and compare of the tracking modes of a variety of photovoltaic power generation system.The method makes use of the advantages of PSD to measure the position of the incident light on the photosensitive surface accurately,improves the tracking accuracy of the photovoltaic power generation automatic tracking system effectively.4.Design of PSD tracking hardware circuit for solar photovoltaic power generation.The solar photovoltaic power generation PSD tracking hardware circuit is designed using AT89C51 as the main controller.Including signal acquisition circuit,horizontal and vertical direction detection circuit,the interface circuit of AT89C51 and optocoupler PC847,stepper motor drive circuit,the interface circuit of stepper motor driver chip L297/L293 D and PC847 are designed.5.Design of PSD tracking software for solar photovoltaic power generation.Compiled the software of each module according to the modular programming idea.Including the main program of solar photovoltaic power generation PSD tracking,PSD tracking module,solar motion trajectory tracking module,stepper motor drive module.6.The construction of solar photovoltaic power generation PSD tracking technology experimental platform.The experimental data of solar photovoltaic system before and after using PSD tracking method are measured.Analyzed the open circuit voltage,short circuit and output power.The superiority of the technology is verified.From the methods and conclusions obtained by solar photovoltaic power generationPSD tracking technology,it is proved that this technology can improve the utilization rateof solar photovoltaic power generation system effectively,can provide power outputstably,to ensure the normal operation of electricity load.