Design Of Photovoltaic Automatic Tracking System

The solar energy has an enormous developing application capacity as one kind of green renewable energy source which can be continuously used forever. But there is tremendous relationship between photovoltaic cells output characteristics and the change of external environmental factors, currently the efficiency of PV cells is not only low but also expensive on a large scale of production. The photovoltaic automatically tracking device can raise the solar energy utilization rate and bring down the cost of the solar electrical energy generation. Precise solar tracking mechanism can make solar panel receive more radiant energy and increase generating capacity. This paper makes use of cheap photo sensors and MCU circuit to realize the function of sun tracking.Simulation was used to draw the outputting characteristics of photovoltaic cells in accordance with the principle of photovoltaic power generation in the paper. Compared several typical condensers and selected the right type of condenser, the author explored the design method at the basis of the analysis of several typical condenser principles. Analyzed the law of the sun, compared the current tracking methods, and improved the previous tracking mode. Proposed electro-optical tracking as the major tracking mode while the sun trajectory tracking mode as additional tracking mode on unusual weather conditions. Through two complementary tracking modes, on the one hand, electro-optical tracking can give full play to the advantages of high accuracy; on the other hand, the system can still achieve tracking on cloudy weather conditions. In addition, In order to guarantee that the track result is accurate, after azimuth and elevation angle adjustment, increased a group of sensor electric circuit to carry on the track result confirmation.Through the implementation of functional analysis of control system, the thesis completed hardware and software design of the tracking device. Include: MCU interface circuit design, optical detector circuit design, control and implementation component design and the software design of electro-optical tracking and sun trajectory tracking module. The tracking system test equipment manufacture is completed. The experimental results showed that, the system could fully realize the tracking of the sun. Finally, proposed improvement program and new method to treat fast cloud according to the tracking effect of the trial.In this paper, the designs of photovoltaic automatic tracking device have simple structure, low cost and stable operation. The device can be widely applied to grid and off-grid PV power system.