Research On The Auto-tracking System Of The Dish-stirling Thermosolar Power Generation Device

Today, Chinese environmental pollution problem becomes more and more serious, the main way to achieve electricity is still through thermal power from fossil fuel which inherently related with acid rain and dust-haze lead to the concern of public. As the typical representative of clean energy, therefore, solar energy has a bright prospect. For now, the main techniques of utilizing solar energy in our country to generate electricity is the photovoltaic power generation and the thermosolar power generation. Solar tracking system is an important part of thermosolar power generation system, the stability and tracking accuracy of it can effect on the utilization ratio of solar power, generating efficiency and cost. The objective of this paper is to design a solar auto-tracking system which can be used to drive the 25 kW Dish-stirling thermosolar power generation system. To realize the solar tracking system, lots of theoretical analysis has been done and both hardware and software of the solar tracking system are designed in this paper. Finally, the solar tracking system designed in this paper is tested on a 25 kW Dish-stirling thermosolar power generation system. The results show that the functions of the solar tracking system design in this paper are realized.The main research work in this paper includes:(1) Analysis of the current research status and development trend of solar tracking system for thermosolar power generation device in both China and abroad, and discuss the important meaning of it. Based on the problem of solar tracking system designed in China, the research objective and contents of this paper are proposed.(2) According the theoretical research of two common tracking strategy called sun trajectory tracking and closed loop tracking, and combine with the practical application, the control strategy of solar tracking system designed in this paper is determined that utilize both sun trajectory tracking and closed loop tracking method.(3) Based on the real function requirements, a control algorithm is proposed that utilize the Jean Meeus algorithm based sun trajectory tracking as the main control strategy and the deviation can be modified by the closed-loop feedback signal, due to which a PC-based software is designed for controlling. In order to solve the problem of instability and low response speed, the PI control algorithm is utilized during design two tracking mode.(4) A hardware system is proposed which are used as test platform for verifying the control algorithm. Combined with the software, the function and design mentality of modules in hardware system are introduced by steps.(5) After the simulation and debug on hardware test platform, the solar tracking system designed in this paper is tested on a real 25 kW Dish-stirling thermosolar power generation system in Beidaihe.The test results of this paper are compared with results from the same type systems that are advanced from abroad. The result shows: the solar tracking system designed in this paper has a high practical value which can be successfully worked on a 25 kW Dish-stirling thermosolar power generation system with tracking accuracy around 0.5°, and all the functions are successfully realized.