Design Of Sun-track System In The Solar Power Engineering

Solar energy is a kind of pollution-free, green and renewable energy with wideapplications. Solar has its own features, such as intermittent, spatial non-uniformity anduncertainly light intensity. How to improve the efficiency of solar energy is a technicalchallenge. Now some fixed solar energy collecting systems can’t receive as much energyas possible, so their efficiency is comparatively low. There is plentiful solar energyresource in China. How to make full use of solar energy becomes an important R&Dproject, which will solve energy crisis in the future.The purpose of this project is to design a high precision, simple structure, inexpensivesun tracking system, which will improve the currently efficiency of the solar power system.It can achieve real-time tracking performance in a variety of weather and environmentconditions. The experimental prototype adopts STC12C5A40S2, which is the corecontroller of the whole system.Two sun tracking modes will be discussed in the experimental prototype. One isoptoelectronic detection mode, and the other is the sun angle tracking mode. This systemcan operate in complex weather conditions. The optoelectronic detection mode is operatedin sunny day, while a cloudy day the tracking will be according to the sun position throughcalculating. The two combined modes can fully achieve the aim of solar tracking. In theoptoelectronic detection mode, the optical fibers lead sunlight energy into photoelectricsensors (The main principle is based on “a sun sensor and its measurement method”, whichis an intelligent property and it has already been patented). The difference value of opticalenergy gained by each pair of opposite optical fiber is an important original data processedby MCU. According to the operation results from the MCU, the experimental system cansense the direction of the sun. Then the panel is driven by two step motors to keep it perpendicular to the sunlight. While in sun angle tracking mode, the altitude angle and theazimuth angle of sun are calculated by the software with real-time dynamic data providedby a GPS module. Two step motors drive the solar panels to track the sun. The design ofsoftware is modularization and C51language is adopted in the monitoring program.This paper will describe the principle of the tracker, the design of circuit, thedebugging of prototype, and the mechanical structure of the system. Finally theexperimental prototype operates perfectly, and the experimental result shows it canbasically achieve the expected function of the subject. In the future, this technology will beimproved and applied in further solar power system.