节点文献

基于视日运动轨迹的双轴太阳跟踪系统的研究

Research on Two-axis Sun-tracker Based on the Solar Trajectory

【作者】 曾利霞

【导师】 钟毓宁; 丁善婷;

【作者基本信息】 湖北工业大学 , 测试计量技术及仪器, 2012, 硕士

【摘要】 随着全球范围内的能源问题日益严重,太阳能作为一种清洁无污染的新能源正越来越广泛地被利用。太阳能集热器这类最主要的太阳能热利用产品的质量检测显得尤为重要。车载太阳跟踪系统是流动式太阳能热利用产品热性能测试系统中的一个关键子系统,对提高检测效率具有重要意义。论文在现有太阳跟踪研究基础上设计一套基于视日运动轨迹的太阳集热器测试系统数控双轴太阳自动跟踪系统,能够实现对太阳的实时跟踪。主要工作围绕以下几方面展开。首先对我国的能源利用现状、太阳能热利用产品检测现状进行说明,并对现有的太阳跟踪装置从原理到实现方式进行对比分析。确定本车载跟踪系统选用视日运动轨迹跟踪方案。在此基础上,给出了太阳位置的计算方法,特别是对算法中富有争议的时差值进行计算,用一年的数据与天文年历对比,取最优算法。采用间歇式的控制方式以及双轴转动机构模型对跟踪系统进行硬件设计,其外形尺寸由承载车辆的空间大小决定。利用工控机控制两个轴的伺服电机转动,实现双轴跟踪。基于Labview语言编写各模块的软件程序并进行调试。实现了手动调整以及根据地理经纬度、计算机时间实时计算太阳位置并对其进行自动跟踪的功能。在实际环境中,用所设计的双轴跟踪系统进行追日试验,对其跟踪精度进行分析,试验结果表明,所设计的双轴跟踪系统能够实现试验环境条件自动判断,各项功能满足项目要求,跟踪精度在±2°以内。目前,本文设计的车载双轴太阳跟踪系统已集成于流动式太阳能热利用产品热性能测试系统,使用方便,增加了太阳集热器平板能量吸收率,满足热性能测试要求。

【Abstract】 With the growing of energy problem worldwide, solar energy is becoming morewidely used as a clean and non-polluting energy. Quality testing for the mostimportant use of solar thermal products such as solar collectors is particularlyimportant. The vehicle sun-tracker is the key component of the mobile thermalperformance testing system for solar thermal products. It has a greatsignificance to improve the detection efficiency.A numerical control two-axis automatic sun-tracker based on the solar trajectorywas designed for solar collector testing system on the existing study of sun tracking. Itcan realize real-time sun tracking.Firstly, the status of energy utilization in our country and the current situation ofsolar thermal products’ quality were described. Existing sun-tracking devices wereanalyzed comparatively from their principle to implementation. The tracking programbased on solar trajectory was selected for the system. On this basis, the calculationof the sun position was given, especially, the controversial algorithms for timedifference were researched,the optimal algorithm which was not far off astronomicalalmanac was selected by comparing time difference data of one year.The hardware of the tracking system was designed using the intermittent controlmode and two-axis rotating model,size of the system was decided by the carryingvehicle’s space. Servo motors’ rotation of the two axes was controlled by industrialcontrol computer to achieve the two-axis tracking. The software program for eachmodule was wrote in Labview-based language and debugged. The system realized thefunctions including manual adjustment and automatic tracking based on the position ofthe sun calculated by the computer using the geographical latitude, longitude and time.Two-axis tracking system designed was used for tracking test in real environment.Its tracking accuracy was analyzed. It was showed that the two-axis suntracker designed can test environmental conditions automatically, its variousfunctions met the project’ requirements. Tracking accuracy of the system wasdetermined to be less than±2°.The vehicle two-axis sun tracker has been integrated in the mobile thermalperformance testing system for solar thermal products. It’s convenient to use.Energy absorption rate of flat panel solar collectors are increased. Testing requirementswere met.

节点文献中: