服役载荷与结构参数对塔式太阳能定日镜光学精度的影响  

Influence of Service Load and Structural Parameters on Optical Accuracy of Solar Tower Heliostat

作　　者：李彬[1] 颜健[1] 周炜 彭佑多[1] Li Bin;Yan Jian;Zhou Wei;Peng Youduo(School of Mechanical Engineering,Hunan University of Science and Technology,Xiangtan 411201,Hunan,China)

机构地区：[1]湖南科技大学机电工程学院,湖南湘潭411201

出　　处：《光学学报》2024年第6期308-317,共10页Acta Optica Sinica

基　　金：国家自然科学基金(52105097);湖南省自然科学基金(2023JJ30260);湖南教育厅重点项目(22A0343)。

摘　　要：以典型的20 m^(2)小型定日镜为对象,采用光-机集成建模方法,研究了自重和风载荷联合作用下定日镜的服役光学精度特性,综合考虑了定日镜工作高度角、风压大小和关键结构参数的影响。结果表明,沿镜面横向的斜率误差分量D_(x)要明显大于沿其竖向的D_(y),螺栓数量N增加对D_(x)影响不显著,但能显著减小D_(y),反射镜面自身刚度弱是其服役光学精度下降的主要原因;机架中角钢型材的边长a在30~50 mm之间对光学精度影响较小,但厚度t对光学精度的影响较为显著。定日镜结构变形与镜面斜率误差均随着风压载荷的增加而线性增加,且不同高度角β下总镜面斜率误差变化曲线斜率基本一致;仅在自重作用下,高度角0°~90°内总斜率误差能控制在1.45 mrad以内;镜面变形与其斜率误差分布规律完全不同,镜面斜率误差与镜面变形之间并非呈线性正比关系,采用光学精度进行评价或指导定日镜结构优化设计是最佳途径。Objective Solar tower thermal power generation technology has the advantages of high light-electricity conversion efficiency and flexible energy storage,and it has become one of the most important ways to achieve the goal of carbon peak and carbon neutrality.The heliostat is the core device to realize solar energy pooling in the whole tower photovoltaic power plant.It can focus the solar energy within a certain range around the heat-absorbing tower,so as to complete the light-heat conversion in the heat-absorbing device with high quality.However,the heliostat is susceptible to structural deformation due to self-weight and wind load during service,and the distance between the heliostat and the heat-absorbing tower is relatively large.The small deformation of the reflecting mirror surface of the heliostat will lead to the reflected solar beam falling on the heat-absorbing device,which will directly lead to a decrease in the light-concentrating efficiency of the heliostat and a deterioration in the quality of the light-energy distribution of the heat-absorbing device.Therefore,it is important to investigate the service optical accuracy of the heliostat under self-weight and wind load,which can provide a basis for its lightweight and high-precision design and service performance guarantee.Methods In this study,we study a typical lightweight small-scale heliostat of 20 m^(2).First,we establishe the threedimensional(3D)model and the finite element simulation model.Second,we adopte a universal optical-machine integration modeling method previously proposed by the team to consider the service deformation of solar concentrators and establishe an optical-mechanical integration analytical model of the heliostat.We also investigate the influence of the key structural parameters under the effect of self-weight and wind load on the optical accuracy of the heliostat in service.The structural parameters include the spacing d and the number N of the three rows of supporting bolts at the bottom of each plane mirror,the structural

关 键 词：光学器件 塔式定日镜 服役载荷 光-机集成 镜面斜率误差 光学精度 

分 类 号：TK513.1[动力工程及工程热物理—热能工程] O435.1[机械工程—光学工程]