太阳能塔式电站轮胎面定日镜的设计及性能分析

为了提高定日镜的聚光性能，研究了可校正离轴象散的轮胎面定日镜.通过计算聚光场四个典型位置的定日镜与吸热器的间距和阳光在镜面上的全年入射角变化范围，确定定日镜的焦距和视场，使用ZEMAX软件设计出轮胎面定日镜，并分析其聚光性能.与球面定日镜相比，轮胎面定日镜的聚光性能有很大提高：不仅光斑面积变小，而且可将光斑最小点从视场边缘移至视场中心附近.提出了轮胎面定日镜的制作方法，实践证明了该方法的可行性.

Design and Performance Analysis of Toroidal Heliostat in Solar Tower Power Plant

For improving the concentrating performance of the heliostat in the solar tower thermal power generation technology,the toroidal heliostat for correcting off-astigmatism was investigated.The four heliostats were chosen which locate at four characteristic positions of a concentrator field.The distances between the receiver and the observed heliostats and the annual change ranges of sunlight incident angle onto the heliostats were calculated.According to the calculated values of distance and angle the focal length and the field of view of the designed heliostats can be determined.The toroidal heliostats for these four positions were designed with the software ZEMAX.The optical performance of the toroidal heliostat was analyzed.Compared with the spherical heliostat,there are considerable improvements:not only the size of focal spot is reduced,but also it is possible to shift the minimum focal spot from the edge to the center of the field of view.The manufacture method for the toroidal heliostat was proposed and the feasibility was demonstrated by the experience.