通用的定日镜准确方位–俯仰跟踪公式及其应用研究

Study on the General Accurate Azimuth-Elevation Tracking Angle Formula for Heliostat and Its Applications

摘要: 本文针对应用最为广泛的方位–俯仰双轴跟踪定日镜，推导出了“含镜面偏心距和其它6个典型几何误差参数的准确方位–俯仰跟踪公式”，建立了由跟踪实验数据反求定日镜的6个典型角度跟踪参数的非线性最小二乘法数学模型，并给出了2个实用的求解算法。专门设计了一个定日镜模型，并借助三维坐标机的光学测试平台，做了多组室内的激光束方位–俯仰跟踪实验。实验结果很好地验证了跟踪角度公式和估计定日镜的6个典型角度误差参数的方法。该通用的准确方位–俯仰跟踪公式，可有效补偿如定日镜的立柱倾斜、两个旋转轴的非正交等系统误差。定日镜准确跟踪公式，已成功应用于北京八达岭1 MW塔式太阳能热发电站(DAHAN电站)的100台定日镜中。

Abstract: With respect to the widely used azimuth-elevation dual axis tracking heliostats, this paper gives the accurate azimuth-elevation tracking angle formula for a heliostat with a mirror-pivot offset and other six typical geometric error parameters. A nonlinear least-squares mathematical model is es-tablished to solve the six typical angular tracking parameters of the azimuth-elevation tracking he-liostat based on experimental tracking data, and also gives the two practical numerical solution al-gorithms. We specially designed a heliostat model and with the help of optical test platform of 3D coordinate measuring machine conducted the indoor laser beam azimuth-elevation tracking expe-riments. The experimental results validated the general tracking angle formula and the method for estimating the six typical angle error parameters of an azimuth-elevation tracking heliostat. This general accurate azimuth-elevation tracking angle formula can effectively compensate the heliostat pedestal tilt, the initial angle biases of the two rotational axes and the non orthogonal angle error of the two axes and so on. This tracking angle formula has been successfully applied to the 100 helios-tats in Badaling 1 MW solar thermal tower power plant (DAHAN solar power plant) in Beijing, China.