基于DSP的定日镜跟踪控制系统研究

研制了一种用于塔式太阳能热发电站中定日镜的新型跟踪控制系统,该系统采用开-闭环结合的控制方式,以DSP2812为控制器,并针对定日镜谐波传动机构在控制过程中其参数在一定范围内具有"自相似性"的特性,系统采用了复合式分段控制算法,即:在开环时输出脉冲常量快速定位,在闭环粗调时采用增量式数字PID算法,在闭环精调时利用分形修正的PID算法,最终实现定日镜的精准跟踪。经测试表明,该系统跟踪精度优于3.5mrad,25度阶跃响应常数小于103ms,超调量小于3.2%,半振荡次数小于2次。该文主要成果已在国家863计划重点项目示范基地中经过现场测试检验。

STUDY ON TRACKING CONTROL SYSTEM OF HELIOSTAT BASED ON A DSP-CONTROLLED

A new tracking control system of heliostat used in the solar power tower plant was developed . The control mode of open-closed loop combined was adopted in this system and DSP2812 was used as system controller. The control system considered that control parameters varied in a certain range had the characteristic of fractal geometry during the control movement process of heliostat harmonic drive gear, according to this characteristic, system adopted compound subsection control algorithm, namely: output pulse constant to locate rapidly in the condition of open loop, adopting increment PID (Proportional-Integral-Diffrerential) and fractal modified PID algorithm respectively in the condition of cursory and precise closed loop, achieving accurate tracking at last. The experiment showed that tracking precision is higher than 3.5mrad, at the meantime, 25° step response constant of this control system is less than 103ms, overshoot is less than 3.2% and the time of half surge is less than 2 times. The major achievement in this paper has been successfully tested and provedin the demonstration.