Analysis of the Feedback-Control System of the Auto Guide System of the 1m Infrared Solar Telescope of the Yunnan Observatory

The 1m infrared solar telescope being developed now is the only altazimuth vacuum-tube solar telescope in China.Its scientific objective is to achieve fine spectral analysis (including the Stokes-parameter analysis) and spatial-temporal fine-structure study of magnetic fields solar activity regions.A long-running and high-precision tracking system (AGS) is thus needed (with an accuracy of 0.3 arcsec/30 seconds, or 1 arcsec/10 minutes).The auto guide system is a key technological component for controlling a large or medium-sized telescope, such as the 1m solar telescope.In order to implement a closed-loop control of the telescope, the AGS provides feedback control signals to a control system by detecting the offsets of observed targets in the image sensor.In this paper, the model of the control system of AGS is constructed, and then the stability, transient performance, time-domain characteristics, frequency-domain characteristics, and tracking performance of the system are analyzed.In order to enhance the stability and tracking accuracy of the AGS feedback control system, a PID controller is added.Finally, the paper gives computer simulation results showing that the PID controller which is designed with certain control algorithm improves the system tracking accuracy to meet the requirement for the 1m telescope.