Wind disturbance control of Multiplexed Survey Telescope prototype based on active disturbance rejection control

Wind disturbance is the major factor that affectsthe pointing and tracking accuracy of ground-based astronomical telescope. In order to improve the disturbance rejection ability of the telescope, a double closed-loop control strategy based on Active Disturbance Rejection Control (ADRC) for position and current control is designed. The current loop retains its requirement for excellent and rapid response capabilities with the continued use of PI control. In the position loop, a state observer is employed to predict the total system disturbance and provide compensation, which improves the control system's disturbance rejection ability. The simulation results reveal that the equivalent sinusoidal tracking error of the ADRC controller has an RMS value of 0.0976" and a PI controller of 0.528" when tracking a sine curve with a velocity of 0.05°/𝑠 and an acceleration of 0.025°/𝑠 ² under wind disturbance with an average wind velocity of 10 𝑚/𝑠. The RMS of the ADRC without wind disturbance is 0.0854" and the PI is 0.2369". Through the simulation, the results indicate that the proposed ADRC controller can effectively reduce the impact of wind disturbances on the system's tracking accuracy.