Antenna AC Servo System Modeling Analysis And Control Compensation

Large antennas have important value and broad application prospects in the fields of strategic early warning,deep space exploration,and radio astronomy.With the improvement of detection resolution and sensitivity requirements,large antennas are developing in the direction of high gain,high frequency band,high pointing accuracy and AC servo.However,the mutual coupling of structural parameters and environmental factors with the servo control system has become a key issue restricting the performance improvement of large antennas.In response to this problem,this thesis systematically studied the electromechanical dynamics modeling,parameter identification and adaptive control methods of AC servo-driven large antennas.The specific content include:In view of the difficulty in analyzing the impact of structural and environmental factors on system performance in the simplified model of traditional antenna servo system,considering the flexibility of the transmission mechanism and antenna mount,the rigid-flexible coupling dynamic model of large antenna was established by modal superposition method.On this basis,the electromechanical dynamic model of the antenna AC servo control system is constructed,which lays the foundation for the accurate analysis of the servo tracking performance and the control compensation research of structural and environmental factors.Aiming at the time-varying characteristics of large antenna parameters,an identification method combining recursive least squares and recursive subspace is proposed based on sensitivity analysis,which reduces the model order and realizes accurate identification of model parameters.The simulation shows that while ensuring the accuracy of the model,it also reduces the calculation amount of the identification process.The output error between the identification model and the actual model is less than 5%,which provides a basis for the online adjustment and control of the antenna servo tracking performance.The AC servo adaptive controller for large antennas is studied,the adaptive law of the inner loop controller is derived based on parameter identification,and the position loop adaptive optimal output feedback gain matrix is designed,and the simulation analysis is carried out using a 7.3m experimental antenna Under the wind disturbance of 10m/s,the pointing accuracy is improved by 63.7%compared with the traditional PID control method.At the same time,its adaptive ability is increased by more than 65%when the model parameters are perturbed.On this basis,the antenna AC servo simulation platform was developed,and the antenna AC servo system modeling,parameter identification,and control compensation modules were developed to achieve efficient analysis of the antenna's time and frequency domain performance.