大型射电望远镜参数变化及非线性特性影响下的多策略高性能稳定控制研究

During the operation of a radio telescope, a number of physical parameters such as inertia, damping and the like will change with the change of the antenna attitude, so the performance of the traditional servo control system will be degraded.Using the same set of control parameters to deal with different operating modes of the radio telescope, limiting the performance of the antenna to enhance;Though the influence of nonlinear characteristic of transmission system can be compensated or avoided by means of hardware, the control algorithm itself still needs improvement for high-precision control of large-aperture antenna.The subject comprehensive utilization of a variety of control methods, multi-way to improve the large-aperture radio telescope antenna performance, to explore different control and compensation between the relationship and impact:Using the quantitative feedback theory, a controlled model and an external disturbance model with uncertain parameters are established to ensure that changes in the system parameters do not affect the performance of the antenna and resist external disturbances.The nonlinear dynamic control method is used to compensate the nonlinear characteristics of the system to improve the system stability and control accuracy.According to the antenna common mode of operation, set different control strategies, targeted to improve system performance.

射电望远镜运行过程中，多项物理参数如惯量、阻尼等均会随天线姿态改变而发生变化，传统伺服控制系统会因此性能下降；使用同一套控制参数应对射电望远镜不同运行模式，限制了天线运动性能的提升；天线传动系统的非线性特性影响虽可以通过硬件实现补偿或回避，但针对大口径天线的高精度控制需求，控制算法本身仍有继续改进的必要。本课题综合利用多种控制方法，多角度提高大口径射电望远镜天线运动性能，探索不同控制、补偿方式间的相互关系与影响：利用定量反馈理论，建立具备参数不确定区间的被控模型与外部扰动模型，确保系统参数变化不对天线运动性能造成影响，抵抗外部扰动；使用非线性动态控制法，补偿系统非线性特性，提高系统稳定性与控制精度。根据天线常见运行模式，设定不同控制参数，有针对性的提高系统性能。

为提高大口径射电望远镜指向精度，需解决其运行过程中的参数摄动问题，以及非线性特性对精度的影响。本课题对望远镜天线不同工况下，利用长短周期网络，实现天线非线性建模；利用多模型切换解决被控对象参数摄动的问题；利用模型预测控制算法解决多模型切换稳定性问题。之后，利用粒子群算法，求解控制器非线性代数输出值，最后，参考并简化自适应动态规划结构，实现控制器求解速度的提高。完成了天线多工况多策略控制及非线性补偿的目标。