中继卫星H∞姿态稳定控制研究

 主要研究中继卫星H_∞回路成形姿态稳定控制问题。中继卫星具有弱阻尼的柔性模态频率和晃动模态频率,并且模态频率具有不确定性,同时系统增益也存在有较大的变化。首先利用拉格朗日方程建立了该卫星的动力学方程,描述了系统存在的结构不确定性,然后设计了H_∞回路成形控制器。在设计过程中,首先提出了控制系统所需要满足的鲁棒稳定性和鲁棒性能指标;随后利用H_∞回路成形理论设计了卫星的姿态稳定控制器,利用ν间隔度量方法对所设计的控制器进行了降阶处理,并且对所设计的控制器进行了鲁棒稳定性和鲁棒性能分析;最后通过数学仿真证明了所设计的控制器的有效性。

Study of H∞ Attitude Stabilization Control of TDRS

The problem of H_∞ loop shaping attitude stabilization control for Tracking and Data Relay Satellite (TDRS) is investigated. The TDRS has lightly damped flexible modal frequencies and sloshing modal frequencies. The modal frequencies have large uncertainties, and so is the system gain. Firstly, the dynamic model of the satellite is established using the Lagrange Equation, and the structured model uncertainties are described, then the H_∞ loop shaping controller is designed. In the process of designing H_∞ loop shaping controller, the robust stabilization and robust performance specifications which need to be satisfied by the control system of the flexible satellite are brought forward in the first step. Subsequently the attitude stabilization controller of the flexible satellite is designed using the H_∞ loop shaping theory, then the order reduction of the controller designed before is done by the ν gap metric, and the robust stability and robust performance are analyzed. Finally, the mathematical simulation is conducted to demonstrate the validity of the H_∞ loop shaping controller.