带有大型挠性网状天线航天器的鲁棒H_∞控制方法

Robust H-infinity control design for spacecrafts with large flexible netted antennas

针对带有大型挠性网状天线航天器存在的挠性结构不确定性问题,提出了基于比例微分(PD)结构滤波器的鲁棒H∞双层反馈控制方法,第1层采用经典的PD+结构滤波器,确保刚体部分双积分环节稳定,第2层在提取第1层标称模型后,给出通用加权函数,通过构造增广模型得到鲁棒H∞控制器.该控制器结构简单,适合工程应用.通过仿真表明,本方法相对于传统PID+结构滤波器方法能够快速稳定三轴姿态;当结构参数变化较大且三轴姿态偏置为动态时变时,有可能导致传统方法失稳,而本方法具有较强的鲁棒适应性,仍能完成航天器天线的指向任务.

To deal with the flexible structure uncertainty of the spacecrafts with a large flexible netted antenna, we propose a robust H-infinity double feedback controller based on a typical proportional and derivative （PD） controller with structure filters. The first layer of the controller is built with a typical PD controller with structure filters to ensure the stability of the second-order integral system of the rigid part of the spacecraft. Based on the normal model obtained from the closed system with the first layer control, we give the general form of weight functions and construct the incremental model for designing the robust H-infinity controller which is called the second layer controller. The proposed robust controller is suitable for spacecrafts with momentum wheels. It is shown by simulations that the given method provides rapid stabilization for three-axis attitude control, and is more robust than the typical PID controller in performing the center-pointinjz task of the flexible antenna.