鲁棒PD+卫星姿态快速机动控制器设计

Robust PD+ controller for satellite attitude fast maneuvering

针对控制力矩与角速度受限情形下的卫星姿态快速机动的控制问题,本文对传统PD控制器进行了改进,采用姿态机动的匀速与减速运动过程的方法大幅度提升系统收敛速率,设计PD+控制器使得系统状态能够沿着期望的滑模面进行运动,并通过构造Lyapunov函数对其进行证明,从而实现对PD控制器收敛时间的估计,并实现40%以上的系统收敛时间提升。在存在转动惯量不确定性与外部干扰力矩的情形下设计PD+控制器实现对于未知扰动的抑制。同时考虑到卫星正常运行对于姿态角速度与控制力矩的限制,证明了姿态控制参数与角速度范数之间的关系,给出了控制力矩与角速度受限情形下的控制律。最后通过数值仿真验证本文提出控制算法的有效性。

To address satellite attitude control issues under control torque and angular velocity constraints,a traditional PD controller is modified in this study. The convergence rate of the traditional PD controller is improved greatly by designing uniform and decelerated motions through attitude maneuvering. The PD+ controller is designed so that the system state could converge along the designed sliding plane,which is proven by establishing the Lyapunov function. Thus,the convergence time could be estimated. Simulation results demonstrate that the convergence time could be improved by more than 40%. A robust PD+ controller is designed under the conditions of uncertain moment of inertia and external disturbance torque to restrain unknown disturbance. As the satellite attitude angular velocity and control moment are restricted by the normal operation of the satellite,the relation between the attitude maneuvering and norm of angular velocity is proven. Thus,the control law under restriction of control torque and angular velocity is given. The effectiveness of the proposed controller is validated by simulation results.