基于比例积分观测器的卫星姿控系统鲁棒故障重构

Robust fault reconstruction design for satellite attitude control systems based on proportional integral observer

针对卫星在轨运行出现执行机构故障问题,提出了一种基于观测器的卫星姿控系统鲁棒故障重构方法。首先,考虑卫星出现空间干扰、测量干扰以及噪声,建立欧拉离散时间卫星姿控系统模型。其次,设计一种离散比例积分观测器(proportional integral observer,PIO)实现卫星姿态角和姿态角速度估计,并利用前一时刻的故障重构值和输出估计误差迭代更新当前故障重构信息。然后,采用干扰解耦思想设计离散PIO解耦部分空间干扰,并利用H∞技术抑制剩余干扰和测量噪声的影响。另外,利用线性矩阵不等式工具箱求解了部分观测器增益矩阵。最后,仿真结果验证了所提故障重构方法的有效性。

The problem of observer-based robust actuator fault reconstruction in the satellite attitude con-trol system （ACS）is investigated.Firstly,a discrete-time model for satellite ACS subject to space disturbance torques and measurement noises is established.Secondly,a discrete proportional integral observer （PIO）is con-structed to simultaneously estimate satellite attitude angles and attitude angular velocities,and the current fault reconstruction signal is further updated by its previous information and output estimation error.Thirdly,based on the disturbance-decoupling methodology,the proposed PIO is partially decoupled from space disturbance torques,and then the PIO is designed to attenuate the influence of the remaining part of space disturbance torques and measurement noises via H ∞ technologies.In addition,observer gain matrices are conveniently com-puted using standard linear matrix inequality tools.Finally,simulation results validate the effectiveness of the proposed PIO-based fault reconstruction approach.