三轴主惯量接近的航天器长期在轨采用惯性系的角动量管理,使用垂直于轨道面的某一主惯性轴为Y轴,建立参考的惯性系进行控制器设计,轨道摄动使轨道长周期项与时间呈近似线性关系,导致控制器输出线性累加.针对此问题,分析轨道摄动导致控制律失效的原因,参考内模原理扩维方程,重新设计最优控制方法进行惯性系的角动量管理.通过半物理仿真表明了摄动补偿方法的可行性,且角动量和姿态长期稳定性均优于补偿前.
The momentum management controller is used for large spacecrafts with orbit maintenance of long life which only have small difference in three-axis main inertia. It should be guaranteed that one inertia axis of spacecraft is strictly perpendicular to the orbital plane. Then, an inertial reference coordinate system for momentum management is established. It is observed that the drift of long-period orbit factors has an approximate linear relation to time, which leads to a linear increase of output offset of the momentum control. Therefore, the failed reasons in the design of the optimal control law are analyzed, and the state equation is augmented with internal model principle to compensate the perturbation, then the optimal quadratic regulators with pole placement method is used to design the controller according to the state space equation. Finally, semi-physical simulation validates the controller. The results show that the design of the compensation method is feasible, and the long term stability of attitude and angular momentum are achieved.