基于动量轮转速标定的轨道控制方法研究

某地球同步三轴卫星因故障导致推力器工作效率不稳定,使得采用原有方案进行向西轨道控制时姿态变化大,控制准确度降低.针对上述问题,通过分析卫星用于姿态控制的偏置动量轮的控制规律,利用星体角动量守恒条件,建立了偏置动量轮转速变化与轨道半长轴变化之间的相关性数学模型,提出了一种改进的基于偏置动量轮转速标定的轨道控制方法,同时结合姿态的稳定变化制定了轨道控制实施方案,并将其应用于实际卫星轨道控制中,取得了良好的控制效果.改进的控制方法提高了轨道控制的准确率,使得半长轴误差幅度由最大60％提高到0.2％左右,增加了姿态的稳定性,使得俯仰姿态变化幅度由最大0.7°减小到0.2°左右,降低了控制风险,减轻了地面控制人员的负担.

A Method of Westward Longitude Maneuver Based on Calibration of MW Revolution Speed

The operational efficiency of the thruster of a three-axis stabilized GEO （Geosynchronous Earth Orbit） satellite experienced instability due to malfunction.As a result,attitude variation increased and control accuracy decreased in the course of westward longitude maneuver using the existing control scheme.To solve the problem,a mathematical model is established for the relationship between MW （Momentum Wheel） revolution speed variation and semi-major axis variation using the law of conservation of angular momentum following analysis of the control law of MW for attitudes,and an improved westward longitude maneuver method based on calibration of MW revolution speed is put forward.A maneuver implementation scheme combined with attitude difference is developed and is successfully used in orbit control.Thanks to the new method,orbit control precision is increased.The amplitude of the error of the semi-major axis is expanded from 60％ maximum to about 0.2％ and changes in the pitch atutude decrease from 0.7°maximum to about around 0.2°.As a result,the risk of orbit control is significantly lowered and workload on operational staff is significantly reduced.