倾斜轨道对地指向小卫星对日跟踪姿态控制算法

Sun-tracking Attitude Control Algorithm for Inclined-orbit Small Satellite with Nadir-pointing

固定安装太阳电池阵形式的对地指向小卫星,运行在倾斜轨道时太阳电池阵光照条件恶劣,限制了小卫星的应用。文章研究了对地指向小卫星姿态跟踪控制,提出了控制算法。首先,对太阳电池阵法线和太阳方向矢量进行分析,得到最优的偏航角、偏航角速度和偏航角加速度。然后,基于卫星姿态动力学给出了3个互相垂直安装的反作用飞轮控制律,并利用Lyapunov稳定性理论证明了闭环控制系统的渐近稳定性。以某小卫星为例,对控制算法进行验证,结果表明:文章提出的控制算法具有很好的实用性,控制律有效,能达到太阳电池阵跟踪太阳的效果。

Solar array without yokes is widely used on the small satellite with nadir-pointing,but low sunlight efficiency is the main application constraint for inclined-orbit small satellites.In the paper the attitude tracking control problem of small satellite is analyzed,then a control algorithm is put forward.The relation between normal of solar array and the vector of sun direction is analyzed,and the ideal yaw angle,yaw angular velocity and yaw angular acceleration are derived.The control law for 3 vertically installed reaction wheels is developed based on the satellite attitude dynamics.Lyapunov stability theory is used to prove the asymptotic stability of the closed-loop control system.A small satellite is used to verify the control algorithm.The results show the validity of the control algorithm and the effectiveness of control law,and that the solar array can track to the sun effectively.