LQG/LTR control law of drag-free satellite based on linearized orbital motion equation

Drag-free satellite can achieve a high flight precision, offering an ideal stage to some scientific experiment. For control of LEO drag-free satellite in accelerator mode, this article builds a LQG control law, which is based on the linearization of orbital motion equation. J₂ perturbation is considered in the linearization, and the drift of accelerator is estimated by Kalman filter. LTR is introduced to improve robustness of the system. Taking a satellite of 260km altitude as an example for simulation, considering atmospheric noise, thruster noise and measure noise, maximum position error is 1 μm, and maximum control acceleration is 5 μm/s².