Abstract:In order to solve the problem of satellite actuator failure, a fault estimation and control law reconstruction method based on the system state space model and adaptive observer is proposed, so as to achieve the goal of replacing hardware redundancy with algorithm reconstruction. In view of the partial failure of the satellite actuator, the attitude dynamics model and the actuator failure model are established and an adaptive fault diagnosis observer is designed. By solving the linear matrix inequality to obtain the parameters of the observer, the fault estimation is effectively carried out, and the stability of the error system is proved by using the Lyapunov theory. Based on the obtained fault information, the controller is reconstructed to compensate for the degradation of system control performance caused by the failure of the actuator, and the system can achieve satisfactory dynamic performance indicators. Finally, a satellite attitude control system is taken as an example for simulation verification, and the results show that the proposed method can realize fault estimation and compensation control. Compared with traditional hardware backup, this algorithm reconstruction and compensation method has a clear principle, which can reduce system complexity and increase economic benefits.