LPV Model-based Fault Diagnosis And Fault-tolerant Control Of Satellite Attitude Control System

With the rapid development of space science, more and more types of satellite was launched into space, the space environment is complex, when the satellite in orbit will inevitably be subject to outside interference or certain parts of their own failure, and the satellite attitude control satellite system is the key to ensure stable operation, the probability of failure will be higher, so for fault diagnosis and fault tolerant control of satellite attitude control system is particularly necessary. In this paper, a method of LPV model-based satellite attitude control system fault diagnosis and fault tolerant control study.Object of this study was oriented axis stabilized satellites, the first of modeling the attitude control system were studied, the establishment of a satellite attitude dynamics model attitude kinematics model and implementing agencies; and further clarified the satellite attitude control system possible the site of the occurrence of the fault, including the implementation mechanism(flywheel), direction sensor(gyro) and the star sensor, the establishment of a corresponding fault models; Finally, the simulation analysis.Use previously derived relationship dynamics gesture designed fault detection observer for fault detection flywheel; thinking based on observation and dedication, designed observer group, decoupling the flywheel different fault shaft, a flywheel fault isolation, in the end is what distinguishes a flywheel shaft failed; and simulation analysis.The use of attitude kinematics model previously deduced designed fault detection observer for detecting gyro failure. And in accordance with the idea of adaptive observer is designed observer group. For constant drift increases this failure, the success of which distinguish one axis gyro fails, and can estimate the severity of the problem; and the simulation analysis.Finally, the satellite attitude control system fault tolerant control study using based fault-tolerant control method for pseudo-inverse method, stuck or idling of failure for the actuator(flywheel), fault detection derived information, the fault information reconstruction, detailed derivation of additional control law, and the use of additional control law compensation fault information, the failure to achieve regulation. The simulation results can know, since the control law regulation, flywheel angular velocity deviation is very small, but there is still bias and quaternion faster settling time, show that the designed control law to the flywheel stuck idling or has a good fault tolerant effect.