微纳卫星姿态控制系统的精细抗干扰容错控制方法

Abstract

It is difficult to diagnose and accommodate the faults if disturbances and faults exist simultaneously in the controlled plants. This paper concerns the time-varying fault diagnosis problem for the attitude control system of microsatellites. First of all, a fault diagnosis observer for abrupt fault of the reaction flywheel is designed. In order to reject the disturbance of vibration from the reaction flywheel, a disturbance observer should be designed. Then a subtle fault diagnosis and tolerant control method is presented for the attitude control system including the parameter uncertainties due to the moment-of-inertia variation of microsatellites, fault of the reaction flywheel and the disturbance of vibration from the reaction flywheel simultaneously. A composite fault tolerant controller is constructed by integrating a fault accommodation from diagnosis observer with additional disturbance rejection and attenuation performance for two different types of disturbances. Then the fault can be accommodated and the multiple disturbances can be rejected and attenuated simultaneously. As a result, the controller can be easily solved via convex optimization based on linear matrix inequality. Simulations for an attitude control system of microsatellites are given to demonstrate that the fault can be accommodated readily and the disturbances can be rejected and attenuated simultaneously.