Near spacecraft fault diagnosis and fault-tolerant control method

The invention discloses a near spacecraft fault diagnosis and fault-tolerant control method. Firstly, a dynamical model of an attitude control system of a reentry phase of a near spacecraft is established and the dynamical model of the attitude control system is transferred to a nonlinear equation in a general type through coordinate transformation; secondly, a fault model with actuator invalidation and actuator dynamic damage existing simultaneously is established; thirdly, real-time online estimation of self-adaption estimation observer to actuator dynamic damage factors and actuator invalidation factors is respectively established; and finally a sliding module fault-tolerant controller is designed through the estimated actuator dynamic damage factors and the estimated actuator invalidation factors and parameters of the controller is updated in real time. According to the near spacecraft fault diagnosis and fault-tolerant control method, in the condition that when the actuator dynamic damage and the actuator invalidation occur simultaneously in a flight control system, fault information can be estimated rapidly and accurately, strong fault-tolerant capacity is achieved and an expected requirement of the flight control system is reached.