一种故障干扰解耦的航天器主动容错控制方法

An active fault tolerant control method for spacecraft with fault and disturbance decoupling

摘要:

为提高航天器系统的可靠性,研究一种干扰影响下的航天器主动容错控制技术. 首先,为实现干扰下的故障诊断,减小航天器系统故障检测到故障估计之间的时间延迟,通过将故障扩展为系统状态量,设计未知输入观测器,进行航天器故障检测及估计单元一体化设计. 其次,考虑到此方法无法实现对干扰的估计,且仅能解决可导的故障类型,进一步设计新型的自适应滑模未知输入观测器,能够保证对干扰及故障的同时解耦估计,也可以解决更广泛的故障类型. 最后,考虑观测器观测过程中的估计误差,设计了多变量终端滑模容错控制器,提高了控制性能. 仿真结果表明:所设计的主动容错控制策略能够实现干扰影响下的故障诊断,可以保证航天器控制性能的快速恢复.

Abstract:

To improve the reliability of spacecraft system, an active fault tolerant control technique for spacecraft under the influence of disturbance was studied. First, in order to realize fault diagnosis under disturbance and reduce the time delay from fault detection to fault estimation, the concerned faults were extended to state vectors, and an unknown input observer was proposed for the integrated design of fault detection and fault estimation unit. Then, considering that the method needs to be further processed for interference estimation and can only solve the differentiable fault type, a novel adaptive sliding mode unknown input observer was designed, which can ensure the estimation of fault and disturbance decoupling at the same time and deal with a wider range of fault types. Finally, in view of the estimation error of the observer, a multivariable terminal sliding mode fault tolerant controller was proposed to improve its control performance. Simulation results show that the active fault tolerant control technique could realize fault diagnosis under the influence of disturbance and ensure the rapid recovery of control performance.