微小故障下的深空探测航天器闭环主动故障检测

Closed-loop active fault detection of deep space exploration spacecraft with minor faults

深空探测航天器是发展空间技术、扩展人类探索疆域的重要工具.航天器运行过程中一旦发生故障,极易导致探测活动失败甚至航天器损毁,而对航天器进行早期微小故障诊断,可以有效预防重大故障的发生,对于深空探测活动的顺利进行具有十分重要的意义.本文针对模型参数不确定下的深空探测航天器系统,提出一种闭环主动故障检测方法,实现对微小故障的准确检测.通过设计合适的辅助输入信号,分别注入标称和故障模型系统,使故障系统的输出与标称系统的输出无交集,以达到故障检测的目的.此外,为减小对深空探测航天器系统产生的影响,所设计的辅助信号必须尽可能小.通过对两方面需求的考虑,在传统开环研究的基础上,加入观测器建立闭环系统,在提升对微小故障的检测能力的同时减小对系统的影响.最后,利用深空探测航天器的数学仿真验证了所提闭环方法对微小故障的检测能力,并与传统开环方法进行了对比,结果表明闭环辅助信号具有更优的性能.

Deep space exploration spacecraft is an important tool to develop space technology and expand the frontiers of human’s exploration. Once a fault occurs, the failure of exploration and even damage to the spacecraft tend to happen.Early diagnosis of minor faults can effectively prevent major faults, which is of great significance for the smooth progress of deep-space exploration activities. In this paper, a closed-loop active fault detection method is proposed for the detection of minor faults. By designing and injecting auxiliary signals into nominal and fault systems respectively, the intersection of the outputs of the two systems will be empty. In addition, the designed auxiliary signals must be as small as possible to minimize the impact on the spacecraft system. Based on the traditional open-loop research, an observer is added to form the closed-loop system to improve the efficiency of fault detection and reduce the influence on the system. Finally,the simulation results verify the efficiency of the designed auxiliary signals to detect minor faults. By comparing with the traditional open loop method,the simulation results show that the closed-loop method has better performance.