基于未知输入观测器的导弹间歇故障诊断

摘要

针对带有未知扰动和噪声的导弹间歇故障诊断问题,设计了一种基于未知输入观测器的导弹问题故障诊断方法,系统的输入部分或全部未知情况下也能获取系统状态的称为未知输入观测器.首先,为实现对外部扰动的解耦,设计降维未知输入观测器,并通过滑动时间窗口得到对间歇故障敏感而对未知扰动解耦的残差信号;然后,在满足误报率和漏报率的条件下,通过假设检验,确定了间歇故障发生时刻和消失时刻的可检测阈值;最后,对所提出的方法进行了仿真验证.仿真结果表明,在误差允许的范围内,设计的方法能够实现对间歇故障检测,满足实时性和准确性的要求.%A robust detection method for intermittent faults (IFs) based on unknown input observer is designed to diagnose surface to air missile faults subjected to unknown disturbances and noises.At first,a reduced-order unknown input observer is designed and a novel truncated residual is constructed by introducing a sliding time window,which is decoupled from the unknown disturbances,but sensitive to the IF.Then,for the given false alarm rate and the missing detection rate,two hypothesis tests are put forward to detect the detection thresholds for the appearing time and the disappearing time of the IF.Finally,the proposed method is simulated and verified.The results illustrate that both the appearing and disappearing times of the IF can be detected quickly and efficiently in spite of unknown disturbances.