基于跟踪微分器的姿控喷管故障检测

Fault Detection of Attitude Control Nozzles Based on Tracking-Differentiator

针对航天飞行器姿控喷管故障的检测问题,提出了一种基于跟踪微分器(TD)的故障检测方法。该方法在考虑测量噪声、安装误差、转动惯量误差、姿控喷管特性、质心偏移等因素的基础上,设计了带低通滤波器的跟踪微分器,用来估计姿控喷管的输出力矩,并根据上述对象的实际偏差设计了无故障时估计力矩随指令力矩变化的力矩包络,即在无故障时估计力矩不会超出包络,通过检测估计力矩是否超出包络来判断是否发生故障。通过数学仿真,表明该方法能有效检测航天飞行器姿控喷管的故障,检测成功率高并且几乎没有误检。

In this paper,a fault detection method is proposed based on tracking differentiator(TD)for a nozzle-controlled space vehicle.Taking considerations of measurement noise,installation error,index of attitude control nozzles,moment of inertia as well as center of mass deviations,a tracking differentiator with low pass filter is designed to estimate the actual torque of output of the attitude control nozzles.Based on the actual deviations mentioned above,a torque envelope is formulated which changes along with the control command.A fault is then detected online as long as the estimated moment goes beyond the envelope.The mathematical simulation shows the effectiveness of the approach with high rate of fault coverage.