Research On Multiple Fault Detection And Isolation Methods In Closed-loop System

With the continuous formation of factors such as the complexity of the system structure,the quantification of data renewal,and the scale of industrial development,the requirements for the safe operation of the system continue to increase.Only in a more reliable and safer environment,then work efficiency,production efficiency,transmission efficiency,etc.will be improved.So,the application of fault diagnosis technology to real life has great significance.This article will take the smart car and closed-loop control system as the research object,and carry out research on the fault detection and isolation of the automatic control system.This article takes the modern automatic control system fault diagnosis as the research background,takes the intelligent car system and the closed-loop control system as the research object,uses the space geometric method and the linear system theory knowledge as the main tools and means,and takes the intelligent control system and the closed-loop control system fault detection and isolation as the purpose,then relevant fault diagnosis techniques are researched,and future research ideas are proposed in the research of fault diagnosis of closed-loop control systems.This paper mainly uses space geometry method to carry out fault diagnosis technology research.Firstly,based on the linear time-invariant system,the fault model of the corresponding system is extended,the fault features are extracted,the invariant subspace and the unobservable subspace are solved by the space projection geometric properties;then the residual generator is established and the residuals are designed according to the fault characteristics.Correspondence of the fault;Then decoupling of output residuals from noise and interference is achieved through a space decoupling algorithm.Here,the paper mainly focuses on the following two points: the space geometry method applied to fault diagnosis algorithm research.1)For a class of intelligent systems using smart cars as an example,a linear time-invariant system is used to build the motion model of the car,and the main components of the car,such as the left wheel,right wheel,and motor,are used as the main test points to construct the fault system model with outside interference or noise.The residual generator is designed to calculate the system-related parameters through the space mapping algorithm.The output residuals areformed by the difference between the faulty system and the normal system.The safe operating threshold is set,the residual value is compared with the threshold,and the fault is detected.During the movement of the trolley,the data of the main observation points are collected and measured.When a given fault situation is given,the validity of the given algorithm can be verified through simulation.Finally,the fault detection and isolation of the intelligent vehicle system can be achieved.2)For the output feedback of the closed-loop control system,the feedback amount can adjust the input and output of the system and can make the system run in a stable state.However,if the system fails,the fault information will be accompanied by the system feedback to the input,as a kind of the effective information continues to exist in the system information transmission,which may lead to further deterioration of the system fault or trigger a new fault.Here,according to the system transfer function,the corresponding compensator is designed so that the effect of the compensation link on the system and the influence of the disturbance on the system cancel each other,so that the impact of the system on the system can be eliminated or greatly affected.The residual generator is designed,and the coupling relationship between the residual error and the fault in the output feedback system is given.The one-to-one mapping relationship between the residuals and the faults is realized according to the inclusion relationship of the characteristic subspace,and the realization of the fault detection and isolation is verified through simulation,which shows that the fault diagnosis results of the closed-loop system can reduce the impact of the fault on the system to some extent.