Research On Interval Hybrid Robust Fault-tolerant Control Of NCS Under DETCS

Networked control systems(NCS)fault-tolerant control is an important research topic of intelligent manufacturing field,because of the high integration control,strong adaptability,easy maintenance and management,which promoted the rapid development in the field of engineering,but subject to the system and network complexity,component equipment failure,communication constraints,time delay and internal parameter uncertainties are still focus on the problems in this field.In view of this,under the constraint of discrete event-triggered communication mechanism(DETCS),this paper studies the problem of collaborative design of control tasks and communication service quality under the fault of arbitrary actuator by using the fault tolerance of interval control with active and passive hybrid thought.The main contents are as follows:1)According to the prior knowledge base,the partitioning algorithm is used to classify the fault data to create a representative knowledge base of common faults.At the same time,the passive and active mathematical expressions of actuator fault with equivalence relation are established,and then the closed-loop fault NCS model with parameter uncertainty,stochastic delay,external disturbance and switching jitter is designed under the action of DETCS.Furthermore,based on the control policy and FDO(fault detection observer),the common fault model is matched to complete the scheduling task.2)The strategy of "off-line design,online scheduling" is used to design a robust and less conservative fault-tolerant controller with active and passive interval hybrid characteristics,which can quickly detect faults under the action of FDO,so that when the common fault occurs,the fault tolerant controller of the interval can be quickly invoked and the conservatism of the result can be reduced.When there are other faults in the common fault division range,the compensation algorithm is used to reconstruct the controller.3)Considering the influence of network constraints and event triggering conditions,fault-tolerant control under variable delay problem is studied.Under actuator failure and external disturbances is build respectively has the probability distribution of the fault observer and interval fault tolerant control law,and by using the robust control and H2 control method,designed the random time delay replication main passive interval hybrid robust generalized H2/H? less conservative fault-tolerant controller,and ensure the system on the basis of the mean square exponential stability has certain dynamic characteristics.4)Reference the thought of smooth transition,in the system for scheduling policy effect caused by the switching transient response between different controller to make the smooth study,for the fragile characteristics of fault-tolerant controller design,in the event of actuator failures,the interval of fault-tolerant controller corresponding smoothing processing,can ensure the quickness of switching process on one hand,on the other hand can soften the transient switching process between the controller make the system output response tends to smooth;At the same time,with the help of DETCS communication mode and satisfied performance index constraints,the fault-tolerant control method of NCS can not only save network resources but also ensure that each controller has H2/H? performance at the switching point.