Event-triggered Control And Scheduling Of Networked Control Systems With Communication Constraints

With the increasing complexity of control system structure,a shared communica-tion network has been applied into control systems,which emerges as networked control systems(NCSs).In its framework,the sensor,controller and actuator nodes are con-nected through a network,and the measurements and control signals are transmitted and exchanged via the network,such that the resource sharing,remote control and operation can be realized.Networked control systems have a lot of applications in a variety of industrial fields,such as automobile manufacturing,process industry,aircraft design and intelligent building,and thus have been now one of the hot research topics in the control society.However,the resource constraints of the shared communication network for signal transmission may lead to some problems such as collision,waiting in queue,network congestion,multi-packet transmission and other issues.Therefore,it is necessary to s-tudy networked control systems with communication constraints from the perspective of necessary communication and networked communication scheduling strategy.Sup-ported by the National Natural Science Foundation of China "co-design of necessary communication and distributed control for networked control system with limited com-munication resources"(No.61273114),the main contents of this thesis are outlined as follows:1.As for the case where the system state cannot be measured,the dynamic out-put feedback control for networked control system with event-triggered schemes is ad-dressed.First,centralized and decentralized event-triggered schemes are proposed ac-cording to the system characteristics.Then closed-loop system models are built to couple the event-triggered scheme,time-varying delays and dynamic output feedback controller in a unified framework,respectively.By use of Lyapunov functional approach together with LMI technique,sufficient conditions to ensure exponentially stability and stabiliza-tion of the derived system are obtained.In particular,a co-design algorithm is provided to obtain the parameters of the event-triggered communication scheme and the controller simultaneously,which makes the system control performance and communication per-formance achieve the desired level.2.The problem of guaranteed cost triggered control for networked control systems in the presence of network-induced delay is investigated.First,a closed-loop system model under consideration of network-induced delay and event-triggered communica-tion scheme is given.Based on the obtained system model,an integrated system mod-el is obtained subject to network-induced delay and a hybrid communication scheme including the time-triggered and event-triggered communication schemes.Some suffi-cient conditions for stability and guaranteed cost controller design of the derived system model are presented,then a sub-optimal guaranteed cost controller is obtained by using the cone complementary linearization algorithm.The hybrid communication scheme is more effective in reducing the transmission frequency since a more recently data packet is utilized.3.The static output feedback control problem of discrete networked control sys-tems with a Markov scheduling protocol is studied.First,considering the effect of the network-induced delay,packet loss and disorder,the closed-loop system is modeled as a Markov delayed system.For the two cases,namely Markov chains with fully transi-tion probabilities and partly unknown transition probabilities,sufficient conditions are derived for ensuring the mean-square stability and stabilization of the system under con-sideration,respectively.The proposed method can lead to less conservative results be-cause of both the lower and upper bounds of the delay and the distribution characteristics of the delay being taken into account.4.The H? filtering and tracking control problem of networked linear system with an I.I.D.scheduling protocol is addressed.First,an error system is built for networked linear system with network-induced delay,packet loss and disorder,and I.I.D.schedul-ing protocol.Then,sufficient conditions for stability in mean-square with a guaranteed performance are obtained for the derived model.Based on the stability criterion,the gain of H? filter and tracking controller are obtained.Moreover,an I.I.D.scheduling optimal algorithm for minimizing H? performance is presented.