Study On Networked Control Systems Based On Event-triggered Mechanism

In recent years,under the continuous development and integration of computer technology,network communication technology,control theory and technology,networked control system has received wide attention and made great progress.However,the introduction of factors such as transmission delay,packet loss and signal quantization in network brings many problems to the analysis and synthesis of networked control systems,and brings new challenges to the technologies of network communication,signal processing and control.In particular,in order to reduce network load and reduce the use of network bandwidth,the traditional periodic sampling mechanism can no longer adapt to the development of networked control system,and it is necessary to make further research on the network control system based on event-triggered mechanism.In this paper,the control problem of networked control system based on event-triggered mechanism is studied under the restriction of network transmission delay.Firstly,based on lyapunov-krasovskii stability theorem and Time-delay system theory,the stability analysis and controller design of the system are carried out.In this paper,a new form of Lyapunov-krasovskii functionals is selected,and the sufficient condition for asymptotic stability of closed-loop systems is given by means of linear matrix inequalities(LMI),integral inequalities and mutual convex combinations.On this basis,the design method of the state feedback controller for the closed loop system is obtained by using the cone-complement linearization algorithm,the method used in this chapter is compared with some existing literatures,and the validity and applicability of the method are verified by the simulation example.Then,considering the situation of interference outside,the design problem of event-triggered controller with interval time-varying delay network control system is studied.By analyzing the effect of network induced delay on the system,a time delay system model is established.On the basis of the model,the criterion of system norm bounded stability is obtained by Lyapunov stability theorem and linear matrix Inequality(LMI),the joint design of event-triggered parameters and feedback control gain is carried out by the described form of linear matrix inequalities.The simulation results show that the event-triggered mechanism can significantly reduce the data transmission and save the network resources effectively compared to the periodic-triggered mechanism.Finally,the quantizer is introduced to quantify the sampled signal to reduce the size of the transmitted data,and the event-triggered mechanism is improved to improve the ability of event triggers to adjust the different state of the system.By establishing a system model including time-varying time delay,event trigger and quantizer,the control problem of network delay,event triggering parameter,quantizer parameter and controller gain are combined into a system,and the stability criterion which make the closed-loop system asymptotically stable and satisfy the given performance index.On this basis,the joint design method of quantizer,event trigger and controller is obtained.