Control Synthesis Of Event-triggered Mechanism Based Networked Control System In Several Network Environments

In recent years,due to the continuous innovation of network communication technology,networked control system has made great progress.However,transmission of control signals through the network also brings many problems such as communication delay,packet losses and so on.These problems bring many challenges to the system analysis and synthesis.The current driving mode mainly includes time-triggered mode and event-triggered mode.Time-triggered control,which requires frequent signal communication,will lead to the network resources wasting,system energy consumption increasing and the impact of network environment factors on system performance highlighting.In contrast,the widely concerned event-triggered control can be implemented according to the demand of the state of plant,which can effectively save system resources.Based on the aforementioned analysis,and considering the influence of several network environment factors,this paper aims to investigate the following contents:(1)Considering the non-ideal network environment with time-varying delay,the problems of stability analysis and controller design for event-triggered communication mechanism based networked control systems are studied.By taking the advantages of state error dependent and independent event-triggered mechanism into full consideration,a novel periodic event-triggered communication scheme is proposed,which can reduce the data communication rate obviously.Based on the new established novel Lyapunov functional,an asymptotic stability criterion for the closed-loop system is proposed and the stability controller design method is given.As the simulation results shows,the new proposed control scheme can save system resources effectively.(2)Considering the impact of time delay and disturbance,the problem of H_?control for networked control system with time-varying sampling is studied under the action of event-triggered mechanism.Assuming that the sampling period is variable,a time delay system model is established by making full use of the modeling method of time-delay system.The time delay model is closely related to event-triggered threshold parameters and time delay information.Based on the Lyapunov stability theory and LMI method,the stability criterion of control system is obtained and the feedback controller is designed.the conservatism of the system is reduced for dealing with the integral terms by using Jensen inequality and free weight matrix method.Through the system simulation,the superiority and effectiveness of the proposed scheme are verified.(3)Considering the time delay and disturbances in the system,the dynamic output feedback controller co-design problem for networked control system is studied under the action of event-triggered mechanism.In order to reduce the data communication rate,a periodic event-triggered communication scheme is presented.Then,a time delay system model with event-triggered threshold parameters,network-induced delay information and controller gain matrices is established.Based on Lyapunov stability theory and Wirtinger inequality method,a closed-loop system asymptotic stability theorem is proposed,and a co-design method of event-triggered threshold parameter and dynamic output feedback controller is presented.The feasibility of the scheme is verified by simulation example.