Design And Analysis Of Linear Networked Control Systems Based On Event-Triggering Mechanism

In recent years,with the continuous development and integration of digital technology,communication engineering,control science and computer technology,networked control system has become an inevitable trend in the development of integrated automation technology.Networked control system is a closed-loop distributed control system which connects sensors,controllers,actuators and other components of a system through a communication network,and it has the advantages of easy development and maintenance.However,under the condition that the bearing capacity of the network and limited communication bandwidth,it will inevitably cause data packet congestion,loss and retransmission and other bad phenomena with the increase of the control scale and the number of nodes,which leads to the decline of the control system performance or even system instability.The traditional time-triggered control mode will lead to the waste of energy and bandwidth inevitably when executing control tasks periodically.From the aspects of saving bandwidth and improving resource utilization,researches of network control systems based on event trigger mechanism have received more and more attention.Based on the event trigger mechanism,the networked control system are designed and analyzed in terms of control reliability,lower conservation and security.The specific contents include the following three aspects:First,for the network control system with time-varying delay,a more advanced event trigger algorithm is introduced to reduce the number of packets and the conservative.Compared with the traditional event triggered algorithm,a diagonal matrix with weighted parameters is added in the proposed algorithm,and each element in the matrix can be given a different weight to the state components.Thus the conservative of the system can be reduced to a certain extent because of using more useful information.In controller design,considering the possible actuator failures,a reliable controller,a reliable controller which can tolerate a degree of actuator failure is designed to ensure a more reliable and smooth operation of the system.Finally,the stability and performance of the system are further analyzed withLyapunov stability theory and linear matrix inequality technique.Secondly,the time-varying sampling control system is modeled as a state delay system,and then a more advanced event triggered algorithm is introduced based on a periodic sampling.This algorithm has certain advantages in reducing the conservativeness.At the same time,after changing different elements in the weight parameter matrix and corresponding trigger parameters,the number of data packet transmission can be better reduced in the network by using the proposed algorithm.In the stability analysis,the discrete Lyapunov-Krasovskii function is selected,which makes use of more original information in the system,thus making the system less conservative.In order to achieve the purpose of reducing conservative better,in use of Lyapunov stability theory for stability analysis,the improved Jason inequality is adopted,and the free weight matrix is added at the same time and so on.Finally,the system is simulated by linear matrix inequality tool to verify the effectiveness of the proposed scheme.Finally,the dynamic model to state space model of multi-area load frequency control system are completed.Taking into account security control issues,the periodical DoS attack is introduced and the final switch system model is established.Considering the current situation of limited bandwidth resources,a discrete event trigger mechanism is introduced to complete the control scheme design.Finally,the stability of the system is analyzed by using Lyapunov stability theory and the knowledge of linear matrix inequality.