Research On Security Control Of Networked Systems With Hybrid Attack

Since the 21 st century,with the development of network communication technology,networked control system has been paid more and more attention and developed greatly.Due to the external environment of media and system,the network resources of networked control system are often limited,so how to solve the problem of resource limitation has been widely concerned.At the same time,in view of the openness and uncertainty of the network environment,the impact of network attacks on the system is often valued by scholars.Considering the above problems,this paper mainly studies the controller design and filtering of networked control system with resource constrained and hybrid attack.In order to solve the problem of limited network resources,this paper introduces an event triggering mechanism.Under this mechanism,the data will be transmitted only when the transmission data meets the trigger conditions,thus greatly saving the network resources.In the aspect of network security,this paper considers three kinds of common attacks: deception attack,replay attack and Do S attack,and studies the controller design and filter design of networked control system under the hybrid attack.The main contents of this paper are as follows:The first chapter introduces the research background and significance of this paper,and introduces the lemma and related symbols needed for theoretical derivation.In the second chapter,the controller design of event-triggered networked control system is studied.In this chapter,for the first time,a mathematical model of hybrid attack is established,which considers deception attack,replay attack and Do S attack at the same time.It should be noted that in this hybrid attack,deception attack and replay attack occur randomly,and Do S attack is aperiodic.At the same time,considering the impact of hybrid attacks,a new event-triggered mechanism is proposed to solve the problem of limited network resources.On this basis,a networked control system model based on event triggering under hybrid attack is established for the first time.Based on the system model,we obtain the sufficient conditions for the stability of the system and the designed controller gain matrix.At the end of this chapter,a simulation example is given to prove the effectiveness of the proposed method.In addition,the comparison with existing methods is also given.In the third chapter,we study the adaptive-event-triggered filtering problem of networked control system under hybrid attack.In order to make better use of the sampling data,we update an adaptive event-triggered mechanism based on the eventtriggered mechanism.The trigger parameter of this mechanism is no longer a fixed preset value,but a dynamic parameter satisfying the adaptive law.Such a mechanism can better meet the changing system.In this way,considering the influence of input constraints,a filter error system model based on adaptive event triggering under hybrid attack is established for the first time.Based on the system model,we obtain the sufficient conditions for the stability of the filter error system and the expression of the designed filter parameter matrix.Finally,we use two simulation examples to prove the effectiveness of the proposed method.The fourth chapter makes a summary of the research in this paper.Moreover,we analyzes the shortcomings of the research and prospects the future research direction.