Research On The Stability Of Networked Feedback System For Deception Attacks

Networked feedback systems are closed-loop distributed system that uses a real-time network to connect control elements such as controlled objects,sensors,actuators,and controllers,and coordinates operation over a wide area through wired and wireless links.Each component of the networked feedback system can be modularized and independently designed.The system is maintained by detecting and diagnosing each module,thereby reducing the cost of fault diagnosis.In addition,the networked feedback system is superior to the traditional feedback system,which has the advantages of flexible structure and easy installation.With the development of digital communication technology,networked feedback system has been widely used in various scenarios such as smart grid,intelligent manufacturing system,modern transportation system,multi-agent system,remote control and teleoperation system.Introducing network into feedback system is also the development trend of current feedback system.On the one hand,due to the strong openness of the communication network,the network feedback system is vulnerable to the intrusion of external malicious cyber-attacks,especially the deception attacks with strong concealment,which leads to the problem of system stability.On the other hand,due to the limited network communication resources,it usually leads to network channel congestion,communication constraints,multi-packet transmission and packet loss.In addition,in the networked feedback system,data packets are transmitted through the communication network in the form of digital signals,which means that data from the controlled object needs to be sampled and quantified before transmission.Therefore,this paper focuses on the stability of the network feedback system from external malicious deception attacks and the improvement of the utilization of network communication resources.The adaptive eventtriggering mechanism(AETM),which is highly adaptive to the dynamic feedback system,is adopted.Combined with Lyapunov function method and linear matrix inequalities(LMIs)technology,the corresponding solutions are obtained.The main research work is summarized as follows:(1)The problem of mean square stability analysis and controller design for networked feedback systems subjected to stochastic nonlinear deception attacks is discussed.Considering the influence of limited network resources and random nonlinear deception attacks,an adaptive event generator is set up between the controlled physical object and the network channel,and data sampling and transmission are carried out under this filtering mechanism.In order to make the constructed model closer to the real situation,the Bernoulli distributed variables are used to describe the occurrence of deception attacks.Based on the established system model,the Lyapunov-Krasovskii function is designed,and the sufficient conditions for the mean square stability of the system and the corresponding controller parameters are obtained.(2)The stochastic stability problem of networked feedback systems with nonlinear perturbations subjected to deception attacks under an adaptive event-triggering mechanism with saturation constraints is investigated.Considering the influence of external nonlinear disturbance input and the deception attacks of malicious injection outside the system,a new model based on adaptive event is constructed.Whether the data collected by all sensors is transmitted to the network channel is determined by the trigger scheme.Based on the proposed model,a suitable Lyapunov-Krasovskii function is constructed.Finally,sufficient conditions for the stability of the closed-loop network feedback system and the desired controller gain are given by using LMIs technology.(3)The problem of stochastic stability and state feedback controller design for networked feedback systems with parameter uncertainties under deception attacks and nonlinear disturbances is analyzed.In order to ensure the comprehensiveness of the sampled signal,a zero-order holder is added to the control structure to convert the discrete sampled signal into a continuous signal.The adaptive triggering scheme is applied to the uncertain networked feedback system,which saves a lot of network communication resources.By transforming the nonlinear matrix inequalities with parameter uncertainty into LMIs that can be solved,the sufficient conditions for the stochastic stability of the uncertain networked feedback system are obtained.