Co-design Of Security & Safety Control And Communication For ICPS With Attack And Fault

Cyber-Physical System(CPS)is a new generation of intelligent system integrating sensing,computing,control and network communication.Due to its advantages of structural networking,functional modularization and intelligent control,CPS has been widely used in various field.Industry Cyber-Physical System(ICPS),which generated by the integration of CPS and industrial control,has become the preferred architecture of industry control systems.However,ICPS also faces many problems to be solved during its development,such as:with the industry network from relatively closed to more open,network security issues become particularly prominent;Compared with the traditional industry control system,although ICPS has a higher level of networking,digitalization and intelligence,its working environment is still relatively bad,and the physical faults cannot be ignored.In addition,the strong data sensing ability of ICPS makes terminal equipment transmit more data through the network,and the contradiction between the limited network resources also has become increasingly prominent,and so on.However,the methods that can effectively solve the above problems are still limited.So this thesis will focus on the false data injection(FDI)attack with strong time and space stealthy and great harm and the actuator failure in terrible environments.Under the Discrete Event-Triggered Communication Scheme(DETCS),the following security&safety control research on ICPS is carried out.1)For the ICPS with both FDI attacks and actuator faults,firstly,through consideration of all of the factors such as calculation,reasonable allocation and efficient utilization of communication resources,and easy implementation of attack defense strategies,a security&safety control framework of ICPS is constructed under the DETCS;Secondly,a robust H? estimator is designed to achieve accurate estimation of system state,actuator fault and bilateral network FDI attacks;Then,based on the estimated results,a security&safety control strategy is designed,which utilizes separation and compensation for FDI attacks in bilateral networks and compensation for actuator faults.At the same time,combined with Event-Triggered conditions,a co-design method of security&safety control and communication is given.Finally,the effectiveness of the proposed method is verified by a numerical and quadruple-tank example.2)Taking into account the actual industrial control,while ensuring the safety and resist disturbance of ICPS,it is also expected to have satisfied dynamic performance.Further,the co-design of ICPS security&safety control and communication under multi-objective constraints is studied.By introducing the concept of ?stability,a robust H? estimator with ?1-stability and security&safety control and communication co-design method with ?2-stability are given respectively.During proof of the theorem,considering the conservativeness of parameter setting method in dealing with nonlinear matrix inequality(NLMI)and the reduction of solution space under multi-objective constraints,a cone complementarity linearization(CCL)algorithm with less conservativeness is adopted to increase the solution space and improve the control performance of ICPS.The simulation results show that the robust H? estimator and security&safety controller designed by combining multi-objective constraints with CCL algorithm make ICPS have better dynamic performance while working safely.3)Further consider the more conceal FDI attacks.First,the implementation process of conceal FDI attacks is analyzed in depth from the attacker's perspective,and a description of the nonlinear conceal FDI attack model that depends on the output of the system and the bounding conditions that it meets is given;Secondly,comprehensively considering the computing power of edge smart devices and effective defense strategies against hidden FDI attacks,under DETCS,a security&safty control framework of ICPS was reconstructed;then,for ICPS with non-linear conceal FDI attacks,through introducing a robust sliding mode observer in the intelligent sensing unit,the state,conceal FDI attack,and actuator fault estimation methods are respectively given;In addition,a security&safty control strategy based on estimation and compensation,and combined with event trigger conditions,the co-design method of control and communication is given,Finally,the effectiveness of the proposed method is verified by simulation experiments,and the results show that under the nonlinear conceal FDI attack,the sliding mode observer can get more accurate estimation results,so it is beneficial to improve the security&safty control level.