Security Analysis And Evaluation Method Of Distribution Network Cyber Physical System(CPS) For Network Attack

With the rapid development of ICT technology and automation control technology,the distribution network has gradually transformed into a distribution network information physical system(distribution network CPS)with highly coupled information systems and physical systems.The information system supports the stable operation of the physical system,and it also brings certain security risks to the distribution network CPS.For example,there are attack methods such as network attacks that attack information systems,which cause the failure of power services or functions and affect the safe and stable operation of the distribution network CPS.Therefore,in the context of the distribution network CPS,it is necessary to take an effective and reasonable method to evaluate safety.Based on the above background,this paper studies the issues of modeling techniques for distribution network CPS,the mechanism of network attack risk propagation,system security assessment under network attacks,and the CPS security defense methods of distribution network.The main technical contributions include the following aspects:(1)Distribution network CPS modeling technology based on association matrix.This paper adopts the correlation matrix-based modeling technology to accurately model the hierarchical structure of the distribution network CPS,and associates the physical entity layer,the information physical coupling layer,and the information system layer to form a complete distribution network CPS unit model..The establishment of the distribution network CPS correlation matrix model can clearly represent the interaction between information and physics in the distribution network CPS,and provides a model basis for subsequent security research.(2)Information-physical combinations for anticipated fault screening considering network attacks and considering the impact of information during the recovery process distribution network CPS security assessment.This paper proposes a method for filtering the expected physical failure of the distribution network CPS information physical combination considering network attacks.Based on the role of the network attack in different locations of the information system,it is summarized and modeled and combined with physical failures.A screening basis is proposed,which can effectively and reasonably screen out key information physical combination faults.The impact of the information system during the fault recovery process is analyzed,and a distribution network CPS security assessment method is proposed.(3)Design of distribution network CPS information physical security defense scheme.Based on the security defense concept of large power grids,this paper designs a distribution network CPS information physical security defense scheme.From the information side and the physical side,according to different control stages,it proposes a distribution network CPS information physical prevention control,emergency control,and recovery control scheme.