Research On Defense Strategy Of Microgrid With The Consideration Of Coordinated Cyber-physical Attack

Microgrid is a new power supply method at the end of distribution network,which can effectively absorb intermittent and distributed power generation output and improve the reliability of power supply.In recent years,advanced sensing,computing,communication and control technologies have been applied in microgrid systems.However,while information technology promotes efficient utilization of microgrid power resources and scientific energy management,security vulnerabilities in information equipment and communication network also make microgrid system face dual security challenges in information physics.The Defender-Attacker-Defender(DAD)model divides microgrid defense problems into three layers for modeling,which can not only effectively express the behavioral strategies of the Defender and Attacker,but also be closer to the practical application.It is the mainstream model for studying microgrid defense problems.Aiming at the resource allocation of microgrid defense under information physical attack,this paper adopts the three-layer DAD model to model and solve the optimal deployment of microgrid defense and optimal scheduling of microgrid defense.The main work of this paper is as follows:Firstly,the tri-level microgrid defense model based on robust optimization and its solution algorithm are studied.Firstly,by analyzing the process of physical attack and information attack,the basic mathematical model of physical attack and information attack is constructed,and an example is given.Then,based on the three-layer DAD model,the optimal deployment model of microgrid defense and the optimal scheduling model of microgrid defense are constructed respectively.In the defense operation stage of microgrid,combined with random planning and robust optimization,the three-tier DAD model is improved,which reduces the conservatism of defense scheme in the defense deployment stage of microgrid and achieves further optimization of the target.On this basis,considering the nonlinearity and the complexity of solving the model,the optimal deployment model and optimal planning model of microgrid defense are studied,and the steps of general Column-and-Constraint Generation(CCG)algorithm and Nested Column-and-Constraint Generation(NCCG)algorithm are given.Secondly,the optimal deployment of microgrid defense considering information physical cooperative attack is studied.In view of the characteristics of isolated microgrid CPS,the modeling and analysis of information physical cooperative attack are carried out,mainly considering the optimal allocation of microgrid defense resources,and considering the flexibility of mobile generators in the real-time scheduling stage after the attack,so as to minimize the impact of information physical cooperative attack on microgrid.The optimal deployment model of three-layer microgrid defense considering information physical cooperative attack is constructed.In order to reduce the complexity of the optimal deployment model of microgrid defense considering information physical cooperative attack under the framework of NCCG algorithm,The binary variable coding method is used to discretize the information attack variables,and the IEEE standard test set is used to construct a microgrid example.The experimental analysis of the model method is carried out,and the advantages of the proposed model and algorithm are demonstrated by comparing with the traditional method.Thirdly,the optimal scheduling problem of microgrid defense considering information physical cooperative attack is studied.In view of the characteristics of isolated microgrid CPS,considering the probability distribution information of attack resources of the attacker obtained by the defense side in the operation stage of microgrid,combined with the optimal configuration scheme of line protection equipment and fixed generator developed in the defense deployment stage of microgrid,based on stochastic programming theory and robust optimization theory,The optimal scheduling model of microgrid defense considering information physical cooperative attack is constructed.Then,the improved CCG algorithm proposed in this paper is applied to solve the problem.A microgrid example is constructed using IEEE standard test set of power system,and the studied model and algorithm are compared and analyzed.This paper summarizes the application effect,advantages and disadvantages of the optimal scheduling model of microgrid defense considering information physical cooperative attack in the research background of isolated microgrid operation stage.The research results of this paper have positive theoretical guiding significance and practical application value for energy management of barrack microgrid.