Vulnerability Analysis And Countermeasures Of Power CPS Under False Data Attack

With the continuous improvement of information technology,the traditional power system is gradually transformed into a power information physical system(CPS)integrated with the information physical system.Although the development of power CPS has improved the operation efficiency of power grid,the power system is also facing multi-dimensional attack risk,in which false data attack is the most typical attack mode.In order to launch false data attacks efficiently,attackers tend to inject false data into vulnerable nodes,and different forms of false data attacks may lead to different vulnerabilities of power CPS.Any attack on either side of the system will lead to cascading faults,which will bring challenges to the safe operation of the power grid.Based on the above background,the main research work of this paper is as follows:First,The structure cascading failure process and the influence of state estimation of the system under false data attack are analyzed,the vulnerability analysis method is proposed,and the node loss rate and load loss rate of the system under different false number attacks are studied.The experimental results show that the high critical attack makes the system more vulnerable,and the false data attack against voltage is more likely to lead to the convergence failure of state estimation,that is,the system is more vulnerable to voltage attack.Second,In order to study the slow speed of establishing random false data attack vector,heuristic and power measurement attack vector methods are proposed in this paper.At the same time,in order to further study the impact of false data attack on power flow characteristics,the voltage and power vulnerability indicators are proposed based on the AC power flow model,and the time required for the voltage and power vulnerable nodes to establish the attack vector and the number of damaged instruments are analyzed.The experimental results show that the proposed method takes less time and destroys fewer instruments than the traditional method;For voltage and power fragile nodes,it takes less time to establish attack vectors and destroys fewer instruments than any node.Third,According to the cascading fault of power CPS caused by false data attack,the fault coping strategies of information layer and power layer are proposed respectively.Based on the two hop neighbor algorithm,the coping strategy for information network fault is proposed,and the optimal load shedding strategy for power grid fault is proposed based on the optimal power flow model.The experimental results show that compared with the traditional Floyd algorithm,the two hop neighbor algorithm has better performance in restoring the information network,and the load shedding strategy of optimal power flow improves the speed of restoring the normal operation of power grid by 37.60%compared with the load shedding strategy of AC power flow.