False Data Injection Attacks Against Cyber-physical Power Systems And Countermeasures

Modern power systems have developed into a complex cyber-physical system composed of electric power and its monitoring systems,facing more and more serious cyber-physical security problems.And false data injection attack is one of the most important forms of cyber-physical security problems.Research of false data injection attack and its countermeasures is vital to ensure the safety,stability and economic of power systems.In this paper,the false data injection attack strategies under AC state estimation and the countermeasures considering the system topology change are studied,and the main work is as follows:(1)The general form of false data injection attack strategy model is proposed.The general form of false data injection attack is extracted by analysing the basic requirements of false data injection,the target of attackers and different attack scenarios.The general form can provide an unified guide to the subsequent building of the attack strategy model for AC systems and Voltage Source Converter based High-Voltage Direct Current(VSC-HVDC)transmission systems in different attack scenarios,and also the solving of attack strategy models.(2)A method to solve the strategy model of false data injection attacks under AC state estimation is proposed.Based on the state analysis of the system,a method of solving the strategy model of the false data injection attacks under AC state estimation is proposed.By simulation analysis of the false data injection attack of the AC system under two kinds of attack scenarios and that of VSC-HVDC systems with the target of destroying the operation security of converters,the correctness and effectiveness of the proposed model and solving method are illustrated.(3)The characteristics of false data injection attack under AC state estimation are analyzed.With two typical false data injection attack scenarios of AC systems,the impact of false data injection attacks on the maximum standard residuals of state estimation,the attack success rate,the number of measurements needing to tamper and the influence of measurement redundancy on the attack are analyzed.(4)The false data injection attack problem facing VSC-HVDC systems is revealed unprecedentedly.We present a false data injection attack strategy model aiming at destroying the operation security of VSC-HVDC systems,and then reveals that the false data injection attack can make the VSC-HVDC system operate for a long time outside the secure operatiting interval,thus causing converters suffering from over voltage and over current.(5)An optimal robust active defense strategy against false data injection attacks is proposed.Considering that the existing protection-based false data injection attack defence strategies do not account for power system topology changes,an optimal robust active defense strategy is proposed.And then combining graph theory and recursive Bayesian estimation,the optimal robust active defense strategy model is solved from the standpoint of pattern recognition.