Research On Multi-area Power System Load Frequency Control Under Cyber-attacks

Load frequency control(LFC)is an effective technology of regulating frequency in multi-area power systems,which ensures frequency stability by controlling the active power of generators within each area.In recent years,with the widespread application of new smart devices and network communication technologies,malicious cyber-attacks on multi-area load frequency control systems have become increasingly common,which bring serious challenges to the security of the system.Therefore,maintaining frequency stability of multi-area load frequency control systems under cyber-attacks is of great research significance.To ensure the frequency control performance of LFC systems under cyber-attacks,this paper achieved the following three research results from four aspects: system modeling,attack types,system stability analysis,and controller design.1.The security control problem of multi-area LFC systems under denial-of-service(DoS)attacks is studied.First,based on periodic DoS attack model and switching system model,a switching multi-area LFC system model under DoS attack is established.Second,the attack-parameter-dependent time-varying Lyapunov function method is used to analyze the exponential stability of the system and quantitatively characterize the relationship between cyber-attack parameters and system performance.Then,according to linear matrix inequality(LMI)technology,a design scheme for the system controller is provided.Finally,the effectiveness of the proposed approach is verified through numerical simulation experiments.2.The security control problem of multi-area LFC systems under both DoS and false data injection(FDI)attacks.Firstly,a hybrid attack model and FDI attack observer model are established based on periodic DoS attack model and FDI attack model.Secondly,the stability of the system is analyzed based on the attack-parameters-dependent time-varying Lyapunov function method.Then,a co-design scheme for controller and attack observer is proposed based on LMIs technology.Finally,the effectiveness of the proposed scheme is verified through simulation experiments.3.The security control problem of event-triggered multi-area LFC systems under both DoS and FDI attacks.Firstly,a hybrid attack model is established based on DoS attack model and FDI attack model.Secondly,a state observer is constructed based on system output information to obtain the system state vector.Then,a static event-triggering mechanism is introduced to reduce the system communication load.According to the attack model,observer model,and event-triggering mechanism,the attack-parameters-dependent time-varying Lyapunov function method and LMIs technology are used to provide the conditions for the exponential stability of the system,and a co-design scheme of state observer and FDI attack observer and attack compensation controller is proposed.Finally,the effectiveness of the proposed scheme is verified through simulation experiments.