| In recent years,due to the adjustment and reform of power system energy structure caused by large-scale new energy access,the interconnected microgrid technology has been vigorously developed.However,the interconnected microgrid has a large scale and complex model,showing high-dimensional nonlinear characteristics,which is difficult to model accurately.In addition,the open nature of communication network used for data transmission makes the interconnected microgrid highly vulnerable to malicious network attacks.In view of this,this paper aims to study the security control problem of DC microgrid system under network attacks from the aspects of attack types,system modeling,and stability analysis and controller design.Using the state-feedback control law and fuzzy control theory,the mathematical models of system under Denial-of-Service(DoS)attacks and DoS and False-Data-Injection(FDI)coordinated attacks are established.According to the time-varying Lyapunov function method,the relationship between the network attack parameters and DC microgrid system performance parameters is quantitatively described,and the injection current control method is proposed.The main research contents are as follows:The third chapter studies the attack parameter dependent controller design for the networked DC microgrid system under DoS attacks.Considering only the duration characteristics of the sporadic/aperiodic DoS attacks,a new type of time-constrained DoS attack model is proposed.Based on the time-constrained DoS attack model and the switching state-feedback control law,a switched DC microgrid system model under DoS attacks is established.The exponential stability criterion of DC microgrid system under aperiodic DoS attacks is derived by using the attack parameters dependent time-varying Lyapunov function method,and a resilient control method is proposed.The feasibility and superiority of the designed control method are illustrated by a specific simulation example and simulation comparisons.The fourth chapter studies the FDI attack estimation and resilient control of DC microgrid under DoS and FDI coordinated attacks.Considering the time-constrained DoS attack model,pulse observer and switching state-feedback control law,a switched DC microgrid system model under DoS and FDI coordinated attacks is established.The exponential stability condition of the system is given by using the attack parameter dependent time-varying Lyapunov function method,and a joint design method of the state-feedback controller and the FDI attack observer is proposed.The feasibility of the proposed scheme is verified by simulation research.The fifth chapter studies the fuzzy controller design of DC microgrid based on T-S fuzzy model under DoS attacks.Considering the non-uniform time scale and parallel distributed compensation fuzzy control rules in the networked T-S fuzzy model,a T-S fuzzy model of the DC microgrid system is established.Then,based on the time-constrained DoS attack model and the switching state-feedback control law,a T-S fuzzy system model of the switching DC microgrid under DoS attacks is established.The exponential stability criterion of the system is given by using the time-varying Lyapunov function method,and a fuzzy control strategy is designed.The effectiveness of the strategy is verified by a simulation example. |
