Finite-Time Attack Detection and Secure State Estimation for Cyber-Physical Systems

Dear Editor, This letter aims to investigate the problem of attack detection and state estimation when the system suffers from external malicious attacks. A finite-time reduce-order observer is designed, which can achieve attack detection at the preset time instant. Meanwhile, it is shown that the protection of the key nodes greatly improves the efficiency of secure state estimation. Finally, the proposed theory is applied to a general cyber-physical system to illustrate its effectiveness.