Secure State Estimation Against FDI Attacks and Unknown Disturbances: A Descriptor Reduced-Order Observer Method
Qingdong Sun, Guang‐Hong Yang · IEEE Internet of Things Journal · 2025
This paper studies the problem of secure state estimation based on disturbance decoupling for continuous-time linear systems under FDI attacks and external disturbances, where disturbance decoupling means that the estimation errors of the designed observer are not affected by attacks and unknown disturbances. Under the assumption that partial output measurements are reliable, a necessary and sufficient condition for the solvability of the disturbance decoupling secure state estimation problem is given using the constructed augmented system. Then, according to this condition, a descriptor reduced-order observer is designed, and it is proven that the corresponding estimation errors can asymptotically converge to zeros. Finally, a practical example is presented to verify the effectiveness and superiority of the designed observer.