Distributed robust attack detection and reconstruction for a class of uncertain nonlinear interconnected CPSs

Abstract

In this paper, we consider distributed attack detection and reconstruction problem for a class of uncertain nonlinear interconnected cyber-physical systems (CPSs). Detectability conditions of existing attacks are investigated in a nominal form firstly. Subsequently distributed robust descriptor observers with neural network approximation of uncertainties are proposed to estimate the state and attack simultaneously, and residuals signal together with attack detection logics are also presented. Theoretical analysis shows that, under certain conditions, the proposed scheme can approach the state and attack with ultimately uniformly bounded errors, and neural network parameters are also bounded and converge into the neighbor of the ideal ones. Furthermore, attacks are ensured to be detected with the residual signal together with the attack detection logic robustly. Finally, the results are applied to a two-generator infinite bus power system under attack, which verifies the effectiveness and validness of the proposed distributed robust schemes.