Abstract
In this paper, we study detection problem of replay attacks on smart grid. A smart grid is operated as if it is a Cyber-Physical System with solid links between its calculation and its material constituents, hence ensuring cyber security has been an important role. The goal of this paper is to detect replay attack that is one of cyber attacks on the sensors of a control system. We propose a detecting method adding intentional noise to not only sensors as code signal but also input. Replay attack can immediately be reflected by using fault diagnosis matrices that are composed of the estimator and observed values even if code signal is decrypted. Finally, we show simulation results to analyze effectiveness of the proposed method.
