Non-Fragile Robust Security Control Based on Dynamic Threshold Cryptographic Detector for Remote Motor under Stealthy FDI Attacks

This paper investigates a non-fragile robust security control strategy for remote motors, based on a dynamic threshold cryptographic detector. This strategy aims to protect system performance against stealthy false data injection (FDI) attacks and to effectively minimize the impact of controller jitter. First, a stealthy FDI attack is designed to bypass the conventional χ2 detector and degrade system performance. The stealthiness and destructiveness of the attack are demonstrated. Next, to counter the stealthy FDI attack, a dynamic threshold cryptographic detector is proposed. This detector addresses the stealthiness of the attack and enhances robustness by incorporating a time-varying nonlinear function and a dynamic threshold detection strategy. Furthermore, a non-fragile robust security control strategy is introduced to prevent these attacks and mitigate the problem of controller perturbations. The stability of this strategy is proven using Lyapunov theory. Finally, the effectiveness of the proposed security control strategy is validated through numerical and semi-physical simulations.