Adaptive Event-Triggered Load Frequency Control for Multi-Area Power Systems Against Mixed Cyber-Attacks
Yajuan Liu, Zhihao Yuan, Dong Xu, Xiangpeng Xie, Ju H. Park
Abstract
This article proposes the adaptive event-triggered mechanism (AETM) load frequency control (LFC) problem for multi-area power systems with aperiodic denial-of-service (ADoS) and deception attacks simultaneously. An AETM that automatically adjusts the trigger threshold is developed to improve the communication efficiency during ADoS attacks. Different from existing ADoS attacks, a novel attack model is proposed, where the whole ADoS attack period is divided into four intervals, that is, rest intervals, continuous detection intervals, residual intervals, and active-attack intervals. Based on this ADoS attack model, the closed-loop system, which can be seen as a three-mode switched system by integrating time intervals, is introduced in a unified framework to handle the AETM, deception attacks and ADoS attacks. Time-varying segmented Lyapunov functions are constructed and some sufficient conditions are obtained to ensure exponential stability of closed-loop systems with <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$H_{\infty }$ </tex-math></inline-formula> index. At last, a three-area power system is tested to verify the effectiveness of the designed control scheme.