Observer-Based Dynamic Event-Triggered Robust <i>H</i> <sub>∞</sub> Control of Networked Control Systems Under DoS Attacks
Ling Huang, Jing Guo, Bing Li
Abstract
This paper designs an observer-based controller with a dynamic event-triggered strategy for networked control systems with external disturbance, system uncertainty, and unknown periodic Denial-of-Service (DoS) attacks. First, the system under DoS attacks is modeled as active subsystem and dormant subsystem by using the switching system method. The controller is built based on dynamic event-triggered sequence and observer with the hold-input method used as the control signal for DoS attacks active subsystem. An augmented system is constructed with the time delay method, and the <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> performance index of the closed-loop switched system is given. Then, using Lyapunov functional theory and some technical lemmas, the sufficient conditions for the stability of the system are given without the disturbance, and with disturbance, the sufficient conditions for the closed-loop system 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> performance index are deduced. Finally, a numerical example is given to verify the effectiveness of the theory. Through the minimum optimization problem, the <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> performance parameter is optimized to increase the disturbance suppression degree of the system.