Resilient Adaptive Event-Triggered Control of Nonlinear DC-Microgrids Under DoS Attacks: Local Stabilization Approach

Abstract

This paper tackles the challenge of local stabilization control in nonlinear DC-microgrids (DC-MGs) under the threat of energy-constrained Denial-of-Service (DoS) attacks, using a dynamic resilient event-triggered mechanism (DRETM) and a fuzzy-basis-dependent Lyapunov approach. In contrast to previous studies, this paper introduces the operating range of system states, given when transforming the nonlinear DC-MG system into a Takagi-Sugeno (T-S) fuzzy model, as a pivotal constraint, aiming to prevent undesired system behaviors. Moreover, as part of an initial effort to analyze the impact of both DoS attacks and event-driven data transfer schemes on the local stabilization problem, this paper exploits the features of energy-limited DoS attacks and DRETM when deriving necessary conditions to ensure the local operation of the system state. Especially, to enhance the efficiency of the proposed method while minimizing conservatism and computational complexity, this paper eliminates certain unnecessary state constraints typically required when dealing with a closed operating range. Lastly, the validity of the proposed method is illustrated through two numerical examples. Note to Practitioners—As is widely recognized, the T-S fuzzy model has been extensively employed for efficiently capturing the nonlinear dynamics of DC-MG. However, the limitations of prior studies lie in their adherence to the system operating range assumption, rendering their findings unable to ensure the stability of the closed-loop system when this assumption is violated. To address this issue, this paper introduces a local stabilization control approach within the fuzzy-based Lyapunov function framework. This approach plays a crucial role in eliminating the need for operating range assumptions and achieving less conservative results. As a result, practitioners can now confidently utilize our improved approach to effectively stabilize nonlinear DC-MGs without the risks of unexpected behaviors. In addition, this paper confronts the task of devising an event-triggered controller while taking into account energy-limited DoS attacks and resource wastage in DC-MGs, such that: 1) the state trajectory of DC-MG T-S fuzzy systems remains in the operating region regardless of energy-limited DoS attacks, and 2) eventually converges to the equilibrium point without requiring any prior information about DoS attacks. Finally, two numerical examples demonstrate the validity of the proposed method.