Resilient Event-Triggered Observer-Based Periodic Wide-Area Control for Oscillation Damping in WAMPAC Systems Under Time Synchronization Attacks

In this article, we address the problem of delay-causing time synchronization (DC-TS) attacks against wide-area damping controllers (WADCs). To enhance smart grid stability against such threats, we present a realistic and secure design procedure for WADCs. To this end, we follow a methodology that utilizes the state-space model of the entire grid to design a periodic observer-based event-triggered controller by formulating the problem as a set of linear matrix inequalities, solved by the looped-Lyapunov functional (LLF) technique. The event-triggered scheme applied in this design procedure improves communication efficiency. Plus, the periodic sampled-data approach makes the design better suited to the operational reality of digital systems and their constraints. As such, the contributions of this work include developing an event-triggered mechanism to reduce unnecessary data transmissions, applying LLF for less conservative stability analysis, and utilizing the Guardian map theorem and Rekasius substitution to assess the WADCs resilience under DC-TS attacks. We conducted extensive simulations on the Kundur two-area and New England 39-bus systems to validate our approach. These simulations, along with comparisons to existing methods and tests on the RT-Lab real-time platform, demonstrate the superior performance of our WADC in maintaining grid stability and improving damping under considered attacks.