Enhancing Resilience of Islanded Microgrids Under Disturbances, Delays, and DoS Attacks Through a Novel Digital...

Since distributed control theory has now become a key ingredient in modern cyber-physical microgrids (MG), its implementation is inseparable from data communication. The introduction of a communication infrastructure inevitably brings communication threats, such as denial-of-service (DoS) attacks and network induced delays. This article represents the first attempt toward a unified distributed digital predictor-based control scheme for the solution of the secondary voltage restoration problem in islanded MGs, which also involves external unknown disturbances and network vulnerabilities, thus enhancing its resilience and reliability. The novel sampled-data predictive controller revises the conventional model reduction approach to reformulate it in a fully distributed digital way and involves some external disturbances information for prediction performance improvement, even though these perturbations are completely unknown. The main features of the resulting method are: 1) large delays compensation accounting for networked-induced delays and sleeping time interval due to DoS attacks occurrence and 2) unknown disturbance attenuation, usually neglected in the controllers synthesis phase in MGs field. Lyapunov-Krasovskii theory is exploited to analytically prove the exponential stability of the MG voltage, thus leading to linear matrix inequality-based sufficient stability conditions. Numerical and experimental results confirm theoretical derivations.