Resilient Synchronization of Voltage/Frequency in AC Microgrids Under Deception Attacks

This article proposes a resilient distributed secondary voltage and frequency control scheme for autonomous ac microgrids considering disturbances and attacks on both sensors and actuators. To achieve the main objectives of the control system, first, a distributed state observer is employed to predict the normal behavior of state variables in the presence of potential deception attacks. Then, a distributed H-infinity controller is utilized to mitigate the impacts of disturbances and uncertainties. Finally, to overcome the detrimental effects of attack signals, a resilient distributed adaptive algorithm is integrated with the designed H-infinity controller. The proposed control algorithm has no restriction on the number of agents under attack and guarantees the boundedness of synchronization errors for all units. Also, in addition to distributed generation units, the contribution of distributed energy storage (DES) units in the regulation of voltage, frequency, and active power sharing is considered. Due to the limited energy of DESs, it is needed to balance the state of charge of these units. We evaluate the performance of the proposed algorithm using offline digital time-domain simulation studies carried out on a test microgrid system in MATLAB/Simulink environment, and the results are compared with previously reported methods. Simulation results and comparison with previous works reveal the effectiveness and accuracy of the proposed algorithm in regulating microgrid voltage and frequency.