Design of Attack-Resilient Load Frequency Control for Hybrid Wind–Diesel Power Systems Under Hybrid Cyber Attacks

This paper investigates the finite-time boundedness problem of hybrid wind–diesel power systems through an attack-resilient load frequency control framework in the presence of hybrid cyber attacks and multiple disturbances. The considered disturbances include matched disturbances and mismatched disturbances. To address these challenges, an output-reliant disturbance observer is developed to accurately estimate the matched disturbances, while a dissipative mechanism is employed to attenuate the effects of mismatched disturbances. By utilizing the disturbance estimates and the measured system output, a proportional–integral observer is constructed to estimate the system states. Subsequently, an attack-resilient load frequency controller is designed based on the estimated states and disturbances. Furthermore, multimodal false-data-injection and replay attacks are incorporated into the controller channel to realistically model hybrid cyber threats and enhance controller resilience. Based on Lyapunov stability theory and finite-time stability concepts, sufficient stability conditions are derived in terms of linear matrix inequalities to guarantee finite-time boundedness of the closed-loop system. These conditions also provide a systematic approach for computing the observer and controller gain matrices. Finally, simulation results are presented to demonstrate the effectiveness and robustness of the developed control scheme under hybrid cyber attacks and multiple disturbances.