A Decentralized Functional Observer based Optimal LFC Considering Unknown Inputs, Uncertainties and Cyber-Attacks

Abstract:

This paper proposes a novel, unknown input functional observer based optimal load frequency control approach for real world complex nonlinear power systems. In the proposed control approach, the control signal applied to each power plant is directly estimated via the well-designed functional observer. The proposed functional dynamic estimator is able to handle parametric and nonparametric uncertainties, control loop and sensor faults, unknown inputs and cyber-attacks. The observer for each power plant is decoupled from the other plants resulting in a more feasible implementation, reducing the complexity of the estimator, and improving the reliability of the proposed control system. The applicability of the proposed method is shown on IEEE 39 bus-system divided into three control areas. The effectiveness of the proposed control scheme is verified by comparing results with well-known control schemes. Tolerance of the proposed technique to unknown inputs, uncertainties, and possible cyber-attacks is verified by several simulation scenarios.

Published in: IEEE Transactions on Power Systems

Date of Publication: 13 May 2019 

DOI: 10.1109/TPWRS.2019.2916558