Robust load-frequency control for uncertain nonlinear power systems: A fuzzy logic approach

A new robust load-frequency control (LFC) methodology is proposed for controlling uncertain nonlinear power systems. Critical nonlinearity in the power system—the valve position limit on the governor, and the parametric uncertainty are concerned. The Takagi–Sugeno fuzzy model of the power system under consideration is first constructed to design the robust fuzzy-model-based LFC. Sufficient conditions for the robust asymptotic convergence of the frequency deviation are then provided in terms of linear matrix inequalities. Boundedness of the other system variables is also studied to ensure justifiable grounds for use of the proposed LFC method. Simulation results convincingly validate the effectiveness of the novel LFC design scheme and the theoretical discussions, which give a positive answer to the quality control of the electric energy. 2006 Elsevier Inc. All rights reserved. 0020-0255/$ see front matter 2006 Elsevier Inc. All rights reserved. doi:10.1016/j.ins.2006.01.003 * Corresponding author. Tel.: +82 2 2123 2773; fax: +82 2 362 4539. E-mail addresses: [email protected] (H.J. Lee), [email protected] (J.B. Park), [email protected] (Y.H. Joo). H.J. Lee et al. / Information Sciences 176 (2006) 3520–3537 3521