2020 journal article

H-infinity observer-controller synthesis approach in low frequency for T-S fuzzy systems

IET CONTROL THEORY AND APPLICATIONS, 14(5), 738–749.

By: W. Xie*, Z. Han*, F. Wu n & S. Zhu*

co-author countries: China 🇨🇳 United States of America 🇺🇸
author keywords: convex programming; observers; linear matrix inequalities; robust control; feedback; fuzzy systems; eigenvalues and eigenfunctions; control system synthesis; fuzzy control; continuous time systems; Lipschitz conditions; system stability conditions; eigenvalues; generalised Kalman-Yakubovich-Popov lemma; robustness conditions; output feedback control problem; continuous-time T-S fuzzy systems; H infinity observer-controller design method; H infinity observer-controller synthesis approach; linear matrix inequality forms; convex optimisation technique
Source: Web Of Science
Added: April 6, 2020

For the output feedback control problem of continuous-time T–S fuzzy systems with unknown premise variables, an observer–controller design method in the low-frequency domain is proposed. First, an observer–controller structure is given, the unknown premise variables are limited by Lipschitz conditions. Then, the system stability conditions are obtained by the negativeness of eigenvalues' real parts. To achieve better control performance of the system in low frequency, the index for attenuating the unknown low-frequency disturbance is guaranteed by generalised Kalman–Yakubovich–Popov lemma. Then, the stability and robustness conditions are converted into linear matrix inequality forms, which can be solved directly by a convex optimisation technique. Finally, several simulation examples carried out to show the effectiveness of the proposed method.