On local H-infinity switched controller design for uncertain T-S fuzzy systems subject to actuator saturation with unknown membership functions

Author(s)

de Oliveira, Diogo Ramalho ^{[1, 2]} ; Minhoto Teixeira, Marcelo Carvalho ^[1] ; Lendzion Tomaz Alves, Uiliam Nelson ^[3] ; de Souza, Wallysonn Alves ^[4] ; Assuncao, Edvaldo ^[1] ; Cardim, Rodrigo ^[1]

Affiliation

^[1] Sao Paulo State Univ UNESP, Dept Elect Engn, Campus Ilha Solteira, BR-15385000 Ilha Solteira, SP - Brazil

^[2] IFMS Fed Inst Educ Sci & Technol Mato Grosso do S, Campus Tres Lagoas, BR-79641162 Tres Lagoas, MS - Brazil

^[3] IFPR Fed Inst Educ Sci & Technol Parana, Campus Jacarezinho, BR-86400000 Jacarezinho, PR - Brazil

^[4] IFTO Fed Inst Educ Sci & Technol Tocantins, Dept Math & Nat Sci, Campus Palmas, BR-77021090 Palmas, TO - Brazil

• Document type: Journal article
• Source: FUZZY SETS AND SYSTEMS; v. 344, p. 1-26, AUG 1 2018.
• Web of Science Citations: 2

Abstract

This manuscript proposes a local H-infinity switched controller design for a class of uncertain nonlinear plants described by Takagi- Sugeno (T-S) fuzzy models with unknown membership functions. The control design requires only the lower and upper bounds of the system nonlinearities and of the system linear parameters, which can depend on uncertain parameters. The switched control law chooses a state-feedback controller gain, which belongs to a given set of gains, that minimizes the time derivative of a quadratic Lyapunov function. This procedure eliminates the necessity of finding the membership function expressions to implement the control law, guarantees an H-infinity performance and ensures that the state trajectory remains within a region in which the T-S fuzzy model is valid. Due to the H-infinity control design, that frequently results in very large control inputs, it is considered that the switched control law is subject to actuator saturation. Finally, two examples are presented. The first example studies the control of a chaotic Lorenz system. It shows that, for disturbances with large magnitude, the proposed procedures provided better results than the obtained with another recent method found in the literature, that considers full access to the membership functions. In the second example, a practical implementation of an active nonlinear suspension control system, considering an uncertain bounded mass and a fault in the actuator, confirms the effectiveness of the proposed approach. (C) 2017 Elsevier B.V. All rights reserved. (AU)

• FAPESP's process: 11/17610-0 - Monitoring and control of dynamic systems subject to faults
• Grantee: Roberto Kawakami Harrop Galvão
• Support Opportunities: Research Projects - Thematic Grants