Adaptive fuzzy observer based non-quadratic control for nonlinear system subject to actuator faults and saturation

This paper provides a new non-quadratic stabilization conditions based on adaptive fuzzy observer for a class of Takagi-Sugeno (T-S) fuzzy systems subject to external disturbances and both actuator faults and saturation. Firstly, an observer based fault tolerant control (FTC) is proposed, not only to estimate both system states and actuator faults but also to compensate for the actuator faults and to stabilize the faulty system with input constraints. The saturation effect is transformed into dead-zone nonlinearity and the generalized sector bound condition is used to estimate the attraction domain. To less the conservatism of the quadratic Lyapunov technique, a proper integral structure based on the non-quadratic function is investigated. The H infinity criteria is considered and the robust stabilization conditions of the faulty closed -loop system are expressed as a linear matrix inequalities (LMIs) optimization problem. Finally, the robustness and the advantages of the proposed approach are demonstrated through a mixed CSTR and a numerical example.(c) 2023 The Franklin Institute. Published by Elsevier Inc. All rights reserved.

Automated summary

This paper proposes a new non-quadratic stabilization conditions based on adaptive fuzzy observer for a class of T-S fuzzy systems subject to external disturbances and both actuator faults and saturation. An observer based fault tolerant control (FTC) is proposed to estimate system states and actuator faults, compensate for the actuator faults, and stabilize the faulty system with input constraints. The advantages and robustness of the proposed approach are demonstrated through a mixed CSTR and a numerical example.