Observer design and active fault tolerant control for Takagi-Sugeno systems affected by sensors faults

Abstract

This paper deals with the problem of active fault tolerant control strategy for nonlinear systems described by Takagi-Sugeno models. The proposed control law uses the estimated fault. The considered systems are affected by sensor faults. A mathematical transformation is used in order to conceive an augmented system in which the sensor faults affecting the initial system appear as unknown inputs. A proportional integral observer with unknown inputs is conceived in order to estimate simultaneously states and sensor faults. The stability of the system with the proposed fault tolerant control strategy is formulated using Lyapunov theory and the observer gains are obtained by solving linear matrices inequalities. To illustrate the proposed method, it is applied to the three columns.