On a Takagi-Sugeno Fuzzy Controller with Non-Homogenous Dynamics

Abstract

The paper proposes a Takagi-Sugeno fuzzy controller with non-homogenous controller dynamics with respect to the two input channels, that means, in the linear case, different transfer functions with respect to the reference input and to the controlled output. The considered controller is dedicated to a class of third-order integral-type plants, specific to the field of electrical drives, which can be characterised in their simplified linearised forms by standard models. For these models even conventional linear control structures give satisfaction. There is proposed a development method for the fuzzy controller, based on the fact that fuzzy controllers can be, in some certain conditions, well approximated by linear controllers and, so, the Extended Symmetrical Optimum (ESO) method and the Modified Structure of ESO Method are applicable in this situation. The fuzzy controller and its corresponding development method are validated by an application example that can correspond to the speed control of an electrical drive.