Pseudo-equivalence of fuzzy PI controller

This paper presents a pseudo-equivalence of the digital PI fuzzy controllers with the PI linear controllers in the continuous time domain. A method to design PI fuzzy controller is presented. Transfer functions and equivalence relations between controller's parameters are obtained for the common structures of the PI fuzzy controllers. The pseudo-equivalence is made based on a grapho-analithic analysis based on transfe characteristics of the fuzzy block, the linearization of the fuzzy block around the origin and the usage of the gain in origin obtained as an origin limit of the nonlinear gain of the fuzzy block. An algorithm of equivalence presented. Some advantages of this method are emphasized.