Tuning of 2-DOF fuzzy PI(D) controllers. Laboratory applications

The paper presents aspects concerning the tuning of two-degree-of-freedom (2-DOF) fuzzy controllers focused on 2-DOF PI-fuzzy controllers and on 2-DOF PID-fuzzy controllers. 2-DOF Mamdani and Takagi-Sugeno fuzzy control system structures are offered. The tuning is based on mapping the parameters of the linear PI and PID controllers to the parameters of the fuzzy controllers in terms of the modal equivalence principle. The linear controllers are tuned by Preitl's and Precup's Extended Symmetrical Optimum method. Some experimental results dealing with the speed control of a servo system are given.