PID plus fuzzy controller structures as a design base for industrial applications

This paper investigates the practical ways of designing effective combinati ons of classical PID controllers and emerging intelligent technologies for real-life industrial projects. It analyses the evolution of fuzzy controlle r (FC) design methodology. Based on the analysis, structures and methods th at combine both approaches are proposed and considered. The paper is not in tended to develop a mathematical theory, but to give some practical recomme ndations on replacing control by a human operator control with fuzzy contro l, and an on-line parameter tuning of FC parameters. These two main points are illustrated with two application projects, which are studied in greater detail. The first one includes the design of a FC supervising a PID contro l system in an automatic aircraft guidance system. The second project descr ibes the tuning of the scaling factors of a fuzzy PID-type controller with other fuzzy systems, used in the excitation control of a synchronous power generator connected to an infinite bus through a transmission line. (C) 200 0 Published by Elsevier Science Ltd.