EXPERIMENT BASED ON FUZZY LOGIC CONTROL FOR ACTIVE MAGNETIC BEARING SYSTEM

Abstract

This study presents an intelligent control method for positioning a non-linear active magnetic bearing (AMB) system by using an emergent fuzzy logic controller (FLC). In this work, an AMB system that supports a rotating shaft without a physical contact is presented. By using a rotor dynamic model of the AMB system and electromagnetic forces of magnetic bearing the author designed an FLC for the AMB system. A closed-loop decentralized FLC for the AMB system was designed in this study. The control algorithm was numerically evaluated to construct a multiple-input and multiple-output mathematical model of the controlled system. The membership functions and rule design of FLC were based on the mathematical model of the AMB system. A current amplifier and hardware-in-loop (HIL) were used for an electromagnetic coil to generate magnetic forces suspending the rotor in the magnetic bearing. The results indicated that the system exhibits a satisfactory control performance with a low overshooting and produc-es improved transient and steady-state responses under various operating conditions. The proposed con-troller can be feasibly applied to AMB systems exposed to various external disturbances.