Fuzzy Logic in Active Magnetic Bearing Control

Active magnetic bearings are special bearings for demanding applications. With modem hardware and sophisticated control methods the problems, that arise from the nonlinear structure of the active magnetic bearing system, can be overcome. In this paper a fuzzy derivate gain adjusting method for active magnetic bearing control is presented. The method is based on the error and error derivate signals that are used as the basis of the fuzzy inference. With this method the effects of the vibration noise can be decreased. To achieve adequately high sampling rate for the control algorithm a powerful digital signal processor (DSP) was used in the experiments.