A theoretical and experimental study of the forced frequency response of a nonlinear magnetic bearing system is presented. The system under investigation consists of an unload symmetric rotor that is attached to a flexible coupler at one end and is supported by a radial magnetic bearing at the other end. Identification of a mathematical model describing the dynamic response of such a nonlinear closed loop system based on the principle of harmonic balance is our main goal. We modify this traditional identification technique in order to identify this system more precisely. The frequency response of the resulting nonlinear model has been proven to be well in agreement with that of the experimental data.
JSME INTERNATIONAL JOURNAL SERIES C-MECHANICAL SYSTEMS MACHINE ELEMENTS AND MANUFACTURING