Summary
2007 International Symposium on Nonlinear Theory and its Applications
2007
Session Number:19PM1-A
Session:
Number:19PM1-A-4
Nonlinear Dynamics of a Flexible Rotor in Active Magnetic Bearings
Jawaid I. Inayat-Hussain,
pp.481-484
Publication Date:2007/9/16
Online ISSN:2188-5079
DOI:10.34385/proc.41.19PM1-A-4
Summary:
This work reports on a numerical investigation on the nonlinear dynamics of a flexible rotor in active magnetic bearings. The mathematical model of the flexible rotor - active magnetic bearing system used in this study incorporates nonlinearity arising from the magnetic actuator forces that are nonlinear functions of the coil current and the air gap between the rotor and the stator, and from the geometric coupling of the magnetic actuators. The response of the rotor, with the variation of the speed parameter, Ω , displayed a rich variety of nonlinear dynamical behaviour including subsynchronous vibrations of periods-3, -6 and -9, quasiperiodicity and chaos. Such vibrations in the operation of rotating machinery is undesirable and should be avoided as they introduce cyclic stresses in the rotor, which in turn may rapidly induce fatigue failure.