Non-linear oscillations of a rotor-magnetic bearing system under superharmonic resonance conditions

• Published in: International journal of non-linear mechanics Vol. 38; no. 6; pp. 829 - 835
• Main Authors: Ji, J.C, Leung, A.Y.T
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01-09-2003; Elsevier Science
• Subjects: Applied sciences; Bearings, bushings, rolling bearings; Drives; Exact sciences and technology; Fundamental areas of phenomenology (including applications); Mechanical engineering. Machine design; Non-linear response; Physics; Rotor dynamics; Rotor-magnetic bearing system; Solid mechanics; Structural and continuum mechanics; Superharmonic resonance; Vibration, mechanical wave, dynamic stability (aeroelasticity, vibration control...); Vibrations and mechanical waves; Rotor dynamics; Superharmonic resonance; Rotor-magnetic bearing system; Non-linear response; Vibration; Eccentricity; Unbalanced conditions; Superharmonic; Numerical method; Modeling; Perturbation method; Non linear oscillator; Active system; Magnetic bearing; Dynamic stability; Shaft; Resonance; Hopf bifurcation; Non linear effect; Journal bearing
• ISSN: 0020-7462; 1878-5638
• DOI: 10.1016/S0020-7462(01)00136-6

The effect of non-linear magnetic forces on the non-linear response of the shaft is examined for the case of superharmonic resonance in this paper. It is shown that the steady-state superharmonic periodic solutions lose their stability by either saddle-node or Hopf bifurcations. The system exhibits many typical characteristics of the behavior of non-linear dynamical systems such as multiple coexisting solutions, jump phenomenon, and sensitive dependence on initial conditions. The effects of the feedback gains and imbalance eccentricity on the non-linear response of the system are studied. Finally, numerical simulations are performed to verify the analytical predictions.