Bifurcation Analysis of a Rigid Rotor on Electromagnetic Bearings

The work resulted in a paper published in

C. Nataraj and Steven Marx, 2007, ASME IDETC Conferences.

Abstract

This paper considers a one degree of freedom rotor supported on an electromagnetic bearing in a feedback control loop. A nonlinear model of an electromagnetic bearing is developed and a nondimensional model is derived for the system with two distinct parameters corresponding to the controller gain and the static load. Nonlinear analysis is carried out as a function of these two parameters and bifurcation diagrams are derived. The results reveal a very interesting panoply of fixed points with varying stability conditions. Numerical simulations are carried out to confirm the results of nonlinear analysis. Practical implications of the nonlinear analysis results are discussed.