Description of an Electrodynamic Self-Bearing Permanent Magnet Machine

This paper aims to give a description of a passively levitated self-bearing permanent magnet motor principle. The windings of a permanent magnet motor are connected in such a way that they are also coupled to the p ± 1 harmonics due to a rotor off-centering. They allow for eddy currents to flow inside a short-circuit path when the rotor is out-centered, and in consequence to generate radial force according to the principle of radial heteropolar electrodynamic bearings. The general principles are described, and a 2-D-FE time-dependent model illustrates those principles on two application cases. The theoretical feasibility of this passively levitated permanent magnet motor is shown on a slotless application case.