Analytic Models for Nonlaminated Active Magnetic Thrust Bearings

Analytic models for solid cylindrical electromagnetic actuators are extended to include geometries with a center hole, the configuration typical of thrust-type active magnetic bearings. These models describe the relationship between perturbation to coil current and the variations in mechanical force that result. The models are explicitly dependent on geometric and material properties of the actuator and include the effects of eddy currents, which determine the actuator bandwidth. These models are verified by comparison to high-fidelity finite element results.