Magnetic bearings represent a new bearing technology, which has some advantages over conventional fluid film and wiling element bearings for some applications. The paper describes the basic concepts of magnetic thrust bearing operation involving the magnetic actuator, electronic controls, power amplifier, and sensor. The magnetic actuator is a magnetic circuit, which generates attractive forces. These support the rotating shaft. While it is often thought that magnetic bearings are highly nonlinear devices, this paper demonstrates that they are linear in both the perturbation flux and current when used in a double acting configuration. Electronic feedback controls are used to stabilize the bearing. Example design parameters are presented for an application to an industrial canned motor pump.

Issue Section:
Gas Turbines: Structures and Dynamics
Topics:
Pumps, Thrust bearings, Bearings, Actuators, Magnetic bearings, Circuits, Design, Engines, Feedback, Fluid films, Motors, Sensors
1.
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2.
Allaire, P., Imlach, J., McDonald, J., Humphris, R., Lewis, D., Banerjee, B., Blair, B., Claydon, J., and Flack, R., “Design, Construction and Test of a Magnetic Bearing in an Industrial Canned Motor Pump,” Proc. Texas A&M Pump Symposium, Houston, TX, May 1989.
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4.
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,
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Measured and Predicted Force and Stiffness Characteristics of Industrial Magnetic Bearings
,”
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5.
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6.
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7.
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8.
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,
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,
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9.
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10.
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