Study of active magnetic bearings (AMB) on non–synchronous rotors

Active Magnetic Bearings (amb)

A magnetic bearing is a bearing which supports a load using magnetic levitation. Magnetic bearings support moving machinery without physical contact, for example, they can levitate a rotating shaft and permit relative motion without friction or wear. In active magnetic bearings (AMB) a stable equilibrium is achieved by means of one or more control loops. The use of control loop for maintaining ...

Rotordynamic Stabilization of Rotors on Electrodynamic Bearings

Actuators for Active Magnetic Bearings

The literature of active magnetic bearing (AMB) technology dates back to at least 1937 when the earliest work that clearly describes an active magnetic bearing system was published by Jesse Beams [1]. Progress on the technology was modest until the late 1970s, when commercial development began to emerge as, for instance, described by Haberman and Liard in 1977 [2]. The state of the art in 1988 ...

Active magnetic bearings - chances and limitations

Magnetic bearings are increasingly being used for a large variety of applications. Their unique features make them attractive for solving classical rotor-bearing problems in a new way and allow novel design approaches for rotating machinery. Classical limitations can be overcome and feature ranges can be extended. Of course, limitations still hold, imposed by principally valid physical constrai...

Control of Active Magnetic Bearings in Turbomolecular Pumps for Rotors with Low Resonance Frequencies of the Blade Wheel

Rotors with high gyroscopic effects and low resonance frequencies caused by the blade wheel (blade frequencies) can lead to stabilization problems in the application field of turbomolecular pumps. If such a rotor is stabilized by active magnetic bearings, the control structure could be destabilized by the splitting up of the rigid body eigen-frequencies caused by the gyroscopic effect. The cont...