Vibration control of a flexible rotor with oil-film bearings by means of active magnetic bearings

In the past, most active vibration control concepts were addressing non-rotating parts. However, many known problems in the field of noise and vibration occur in rotatory systems. Problems of using active control measures for rotating machinery are the energy transfer into a rotating systems as well as finding suited actuator concepts to control lateral vibrations. One of the most utilized passive supports for rotating machinery are Oil-film Bearings. They are widely used in Turbomachinery allowing high loads at high speeds. The availability and the reliability of this type of bearing are very high, since there is only fluid contact between parts with relative motion, ensuring long operational lifetime. On the other hand Active Magnetic Bearings generate forces through magnetic fields, there is no contact between bearing and rotor, and this allows operation with no lubrication and no mechanical wear. In our special application we use only one additional AMB besides the existing oil film bearings for the purpose of active vibration control.