Model of Eddy Current Damping Mechanism for the Suppression of Beam Vibrations

The movement of a conductor through a stationary magnetic field or a time varying magnetic field through a stationary conductor generates electromagnetic forces that can be used to suppress the vibrations of a flexible structure. In the present study, a new electromagnetic damping mechanism is introduced. This mechanism differs from previously developed electromagnetic braking systems and eddy current dampers because the system investigated in the following manuscript uses the radial magnetic flux of a permanent magnet to generate the electromagnetic damping force rather than the flux perpendicular to the magnet’s face as done in other studies. One important advantage of the proposed mechanism is that it is simple and easy to be applied. Additionally, a single magnet can be used to damp the transverse vibrations that are present in many structures. Furthermore, it doesn’t require any electronic devices or external power supplies, therefore functioning as a non-contacting passive damper. A theoretical model of the system is derived using electromagnetic theory, enabling us to estimate the electromagnetic damping force induced on the structure. The proposed eddy current damper was constructed and experiments were performed to verify the precision of the theoretical model. It is found that the proposed eddy current damping mechanism increases the damping ratio by up to 150 times and provides sufficient damping force to quickly suppress the beam’s vibration.