A Novel Nonlinear Eddy Current Damping Design Method for a Triple-magnet Magnetic Suspension Dynamic Vibration Absorber

A novel Nonlinear Eddy Current Damping (NL-ECD) design method for a Triple-magnet Magnetic Suspension Dynamic Vibration Absorber (TMSDVA) is proposed, modelled, and tested. The implementation of the NL-ECD design method is completely passive and does not require an external energy supply. First, the mathematical model of the TMSDVA vibration reduction system is established. Additionally, the NL-ECD calculation model is also derived. The NL-ECD coefficient can be designed and adjusted by changing the dimensional parameters of the damping tube. Then the correctness of the NL-ECD derivation process is verified through simulations and experiments. It is found that the NL-ECD coefficient is strongly related to the position of the moving magnet. And the simulation results show the same trend as the experimental results. Next, the dynamic responses of the TMSDVA with NL-ECD are studied. Using NL-ECD can not only eliminate higher branch responses in the TMSDVA vibration reduction system, but also retain non-linear dynamics response characteristics of the system. As a result, a better vibration reduction effect of the TMSDVA is obtained. Moreover, the NL-ECD design method proposed in this paper can be either applicable to the TMSDVA or applicable to other types of magnetic DVAs using cylindrical magnets or ring magnets.