Effect of Eddy Current Damper on the Dynamic Vibration Characteristics of High-Temperature Superconducting Maglev System

The high-temperature superconducting (HTS) magnetic levitation (maglev) has demonstrated many advantages such as self-levitation, self-guidance, environment friendliness by using liquid nitrogen, and low noise. But it has a weakness of low damping, which is not beneficial for the systemic stability and security when the maglev vehicle is disturbed by external environment such as crosswind and track irregularity. To enhance the dynamic stability of the HTS maglev system, a simple and effective approach by inserting eddy current damper (ECD) into the bottom of HTS bulks has been considered. In this paper, we investigated the dynamic effect of ECD on the vibration amplitude and frequency of the HTS maglev system by introducing different thicknesses copper damper underneath the HTS bulks with different velocities by measuring the displacement and acceleration signals of an HTS levitator. In theory, we analyzed the effect of ECD on the dynamic stiffness. Experimental results manifest that the additional copper damper can effectively reduce the vibration amplitude of the HTS levitator, meanwhile it has little influence on the vibration frequency. The ECD has little effect on dynamic stiffness by theoretical analysis. An optimum thickness of copper damper to reduce the dynamic vibration is proposed for the HTS maglev system.