Vibration Analysis of EDS Train Propulsion Systems: A Comparison Between Double-Layer and Single-Layer Coil Configurations

The superconducting electrodynamic suspension (EDS) train utilizes superconducting coils (SCs), levitation and guidance coils (LGCs), propulsion coils (PCs), and damping coils (DCs) for operation, which has the potential for high-speed train. The impact of propulsion systems on vehicle dynamics is extremely important and little studied. Therefore, it is crucial to conduct a comparative study of the dynamic characteristics with different propulsion configurations. This article establishes an equivalent circuit model considering the four electromagnetic systems, including PC, LGC, DC, and SC interactions. This model also incorporates air resistance and vehicle dynamics to capture the electromagnetic-dynamics coupling effects. Secondly, based on the numerical model, the static thrust fluctuation characteristics of both double-layer and single-layer propulsion systems and the vehicle's vibration behavior are investigated. Finally, the damping effects of the DCs on vibration suppression in the propulsion system are discussed. The results show that, after incorporating the PCs into the numerical model, the guidance stiffness of the suspension bogie decreased and levitation stiffness increased. The comparison reveals that the propulsion system has a large impact on the electromagnetic force fluctuation of the system, but a little effect of the dynamics. From the perspective of engineering manufacturing and long-term operational economy, it is therefore suggested that high-speed EDS trains may opt for a single-layer propulsion system.