Magnetic Resistance of HTS Maglev Moving Above a Permanent Magnet Guideway with Large Magnetic Field Fluctuations

Unlike the magnetic levitation characteristics that most research focuses on, this article focuses on the magnetic resistance of high-temperature superconductor (HTS) maglev system. By superimposing iron sheets on the permanent magnet (PM) track to create significant magnetic field fluctuations, we studied the magnetic resistance of HTS-PM maglev caused by the fluctuating magnetic field, and used the rotating orbit platform to study the influence of the running speed and the field cooling height (FCH) on the magnetic resistance. The magnetic resistance is found mainly originating from the self-stabilizing characteristic of type II superconductor in an uneven external magnetic field, showing oscillation characteristics near a certain equilibrium value, with nearly constant amplitude at a given FCH and running speed. Spectrum analysis shows that the main frequency of the oscillation is the same as the frequency of the alternating magnetic field received by the maglev vehicle during running above the fluctuating magnetic field, revealing that this is a forced vibration driven by a fluctuating magnetic field. The oscillation amplitude and power density increase steadily with the increase of FCH, and show the characteristics of first increasing and then reaching saturation with the increase of running speed. The research results reveal that there is an inherent correlation between the oscillation of the magnetic resistance and the stability of the system.