Dynamic Magnetic Resistance Characteristics of High- T C Superconducting Maglev Prototype Vehicle under Fluctuating External Magnetic Field

Previous work has studied the magnetic resistance ( F mr ) of high-temperature superconducting (HTS) maglev vehicles operating at a speed lower than 40 km/h, but the characteristics of F mr at higher operation speeds are still unclear. Based on the high-speed rotating simulation platform, this paper studies the dynamic magnetic resistance of maglev vehicle at a speed up to 250 km/h. By stacking silicon steel sheets on a circular permanent magnet guideway (PMG) to form a periodically fluctuating external magnetic field, the characteristics of the influence of strong magnetic field fluctuations on the magnetic resistance of the maglev vehicle under high-speed movement are obtained. The transient magnetic resistance of the HTS maglev system oscillates with time. The oscillation amplitude increases approximately linearly with the operating speed and is closely related to the initial magnetization state of the HTS superconductor. Due to the asymmetry of the oscillation, there is a net average magnetic resistance, whose value increases linearly with the speed, and the rate of change is dominated by the initial magnetization state of the superconductor. The oscillating characteristics of transient magnetic resistance make the net average magnetic resistance much smaller than the magnetic levitation force. The frequency spectrum of magnetic resistance oscillation shows two characteristic frequencies of 5.3 Hz and 53 Hz, and they are independent of the driving frequency.