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The Relationship between Temperature and Levitation Stiffness of YBCO Bulk for Maglev Vehicle

In order to make the levitation performance of the high temperature superconducting (HTS) magnetic levitation (Maglev) vehicle more stable and safer, in this paper, using a cryogenic measurement system, we measured the levitation forces of YBCO bulk above halbach-type permanent magnet guideway (Halbach PMG) in the temperature range from 77 K to 60 K, then in the condition of deep cryogenic, the levitation forces of YBCO bulk at different field cooling heights (FCHs) were also measured, according to which the levitation stiffness were calculated. The results show that the levitation stiffness of HTS/PMG Maglev system is better at lower temperature. Moreover, when the temperature of YBCO bulk decreases from 77 K to 73 K, the levitation stiffness largely increases in any FCHs. However, after the temperature of the bulk decreases to 73 K, the rate of the levitation stiffness increased gradually reduces. The results are helpful to HTS Maglev vehicle application.