We studied the levitation of a $YB{a}_{2}C{u}_3{O}_7$ (YBCO) melt-textured superconducting specimen above a closed path of permanent magnets. The superconductor was magnetized with an auxiliary permanent magnet before brought to the path of magnets. This way, the superconducting levitation in the mixed state was achieved. The vertical and horizontal forces acting on the superconductor were calculated by means of two models. One model considers that the superconductor is in the Meissner state and assumes that it is possible to take into account the demagnetizing field by using a single average parameter. The second model considers that the superconductor with trapped field behaves as a permanent magnet with a uniform magnetization. The total force on the superconductor in the mixed state is result of the superposition of these two contributions. In order to validate the model, the height of levitation and the frequency of horizontal oscillations were measured. Both variables were then calculated with the model fed with experimental information. The calculated values were in agreement with the measured ones.

我们研究了 $ÿ乙{\mathrm{一种}}_{\mathrm{2个}}C{ü}_3{Ø}_7$（YBCO）处于永久磁铁闭合路径上方的熔融织构超导样品。在将超导体带到磁体路径之前，先用辅助永磁体对其进行了磁化。这样，实现了混合状态下的超导悬浮。通过两个模型计算作用在超导体上的垂直和水平力。一种模型认为超导体处于迈斯纳状态，并假设可以通过使用单个平均参数来考虑退磁场。第二种模型认为，具有被困场的超导体表现为具有均匀磁化强度的永磁体。处于混合状态的超导体上的总力是这两个贡献叠加的结果。为了验证模型，测量了悬浮的高度和水平振荡的频率。然后，使用提供实验信息的模型来计算这两个变量。计算值与实测值一致。