Influence of AC External Magnetic Field on the Levitation Force Relaxation of HTS Bulk Above NdFeB Guideway

• Published in: Journal of superconductivity and novel magnetism Vol. 24; no. 5; pp. 1809 - 1813
• Main Authors: Liu, Minxian, Lu, Yiyun, Wang, Suyu, Ma, Guangtong
• Format: Journal Article
• Language: English
• Published: Boston Springer US 01-07-2011; Springer
• Subjects: Air conditioning; Applied sciences; Attenuation; Characterization and Evaluation of Materials; Condensed Matter Physics; Decay; Electromagnets; Electronics; Exact sciences and technology; Levitation; Magnetic fields; Magnetic Materials; Magnetism; Original Paper; Permanent magnets; Physics; Physics and Astronomy; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Strongly Correlated Systems; Superconducting devices; Superconductivity; HTS bulk; NdFeB guideway; Levitation force relaxation; AC magnetic field; External field; Force measurement; Rail vehicle; Experimental device; Iron alloy; Rare earth metal alloy; Magnetic field effect; Time dependence; Transition metal alloy; Non uniform field; Guideway; Permanent magnet; Barium Copper Yttrium Oxides Mixed; High temperature superconductor; Magnetic levitation; Neodymium alloy
• ISSN: 1557-1939; 1557-1947
• DOI: 10.1007/s10948-011-1128-2

In the present High-Temperature Superconducting (HTS) maglev vehicle system, the air gaps between the adjacent permanent magnets make the magnetic fields above the NdFeB guideway non-uniform. So one is required to study the characteristics of levitation force of the HTS bulk influenced by non-uniform fields. In this paper, we have studied the characteristics of the levitation force relaxation by an experiment in which the AC external magnetic field generated by an electromagnet is used to simulate the time-varying external magnetic field caused by the inhomogeneity of the NdFeB guideway. From the experiment results, it is found that the levitation force is attenuated with the application of the AC external magnetic field, and the decay is increased with the amplitude of the AC magnetic field, but the decay is almost independent of the frequency of the AC magnetic field.