Research On Levitation And Electromagnetic Properties Of Magnetized Bulk High Temperature Superconductor Magnet

The magnetized bulk high-Tc superconductor magnet (MBSCM) can acquire far larger trapped magnetic flux than the normal permanent magnet (PM). Introducing the MBSCM into the translation symmetrical high-Tc superconducting (HTS) maglev system can improve both the efficiency of bulk superconductor and the levitation performance of HTS maglev system. Different from the normal PM, the trapped flux of MBSCM is sustained by the induced supercurrent produced during the magnetization process, which is sensitive to the magnetization history, the applied field experience and the material behavior of superconductor. It is necessary to investigate the magnetization and levitation performance of MBSCM before the usage in engineering.This paper focuses on the levitation performance of MBSCM in the practical application and the influence from relevant parameters. The MBSCM is prepared by field-cooling method (FCM), with a static field magnetizing apparatus. Short introduction into the FCM, the energy dissipation mechanism and HTS maglev system are contained. Influence of magnetization history on the levitation performance of MBSCM is processed with the change of exciting field, including the field strength, the withdraw rate and the order of application. Influence streams from applied field experience, such as force relaxation and lateral displacement, is also investigated under two different magnetization modes of MBSCM. By drilling hole, insetting functional material and polishing thickness, the relationship between levitation performance and geometric features of MBSCM is studied. The influence of applied field configuration and strength on the levitation performance of MBSCM is completed on the base of three typical PMG pieces. The finite element method (FEM) combined with the 2-D numerical mode is built based on the experimental results and has passed the effectiveness examination. With the multi-field coupling function, the FEM is also used to discuss some electromagnetic properties of MBSCM which are hard to deal with experimental study.The test results, theory analyses and analog computation prove the effectiveness of MBSCM to improve the system levitation performance. Influences of the magnetic intensity, the displacement process, the applied field and the thickness on the levitation performance of MBSCM are discussed and then get some superior working mode and optimization method, which can supply useful data and design basis for the MBSCM in engineering application.