Levitation properties of maglev systems using soft ferromagnets
Authors:
- 28 January 2015
- journal article
- Published by IOP Publishing in Superconductor Science and Technology
- Vol. 28 (3)
Abstract
Soft ferromagnets are widely used as flux-concentration materials in the design of guideways for superconducting magnetic levitation transport systems. In order to fully understand the influence of soft ferromagnets on the levitation performance, in this work we apply a numerical model based on the functional minimization method and the Bean’s critical state model to study the levitation properties of an infinitely long superconductor immersed in the magnetic field created by a guideway of different sets of infinitely long parallel permanent magnets with soft ferromagnets between them. The levitation force, guidance force, magnetic stiffness and magnetic pole density are calculated considering the coupling between the superconductor and soft ferromagnets. The results show that the levitation performance is closely associated with the permanent magnet configuration and with the location and dimension of the soft ferromagnets. Introducing the soft ferromagnet with a certain width in a few configurations always decreases the levitation force. However, for most configurations, the soft ferromagnets contribute to improve the levitation performance only when they have particular locations and dimensions in which the optimized location and thickness exist to increase the levitation force the most. Moreover, if the superconductor is laterally disturbed, the presence of soft ferromagnets can effectively improve the lateral stability for small lateral displacement and reduce the degradation of levitation force.Keywords
Funding Information
- Fundamental Research Funds for the Central Universities (lzujbky-2014-226, Izujbky-2014-k10)
- National Key Project of Magneto-Restriction Fusion Energy Development Program (2013GB110002)
- Fund of Natural Science Foundation of China (11032006, 11121202, 11472120)
This publication has 47 references indexed in Scilit:
- Magnetic properties of finite superconducting cylinders. II. Nonuniform applied field and levitation forcePhysical Review B, 2001
- Superconducting bearingsSuperconductor Science and Technology, 2000
- Levitation force from high-superconducting thin-film disksPhysical Review B, 1999
- Superconducting magnetic bearings for energy storage flywheelsIEEE Transactions on Applied Superconductivity, 1999
- Calculation of levitation forces in permanent magnet-superconductor systems using finite element analysisJournal of Applied Physics, 1997
- Magnetic levitation of thin superconducting disksPhysica C: Superconductivity and its Applications, 1997
- Levitation force and magnetic stiffness in bulk high-temperature superconductorsJournal of Applied Physics, 1990
- Levitation in PhysicsScience, 1989
- Friction in levitated superconductorsApplied Physics Letters, 1988
- Levitation of a magnet over a flat type II superconductorJournal of Applied Physics, 1988