Improvement of magnetic circuit in levitation system using HTS and soft magnetic material

Mojtaba Ghodsi, Toshiyuki Ueno, Toshiro Higuchi

Research output: Contribution to journalArticle

12 Citations (Scopus)

Abstract

This paper presents improvement of a novel levitation system in which soft magnetic material can be levitated by high-temperature superconductor (HTS). The levitation system consists of two permanent magnets, HTS samples of Dy 1Ba2Cu3Oy (DBCO), and movable yoke with cylindrical parts to which trapped flux in the HTS is gathered and produces an attractive force. The attractive force generally increases with decreasing air gap, but it decreases in a certain air gap called "positive stiffness air gap," which causes positive stiffness to achieve stable levitation of the movable yoke. In this work, we propose closed magnetic circuit using ferromagnetic yoke to enhance the magnetic force and investigate the relationship between attractive force and air gap with different thicknesses of the HTS and different diameters of cylindrical parts. By our proposing closed magnetic circuit, we obtain maximum levitation force of 85 N and stiffness of 4.5 N/mm. The tradeoff between the levitation force and positive stiffness air gap with the thickness of the HTS indicates that there is optimal thickness of HTS for the practical levitation system.

Original languageEnglish
Pages (from-to)4003-4005
Number of pages3
JournalIEEE Transactions on Magnetics
Volume41
Issue number10
DOIs
Publication statusPublished - Oct 2005

Fingerprint

Soft magnetic materials
magnetic circuits
Magnetic circuits
High temperature superconductors
levitation
magnetic materials
high temperature superconductors
stiffness
Stiffness
air
Air
tradeoffs
permanent magnets
Permanent magnets
Fluxes
causes

Keywords

  • High-temperature superconductor
  • Passive levitation
  • Permanent magnet
  • Soft magnetic material

ASJC Scopus subject areas

  • Electrical and Electronic Engineering
  • Physics and Astronomy (miscellaneous)

Cite this

Improvement of magnetic circuit in levitation system using HTS and soft magnetic material. / Ghodsi, Mojtaba; Ueno, Toshiyuki; Higuchi, Toshiro.

In: IEEE Transactions on Magnetics, Vol. 41, No. 10, 10.2005, p. 4003-4005.

Research output: Contribution to journalArticle

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