Title:
SUPERCONDUCTING MAGNET AND NUCLEAR MAGNETIC RESONANCE DEVICE
Document Type and Number:
WIPO Patent Application WO/2012/157745
Kind Code:
A1
Abstract:
Disclosed is a superconducting magnet in which uniformity of the central magnetic field is secured by eliminating magnetisation produced by the shielding current of the superconducting winding and thus making the current that is passed to the superconducting winding uniform. The super conducting magnet is provided with a superconducting winding (2) and an outside AC winding (4) constituted by a superconductor or non-superconductor that is wound coaxially with the superconducting winding (2), outside the layer of superconducting winding (2). Magnetisation is eliminated by applying an AC magnetic field in a direction perpendicular to the direction of magnetisation produced by the shielding current generated in the superconducting winding (2), by passing an AC current to the outside AC winding (4). Also, there is provided an inside AC winding (7) constituted by a superconductor or non-superconductor that is wound coaxially with the superconducting winding (2), inside the layer of superconducting winding (2). The current direction in which current is passed in the outside AC winding (4) and the current direction in which current is passed in the inside AC winding (7) are made to be in mutually opposite directions.
Inventors:
KAJIKAWA KAZUHIRO (JP)
FUNAKI KAZUO (JP)
FUNAKI KAZUO (JP)
Application Number:
PCT/JP2012/062777
Publication Date:
November 22, 2012
Filing Date:
May 18, 2012
Export Citation:
Assignee:
UNIV KYUSHU NAT UNIV CORP (JP)
KAJIKAWA KAZUHIRO (JP)
FUNAKI KAZUO (JP)
KAJIKAWA KAZUHIRO (JP)
FUNAKI KAZUO (JP)
International Classes:
H01F6/00; G01R33/3815; G01R33/3875; H01F5/00
Foreign References:
| JPS574541A | 1982-01-11 | |||
| JPH08279411A | 1996-10-22 | |||
| JP2007335616A | 2007-12-27 |
Other References:
GRIGORII P ET AL.: "Theory of the longitudinal vortex-shaking effect in superconducting strips", JOURNALS OF THE AMERICAN PHYSICAL SOCIETY, vol. 67, no. 10, 24 March 2003 (2003-03-24), pages 104511-1 - - 104511-8, XP055137463
M.A.R.LEBLANC ET AL.: "Generation of quasi-reversibility in a commercial Bi:2223/Ag type by vortex shaking with varying orthogonal magnetic fields", ELSEVIER, PHYSICA C, vol. 361, no. ISS. 4, 2001, pages 251 - 259, XP004308651
KAZUHIRO KAJIKAWA ET AL.: "Reduction of Magnetization in Windings Composed of HTS Tapes", RESEARCH INSTITUTE OF SUPERCONDUCTOR SCIENCE AND SYSTEMS HOKOKU, vol. 22, no. 3, March 2012 (2012-03-01), pages 13 - 21, XP011446795
See also references of EP 2711940A4
KAZUO FUNAKI; KAORU YAMAFUJI: "Abnormal Transverse-Field Effects in Nonideal Type II Superconductors I. A Linear Array of Monofilamentary Wires", JAPANESE JOURNAL OF APPLIED PHYSICS, vol. 21, no. 2, February 1982 (1982-02-01), pages 299 - 304
KAZUO FUNAKI; TERUHIDE NIIDOME; KAORU YAMAFUJI: "Abnormal Transverse-Field Effects in Nonideal Type 2 Superconductors. II. Influence of Dimention Ratios in a Superconducting Ribbon", JAPANESE JOURNAL OF APPLIED PHYSICS, vol. 21, no. 8, August 1982 (1982-08-01), pages 1121 - 1126
KAZUO FUNAKI; MINORU NODA; KAORU YAMAFUJI: "Abnormal Transverse-Field Effects in Nonideal Type 2 Superconductors. III. A Theory for an AC-Induced Decrease in the Semi-Quasistatic Magnetization Parallel to a DC Bias Field", JAPANESE JOURNAL OF APPLIED PHYSICS, vol. 21, no. 11, November 1982 (1982-11-01), pages 1580 - 1587
KAZUO FUNAKI; TERUHIDE NIIDOME; KAORU YAMAFUJI: "Abnormal Transverse-Field Effects in Current Carrying Superconducting Wires", TECHNOLOGY REPORTS OF KYUSHU UNIVERSITY, vol. 56, no. 1, January 1983 (1983-01-01), pages 45 - 51
ERNST HELMUT BRANDT; GRIGORII P.MIKITIK: "Why an ac Magnetic Field Shifts the Irreversibility Line in Type-II Superconductors", PHYSICAL REVIEW LETTERS, vol. 89, no. 2, July 2002 (2002-07-01), pages 027002
ERNST HELMUT BRANDT; GRIGORII P.MIKITIK: "Shaking of the critical state by a small transverse ac field can cause rapid relaxation in superconductors", SUPERCONDUCTOR SCIENCE AND TECHNOLOGY, vol. 17, no. 2, February 2004 (2004-02-01), pages S1 - S5
M.A.R.LEBLANC ET AL.: "Generation of quasi-reversibility in a commercial Bi:2223/Ag type by vortex shaking with varying orthogonal magnetic fields", ELSEVIER, PHYSICA C, vol. 361, no. ISS. 4, 2001, pages 251 - 259, XP004308651
KAZUHIRO KAJIKAWA ET AL.: "Reduction of Magnetization in Windings Composed of HTS Tapes", RESEARCH INSTITUTE OF SUPERCONDUCTOR SCIENCE AND SYSTEMS HOKOKU, vol. 22, no. 3, March 2012 (2012-03-01), pages 13 - 21, XP011446795
See also references of EP 2711940A4
KAZUO FUNAKI; KAORU YAMAFUJI: "Abnormal Transverse-Field Effects in Nonideal Type II Superconductors I. A Linear Array of Monofilamentary Wires", JAPANESE JOURNAL OF APPLIED PHYSICS, vol. 21, no. 2, February 1982 (1982-02-01), pages 299 - 304
KAZUO FUNAKI; TERUHIDE NIIDOME; KAORU YAMAFUJI: "Abnormal Transverse-Field Effects in Nonideal Type 2 Superconductors. II. Influence of Dimention Ratios in a Superconducting Ribbon", JAPANESE JOURNAL OF APPLIED PHYSICS, vol. 21, no. 8, August 1982 (1982-08-01), pages 1121 - 1126
KAZUO FUNAKI; MINORU NODA; KAORU YAMAFUJI: "Abnormal Transverse-Field Effects in Nonideal Type 2 Superconductors. III. A Theory for an AC-Induced Decrease in the Semi-Quasistatic Magnetization Parallel to a DC Bias Field", JAPANESE JOURNAL OF APPLIED PHYSICS, vol. 21, no. 11, November 1982 (1982-11-01), pages 1580 - 1587
KAZUO FUNAKI; TERUHIDE NIIDOME; KAORU YAMAFUJI: "Abnormal Transverse-Field Effects in Current Carrying Superconducting Wires", TECHNOLOGY REPORTS OF KYUSHU UNIVERSITY, vol. 56, no. 1, January 1983 (1983-01-01), pages 45 - 51
ERNST HELMUT BRANDT; GRIGORII P.MIKITIK: "Why an ac Magnetic Field Shifts the Irreversibility Line in Type-II Superconductors", PHYSICAL REVIEW LETTERS, vol. 89, no. 2, July 2002 (2002-07-01), pages 027002
ERNST HELMUT BRANDT; GRIGORII P.MIKITIK: "Shaking of the critical state by a small transverse ac field can cause rapid relaxation in superconductors", SUPERCONDUCTOR SCIENCE AND TECHNOLOGY, vol. 17, no. 2, February 2004 (2004-02-01), pages S1 - S5
Attorney, Agent or Firm:
HIRAI YASUO (JP)
Yasuo Hirai (JP)
Yasuo Hirai (JP)
Download PDF:
Claims: