Superconducting magnetic bearing for a flywheel energy storage system using superconducting coils and bulk superconductors

K. Nagashima, H. Seino, Naomichi Sakai, Masato Murakami

Research output: Contribution to journalArticle

22 Citations (Scopus)

Abstract

Stable levitation or suspension of a heavy object in mid-air can be realized using a combination of a permanent magnet and a bulk superconductor with high critical current density, in that the force density has reached 100 kN/m2. The superconducting flywheel system for energy storage is attractive due to a great reduction in the rotational loss of the bearings. So long as a permanent magnet is used as a magnetic source, however, the electromagnetic force (EMF) is essentially limited by its field strength. In order to overcome such a limitation, we employed a superconducting coil/magnet as a magnetic source and studied the EMF characteristics of bulk superconductors in high-magnetic fields. We also measured the EMF between a bulk superconductor and a specially designed superconducting coil having a high field gradient, and confirmed that the EMF reached 9450 N (force density: 2507 kN/m2).

Original languageEnglish
Pages (from-to)1244-1249
Number of pages6
JournalPhysica C: Superconductivity and its Applications
Volume469
Issue number15-20
DOIs
Publication statusPublished - 2009 Oct 15

Fingerprint

flywheels
magnetic bearings
Magnetic bearings
Flywheels
energy storage
Energy storage
Superconducting materials
coils
Permanent magnets
Bearings (structural)
Critical current density (superconductivity)
electromagnetism
permanent magnets
Magnets
Suspensions
magnet coils
Magnetic fields
levitation
Air
Superconducting coils

Keywords

  • Bulk superconductor
  • Energy storage
  • Flywheel
  • Magnetic bearing
  • Superconducting coil

ASJC Scopus subject areas

  • Condensed Matter Physics
  • Electrical and Electronic Engineering
  • Energy Engineering and Power Technology
  • Electronic, Optical and Magnetic Materials

Cite this

@article{a0bab31a45bb49bfb5bd244329ba593a,
title = "Superconducting magnetic bearing for a flywheel energy storage system using superconducting coils and bulk superconductors",
abstract = "Stable levitation or suspension of a heavy object in mid-air can be realized using a combination of a permanent magnet and a bulk superconductor with high critical current density, in that the force density has reached 100 kN/m2. The superconducting flywheel system for energy storage is attractive due to a great reduction in the rotational loss of the bearings. So long as a permanent magnet is used as a magnetic source, however, the electromagnetic force (EMF) is essentially limited by its field strength. In order to overcome such a limitation, we employed a superconducting coil/magnet as a magnetic source and studied the EMF characteristics of bulk superconductors in high-magnetic fields. We also measured the EMF between a bulk superconductor and a specially designed superconducting coil having a high field gradient, and confirmed that the EMF reached 9450 N (force density: 2507 kN/m2).",
keywords = "Bulk superconductor, Energy storage, Flywheel, Magnetic bearing, Superconducting coil",
author = "K. Nagashima and H. Seino and Naomichi Sakai and Masato Murakami",
year = "2009",
month = "10",
day = "15",
doi = "10.1016/j.physc.2009.05.245",
language = "English",
volume = "469",
pages = "1244--1249",
journal = "Physica C: Superconductivity and its Applications",
issn = "0921-4534",
publisher = "Elsevier",
number = "15-20",

}

TY - JOUR

T1 - Superconducting magnetic bearing for a flywheel energy storage system using superconducting coils and bulk superconductors

AU - Nagashima, K.

AU - Seino, H.

AU - Sakai, Naomichi

AU - Murakami, Masato

PY - 2009/10/15

Y1 - 2009/10/15

N2 - Stable levitation or suspension of a heavy object in mid-air can be realized using a combination of a permanent magnet and a bulk superconductor with high critical current density, in that the force density has reached 100 kN/m2. The superconducting flywheel system for energy storage is attractive due to a great reduction in the rotational loss of the bearings. So long as a permanent magnet is used as a magnetic source, however, the electromagnetic force (EMF) is essentially limited by its field strength. In order to overcome such a limitation, we employed a superconducting coil/magnet as a magnetic source and studied the EMF characteristics of bulk superconductors in high-magnetic fields. We also measured the EMF between a bulk superconductor and a specially designed superconducting coil having a high field gradient, and confirmed that the EMF reached 9450 N (force density: 2507 kN/m2).

AB - Stable levitation or suspension of a heavy object in mid-air can be realized using a combination of a permanent magnet and a bulk superconductor with high critical current density, in that the force density has reached 100 kN/m2. The superconducting flywheel system for energy storage is attractive due to a great reduction in the rotational loss of the bearings. So long as a permanent magnet is used as a magnetic source, however, the electromagnetic force (EMF) is essentially limited by its field strength. In order to overcome such a limitation, we employed a superconducting coil/magnet as a magnetic source and studied the EMF characteristics of bulk superconductors in high-magnetic fields. We also measured the EMF between a bulk superconductor and a specially designed superconducting coil having a high field gradient, and confirmed that the EMF reached 9450 N (force density: 2507 kN/m2).

KW - Bulk superconductor

KW - Energy storage

KW - Flywheel

KW - Magnetic bearing

KW - Superconducting coil

UR - http://www.scopus.com/inward/record.url?scp=68149134613&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=68149134613&partnerID=8YFLogxK

U2 - 10.1016/j.physc.2009.05.245

DO - 10.1016/j.physc.2009.05.245

M3 - Article

AN - SCOPUS:68149134613

VL - 469

SP - 1244

EP - 1249

JO - Physica C: Superconductivity and its Applications

JF - Physica C: Superconductivity and its Applications

SN - 0921-4534

IS - 15-20

ER -