Thermal runaway of a 1 T cryocooler-cooled oxide superconducting pulsed coil in Ac operation

H. Miyazaki, S. Harada, M. Iwakuma, K. Funaki, H. Hayashi, A. Tomioka

Research output: Contribution to journalArticle

6 Citations (Scopus)

Abstract

We designed and fabricated a l T cryocooler-cooled oxide superconducting pulsed coil with Bi2223 multifilamentary flat wires. Previously we studied temperature dependence of the thermal runaway current of the pulsed coil in dc operation. The thermal runaway current was higher than the critical current that was defined as the current where the electric field 10-4 V/m was generated on average over the whole length of the conductor. In this paper, we studied the coil temperature and the ac loss dependence of the thermal runaway current in ac operation. We operated the coil at 0.5 to 5 Hz with a sinusoidal-waveform transport current. The initial coil temperature was set between 30 and 100 K. The thermal runaway current decreased monotonically with increasing temperature in a similar way to dc operation. However, in a low temperature region, the thermal runaway current was restricted to a lower level than that in dc operation due to the ac loss. We discuss the frequency dependence of thermal runaway current in ac operation.

Original languageEnglish
Pages (from-to)1663-1666
Number of pages4
JournalIEEE Transactions on Applied Superconductivity
Volume15
Issue number2 PART II
DOIs
Publication statusPublished - Jun 1 2005

Fingerprint

Oxides
coils
oxides
Temperature
Critical currents
Hot Temperature
temperature
high current
Electric fields
critical current
Wire
waveforms
conductors
wire
temperature dependence
electric fields

All Science Journal Classification (ASJC) codes

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

Cite this

Thermal runaway of a 1 T cryocooler-cooled oxide superconducting pulsed coil in Ac operation. / Miyazaki, H.; Harada, S.; Iwakuma, M.; Funaki, K.; Hayashi, H.; Tomioka, A.

In: IEEE Transactions on Applied Superconductivity, Vol. 15, No. 2 PART II, 01.06.2005, p. 1663-1666.

Research output: Contribution to journalArticle

Miyazaki, H. ; Harada, S. ; Iwakuma, M. ; Funaki, K. ; Hayashi, H. ; Tomioka, A. / Thermal runaway of a 1 T cryocooler-cooled oxide superconducting pulsed coil in Ac operation. In: IEEE Transactions on Applied Superconductivity. 2005 ; Vol. 15, No. 2 PART II. pp. 1663-1666.
@article{20e31b046f4744f3b0f4147c236a83f8,
title = "Thermal runaway of a 1 T cryocooler-cooled oxide superconducting pulsed coil in Ac operation",
abstract = "We designed and fabricated a l T cryocooler-cooled oxide superconducting pulsed coil with Bi2223 multifilamentary flat wires. Previously we studied temperature dependence of the thermal runaway current of the pulsed coil in dc operation. The thermal runaway current was higher than the critical current that was defined as the current where the electric field 10-4 V/m was generated on average over the whole length of the conductor. In this paper, we studied the coil temperature and the ac loss dependence of the thermal runaway current in ac operation. We operated the coil at 0.5 to 5 Hz with a sinusoidal-waveform transport current. The initial coil temperature was set between 30 and 100 K. The thermal runaway current decreased monotonically with increasing temperature in a similar way to dc operation. However, in a low temperature region, the thermal runaway current was restricted to a lower level than that in dc operation due to the ac loss. We discuss the frequency dependence of thermal runaway current in ac operation.",
author = "H. Miyazaki and S. Harada and M. Iwakuma and K. Funaki and H. Hayashi and A. Tomioka",
year = "2005",
month = "6",
day = "1",
doi = "10.1109/TASC.2005.849226",
language = "English",
volume = "15",
pages = "1663--1666",
journal = "IEEE Transactions on Applied Superconductivity",
issn = "1051-8223",
publisher = "Institute of Electrical and Electronics Engineers Inc.",
number = "2 PART II",

}

TY - JOUR

T1 - Thermal runaway of a 1 T cryocooler-cooled oxide superconducting pulsed coil in Ac operation

AU - Miyazaki, H.

AU - Harada, S.

AU - Iwakuma, M.

AU - Funaki, K.

AU - Hayashi, H.

AU - Tomioka, A.

PY - 2005/6/1

Y1 - 2005/6/1

N2 - We designed and fabricated a l T cryocooler-cooled oxide superconducting pulsed coil with Bi2223 multifilamentary flat wires. Previously we studied temperature dependence of the thermal runaway current of the pulsed coil in dc operation. The thermal runaway current was higher than the critical current that was defined as the current where the electric field 10-4 V/m was generated on average over the whole length of the conductor. In this paper, we studied the coil temperature and the ac loss dependence of the thermal runaway current in ac operation. We operated the coil at 0.5 to 5 Hz with a sinusoidal-waveform transport current. The initial coil temperature was set between 30 and 100 K. The thermal runaway current decreased monotonically with increasing temperature in a similar way to dc operation. However, in a low temperature region, the thermal runaway current was restricted to a lower level than that in dc operation due to the ac loss. We discuss the frequency dependence of thermal runaway current in ac operation.

AB - We designed and fabricated a l T cryocooler-cooled oxide superconducting pulsed coil with Bi2223 multifilamentary flat wires. Previously we studied temperature dependence of the thermal runaway current of the pulsed coil in dc operation. The thermal runaway current was higher than the critical current that was defined as the current where the electric field 10-4 V/m was generated on average over the whole length of the conductor. In this paper, we studied the coil temperature and the ac loss dependence of the thermal runaway current in ac operation. We operated the coil at 0.5 to 5 Hz with a sinusoidal-waveform transport current. The initial coil temperature was set between 30 and 100 K. The thermal runaway current decreased monotonically with increasing temperature in a similar way to dc operation. However, in a low temperature region, the thermal runaway current was restricted to a lower level than that in dc operation due to the ac loss. We discuss the frequency dependence of thermal runaway current in ac operation.

UR - http://www.scopus.com/inward/record.url?scp=22044450071&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=22044450071&partnerID=8YFLogxK

U2 - 10.1109/TASC.2005.849226

DO - 10.1109/TASC.2005.849226

M3 - Article

AN - SCOPUS:22044450071

VL - 15

SP - 1663

EP - 1666

JO - IEEE Transactions on Applied Superconductivity

JF - IEEE Transactions on Applied Superconductivity

SN - 1051-8223

IS - 2 PART II

ER -