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Title: Performance of pancake coils of parallel co-wound Ag/BSCCO tape conductors in static and ramped magnetic fields

Abstract

Critical Currents are reported for several Ag/BSCCO single-pancake coils in static magnetic fields ranging from 0 to 5 T and temperatures from 4.2 K to 105 K. The sample coils were co-wound of one to six tape conductors in parallel. Since the closed loops formed in such an arrangement could lead to eddy current heating or instability in changing fields, one of the coils was also tested in helium gas, in fields ramped at rates of up to 1.5 T/s. For these quasi-adiabatic tests, at each temperature the transport current was set just below the critical value for a preset static field of 3.3 or 4.9 T. The field was then rapidly ramped down to zero, held for 20 sec, and then ramped back up to the original value. The maximum observed temperature transient of about 1.7 K occurred at 9 K, for a field change of 4.75 T. The temperature transients became negligible when the sample was immersed in liquid helium. Above 30 K, the transients were below 1 K. These results give confidence that parallel co-wound HTSC coils are stable in a rapidly-ramped magnetic field, without undue eddy current heating.

Authors:
; ;  [1]; ; ; ; ; ;  [2]
  1. Oak Ridge National Lab., TN (United States)
  2. Intermagnetics General Corp., Latham, NY (United States)
Publication Date:
Research Org.:
Oak Ridge National Lab., TN (United States)
Sponsoring Org.:
USDOE, Washington, DC (United States)
OSTI Identifier:
81047
Report Number(s):
CONF-941013-49
ON: DE95013045; TRN: 95:016369
DOE Contract Number:
AC05-84OR21400
Resource Type:
Technical Report
Resource Relation:
Conference: Applied superconductivity conference, Boston, MA (United States), 16-21 Oct 1994; Other Information: PBD: [1994]
Country of Publication:
United States
Language:
English
Subject:
66 PHYSICS; SUPERCONDUCTING COILS; PERFORMANCE; SUPERCONDUCTING COMPOSITES; SILVER; BARIUM OXIDES; STRONTIUM OXIDES; CALCIUM OXIDES; COPPER OXIDES; PERFORMANCE TESTING; EXPERIMENTAL DATA; TEMPERATURE DEPENDENCE; MAGNETORESISTANCE

Citation Formats

Schwenterly, S.W., Lue, J.W., Lubell, M.S., Walker, M.S., Hazelton, D.W., Haldar, P., Rice, J.A., Hoehn, J.G. Jr., and Motowidlo, L.R. Performance of pancake coils of parallel co-wound Ag/BSCCO tape conductors in static and ramped magnetic fields. United States: N. p., 1994. Web. doi:10.2172/81047.
Schwenterly, S.W., Lue, J.W., Lubell, M.S., Walker, M.S., Hazelton, D.W., Haldar, P., Rice, J.A., Hoehn, J.G. Jr., & Motowidlo, L.R. Performance of pancake coils of parallel co-wound Ag/BSCCO tape conductors in static and ramped magnetic fields. United States. doi:10.2172/81047.
Schwenterly, S.W., Lue, J.W., Lubell, M.S., Walker, M.S., Hazelton, D.W., Haldar, P., Rice, J.A., Hoehn, J.G. Jr., and Motowidlo, L.R. Sat . "Performance of pancake coils of parallel co-wound Ag/BSCCO tape conductors in static and ramped magnetic fields". United States. doi:10.2172/81047. https://www.osti.gov/servlets/purl/81047.
@article{osti_81047,
title = {Performance of pancake coils of parallel co-wound Ag/BSCCO tape conductors in static and ramped magnetic fields},
author = {Schwenterly, S.W. and Lue, J.W. and Lubell, M.S. and Walker, M.S. and Hazelton, D.W. and Haldar, P. and Rice, J.A. and Hoehn, J.G. Jr. and Motowidlo, L.R.},
abstractNote = {Critical Currents are reported for several Ag/BSCCO single-pancake coils in static magnetic fields ranging from 0 to 5 T and temperatures from 4.2 K to 105 K. The sample coils were co-wound of one to six tape conductors in parallel. Since the closed loops formed in such an arrangement could lead to eddy current heating or instability in changing fields, one of the coils was also tested in helium gas, in fields ramped at rates of up to 1.5 T/s. For these quasi-adiabatic tests, at each temperature the transport current was set just below the critical value for a preset static field of 3.3 or 4.9 T. The field was then rapidly ramped down to zero, held for 20 sec, and then ramped back up to the original value. The maximum observed temperature transient of about 1.7 K occurred at 9 K, for a field change of 4.75 T. The temperature transients became negligible when the sample was immersed in liquid helium. Above 30 K, the transients were below 1 K. These results give confidence that parallel co-wound HTSC coils are stable in a rapidly-ramped magnetic field, without undue eddy current heating.},
doi = {10.2172/81047},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Sat Dec 31 00:00:00 EST 1994},
month = {Sat Dec 31 00:00:00 EST 1994}
}

Technical Report:

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