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Title: Low ac loss geometries in YBCO coated conductors and impact on conductor stability

Abstract

Reduction of ac losses in applied ac fields can be accomplished through either the creation of filaments and bridging in YBCO coated conductors or an assembly of narrow width YBCO tapes. The ac losses for each of these geometries were measured at 77 K in perpendicular ac fields up to 100 mT. While ac loss reduction was achieved with YBCO filaments created through laser scribing and inkjet deposition, the assembly of stacked YBCO conductor provides an alternative method of ac loss reduction. When compared to a 4-mm wide YBCO coated conductor with a critical current of 60 A, the ac loss in a stack of 2-mm wide YBCO coated conductors with a similar total critical current was reduced. While the reduction in ac loss in a 2-mm wide stack coincided with the reduction in the engineering current density of the conductor, further reduction of ac loss was obtained through the splicing of the 2-mm wide tapes with low resistance solders. To better determine the practicality of these methods from a stability point of view, a numerical analysis was carried out to determine the influence of bridging and splicing on stability of a YBCO coated conductor for both liquid nitrogen-cooled andmore » conduction cooled geometries.« less

Authors:
 [1];  [1];  [1];  [2];  [2];  [3];  [3]
  1. ORNL
  2. American Superconductor Corporation, Westborough, MA
  3. SuperPower Incorporated, Schenectady, New York
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
OE USDOE - Office of Electric Transmission and Distribution
OSTI Identifier:
931705
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physica C; Journal Volume: 463-465
Country of Publication:
United States
Language:
English
Subject:
24 POWER TRANSMISSION AND DISTRIBUTION; AC LOSSES; CRITICAL CURRENT; CURRENT DENSITY; DEPOSITION; LASERS; NUMERICAL ANALYSIS; SPLICING; STABILITY; ac loss; YBCO tapes; filamentization; conductor stability

Citation Formats

Duckworth, Robert C, List III, Frederick Alyious, Paranthaman, Mariappan Parans, Rupich, M. W., Zhang, W., Xie, Y. Y., and Selvamanickam, V. Low ac loss geometries in YBCO coated conductors and impact on conductor stability. United States: N. p., 2007. Web. doi:10.1016/j.physc.2007.03.499.
Duckworth, Robert C, List III, Frederick Alyious, Paranthaman, Mariappan Parans, Rupich, M. W., Zhang, W., Xie, Y. Y., & Selvamanickam, V. Low ac loss geometries in YBCO coated conductors and impact on conductor stability. United States. doi:10.1016/j.physc.2007.03.499.
Duckworth, Robert C, List III, Frederick Alyious, Paranthaman, Mariappan Parans, Rupich, M. W., Zhang, W., Xie, Y. Y., and Selvamanickam, V. Mon . "Low ac loss geometries in YBCO coated conductors and impact on conductor stability". United States. doi:10.1016/j.physc.2007.03.499.
@article{osti_931705,
title = {Low ac loss geometries in YBCO coated conductors and impact on conductor stability},
author = {Duckworth, Robert C and List III, Frederick Alyious and Paranthaman, Mariappan Parans and Rupich, M. W. and Zhang, W. and Xie, Y. Y. and Selvamanickam, V.},
abstractNote = {Reduction of ac losses in applied ac fields can be accomplished through either the creation of filaments and bridging in YBCO coated conductors or an assembly of narrow width YBCO tapes. The ac losses for each of these geometries were measured at 77 K in perpendicular ac fields up to 100 mT. While ac loss reduction was achieved with YBCO filaments created through laser scribing and inkjet deposition, the assembly of stacked YBCO conductor provides an alternative method of ac loss reduction. When compared to a 4-mm wide YBCO coated conductor with a critical current of 60 A, the ac loss in a stack of 2-mm wide YBCO coated conductors with a similar total critical current was reduced. While the reduction in ac loss in a 2-mm wide stack coincided with the reduction in the engineering current density of the conductor, further reduction of ac loss was obtained through the splicing of the 2-mm wide tapes with low resistance solders. To better determine the practicality of these methods from a stability point of view, a numerical analysis was carried out to determine the influence of bridging and splicing on stability of a YBCO coated conductor for both liquid nitrogen-cooled and conduction cooled geometries.},
doi = {10.1016/j.physc.2007.03.499},
journal = {Physica C},
number = ,
volume = 463-465,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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