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Title: Measurements of AC Losses and Current Distribution in Superconducting Cables

Abstract

This paper presents our new experimental facility and techniques to measure ac loss and current distribution between the layers for High Temperature Superconducting (HTS) cables. The facility is powered with a 45 kVA three-phase power supply which can provide three-phase currents up to 5 kA per phase via high current transformers. The system is suitable for measurements at any frequency between 20 and 500 Hz to better understand the ac loss mechanisms in HTS cables. In this paper, we will report techniques and results for ac loss measurements carried out on several HTS cables with and without an HTS shielding layer. For cables without a shielding layer, care must be taken to control the effect of the magnetic fields from return currents on loss measurements. The waveform of the axial magnetic field was also measured by a small pick-up coil placed inside a two-layer cable. The temporal current distribution between the layers can be calculated from the waveform of the axial field.

Authors:
 [1];  [1];  [2];  [3];  [4]
  1. Los Alamos National Laboratory (LANL)
  2. ORNL
  3. AMSC
  4. AMER Superconductor Corp, Devens, MA 01434
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
Work for Others (WFO)
OSTI Identifier:
1036584
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: IEEE Transactions on Applied Superconductivity; Journal Volume: 21; Journal Issue: 3
Country of Publication:
United States
Language:
English
Subject:
24 POWER TRANSMISSION AND DISTRIBUTION; AC LOSSES; AVAILABILITY; CABLES; DISTRIBUTION; MAGNETIC FIELDS; SHIELDING; SUPERCONDUCTING CABLES; TRANSFORMERS; WAVE FORMS

Citation Formats

Nguyen, Doan A, Ashworth, Stephen P, Duckworth, Robert C, Carter, Bill, and Fleshler, Steven. Measurements of AC Losses and Current Distribution in Superconducting Cables. United States: N. p., 2011. Web. doi:10.1109/TASC.2010.2089415.
Nguyen, Doan A, Ashworth, Stephen P, Duckworth, Robert C, Carter, Bill, & Fleshler, Steven. Measurements of AC Losses and Current Distribution in Superconducting Cables. United States. doi:10.1109/TASC.2010.2089415.
Nguyen, Doan A, Ashworth, Stephen P, Duckworth, Robert C, Carter, Bill, and Fleshler, Steven. 2011. "Measurements of AC Losses and Current Distribution in Superconducting Cables". United States. doi:10.1109/TASC.2010.2089415.
@article{osti_1036584,
title = {Measurements of AC Losses and Current Distribution in Superconducting Cables},
author = {Nguyen, Doan A and Ashworth, Stephen P and Duckworth, Robert C and Carter, Bill and Fleshler, Steven},
abstractNote = {This paper presents our new experimental facility and techniques to measure ac loss and current distribution between the layers for High Temperature Superconducting (HTS) cables. The facility is powered with a 45 kVA three-phase power supply which can provide three-phase currents up to 5 kA per phase via high current transformers. The system is suitable for measurements at any frequency between 20 and 500 Hz to better understand the ac loss mechanisms in HTS cables. In this paper, we will report techniques and results for ac loss measurements carried out on several HTS cables with and without an HTS shielding layer. For cables without a shielding layer, care must be taken to control the effect of the magnetic fields from return currents on loss measurements. The waveform of the axial magnetic field was also measured by a small pick-up coil placed inside a two-layer cable. The temporal current distribution between the layers can be calculated from the waveform of the axial field.},
doi = {10.1109/TASC.2010.2089415},
journal = {IEEE Transactions on Applied Superconductivity},
number = 3,
volume = 21,
place = {United States},
year = 2011,
month = 1
}
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