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Title: Calculation of motion induced eddy current forces in null flux coils

Abstract

Time dependent motion induced eddy current forces can be quite difficult to compute. The movement of null flux coils between magnets is approached using a coupled boundary element-circuit approach to compute the forces on the structure. The technique involves treating the magnets as a separate circuit whose current is dictated by the product of the magnet thickness and the working coercivity. The mutual inductance between the windows of the moving null flux coil and the stationary equivalent magnet coil hold the key for predicting lift, guidance, and drag forces on the coil. The rate of change of these inductances with respect to position determines the forces and currents. A steady state approximation to these forces is derived in addition to a numerical simulation when the steady state assumption is invalid. The results compare favorably to laboratory results from a 4 ft. diameter experimental test wheel.

Authors:
;  [1];  [2];  [3]
  1. American Maglev, Inc., Edgewater, FL (United States)
  2. BDM Federal, Inc., Huntsville, AL (United States)
  3. Argonne National Lab., IL (United States)
Publication Date:
OSTI Identifier:
186992
Report Number(s):
CONF-950404-
Journal ID: IEMGAQ; ISSN 0018-9464; TRN: IM9609%%265
Resource Type:
Journal Article
Journal Name:
IEEE Transactions on Magnetics
Additional Journal Information:
Journal Volume: 31; Journal Issue: 6Pt2; Conference: Conference on magnetism and magnetic materials, San Antonio, TX (United States), 18-21 Apr 1995; Other Information: PBD: Nov 1995
Country of Publication:
United States
Language:
English
Subject:
32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION; 33 ADVANCED PROPULSION SYSTEMS; LEVITATED TRAINS; MAGNET COILS; EDDY CURRENTS; TIME DEPENDENCE; MAGNETIC CIRCUITS; COMPUTERIZED SIMULATION; MAGNETS; CALCULATION METHODS

Citation Formats

Davey, K, Morris, T, Shaaf, J, and Rote, D. Calculation of motion induced eddy current forces in null flux coils. United States: N. p., 1995. Web. doi:10.1109/20.489930.
Davey, K, Morris, T, Shaaf, J, & Rote, D. Calculation of motion induced eddy current forces in null flux coils. United States. https://doi.org/10.1109/20.489930
Davey, K, Morris, T, Shaaf, J, and Rote, D. 1995. "Calculation of motion induced eddy current forces in null flux coils". United States. https://doi.org/10.1109/20.489930.
@article{osti_186992,
title = {Calculation of motion induced eddy current forces in null flux coils},
author = {Davey, K and Morris, T and Shaaf, J and Rote, D},
abstractNote = {Time dependent motion induced eddy current forces can be quite difficult to compute. The movement of null flux coils between magnets is approached using a coupled boundary element-circuit approach to compute the forces on the structure. The technique involves treating the magnets as a separate circuit whose current is dictated by the product of the magnet thickness and the working coercivity. The mutual inductance between the windows of the moving null flux coil and the stationary equivalent magnet coil hold the key for predicting lift, guidance, and drag forces on the coil. The rate of change of these inductances with respect to position determines the forces and currents. A steady state approximation to these forces is derived in addition to a numerical simulation when the steady state assumption is invalid. The results compare favorably to laboratory results from a 4 ft. diameter experimental test wheel.},
doi = {10.1109/20.489930},
url = {https://www.osti.gov/biblio/186992}, journal = {IEEE Transactions on Magnetics},
number = 6Pt2,
volume = 31,
place = {United States},
year = {Wed Nov 01 00:00:00 EST 1995},
month = {Wed Nov 01 00:00:00 EST 1995}
}