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Calculation of shield of 50 Hz magnetic fields by OPERA/ELEKTRA

Abstract

The program OPERA/ELEKTRA of Vector Fields Ltd, Oxford, has been used for studies of shielding of 50 Hz magnetic fields, created by high currents in substation bus bars. A 3D finite element model (FEM) is used for analyzing the shielding effectiveness of an eddy current shield applied in the room of a 10/0.4 kV substation in order to reduce the flux density in an office situated above the substation. The influence of the shield extension is studied, and a calculated magnetic field attenuation of 30 dB is obtained for a 5 mm aluminum shield applied to the ceiling and the walls. The calculations have shown a strong geometry dependence of the magnetic shielding effectiveness at low frequencies. With a 3D model, the eddy current distribution in the shield can be studied, giving guidance for door positioning. The influence of shield conductivity is also analyzed
Authors:
Hamnerius, Y; Hasselgren, L; [1]  Moeller, E [2] 
  1. Chalmers Univ. of Technology, Gothenburg (Sweden). Dept. of Microwave Technology
  2. Linkoeping Univ. (Sweden). Dept. of Physics and Measurement Technology
Publication Date:
Sep 01, 1993
Product Type:
Technical Report
Report Number:
LITH-IFM-R-204
Reference Number:
SCA: 240400; PA: SWD-94:007133; EDB-94:063107; NTS-94:013785; SN: 94001180147
Resource Relation:
Other Information: PBD: Sep 1993
Subject:
24 POWER TRANSMISSION AND DISTRIBUTION; POWER SUBSTATIONS; MAGNETIC SHIELDING; MAGNETIC FIELDS; FINITE ELEMENT METHOD; EDDY CURRENTS; MATHEMATICAL MODELS; 240400; HEALTH AND SAFETY
OSTI ID:
10142882
Research Organizations:
Linkoeping Univ. (Sweden). Dept. of Physics and Measurement Technology
Country of Origin:
Sweden
Language:
English
Other Identifying Numbers:
Other: ON: DE94756507; TRN: SE9407133
Availability:
OSTI; NTIS
Submitting Site:
SWD
Size:
17 p.
Announcement Date:
Jul 05, 2005

Citation Formats

Hamnerius, Y, Hasselgren, L, and Moeller, E. Calculation of shield of 50 Hz magnetic fields by OPERA/ELEKTRA. Sweden: N. p., 1993. Web.
Hamnerius, Y, Hasselgren, L, & Moeller, E. Calculation of shield of 50 Hz magnetic fields by OPERA/ELEKTRA. Sweden.
Hamnerius, Y, Hasselgren, L, and Moeller, E. 1993. "Calculation of shield of 50 Hz magnetic fields by OPERA/ELEKTRA." Sweden.
@misc{etde_10142882,
title = {Calculation of shield of 50 Hz magnetic fields by OPERA/ELEKTRA}
author = {Hamnerius, Y, Hasselgren, L, and Moeller, E}
abstractNote = {The program OPERA/ELEKTRA of Vector Fields Ltd, Oxford, has been used for studies of shielding of 50 Hz magnetic fields, created by high currents in substation bus bars. A 3D finite element model (FEM) is used for analyzing the shielding effectiveness of an eddy current shield applied in the room of a 10/0.4 kV substation in order to reduce the flux density in an office situated above the substation. The influence of the shield extension is studied, and a calculated magnetic field attenuation of 30 dB is obtained for a 5 mm aluminum shield applied to the ceiling and the walls. The calculations have shown a strong geometry dependence of the magnetic shielding effectiveness at low frequencies. With a 3D model, the eddy current distribution in the shield can be studied, giving guidance for door positioning. The influence of shield conductivity is also analyzed}
place = {Sweden}
year = {1993}
month = {Sep}
}