A simple theory for optimizing finite width ELF magnetic field shields for minimum dependence on source orientation

Author

Moreno, Pablo ; Olsen, Robert G.

Author_Institution

Dept. of Electr. Eng. & Comput. Sci., Washington State Univ., Pullman, WA, USA

Volume

39

Issue

4

fYear

1997

fDate

11/1/1997 12:00:00 AM

Firstpage

340

Lastpage

348

Abstract

The effectiveness of single layer, finite width, planar extremely low frequency (ELF) magnetic field shields is strongly dependent upon the orientation of the field sources. Since source information is difficult to obtain, the issue of designing shields which are independent of source orientation is important. Here, a simple analytic model for shielding by multiple layer, finite width, planar shields constructed from perfect electric and perfect magnetic material is presented. This is augmented by a study of conditions for which the perfect material approximation is valid. The simple model is used to determine strategies for designing shields which are independent of source orientation. It is found that two layer perfect electric/magnetic shields perform significantly better than single layer shields

Keywords

conducting materials; magnetic materials; magnetic shielding; optimisation; ELF magnetic field shields; analytic model; field source orientation; finite width magnetic field shields; perfect electric material; perfect magnetic material; perfect material approximation; single layer planar magnetic field shields; source information; source orientation; Boundary conditions; Conducting materials; Frequency; Geophysical measurement techniques; Ground penetrating radar; H infinity control; Magnetic analysis; Magnetic materials; Magnetic shielding; Protection;

fLanguage

English

Journal_Title

Electromagnetic Compatibility, IEEE Transactions on

Publisher

ieee

ISSN

0018-9375

Type

jour

DOI

10.1109/15.649828

Filename

649828