Title |
Investigation of Shielding Effects of High Conductivity of High Permeability Materials on 60Hz ELF Magnetic Fields |
Authors |
송기현(Song Ki-Hyun) ; 명성호(Myung Sung-Ho) ; 민석원(Min Suk-Won) |
Abstract |
Shielding methods on ELF(Extremely Low Frequency) magnetic fields may include the use of induced currents, modification of magnetic field flux patterns using high permeability and/or high conductivity materials, and others. The magnetic shielding properties of enclosures can be utilized to reduce the magnetic field of current carrying conductors. In this paper, to get a more practical understanding of shielding phenomena, we have investigated the magnetic field reduction by means of 3 dimensional numerical analysis and experiments. We found copper could reduce flux density more then permalloy in both cases of box shield and cylindrical shield. Iron under l0μT of 1 phase could reduce flux density about 20 % more than silicon steel, but both of them under 50μT has a similar reduction rate of 10 %. The 3 phase horizontal model gave the highest reduction rate and the 1mm thickness iron under 10μT of 3 phase lines did lowest. |