Affiliations: [a] State Key Laboratory of Power Transmission Equipment
& System Security and New Technology, School of Electrical Engineering,
Chongqing University, Chongqing, China | [b] Dongfang Electrical Machinery Company Co., LTD,
Sichuan Deyang, China
Correspondence:
[*]
Corresponding author: Fan Yang, This study is supported by
National '111' project (B08036), the State Key Laboratory project
(2007DA10512709102) and the National College Students Innovation project
(091061106). Tel.: +86 23 65106977; E-mail: [email protected]
Abstract: The magnetic field (MF) produced by the bus bars in the urban
distribution substation can pollute the environment, and shielding measures
should be taken. In the paper the model to calculate the power frequency
magnetic field around an urban distribution substation is presented firstly,
then the calculation on the magnetic field produced by the three-phase bus bars
was carried out, and influence on the magnetic field distribution caused by
different parameter was analyzed. The results indicate that to decrease the
magnetic field in the upper floor, it's better to make the distance between the
bus bars within 0.4 m, and the height of the bus bars within 0.1 m. Then the
shielding measures to eliminate the magnetic field in the upper floor
residential housing were investigated, and results indicate that the smaller
size of the reinforced grid and the greater diameter of the reinforced bar, the
better is the shielding effectiveness. For the shielding of the magnetic field
in the up floors, the shielding effectiveness can reach 33.52 dB with an 8 mm
thick shielding steel plate used in the floorboard. Considering the economic
cost, the shielding grid made of 8# reinforced bars (net size:
0.10*0.10 m^{2}, the diameter of the reinforced bar is 8 mm)
is the best for the MF shielding.
Keywords: Magnetic field, distribution substation, bus bar, shielding, concrete and reinforced grid
