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Title: Passive shielding effect on space profile of magnetic field emissions for wireless power transfer to vehicles

Abstract

Magnetic fields emitted by wireless power transfer systems are of high importance with respect to human safety and health. Aluminum and ferrite are used in the system to reduce the fields and are termed as passive shielding. In this paper, the influence of these materials on the space profile has been investigated with the help of simulations on Comsol for the four possible geometries—no shielding, ferrite, aluminum, and full shielding. As the reflected impedance varies for the four geometries, the primary current is varied accordingly to maintain constant power transfer to the secondary side. Surrounding magnetic field plots in the vertical direction show that maxima's of the two coils for the no shielding geometry are centered at the respective coils and for the remaining three are displaced closer to each other. This closeness would lead to more effective addition of the two coil fields and an increase in the resultant field from space point of view. This closeness varies with distance in the horizontal direction and vertical gap between the coils and is explained in the paper. This paper provides a better understanding of effect of the passive shielding materials on the space nature of magnetic fields for wireless powermore » transfer for vehicle applications.« less

Authors:
;  [1]
  1. Department of Energy Technology, Aalborg University, Aalborg 9220 (Denmark)
Publication Date:
OSTI Identifier:
22409931
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 117; Journal Issue: 17; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ALUMINIUM; C CODES; COMPUTERIZED SIMULATION; EMISSION; FERRITES; IMPEDANCE; MAGNET COILS; MAGNETIC FIELDS; POWER TRANSMISSION; SHIELDING; SHIELDING MATERIALS

Citation Formats

Batra, T., E-mail: tba@et.aau.dk, and Schaltz, E. Passive shielding effect on space profile of magnetic field emissions for wireless power transfer to vehicles. United States: N. p., 2015. Web. doi:10.1063/1.4916930.
Batra, T., E-mail: tba@et.aau.dk, & Schaltz, E. Passive shielding effect on space profile of magnetic field emissions for wireless power transfer to vehicles. United States. doi:10.1063/1.4916930.
Batra, T., E-mail: tba@et.aau.dk, and Schaltz, E. Thu . "Passive shielding effect on space profile of magnetic field emissions for wireless power transfer to vehicles". United States. doi:10.1063/1.4916930.
@article{osti_22409931,
title = {Passive shielding effect on space profile of magnetic field emissions for wireless power transfer to vehicles},
author = {Batra, T., E-mail: tba@et.aau.dk and Schaltz, E.},
abstractNote = {Magnetic fields emitted by wireless power transfer systems are of high importance with respect to human safety and health. Aluminum and ferrite are used in the system to reduce the fields and are termed as passive shielding. In this paper, the influence of these materials on the space profile has been investigated with the help of simulations on Comsol for the four possible geometries—no shielding, ferrite, aluminum, and full shielding. As the reflected impedance varies for the four geometries, the primary current is varied accordingly to maintain constant power transfer to the secondary side. Surrounding magnetic field plots in the vertical direction show that maxima's of the two coils for the no shielding geometry are centered at the respective coils and for the remaining three are displaced closer to each other. This closeness would lead to more effective addition of the two coil fields and an increase in the resultant field from space point of view. This closeness varies with distance in the horizontal direction and vertical gap between the coils and is explained in the paper. This paper provides a better understanding of effect of the passive shielding materials on the space nature of magnetic fields for wireless power transfer for vehicle applications.},
doi = {10.1063/1.4916930},
journal = {Journal of Applied Physics},
number = 17,
volume = 117,
place = {United States},
year = {Thu May 07 00:00:00 EDT 2015},
month = {Thu May 07 00:00:00 EDT 2015}
}
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