Progress In Electromagnetics Research
ISSN: 1070-4698, E-ISSN: 1559-8985
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By G. K. Sessel and I. W. Hofsajer

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The focusing of a magnetic field, at low frequencies, in the very near field is difficult as flux lines naturally tend to disperse. It is not possible to use antenna array techniques due to large wavelengths at low frequencies. A method for synthesizing a concentrated magnetic field in a large air gap between two magnetic poles is presented. The focusing effect is brought about by the inclusion of side poles, adjacent to each of the main poles. Through the correct dimensioning of the side poles' reluctances and relative magneto-motive forces it is possible to focus the field in the center of the gap. General design curves for normalized parameters, determined via finite element modelling, are presented. A scale model is experimentally verified.

G. K. Sessel and I. W. Hofsajer, "Synthesis of a Magnetic Field Concentrated in One Dimension," Progress In Electromagnetics Research, Vol. 144, 141-150, 2014.

1. Nacev, A., et al., "Towards control of magnetic fluids in patients: Directing therapeutic nanoparticles to disease locations ," IEEE Control Systems, Vol. 32, No. 3, 32-74, 2012.

2. Dede, E. M., J. Guo, Y. Lee, L. Q. Zhou, M. Zhang, and D. Banerjee, "Kilohertz magnetic field focusing and force enhancement using metalic loop array," Applied Physics Letters, Vol. 101, 023506-4, 2012.

3. Lee, J., E. M. Banerjee, D. Dede, and H. Iizuka, "Magnetic force enhancement in a linear actuator by air-gap magnetic field distribution optimisation and design," Finite Elements in Analysis and Design, Vol. 58, 44-52, 2012.

4. Alexiou, C., et al., "A high field gradient magnet for magnetic drug targeting," IEEE Transactions on Applied Superconductivity, Vol. 16, No. 2, 1527-1530, 2006.

5. Han, X., Q. Cao, and L. Li, "Design and evaluation of three-dimensional electromagnetic guide system for magnetic drug delivery," IEEE Transactions on Applied Superconductivity, Vol. 22, No. 3, 4401404, 2012.

6. Sessel, G. K., "A technique for the production of a high amplitude, high frequency, concentrated magnetic field for use in hyperthermia applications," Dissertation, University of Witwatersrand, 2012.

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