The Journal of Korean Institute of Electromagnetic Engineering and Science (한국전자파학회논문지)

The Korean Institute of Electromagnetic Engineering and Science (한국전자파학회)
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Analysis of Electromagnetic Wave Exposure Due to 6.78 MHz Wireless Power Transfer System

6.78 MHz 무선전력전송 시스템에 의한 전자파 노출량 분석

  • Yoon, Seok (School of Electronics and Computer Engineering, Chonnam National University) ;
  • Jung, Hyeonjong (School of Electronics and Computer Engineering, Chonnam National University) ;
  • Lim, Yeongseog (School of Electronics and Computer Engineering, Chonnam National University)
  • 윤석 (전남대학교 전자컴퓨터공학부) ;
  • 정현종 (전남대학교 전자컴퓨터공학부) ;
  • 임영석 (전남대학교 전자컴퓨터공학부)
  • Received : 2017.08.22
  • Accepted : 2017.12.18
  • Published : 2017.12.29
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Abstract

In this paper, we analyzed the electric/magnetic field distribution and SAR distribution in a human body due to the resonant-type wireless power transfer(WPT) system with an operating frequency of 6.78 MHz. To analyze the field distribution under the unperturbed condition, a prototype system was fabricated and the measured results were compared with the simulation results. For safety during measurement, the available power to the transmitter coil is limited to 1 W. To analyze the induced current density and SAR distribution, a simple human model consisting of three layers, skin, fat, and muscle, was used for the simulation. The electromagnetic wave exposure levels obtained through measurement and simulation were compared with the recommended levels by the ICNIRP.

본 연구에서는 공진형 무선전력전송시스템에 의해 발생되는 자기장과 전기장 강도 및 이에 의한 인체 내부 전자파 비흡수율(Specific Absorption Rate: SAR) 분포를 분석하였다. 연구에서 사용된 동작주파수는 ISM 대역에 해당하는 6.78 MHz이다. 실제 시스템을 제작하고, 시스템의 송신측에 공급되는 가용 전력을 1 W로 제한하여 전기장 및 자기장 분포를 측정하고, 동일한 규격으로 시뮬레이션한 결과와 비교하였다. 피부, 지방, 근육의 순으로 조직층이 구성된 단순인체모델을 이용하여, WPT 시스템으로부터의 거리에 따른 인체 내부의 유도 전류밀도와 SAR 분포를 구하였다. 측정과 시뮬레이션을 통해 얻어진 전자파 노출 정도를 ICNIRP(International Commission on Non-Ionizing Radiation Protection)의 국제 권고기준과 비교하여 분석하였다.

Keywords

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