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Realization of Optimum Loads for Maximum WPT Efficiencies Using Multi-Turn Receiving Coil

수신 코일 권선 수 변화에 의한 무선전력전송 최적 부하 구현

  • Hwang, Sungyoun (Department of Electronics & Radio Engineering, Kyung Hee University) ;
  • Lee, Bomson (Department of Electronics & Radio Engineering, Kyung Hee University)
  • 황성연 (경희대학교 전자.전파공학과) ;
  • 이범선 (경희대학교 전자.전파공학과)
  • Received : 2016.01.07
  • Accepted : 2016.03.04
  • Published : 2016.04.30

Abstract

In this paper, we propose the method of controling the turns of a receiving coil for the matching directly to the receiver input impedance(typically $50{\Omega}$) with a maximum wireless power transfer(WPT) efficiency. Based on the presented the expression of the optimum load depending on a system figure of merit, number of the turns of a receiving coil, and proximity effect between conducting lines, the theoretical efficiencies have been compared with the measured ones with a good agreement. The results of this work may be used to realize a allowable maximum efficiency with a simple and low-profile 2-coil WPT system not requiring a separate feeding loop.

본 논문에서는 최대 무선전력전송 효율 구현에 필요한 최적 부하저항을 수신기 입력 임피던스(통상 $50{\Omega}$)에 바로 정합하기 위하여 수신 코일의 권선 수를 제어하는 방법을 제안한다. 수신 코일 권선 수와 도선 사이의 근접 효과가 고려된 최적 부하저항의 수식에 따라 수신 코일을 설계, 제작 및 측정하였다. 이론과 EM 시뮬레이션, 측정을 통하여 최적 부하 저항과 효율을 비교한 결과 비교적 잘 일치함을 확인할 수 있었다. 본 논문의 결과를 활용하면 별도의 급전 루프 없는 단순하고 부피가 작은 2-coil 시스템으로도 허용된 최대 전력을 구현할 수 있다.

Acknowledgement

Supported by : 한국연구재단

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