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


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.


Supported by : 한국연구재단


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