A Study on Fingerprint-Based Coil Alignment Improvement Technique for Magnetic Resonant Wireless Power Transfer System

핑거프린트 방식의 자기 공진형 무선전력전송 코일 정렬 상태 개선 기법 연구

  • Kim, Sungjae (Department of Electronics, Information and Communication Engineering, Konkuk University) ;
  • Lee, Euibum (Department of Electronics, Information and Communication Engineering, Konkuk University) ;
  • Ku, Hyunchul (Department of Electronics, Information and Communication Engineering, Konkuk University)
  • 김성재 (건국대학교 전자정보통신공학과) ;
  • 이의범 (건국대학교 전자정보통신공학과) ;
  • 구현철 (건국대학교 전자정보통신공학과)
  • Received : 2018.11.19
  • Accepted : 2019.01.18
  • Published : 2019.01.31


This paper proposes fingerprint-based positioning methods which can be used in a magnetic resonant wireless power transfer(WPT) system and verifies their performance. A new receiver coil with small orthogonal auxiliary coils is proposed to measure magnetic field signals in three axial directions. The magnitude and phase characteristics of the three-axis electromotive force can be obtained by using the proposed coil. To predict a position with the measured values, we propose a lookup table-based method and linear discriminant analysis-based method. For verification, the proposed methods are applied to predict 75 positions of the 6.78 MHz WPT system, and the performances such as accuracy and computation time are compared.


Positioning Method;Machine Learning;Wireless Power Transfer;Time-Varying Magnetic Field

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그림 1. 제안하는 수신 코일의 형태 Fig. 1. The configuration of the proposing Rx coil.

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그림 2. 제안하는 시스템의 회로도 Fig. 2. Schematic of the proposing system.

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그림 3. 제안한 코일에서 측정된 3축 기전력 Fig. 3. Measured 3-axis electromotive force in the proposed coil.

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그림 4. 측위 과정 예시 (LUT 기반) Fig. 4. Example of positioning process (LUT based).

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그림 5. 제안하는 측위 진행도 Fig. 5. The progress of the proposed positioning methods.

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그림 6. 제작한 송신 코일과 수신 코일 Fig. 6. Fabricated Tx coil and Rx coil.

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그림 7. 실험 환경 Fig. 7. Experimental environment.

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그림 8. 코일 타입별 파라미터 Fig. 8. The parameters of each coil type.

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그림 9. 각 요소별 측정 결과 Fig. 9. The measurement results of each attribute.

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그림 10. 측위 결과에 따른 오차 분포 Fig. 10. Error distribution according to positioning result.

표 1. 각 코일별 정보 Table 1. Specification of each coil.

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표 2. 제안 기법의 정확도와 처리 속도 Table 2. Accuracy and processing time of the proposed me-thods.

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Supported by : 한국연구재단, 건국대학교


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