The Transactions of The Korean Institute of Electrical Engineers (전기학회논문지)

The Korean Institute of Electrical Engineers (대한전기학회)
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Characteristics of Wireless Power Transmission Using Superconductor Coil to Improve the Efficiency According to the Shielding Materials

초전도 공진 코일의 효율성을 높이기 위한 차폐 재질에 따른 무선전력전송 효율비교 분석

  • Received : 2016.03.11
  • Accepted : 2016.03.28
  • Published : 2016.04.01
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Abstract

The magnetic resonance method requires high quality factor(Q-factor) of resonators. Superconductor coils were used in this study to increase the Q-factor of wireless power transfer(WPT) systems in the magnetic resonance method. The results showed better transfer efficiency compared to copper coils. However, as superconducting coils should be cooled below critical temperatures, they require cooling containers. In this viewpoint, shielding materials for the cooling containers were applied for the analysis of the WPT characteristics. The shielding materials were applied at both ends of the transmitter and receiver coils. Iron, aluminum, and plastic were used for shielding. The electric field distribution and S-parameters (S11, S21) of superconducting coils were compared and analyzed according to the shield materials. As a result, plastic shielding showed better transfer efficiency, while iron and aluminum had less efficiency. Also, the maximum magnetic field distribution of the coils according to the shielding materials was analyzed. It was found that plastic shielding had 5 times bigger power transfer rate than iron or aluminum. It is suggested that the reliability of superconducting WPT systems can be secured if plastic is used for the cooling containers of superconducting resonance coils.

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References

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