Vol. 70

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Study on the Vibration Mechanism of the Relay Coil in a Three-Coil WPT System

By Suqi Liu and Jianping Tan
Progress In Electromagnetics Research M, Vol. 70, 117-126, 2018


Wireless power transfer (WPT) via coupled magnetic resonances has been in development for over a decade. Frequency splitting occurs in the over-coupled region. In addition, the vibration of the receiver and relay coils is observed in the over-coupled region. The vibration mechanism of the relay coil is investigated in this study. First, the circuit model of a three-coil WPT system is established, and the transfer characteristics of the system are examined by applying circuit theories. Second, the transfer characteristics of the three-coil WPT system are analyzed using simulation software. Third, the energy equation of state of the three-coil WPT system is established with the introduction of entropy variable. Lastly, the experimental circuit of the three-coil WPT system is designed. The experimental results are consistent with the theoretical analysis. The vibration of the relay coil is clearly explained. The transfer characteristics of the three-coil WPT system, particularly the relay coil, may provide ideas to achieve the maximum output power and transmission efficiency under various operating conditions.


Suqi Liu and Jianping Tan, "Study on the Vibration Mechanism of the Relay Coil in a Three-Coil WPT System," Progress In Electromagnetics Research M, Vol. 70, 117-126, 2018.


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