IDEAS home Printed from https://ideas.repec.org/a/gam/jeners/v18y2025i6p1329-d1608051.html
   My bibliography  Save this article

A Long-Range, High-Efficiency Resonant Wireless Power Transfer via Imaginary Turn Ratio Air Voltage Transformer

Author

Listed:
  • Hsien-Chung Tang

    (Department of Mechanical Engineering, College of Engineering, National Yang-Ming Chiao-Tung University, Hsinchu 30010, Taiwan)

  • Chun-Hao Chen

    (Department of Material Science and Engineering, International College of Semiconductor Technology, National Yang-Ming Chiao-Tung University, Hsinchu 30010, Taiwan)

  • Edward-Yi Chang

    (Department of Material Science and Engineering, International College of Semiconductor Technology, National Yang-Ming Chiao-Tung University, Hsinchu 30010, Taiwan)

  • Da-Jeng Yao

    (Department of Power Mechanical Engineering, College of Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan)

  • Wei-Hua Chieng

    (Department of Mechanical Engineering, College of Engineering, National Yang-Ming Chiao-Tung University, Hsinchu 30010, Taiwan)

  • Jun-Ying He

    (Department of Mechanical Engineering, College of Engineering, National Yang-Ming Chiao-Tung University, Hsinchu 30010, Taiwan)

Abstract

This paper presents a resonant wireless power transfer method that leverages a 90-degree voltage phase shift between the transmitting and receiving coils to enhance efficiency and maximize power transfer. When the resonant coupling is achieved, the secondary coil with an adjustable capacitor forms a tuned LC circuit. If the primary coil is driven at the resonant frequency of both the primary and secondary sides, the system can transmit 250W of power between the coils over a distance of 50 cm. Using a single power transmitting unit (PTU) board with multiple paralleled gallium nitride high-electron-mobility transistors (GaN HEMTs), the system achieves a maximum power transfer efficiency of 88%, highlighting the effectiveness of the design in high-efficiency, long-distance wireless power transmission. The key to the success of high-power, high-efficiency RWPT is in exhibiting the imaginary turn ratio presented on the air transformer. The imaginary turn ratio can realize the negative impedance conversion that converts the positive resistance on the power-receiving unit into a negative one, and thus, the damping of the resonance oscillation becomes negative and positively encourages more power to be delivered to the power-receiving unit (PRU) load. This paper derives the theory of the imaginary turn ratio and demonstrates the implementation of the RWPT system that exhibits the imaginary turn ratio effect.

Suggested Citation

  • Hsien-Chung Tang & Chun-Hao Chen & Edward-Yi Chang & Da-Jeng Yao & Wei-Hua Chieng & Jun-Ying He, 2025. "A Long-Range, High-Efficiency Resonant Wireless Power Transfer via Imaginary Turn Ratio Air Voltage Transformer," Energies, MDPI, vol. 18(6), pages 1-21, March.
    • Handle: RePEc:gam:jeners:v:18:y:2025:i:6:p:1329-:d:1608051
    as

    Download full text from publisher

    File URL: https://www.mdpi.com/1996-1073/18/6/1329/pdf
    Download Restriction: no
    File URL: https://www.mdpi.com/1996-1073/18/6/1329/
    Download Restriction: no
    ---><---

    References listed on IDEAS

    as
    1. You-Chen Weng & Chih-Chiang Wu & Edward Yi Chang & Wei-Hua Chieng, 2021. "Minimum Power Input Control for Class-E Amplifier Using Depletion-Mode Gallium Nitride High Electron Mobility Transistor," Energies, MDPI, vol. 14(8), pages 1-16, April.
    Full references (including those not matched with items on IDEAS)

    Most related items

    These are the items that most often cite the same works as this one and are cited by the same works as this one.
    1. Chih-Chiang Wu & Ching-Yao Liu & Guo-Bin Wang & Yueh-Tsung Shieh & Wei-Hua Chieng & Edward Yi Chang, 2021. "A New GaN-Based Device, P-Cascode GaN HEMT, and Its Synchronous Buck Converter Circuit Realization," Energies, MDPI, vol. 14(12), pages 1-23, June.
    2. Ching-Yao Liu & Chih-Chiang Wu & Li-Chuan Tang & Yueh-Tsung Shieh & Wei-Hua Chieng & Edward-Yi Chang, 2023. "Resonant Mechanism for a Long-Distance Wireless Power Transfer Using Class E PA and GaN HEMT," Energies, MDPI, vol. 16(9), pages 1-21, April.
    3. Chih-Chiang Wu & Ching-Yao Liu & Sandeep Anand & Wei-Hua Chieng & Edward-Yi Chang & Arnab Sarkar, 2021. "Comparisons on Different Innovative Cascode GaN HEMT E-Mode Power Modules and Their Efficiencies on the Flyback Converter," Energies, MDPI, vol. 14(18), pages 1-26, September.
    4. Li-Chuan Tang & Shyr-Long Jeng & Edward-Yi Chang & Wei-Hua Chieng, 2021. "Variable-Frequency Pulse Width Modulation Circuits for Resonant Wireless Power Transfer," Energies, MDPI, vol. 14(12), pages 1-25, June.
    5. Yueh-Tsung Shieh & Chih-Chiang Wu & Shyr-Long Jeng & Ching-Yao Liu & Shiang-Yu Hsieh & Chi-Chun Haung & Wen-Yuh Shieh & Wei-Hua Chieng & Edward-Yi Chang, 2023. "A Turn-Ratio-Changing Half-Bridge CLLC DC–DC Bidirectional Battery Charger Using a GaN HEMT," Energies, MDPI, vol. 16(16), pages 1-28, August.
    6. Yueh-Tsung Shieh & Ching-Yao Liu & Chih-Chiang Wu & Wei-Hua Chieng & Edward-Yi Chang, 2022. "Flyback Converter Using a D-Mode GaN HEMT Synchronous Rectifier," Energies, MDPI, vol. 15(9), pages 1-21, April.
    7. Rustam Kumar & Chih-Chiang Wu & Ching-Yao Liu & Yu-Lin Hsiao & Wei-Hua Chieng & Edward-Yi Chang, 2021. "Discontinuous Current Mode Modeling and Zero Current Switching of Flyback Converter," Energies, MDPI, vol. 14(18), pages 1-23, September.

    Corrections

    All material on this site has been provided by the respective publishers and authors. You can help correct errors and omissions. When requesting a correction, please mention this item's handle: RePEc:gam:jeners:v:18:y:2025:i:6:p:1329-:d:1608051. See general information about how to correct material in RePEc.

    If you have authored this item and are not yet registered with RePEc, we encourage you to do it here. This allows to link your profile to this item. It also allows you to accept potential citations to this item that we are uncertain about.

    If CitEc recognized a bibliographic reference but did not link an item in RePEc to it, you can help with this form .

    If you know of missing items citing this one, you can help us creating those links by adding the relevant references in the same way as above, for each refering item. If you are a registered author of this item, you may also want to check the "citations" tab in your RePEc Author Service profile, as there may be some citations waiting for confirmation.

    For technical questions regarding this item, or to correct its authors, title, abstract, bibliographic or download information, contact: MDPI Indexing Manager (email available below). General contact details of provider: https://www.mdpi.com .

    Please note that corrections may take a couple of weeks to filter through the various RePEc services.

    IDEAS is a RePEc service. RePEc uses bibliographic data supplied by the respective publishers.