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Updated: Jul 14, 2026
12:18
Microwave Photonics Systems Based on Whispering-gallery-mode Resonators
Published on: August 5, 2013
Wireless power transfer via strongly coupled magnetic resonances
André Kurs1, Aristeidis Karalis, Robert Moffatt
1Department of Physics, Massachusetts Institute of Technology, Cambridge, MA 02139, USA. akurs@mit.edu
Science (New York, N.Y.)
|June 9, 2007
Summary
Researchers achieved efficient nonradiative power transfer using self-resonant coils, transmitting 60 watts over 2 meters with 40% efficiency. This demonstrates practical wireless power transfer over extended distances.
Area of Science:
- Electrical Engineering
- Physics
Background:
- Wireless power transfer (WPT) is crucial for modern electronics.
- Current WPT methods face limitations in range and efficiency.
Purpose of the Study:
- To demonstrate efficient nonradiative power transfer over significant distances.
- To develop and validate a quantitative model for this transfer.
Main Methods:
- Utilized self-resonant coils operating in a strongly coupled regime.
- Experimentally measured power transfer efficiency and distance.
- Developed a quantitative model to predict power transfer performance.
Main Results:
- Achieved efficient nonradiative power transfer up to 8 times the coil radius.
- Successfully transferred 60 watts with approximately 40% efficiency over distances exceeding 2 meters.
- The developed model accurately predicted experimental results within a 5% margin.
Conclusions:
- Demonstrated the feasibility of efficient, long-range wireless power transfer.
- The quantitative model provides a reliable tool for system design and analysis.
- The system shows practical applicability for various electronic devices and future research directions.
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