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Loss and Efficiency Dependence of a 6.78 MHz, 100 W, 30 cm Distance Wireless Power Transfer System on Cable Types
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 Title & Authors
Loss and Efficiency Dependence of a 6.78 MHz, 100 W, 30 cm Distance Wireless Power Transfer System on Cable Types
Lee, Seung-Hwan; Lee, Byung-Song; Jung, Shin-Myung; Park, Chan-Bae;
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In MHz operating wireless power transfer systems, skin- and proximity-effect losses in the transmitter and the receiver coils dominate the coil-to-coil efficiency of the system. A Litz-wire was regarded as a common solution for minimizing such Ohmic losses in high frequencies. In this paper, equivalent series resistances of 12 different cables including Litz-wire and copper tubing have been calculated and measured for a 6.78 MHz, 100W, 30 cm wireless power transfer system. It has been shown that the copper tubing has lower resistances compared to the Litz-wire in that frequency and a wireless power transfer system with the copper tubing was able to achieve much higher efficiency than a system using the Litz-wire. Calculations of the resistances and efficiencies were accomplished with analytical equations and those calculations were evaluated by experimental results.
Wireless power transfer;inductive power transfer;copper loss;Litz-wire;copper tube;efficiency;
 Cited by
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S.-H. Lee, "Design methodologies for low flux density, high efficiency, kW level wireless power transfer systems with large air gaps," PhD Dissertation, University of Wisconsin-Madison, 2013.