Title |
Loss and Efficiency Dependence of a 6.78 MHz, 100 W, 30 cm Distance Wireless Power Transfer System on Cable Types |
Authors |
이승환(Lee, Seung-Hwan) ; 이병송(Lee, Byung-Song) ; 정신명(Jung, Shin-Myung) ; 박찬배(Park, Chan-Bae) |
DOI |
https://doi.org/10.5370/KIEE.2015.64.11.1651 |
Keywords |
Wireless power transfer ; inductive power transfer ; copper loss ; Litz-wire ; copper tube ; efficiency |
Abstract |
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. |