Vol. 39

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Improvement of the Coupling Factor of Litz-Wire Coil Pair with Ferrite Substrate for Transcutaneous Energy Transfer System

By Lei Ke, Guozheng Yan, Sheng Yan, Zhiwu Wang, and Dasheng Liu
Progress In Electromagnetics Research M, Vol. 39, 41-52, 2014


This paper presents an optimized design of Litz-wire coil pair with ferrite substrates based on a set of analytical expressions and a 2-D finite-element analysis (FEA) in a way that the coupling coefficient is maximized. An investigation is made on key structure parameters of coils (e.g., structure of Litz-wire, number of turns, and number of layers) to determine their influence on self-inductance and mutual inductance respectively. The influence of ferrite substrate (e.g., relative permeability and thickness) is also considered. Different types of fabricated coils are used to verify all analytical expressions and optimization methods, and it is found that the theoretical predictions and simulations are in agreement with the measured results.


Lei Ke, Guozheng Yan, Sheng Yan, Zhiwu Wang, and Dasheng Liu, "Improvement of the Coupling Factor of Litz-Wire Coil Pair with Ferrite Substrate for Transcutaneous Energy Transfer System," Progress In Electromagnetics Research M, Vol. 39, 41-52, 2014.


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