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CLC number: TN721.2

On-line Access: 2010-08-02

Received: 2009-10-12

Revision Accepted: 2010-05-10

Crosschecked: 2010-07-16

Cited: 1

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Citations:  Bibtex RefMan EndNote GB/T7714

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Journal of Zhejiang University SCIENCE C 2010 Vol.11 No.8 P.629-636


Feedback analysis and design of inductive power links driven by Class-E amplifiers with variable coupling coefficients

Author(s):  Tian-liang Yang, Chun-yu Zhao, Da-yue Chen

Affiliation(s):  Institute of Intelligent Mechatronics Research, School of Electronic, Information and Electrical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China

Corresponding email(s):   tlyang@sjtu.edu.cn, dychen@sjtu.edu.cn

Key Words:  Inductive power link, Closed-loop Class-E amplifier, High efficient, Variable coupling coefficient

Tian-liang Yang, Chun-yu Zhao, Da-yue Chen. Feedback analysis and design of inductive power links driven by Class-E amplifiers with variable coupling coefficients[J]. Journal of Zhejiang University Science C, 2010, 11(8): 629-636.

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%T Feedback analysis and design of inductive power links driven by Class-E amplifiers with variable coupling coefficients
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%A Chun-yu Zhao
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%I Zhejiang University Press & Springer
%DOI 10.1631/jzus.C0910607

T1 - Feedback analysis and design of inductive power links driven by Class-E amplifiers with variable coupling coefficients
A1 - Tian-liang Yang
A1 - Chun-yu Zhao
A1 - Da-yue Chen
J0 - Journal of Zhejiang University Science C
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EP - 636
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PB - Zhejiang University Press & Springer
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DOI - 10.1631/jzus.C0910607

The efficiency of inductive power links driven by Class-E amplifiers may deteriorate due to variation in the coupling coefficient when the relative position of the radio frequency (RF) coils changes. To solve this problem, a new design methodology of power links is presented in this paper. The aim of the new design is to use the feedback signal, which is a phase difference between the driving signal and the output current of the Class-E amplifier, to adjust the duty cycle and angular frequency of the driving signal to maintain the optimum state of the inductive power link, and to adjust the supply voltage to keep the output power constant when the coupling coefficient of the RF coils changes. The parameter adjustments with respect to the coupling coefficient and the feedback signal are derived from the design equation of the inductive power link. To validate the feedback control rules, a prototype of the inductive power link was constructed, and its performance validated with the coupling coefficient set at 0.2 and a duty cycle of 0.5. The experimental results showed that, by adjusting the duty cycle, the angular frequency, and the supply voltage, the power link can be kept in optimal operation with a constant output power when the coupling coefficient changes from 0.2 to 0.1 to 0.25.

Darkslateblue:Affiliate; Royal Blue:Author; Turquoise:Article


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