Alternative Expressions for Mutual Inductance and Coupling Coefficient Applied in Wireless Power Transfer

Title & Authors
Alternative Expressions for Mutual Inductance and Coupling Coefficient Applied in Wireless Power Transfer
Kim, Gunyoung; Lee, Bomson;

Abstract
Alternative analytic expressions for the mutual inductance ($\small{L_m}$) and coupling coefficient (k) between circular loops are presented using more familiar and convenient expressions that represent the property of reciprocity clearly. In particular, the coupling coefficients are expressed in terms of structural dimensions normalized to a geometric mean of radii of two loops. Based on the presented expressions, various aspects of the mutual inductances and coupling coefficients, including the regions of positive, zero, and negative value, are examined with respect to their impacts on the efficiency of wireless power transmission.
Keywords
Coupling Coefficient;Magnetic Flux;Mutual Inductance;Transfer Efficiency;Wireless Power Transfer;
Language
English
Cited by
1.
An Effective Experimental Optimization Method for Wireless Power Transfer System Design Using Frequency Domain Measurement, Journal of Electromagnetic Engineering and Science, 2017, 17, 4, 208
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