A Circuit Model-Based Analysis of Magnetically Coupled Resonant Loops in Wireless Power Transfer Systems

Year 2018, Volume: 18 Issue: 2, 159 - 166, 03.08.2018

Seyit Ahmet Sis

Abstract

DOI: 10.26650/electrica.2018.55345

Magnetically coupled resonant loops can be represented by a lumped element circuit model. Each parameter in the lumped element model can be expressed as a function of loop geometry and the separation between the loops; therefore, the geometry can be systematically changed, and the power transfer efficiency of the coupled loops can be predicted. This paper presents a simulation-based efficiency analysis for wireless power transfer systems utilizing magnetically coupled resonant loops. The behavior of power transfer efficiency is studied for various loop geometry parameters, and the simulation results are presented in detail. These results clearly show that there is a trade-off between peak efficiency and critical coupling distance, both of which depend on the loop size, frequency of operation, and source-load impedances. To verify the accuracy model, two identical circular loops are fabricated and measured, and the measurement results agree well with the model. 

Keywords

Wireless power transfer systems, magnetically coupled loops, power transfer efficiency

A Circuit Model-Based Analysis of Magnetically Coupled Resonant Loops in Wireless Power Transfer Systems

Abstract

DOI: 10.26650/electrica.2018.55345

Magnetically coupled resonant loops can be
represented by a lumped element circuit model. Each parameter in the lumped
element model can be expressed as a function of loop geometry and the
separation between the loops; therefore, the geometry can be systematically
changed, and the power transfer efficiency of the coupled loops can be
predicted. This paper presents a simulation-based efficiency analysis for
wireless power transfer systems utilizing magnetically coupled resonant loops.
The behavior of power transfer efficiency is studied for various loop geometry
parameters, and the simulation results are presented in detail. These results
clearly show that there is a trade-off between peak efficiency and critical
coupling distance, both of which depend on the loop size, frequency of
operation, and source-load impedances. To verify the accuracy model, two
identical circular loops are fabricated and measured, and the measurement
results agree well with the model. 

Keywords

Wireless power transfer systems, magnetically coupled loops, power transfer efficiency

References

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