A shunt-excited inductive power link.

K Sylvan; J R Jordan; H W Whittington

doi:10.3109/03091908909015408

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A shunt-excited inductive power link.

K Sylvan·J R Jordan·H W Whittington

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Abstract

An alternative derivation of the separation-insensitive property of series-excited self-oscillating inductive power transfer circuits is presented. This analysis is based on network theory and does not include the explicit determination of frequency as a step in the derivation. The separation-insensitivity principle is extended to shunt-excited links which exhibit a theoretical voltage transfer function of unity while the coupling factor exceeds the reciprocal of the secondary quality factor. This requires the inclusion of a series resistor in the primary resonator's capacitive arm. Series RC elements are replaced by parallel forms in both the primary and secondary; this provides a more convenient output impedance level without the need for another transformer. A demonstration circuit is described and tested. It is found that separation-insensitivity occurs while the coupling factor exceeds the reciprocal of the loaded secondary quality factor. Somewhat inferior response is obtained from a simpler circuit having no added resistances in the primary.

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K Sylvan, J R Jordan, H W Whittington. A shunt-excited inductive power link.. https://doi.org/10.3109/03091908909015408

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