L-type impedance matching circuits (IMCs) can maximize the power transfer efficiency (PTE) by converting the load to the optimum one in the wireless power transfer system. However, their effectiveness is inadequately studied. In this work, the applicability of the L-type IMCs is carefully examined under the restriction of capacitance realization. The sensitivities with respect to the deviation of the capacitance in mass production as well as the variations of the load and the mutual inductance are analyzed in detail and validated by experiments. By comparison with the basic-type IMCs, the L-type IMCs have higher, nearly equal and lower sensitivities with respect to the deviation of the capacitance, the variation of the load, and the variation of the mutual inductance, respectively.
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