Efficiency Improvement by Loading Impedances for Dual feeding Magnetic Field Coupling WPT

In magnetic coupling wireless power transfer (WPT), the ability to transmit power in both directions from a single power transmission coil is a desirable feature, leveraging the generation of magnetic fields on both sides of the coil. This study investigates the impact of impedance loading on the coils used for magnetic field-coupled WPT, specifically focusing on a bi-directional simultaneous power supply. The aim is to optimize the reactance and capacitance values to maximize wireless power transmission efficiency at different distances between the coils: 10 mm, 75 mm, and 150 mm. The analysis reveals that the efficiency at a distance of 75 mm approaches the optimized value obtained at a distance of 10 mm.