Electric field coupling technique of wireless power transfer for electric vehicles

An electric-field coupling wireless-power-transfer technique is proposed based on the concept of impedance matching. In the proposed electric-field coupling technique, the impedance matching can be easily achieved by controlling the matching inductance. Also, the shielding of the electric field is easy. A metallic plate implemented at the bottom surface of a vehicle is proposed to maximize the coupling capacitance. A simplified experimental setup has been developed, and the maximum power transfer efficiency of about 78% has been measured.