A proposal of electromagnetic coupling for parallel line fed wireless power transfer

This paper proposes electromagnetic coupling for stabilizing the power transfer efficiency (PTE) of parallel line fed wireless power transfer (WPT). The conventional WPT system using magnetic coupled parallel line feeder suffers from PTE fluctuation due to magnetic field standing wave along the feeder line. Focusing on the fact that electric and magnetic fields are out of phase by 90 degrees, we propose a combination of electric and magnetic coupling to stabilize the PTE. In addition, load impedance is also optimized to Z-parameters of the system for further PTE enhancement. Numerical analysis confirmed effectiveness of the proposed electromagnetic coupling in stabilizing PTE for the WPT system.