Power Transfer Efficiency Calculation for Non-Contact Charger with Wire Coils in the 85-kHz Band

Power transfer efficiency was calculated for a non-contact charger system with wire coils in the 85-kHz band. Sending and receiving coils made from vinyl-insulated copper wire and litz wire were prepared and their power transfer efficiency was experimentally compared. The coil constants, namely the self- and mutual inductances and AC resistance, were calculated using the finite element method. The equations derived from the equivalent circuit for the non-contact charger system were solved using the Runge-Kutta method and then validated through a comparison with the experimental results.