A Wireless Charging Coil in Printed Circuit Board with Partially Split Conductors for Low Resistance

The paper proposed a PCB type coil with partially split conductors which have reduced resistance compared to a conventional PCB type coil. In order to design the proposed PCB type coil, a position where the resistance per unit length is relatively large in the conventional PCB type coil was analyzed by calculation. Then we analyzed total resistance of the PCB type coils according to the number of divided conductors by calculation. The PCB type coil with a proposed design was fabricated for measurement. Resistance of each coil was measured using a vector network analyzer. Experiment results show that the proposed PCB type coil has resistance reduced by 28% compared to the conventional PCB type coil. In addition, results of circuit simulation show that when the proposed PCB type coils are used to 15 W class wireless power transfer system, the efficiency increased by 5.2 % compared to the conventional coils.