On the use of conical helix inductors in wireless power transfer systems

An efficient magnetically coupled wireless power transfer system using a conical coil structure is presented. The use of conical inductors instead of traditional planar coils increases the self-resonance frequency of the transmitter resonator while maintaining the flux linkage to the receiver side. Electromagnetic (EM) and circuit simulation results predict an increase in the efficiency achieved by such wireless power transfer links as compared to systems that use planar inductors. The measurement results of a prototype three-coil structure built based on the conical structure confirm the validity of simulation results.