Characteristics of Magnetic Resonance Wireless Power Transfer Across Gap Distance Using Metallic Wire Coils

Significant progress has been made in the area of wireless power transfer (WPT) during the last few years. Large air gaps can now be crossed using power, according to recent research. WPT was used at the small scale, such as in mobile phones, before its proposal for use in large-scale electric equipment such as electric vehicles. Furthermore, it is planned that all electrical cords will be replaced with WPT units. Electric resonance coupling enables high-efficiency power transmission across large air gaps. This has been used in communication technology antennas and resonators and is closely connected to electromagnetic induction. In contrast to coupled mode theory, equivalent circuits-a topology more familiar to electrical engineers-are used in this study to investigate power transfer phenomena and technologies. By combining various combinations of coils for the transmitter (Tx) and receiver (Rx), it should be possible to increase the gap between the coils. Therefore, a pair of Tx and Rx coils is analyzed by computer simulation and lab experiments to measure the voltage and current received by the Rx module. The result for a 14 cm gap between the coils shows that the designed module can transmit power wirelessly over a medium-distance gap.