Reconfigurable Wireless Power Transfer Systems for Distance Adaptation

High efficiency power transfer in a magnetically coupled resonant wireless power transfer (MCR-WPT) system is only happened at a specific distance. In most applications, the distance between the transmitter and the receiver could be changed. To overcome this boundary, a reconfigurable three coil wireless power transfer system is proposed in this paper to maintain high power transfer efficiency over a long distance. The repeater coil consists of switches which are used to adjust the coupling coefficient and improve the transmission quality according to the change of distance between the transmitter and receiver. The principle of this reconfigurable structure is explained with the theoretical analysis and verified with experimental measurements.