Design and implementation of a modular wireless charging platform using magnetic resonance and beamforming?
Document typeMaster thesis
Rights access12 months embargo (embargoed until 2020-06-20T13:54:07Z)
Magnetic Resonance (MR) Wireless Power Transfer (WPT) is a specific case for thewell known inductive coupling principle where energy is transmitted from a transmittingcoil to a receiving one without the need of any wires. This technology brings enhancedcapabilities and offers the possibility to create cutting edge wireless charging systems. Theobjective of this thesis is to understand and develop the elements needed to build a MR WPT system capable of charging multiple wearable devices placed over a large surface.The focus is put in current and voltage sensing at high frequency for system monitor-ing; power amplifier topology design to maintain good performance across a range of loadvalues; and the beamforming and energy hopping applications validation to deal withcharging area coverage and transmission distance issues. The results show how the pres-ence of a receiver can be detected from the current change measured at the transmitter, aswell as voltage measurements are used as redundant information for system failure detec-tion; a class E power amplifier has been successfully designed to operate with loads thatdiffer 1 order of magnitude from each other; beamforming and energy hopping simulationenvironments have been set, and experiments have shown a 50% improve in the receivedsignal strength with the use of beamforming, while the enrgy hopping phenomena hasbeen empirically demonstrated for up to four hops along a planar array of coils. A solidbasis has been set to allow further development of the aimed wireless charging surface.