Adaptive Wireless Charging Using Resonant Coupling with Multiple Transmit Coils

We describe an experimental study of an mid-range resonant wireless power transfer (WPT) system with multiple transmit coils. While there exists substantial literature on WPT systems using coupled resonance as well as those using multi-coil transmitters, previous work has been limited to simple transmitter configurations with a small number of coils uncoupled with each other because of the difficulty of accurately tuning and optimizing such systems. Our key novelty is to use real-time receiver feedback to adaptively tune the system. This simple and powerful idea opens up the possibility of large-scale WPT systems with potentially large numbers of resonant transmitter coils that can adaptively transfer power to one or more receivers using realtime feedback. We describe a experimental study that shows the feasibility of this concept and its advantages over WPT systems without real-time feedback.