Mutual Inductance Estimation for Constant Voltage Control of Wireless Power Transfer System under Frequency Splitting

In order to overcome the influence of frequency splitting and changes of coil position and load, a constant voltage control method based on mutual inductance estimation for the series and series (S-S) wireless power transfer (WPT) system is proposed in this paper. It can simply estimate the mutual inductance from the voltages and currents measured from the transmitter, which will be used for adaptively adjusting the system frequency and consequently guarantee a constant output voltage even under frequency splitting. Its effectiveness is then verified on a prototype WPT system.