Transfer-power measurement: A non-contact method for fair and accurate metering of wireless power transfer in electric vehicles

Wireless power transfer is emerging as the preeminent way to charge electric vehicles, but there appears to be no fair way to measure power transfer. In this paper, transfer-power measurement (TPM) is introduced. TPM employs non-contact sensing elements to measure magnetic field from wireless power transfer and calculate the real power propagating through space. TPM provides fair metering because individual losses from the transmitter and receiver are disaggregated. Signal and data processing as well as a calibration method are discussed. Experimental results demonstrate a fair method of metering the real transfer power with low estimation error. Fair metering incentivizes businesses and individuals to make choices that conserve energy and advance technology by providing more information and by properly assigning the financial loss.