CAPACITIVE WIRELESS POWER TRANSFER BY MEANS OF ADAPTIVE MATCHING NETWORKS

A controlled wireless Capacitive Power Transfer (CPT) system includes a primary side for wirelessly transmitting power to a secondary side via coupling plates having mutual capacitance C. A primary adaptive matching network regulates the current flowing to the secondary side. A primary controller includes a first control loop for adjusting the switching frequency fto compensate for changes in the impedance of the primary matching network. A second control loop adjusts the resonant frequency of the primary resonant circuit to track the switching frequency f. A secondary adaptive matching network is comprised of a secondary resonant circuit with a bias-controlled variable secondary inductor serially connected to the mutual capacitance Cand a capacitor parallelly connected to the mutual capacitance C, for matching the impedance of the secondary matching network. A secondary controller adjusts the impedance of the secondary matching network to match the resonant frequency of the primary resonant circuit.