IMPEDANCE MATCHING FOR WIRELSS POWER TRANSFER

A wireless power transfer device may include a first circuit configured to be connected in series with a coil, a second circuit, and a switch, where switching a state of the switch may selectively couple the second circuit to the first circuit. The switch may be driven by a pulse width modulation (PWM) signal. The device may further include a PWM controller to receive measurements indicative of wireless power transferred through the coil, generate the PWM signal, and adjust the PWM signal to provide the wireless power transferred through the coil according to a selected metric.