AUTO RESONANT DRIVER FOR WIRELESS POWER TRANSMITTER SENSING REQUIRED TRANSMIT POWER FOR OPTIMUM EFFICIENCY

A power transmission system for wirelessly supplying power to a load comprising a transmitter inductor, a first switch coupled between a voltage source and the transmitter inductor and controlled to generate a varying current through the transmitter inductor, a receiver inductor magnetically coupled to the transmitter inductor, a voltage regulator receiving power from the receiver inductor to generate a regulator output voltage, a load coupled to an output of the voltage regulator, wherein power in the transmitter inductor is wirelessly coupled to the receiver inductor for being converted to a regulated voltage by the regulator for driving the load, a peak voltage detector coupled to detect a peak voltage on the transmitter inductor, wherein a peak voltage on the transmitter inductor is affected by an ability of the voltage regulator to achieve regulation for driving the load and a controller for controlling a peak current through the transmitter inductor, the controller being controlled to modulate the peak current through the transmitter inductor so as to modulate a peak current through the receiver inductor, wherein the peak voltage on the transmitter inductor increases during a time when the voltage regulator is able to achieve regulation, wherein the controller is configured to terminate modulating the peak current through the transmitter inductor, based on a change in the peak voltage, so that the voltage regulator is able to achieve regulation.