This application discloses wireless charging apparatuses, methods, and systems. One apparatus includes: a direct current to alternating current (DC-to-AC) inverter circuit configured to invert a DC output by a DC power supply to an AC; a compensation circuit configured to compensate the AC output by the DC-to-AC inverter circuit and send the AC obtained after the compensation to a transmitting coil; the transmitting coil configured to receive the AC and generate an AC magnetic field; an impedance adjustment circuit comprising one or more inductive branches; and a controller configured to control on or off of the switch in the inductive branch to change a current flowing out of the lagging bridge arm to enable a controllable switching transistor of the lagging bridge arm to implement zero-voltage switching.