US Patent 10919401 Integrated wireless power transfer system

A charging system includes an inverter configured to receive rectified mains line voltage and current to power a primary coil to induce charge current in a secondary coil of a vehicle. The charging system also includes a controller configured to alter a switching frequency of the inverter based on charge voltage data from the vehicle to cause the inverter to operate to drive a voltage of an energy storage capacitor of a battery charger of the vehicle toward a constant value.