Apparatus for transmitting and receiving information about amount of power for identifying transmission efficiency associated with wireless power transfer and control method therefor

A wireless power receiver, comprising:

• a battery;
• a coil configured to receive alternating current (AC) power wirelessly transmitted by an external electronic device;
• a conversion circuitry configured to convert the AC power received via the coil into direct current (DC) power;
• a charging circuitry configured to charge the battery using the DC power;
• and
• a processor configured to:
• when detecting the external electronic device, set a power state including an amount of current and a voltage level associated with charging the battery to a specified state, using the charging circuitry,
• receive the AC power corresponding to the specified state from the external electronic device via the coil,
• convert the AC power into DC power using the conversion circuitry,
• while at least partially charging the battery using the DC power by the charging circuitry, receive information associated with an amount of transmit power transmitted from the external electronic device to the wireless power receiver,
• calculate reception efficiency based at least in part on the amount of transmit power and an amount of receive power received from the external electronic device;
• and
• adjust a power state of the charging circuitry to another specified state based at least in part on the reception efficiency.

A method of power control by a wireless power receiver, the method comprising:

• when detecting an external electronic device, setting a power state including an amount of current and a voltage level associated with charging a battery of the wireless power receiver to a specified state;
• receiving alternating current (AC) power corresponding to the specified state from the external electronic device via a coil of the wireless power receiver, converting the AC power into direct current (DC) power using a conversion circuitry of the wireless power receiver,
• while at least partially charging the battery using the DC power by a charging circuitry of the wireless power receiver, receiving information associated with an amount of transmit power transmitted from the external electronic device to the wireless power receiver,
• calculating reception efficiency based on the amount of transmit power and an amount of receive power received from the external electronic device;
• and
• adjusting a power state of the charging circuitry to another specified state based at least in part on the reception efficiency.