Apparatus and method for detecting foreign object in wireless power transmission system

An apparatus for receiving wireless power from a wireless power transmitter based on foreign object detection in a wireless power transmission system, the apparatus comprising:

• a power pick-up unit configured to receive wireless power from the wireless power transmitter through magnetic coupling with the wireless power transmitter and convert an alternating current (AC) signal generated by the wireless power to a direct current (DC) signal;
• a communication/control unit configured to receive the DC signal from the power pick-up unit and control the wireless power;
• and
• a load configured to receive the DC signal from the power pick-up unit,
• wherein the communication/control unit transmits, to the wireless power transmitter, a first End Power Transfer (EPT) packet that temporarily ends transmission of the wireless power for detection of a foreign object and performs a foreign object detection procedure within a predetermined time window if transmission of the wireless power is temporarily ended.