A wireless power transmitting apparatus for detecting a foreign object, the apparatus comprising: a primary core block adapted for being coupled with a secondary core block equipped in a wireless power receiving apparatus through magnetic induction or magnetic resonance and configured to transmit wireless power to the wireless power receiving apparatus (150-n) by the magnetic induction or the magnetic resonance; an electric driving unit operably connected to the primary core block and configured to apply an alternating current, AC, signal required for the primary core block to transmit the wireless power; and a control unit operably connected to the electric driving unit and configured to generate a control signal for controlling the AC signal, wherein the control unit is arranged to apply a control signal to the electric driving unit wherein the control unit is configured to perform a digital ping that includes transmission of a power signal at an initial operating point for a ping phase; wherein the control unit is configured to check whether a signal strength packet is received in a time window from the wireless power receiving apparatus; wherein when the signal strength packet is received in the time window, the control unit is arranged to check whether an identification packet and configuration information are received from the wireless power receiving apparatus, wherein the configuration information comprises a reference power value; wherein when the identification packet and the configuration information are received, the control unit is arranged to check whether a foreign object status packet is received from the wireless power receiving apparatus; wherein the control unit is configured to perform foreign object detection if the foreign object status packet is received from the wireless power receiving apparatus by: obtaining the reference power value from the wireless power receiving apparatus (150-n), wherein the reference power value represents an experimentally measured amount of power expected to be transmitted by a primary coil when no foreign object is present and the power signal is in a steady state of the initial operating point; and measuring an initial transmission power transmitted from the primary core block and to perform foreign object detection based on a comparison of the initial transmission power and the reference power value, after receiving from the wireless power receiving apparatus the foreign object status packet indicating start of the foreign object detection. a primary core block adapted for being coupled with a secondary core block equipped in a wireless power receiving apparatus through magnetic induction or magnetic resonance and configured to transmit wireless power to the wireless power receiving apparatus (150-n) by the magnetic induction or the magnetic resonance; an electric driving unit operably connected to the primary core block and configured to apply an alternating current, AC, signal required for the primary core block to transmit the wireless power; and a control unit operably connected to the electric driving unit and configured to generate a control signal for controlling the AC signal, wherein the control unit is arranged to apply a control signal to the electric driving unit wherein the control unit is configured to perform a digital ping that includes transmission of a power signal at an initial operating point for a ping phase; wherein the control unit is configured to check whether a signal strength packet is received in a time window from the wireless power receiving apparatus; wherein when the signal strength packet is received in the time window, the control unit is arranged to check whether an identification packet and configuration information are received from the wireless power receiving apparatus, wherein the configuration information comprises a reference power value; wherein when the identification packet and the configuration information are received, the control unit is arranged to check whether a foreign object status packet is received from the wireless power receiving apparatus; wherein the control unit is configured to perform foreign object detection if the foreign object status packet is received from the wireless power receiving apparatus by: obtaining the reference power value from the wireless power receiving apparatus (150-n), wherein the reference power value represents an experimentally measured amount of power expected to be transmitted by a primary coil when no foreign object is present and the power signal is in a steady state of the initial operating point; and measuring an initial transmission power transmitted from the primary core block and to perform foreign object detection based on a comparison of the initial transmission power and the reference power value, after receiving from the wireless power receiving apparatus the foreign object status packet indicating start of the foreign object detection. obtaining the reference power value from the wireless power receiving apparatus (150-n), wherein the reference power value represents an experimentally measured amount of power expected to be transmitted by a primary coil when no foreign object is present and the power signal is in a steady state of the initial operating point; and measuring an initial transmission power transmitted from the primary core block and to perform foreign object detection based on a comparison of the initial transmission power and the reference power value, after receiving from the wireless power receiving apparatus the foreign object status packet indicating start of the foreign object detection.