Method for detecting load in wireless charging priority

1. A method for detecting a device in wireless charging, the method comprising:

storing waveform information of a first power to be transmitted for detecting the device;

generating the first power for detecting the device;

sensing a second power being transmitted according to the generation of the first power; and

detecting a device based at least in part on comparison of a waveform of the sensed second power and the stored waveform information of the first power.

2. The method of claim 1 , wherein the waveform information is waveform information relating to a current of the first power to be transmitted.

3. The method of claim 1 , wherein the waveform information is waveform information relating to a voltage of the first power to be transmitted.

4. The method of claim 1 , wherein the waveform information is waveform information relating to an open state without any load.

5. The method of claim 1 , wherein detecting the device comprises detecting a ramp-up of the sensed second power within a predetermined time interval.

6. The method of claim 5 , wherein the ramp-up occurs within a predetermined time interval that corresponds to a transmission time of the second power transmitted according to the first power.

7. The method of claim 5 , wherein the ramp-up occurs by charging a capacitive element of a wireless power receiver.

8. The method of claim 5 , wherein if the ramp-up is detected within the predetermined time interval, it is determined that at least one wireless power receiver is located within a charging area.

9. The method of claim 1 , further comprising determining a type of the device based on the comparison.

10. The method of claim 1 , further comprising determining whether the device is proximate to a charging area based on the comparison.

11. A wireless power transmitter for detecting a device in wireless charging, the wireless power transmitter comprising:

a memory to store waveform information of a first power to be transmitted for detecting the device;

a controller configured to:

generate the first power for detecting the device;

sense a second power being transmitted according to the generation of the first power; and

detect a device based at least in part on comparison of a waveform of the sensed second power and the stored waveform information of the first power.

12. The wireless power transmitter of claim 11 , wherein the waveform information is waveform information relating to a current of the first power to be transmitted.

13. The wireless power transmitter of claim 11 , wherein the waveform information is waveform information relating to a voltage of the first power to be transmitted.

14. The wireless power transmitter of claim 11 , wherein the waveform information is waveform information relating to an open state without any load.

15. The wireless power transmitter of claim 11 , wherein the controller is further configured to detect a ramp-up of the sensed second power within a predetermined time interval the device by charging a capacitive element of a wireless power receiver.

16. The wireless power transmitter of claim 11 , wherein the controller is further configured to determine a type of the device based on the comparison.

17. The wireless power transmitter of claim 16 , wherein the controller is further configured to determine the type of the device based on a category of a wireless power receiver.

18. The wireless power transmitter of claim 11 , wherein the controller is further configured to determine whether a device is located proximate to a charging area based on the comparison.

19. The wireless power transmitter of claim 18 , wherein it is determined whether the device is proximate to the charging area based on whether the waveform of the sensed second power falls or rises relative to a waveform in an open state.

20. The wireless power transmitter of claim 11 , wherein the first power to be transmitted is a short beacon power.