Wireless power receiver and power control method thereof

1. A method of controlling power in a wireless power receiver to wirelessly receive power from a wireless power transmitter and transmit the power to a load, the method comprising:

receiving AC power from the wireless power transmitter that receives power from a power supply device;

rectifying the AC power to DC power; and

controlling DC power applied to the load by comparing the DC power with a threshold voltage,

wherein the controlling the DC power applied to the load includes measuring the rectified DC power and allowing the load to enter the charging mode by transferring the DC power to the load when the DC power is equal to or greater than a first threshold voltage, maintaining the load in the charging mode by transferring the DC power to the load when measured DC power periodically is equal to or greater than a second threshold voltage in a state that the load enters the charging mode, and blocking a supply of the DC power to the load by allowing the switch to be switched off when the measured DC power periodically is less than the second threshold voltage.

2. The method of claim 1 , wherein the controlling DC power applied to the load includes controlling the DC power applied to the load by allowing the switch to be switched on or off according to a comparison result of the DC power with the threshold voltage.

3. The method of claim 1 , wherein the allowing the load to enter the charging mode includes transferring the DC power to the load by allowing switch to be switched on.

4. The method of claim 1 , wherein the controlling DC power applied to the load further includes blocking a supply of the DC power to the load by allowing the switch to be switched off when the DC power is less than the first threshold voltage.

5. The method of claim 1 , wherein the first threshold voltage is greater than the second threshold voltage.

6. The method of claim 1 , wherein blocking a supply of the DC power to the load includes blocking a supply of the DC power to the load by allowing the switch to be switched off.

7. The method of claim 1 , wherein the first threshold voltage is a minimum voltage required for the load to enter the charging mode, and the second threshold voltage is a minimum voltage required for the load to maintain the charging mode.

8. A method of controlling power in a wireless power receiver to wirelessly receive power from a wireless power transmitter and transmit the power to a load, the method comprising:

transmitting, by a control unit, an open signal to a switch to block a supply of a DC power to the load;

measuring, by the control unit, a first voltage applied to the switch;

confirming, by the control unit, whether the first voltage is equal to or higher than a first threshold voltage;

transmitting, by the control unit, a short signal to the switch when the first voltage is equal to or higher than the first threshold voltage; and

allowing, by the control unit, the load to enter a charging mode.

9. The method of claim 8 , further includes standing by for a first time before the measuring, by the control unit, a first voltage applied to the switch.

10. The method of claim 9 , further includes transmitting, by the control unit, a open signal to the switch when the first voltage is less than the first threshold voltage.

11. The method of claim 8 , further includes measuring a second voltage applied to the switch when the load enters into the charging mode.

12. The method of claim 11 , further includes confirming, by the control unit, whether the second voltage is equal to or higher than a second threshold voltage; and standing by for a second time when the second voltage is equal to or higher than the second threshold voltage.

13. The method of claim 12 , further includes measuring a third voltage applied to the switch when the second time is elapsed.

14. The method of claim 12 , further includes transmitting, by the control unit, an open signal to the switch when the second voltage is less than the second threshold voltage.

15. The method of claim 12 , wherein the first threshold voltage is greater than the second threshold voltage.

16. The method of claim 15 , wherein the first threshold voltage is a minimum voltage required for the load to enter the charging mode, and the second threshold voltage is a minimum voltage required for the load to maintain the charging mode.