Wireless power receiver for adjusting magnitude of wireless power

• US 10,069,340 B2
• Filed: 10/19/2012
• Issued: 09/04/2018
• Est. Priority Date: 10/19/2011
• Status: Active Grant

• Current Assignee: Korea Advanced Institute of Science and Technology, Samsung Electronics Co. Ltd.
• Original Assignee: Korea Advanced Institute of Science and Technology, Samsung Electronics Co. Ltd.
• Inventors: Yeo, Sung-Ku, Cho, Gyu-Hyeong, Kim, Se-Ki, Kim, Yu-Su, Park, Se-Ho, Choi, Jun-Han
• Primary Examiner(s): Barnie, Rexford
• Assistant Examiner(s): Mourad, Rasem
• Application Number:
  US13/656,142
• Publication Number:
  US 20130099588A1
• Time in Patent Office: 2,146 Days
• CPC Class Codes: H02J 50/10 using inductive coupling
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02J 50/80 involving the exchange of data, concerning supply or distribution of electric power, between transmitting devices and receiving devices
• CPC Class Codes: H02M 7/2176 comprising a passive stage to generate a rectified sinusoidal voltage and a controlled switching element in series between such stage and the output

Abstract

A wireless power receiver for wirelessly receiving power from a wireless power supplier includes a power receiver for receiving wireless power from the wireless power supplier and storing the wireless power for a first time period, a rectifier connected to the power receiver for rectifying the wireless power, a power adjuster connected to the rectifier and an output end, for adjusting a magnitude of the wireless power by enabling the power receiver to store the wireless power for the first time period and delivering the wireless power to the output end for a second time period, and a controller for determining the first and second time periods.

Claims

1. A wireless power receiver that wirelessly receives power from a wireless power supplier, the wireless power receiver comprising:

a power receiver configured to receive the power wirelessly from the wireless power supplier, wherein the power receiver comprises a coil, a first capacitor connected to the coil in series and a second capacitor connected to the coil in parallel;

a rectifier, connected to the power receiver, configured to rectify the received power;

a switch configured to connect the rectifier to an output end; and

a controller configured to;

control the switch to disconnect the rectifier from the output end for a duration of a first time period such that the received power circulates in a closed loop composed of the coil, the first capacitor and the second capacitor,

control the switch to connect the rectifier to the output end for delivering the rectified power to the output end without converting the rectifier power for a duration of a second time period, periodically,

determine whether to increase or to decrease a magnitude of power to be delivered from the rectifier to the output end from a first non-zero value to a second non-zero value, and

adjust the duration of the first time period and the duration of the second time period based on the determination result,

wherein the magnitude of the power to be delivered from the rectifier to the output end is adjusted by changing a ratio of the duration of the first time period to the duration of the second time period.

2. The wireless power receiver of claim 1, wherein the switch is configured to be open-circuited to disconnect the rectifier from the output end during the duration of the first time period and to be short-circuited to connect the rectifier to the output end during the duration of the second time period.

3. The wireless power receiver of claim 1, wherein the switch comprises an N-type metal-oxide-semiconductor field-effect transistor (MOSFET) device,

wherein the controller is further configured to determine the duration of the first time period and the duration of the second time period by adjusting a voltage applied to a gate of the N-type MOSFET.

4. The wireless power receiver of claim 3, further comprising a bootstrapper that bootstraps the voltage applied to the gate of the N-type MOSFET.

5. The wireless power receiver of claim 4, wherein the bootstrapper comprises a resonance inductor, connected to the gate of the N-type MOSFET device, configured to reduce a loss of the bootstrapping, and first and second switches configured to be alternately open-circuited and short-circuited in response to high and low signals.

6. The wireless power receiver of claim 1, wherein the switch comprises a P-type metal-oxide-semiconductor field-effect transistor (MOSFET) device.

7. The wireless power receiver of claim 1, further comprising a feedback circuit configured to send the rectified power to the controller as feedback power,

wherein the controller is further configured to determine the duration of the first time period and the duration of the second time period based on the feedback power.

8. The wireless power receiver of claim 7, wherein the controller is further configured to compare a voltage of the feedback power to a reference voltage, determine the duration of the first time period and the duration of the second time period based on the comparison result, and generate a power adjustment signal to control an operation of the switch.

9. The wireless power receiver of claim 8, further comprising a sync detector that detects, from the received power, a sync signal to be in phase with the power adjustment signal,

wherein the controller is further configured to generate the power adjustment signal based on the sync signal.

10. The wireless power receiver of claim 7, further comprising a communication unit configured to communicate with the wireless power supplier,

wherein the controller is further configured to generate a wireless power control signal to control the power transmitted from the wireless power supplier based on the feedback power, and control the communication unit to transmit the wireless power control signal to the wireless power supplier.

11. The wireless power receiver of claim 10, wherein the wireless power control signal includes at least one of identification information of the wireless power receiver, information regarding wireless reception, position information, environment setting information, safety-related information, and control information for the wireless power supplier.

12. The wireless power receiver of claim 11, wherein the control signal for the wireless power supplier includes at least one of control information for an application voltage of the wireless power supplier, control information of frequency and duty cycle of a power supply signal.

13. The wireless power receiver of claim 1, further comprising a regulator configured to generate output power by filtering out ripples of the rectified power.

14. The wireless power receiver of claim 1, wherein the rectifier comprises full-bridge diodes.

15. A method of controlling a wireless power receiver for wirelessly receiving power from a wireless power supplier, wherein the power receiver comprises a coil, a first capacitor connected to the coil in series and a second capacitor connected to the coil in parallel, the method comprising:

receiving the power wirelessly from the wireless power supplier;

rectifying the received power;

preventing the rectified power from being output by disconnecting a path to the output end for a duration of a first time period such that the received power circulates in a closed loop composed of the coil, the first capacitor and the second capacitor, and delivering the rectified power to the output end without converting the rectified power for a duration of a second time period, periodically,

determining whether to increase or to decrease a magnitude of power to be delivered from the rectifier to the output end from a first non-zero value to a second non-zero value, and

adjusting the duration of the first time period and the duration of the second time period based on the determination result,

wherein the magnitude of the power to be delivered from the rectifier to the output end is adjusted by changing a ratio of the duration of the first time period to the duration of the second time period.

16. The method of claim 15, further comprising sending the rectified power back as feedback power and analyzing the feedback power,

wherein the duration of the first time period and the duration of second time period are determined based on the feedback power.

17. The method of claim 16, wherein the first and second time periods are determined based on a comparison between a voltage of the feedback power and a reference voltage,

further comprising generating and outputting a power adjustment signal to control the wireless power receiver for each of the first and second time periods.

18. The method of claim 17, further comprising detecting from the received power a sync signal to be in phase with the power adjustment signal,

wherein the generating and outputting of the power adjustment signal comprises generating the power adjustment signal based on the sync signal.

19. The method of claim 16, wherein generating and outputting the power adjustment signal comprises:

generating a wireless power control signal to control the power transmitted from the wireless power supplier based on the feedback power; and

transmitting the wireless power control signal to the wireless power supplier.

20. The method of claim 19, wherein the wireless power control signal includes at least one of identification information of the wireless power receiver, information regarding wireless reception, position information, environment setting information, safety-related information, and control information for the wireless power supplier.

21. The method of claim 20, wherein the control signal for the wireless power supplier includes at least one of control information for an application voltage of the wireless power supplier, control information of frequency and duty cycle of a power supply signal.

22. The method of claim 15, further comprising generating an output power by filtering out ripples of the rectified power.