APPARATUSES AND RELATED METHODS FOR MODULATING POWER OF A WIRELESS POWER RECEIVER

• US 20140265610A1
• Filed: 03/13/2013
• Published: 09/18/2014
• Est. Priority Date: 03/13/2013
• Status: Active Grant

• Current Assignee: Integrated Device Technology Incorporated (Renesas Electronics Corporation)
• Original Assignee: Integrated Device Technology Incorporated (Renesas Electronics Corporation)
• Inventors: Bakker, Anton, Lambert, Craig
• Granted Patent: US 9,998,180 B2
• Time in Patent Office: Days
• US Class Current: 307/104
• CPC Class Codes: G05B 13/0205 not using a model or a simulator of the controlled system
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02J 50/60 responsive to the presence of foreign objects, e.g. detection of living beings
• 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 7/219 in a bridge configuration
• CPC Class Codes: H04B 5/72 for local intradevice communication
• CPC Class Codes: H04B 5/79 for data transfer in combination with power transfer
• CPC Class Codes: Y02B 70/10 Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes

Abstract

A wireless power enabled apparatus may comprise a wireless power receiver that includes a receive coil configured to generate an AC signal responsive an electromagnetic field, a rectifier including a plurality of switches configured to receive the AC signal and generate an output power signal, and control logic configured to control the plurality of switches to cause the rectifier to modulate the output power signal. The control logic may be configured to control the plurality of switches within the rectifier to have an overlap delay that modulates at least one parameter of the wireless power receiver. A method of operating a receiver side of a wireless power transfer system comprises generating an output power signal including a rectified voltage and a rectified current responsive to receiving a wireless power signal, and controlling a rectifier according to at least one mode including a power modulation mode modulating the output power signal.

Claims

1. A wireless power enabled apparatus, comprising:

a wireless power receiver, including;

a receive coil configured to generate an AC power signal responsive to an electromagnetic field;

a rectifier including a plurality of switches configured to receive the AC power signal and generate a DC output power signal; and

control logic configured to control the plurality of switches to cause the rectifier to modulate the DC output power signal.

2. The wireless power enabled apparatus of claim 1, wherein the control logic is configured to control the plurality of switches to have an overlap delay such that the plurality of switches are temporarily enabled at the same time.

3. The wireless power enabled apparatus of claim 2, wherein the control logic is further configured to monitor a voltage of the wireless power receiver and adjust a duration for the overlap delay in response to monitoring the voltage.

4. The wireless power enabled apparatus of claim 3, wherein the voltage monitored is the rectified voltage.

5. The wireless power enabled apparatus of claim 3, wherein the control logic is configured to increase the overlap delay when the rectified voltage exceeds a threshold.

6. The wireless power enabled apparatus of claim 3, wherein the control logic is configured to increase the overlap delay based on an increasing trend in the rectified voltage.

7. The wireless power enabled apparatus of claim 2, wherein the control logic is configured to modulate a duration of the overlap delay for communicating data from the wireless power receiver to another device.

8. The wireless power enabled apparatus of claim 1, wherein the control logic is configured to control the plurality of switches to modulate the DC output power signal by temporarily shorting the receive coil during wireless power transfer.

9. The wireless power enabled apparatus of claim 1, further comprising an electronic device including the wireless power receiver.

10. The wireless power enabled apparatus of claim 7, further comprising a load operably coupled with the wireless power receiver to receive the DC output power signal.

11. The wireless power enabled apparatus of claim 7, wherein the load includes at least one of a battery of the electronic device and system components of the electronic device.

12. A wireless power enabled apparatus, comprising:

a wireless power receiver, including;

a receive coil;

a rectifier including a plurality of switches configured to receive a power signal generated from the receive coil and generate an output power signal in response thereto; and

control logic configured to control the plurality of switches within the rectifier to have an overlap delay that modulates at least one parameter of the wireless power receiver.

13. The wireless power enabled apparatus of claim 12, wherein the at least one parameter is selected from the group consisting of:

a voltage level of a rectified voltage of the output power signal;

a current value of a rectified current of the output power signal;

a voltage across the receive coil; and

a resonant capacitance that is detected by a wireless power transmitter.

14. The wireless power enabled apparatus of claim 12, wherein the control logic is further configured to modulate the overlap delay for communicating data to a wireless power transmitter.

15. The wireless power enabled apparatus of claim 12, wherein the rectifier includes a plurality of low-side switches operably coupled to a plurality of high-side diodes, wherein the overlap delay is a duration where the plurality of low-side switches are simultaneously enabled.

16. A method of operating a receiver side of a wireless power transfer system, the method comprising:

generating an output power signal including a rectified voltage and a rectified current responsive to receiving a wireless power signal; and

controlling a rectifier according to at least one mode including a power modulation mode modulating the output power signal.

17. The method of claim 16, wherein controlling a rectifier according to at least one mode further includes a normal mode wherein each of a plurality of switches within the rectifier are controlled as ideal diodes.

18. The method of claim 16, wherein controlling a rectifier according to at least one mode further includes a communication mode modulating a duration of an overlap delay of a plurality of switches within the rectifier to communicate data to another device at a different frequency as wireless power transfer.

19. The method of claim 16, wherein modulating the output power signal includes controlling a plurality of switches within the rectifier to have an overlap delay during which each switch is simultaneously enabled.

20. The method of claim 19, wherein controlling a plurality of switches within the rectifier to have an overlap delay includes delaying a turnoff transition of at least one of the plurality of switches.