System and method for communication in wireless power supply systems

• US 10,250,083 B2
• Filed: 03/14/2013
• Issued: 04/02/2019
• Est. Priority Date: 05/20/2012
• Status: Active Grant

• Current Assignee: Philips IP Ventures B.V. (Koninklijke Philips N.V.)
• Original Assignee: Philips IP Ventures B.V. (Koninklijke Philips N.V.)
• Inventors: Taylor, Joshua B., Norconk, Matthew J., Moore, Colin J., Moes, Benjamin C., Veiseh, Merdad, Liff, Dale R., Blaha, Mark A., Amistadi, Jason L.
• Primary Examiner(s): Barnie, Rexford
• Assistant Examiner(s): Ortiz, Elim
• Application Number:
  US14/400,731
• Publication Number:
  US 20150194814A1
• Time in Patent Office: 2,210 Days
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02J 50/402 the two or more transmitting or the two or more receiving devices being integrated in the same unit, e.g. power mats with several coils or antennas with several sub-antennas
• 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: H04B 5/263 Multiple coils at either side
• CPC Class Codes: H04B 5/72 for local intradevice communication
• CPC Class Codes: H04B 5/79 for data transfer in combination with power transfer

Abstract

The present invention relates to wireless power supplies adapted to supply power and communicate with one or more remote devices. The systems and methods of the present invention generally relate to a communication timing system that may ensure information being communicated does not overlap with that of another device, preventing data collisions and information from going undetected. With information being communicated in a way that addresses or avoids potential communication issues in multiple device systems, the wireless power supply may control operation to effectively supply wireless power.

Claims

1. A wireless power supply for transferring power to at least one remote device, said wireless power supply comprising:

a wireless power transmitter for transferring power to the at least one remote device, said wireless power transmitter configured to form an inductive power link between said wireless power supply and the at least one remote device;

a communication circuit coupled to said wireless power transmitter, said communication circuit configured to transmit and receive information from the at least one remote device via said inductive power link, wherein said information transmitted to the at least one remote device provides first timing information to the at least one remote device indicative of one or more time slots available to the at least one remote device for communication with said communication circuit;

wherein in response to receiving communication, via said inductive power link, from the at least one remote device in at least one of said one or more time slots, said communication circuit is configured to assign the at least one time slot as occupied by the at least one remote device; and

wherein said information transmitted to the at least one remote device subsequent to said assignment includes second timing information indicative of the at least one time slot being occupied and indicative of one or more time slots as available for communication with said communication circuit;

wherein based on assignment of the at least one time slot as occupied by the at least one remote device, the communication circuit is configured to identify further communications received via said inductive power link in said at least one time slot as being transmitted from the at least one remote device.

2. The wireless power supply of claim 1 wherein said wireless power supply is configured to transfer power to a plurality of remote devices, and wherein said communication circuit is configured to assign each of the remote devices to one of said time slots.

3. The wireless power supply of claim 1 wherein said information includes a plurality of bit fields each indicating a state of one of said time slots, and wherein said state identifies whether each of said time slots is assigned or open.

4. The wireless power supply of claim 3 wherein said communication circuit is configured to change a state of one of said time slots in response to receiving communication from the at least one remote device in said one of said time slots.

5. The wireless power supply of claim 3 wherein said information includes a sync pulse that alerts the at least one remote device to expect said plurality of bit fields.

6. The wireless power supply of claim 1 wherein said communication circuit is configured to adjust a first characteristic of power in response to messages received in time slots assigned to the at least one remote device.

7. The wireless power supply of claim 6 wherein said communication circuit is configured to modulate information over said inductive power link by varying a second characteristic of power.

8. The wireless power supply of claim 7 wherein said first and second characteristic of power include at least one of operating frequency, resonant frequency, rail voltage, duty cycle, and phase, and wherein said second characteristic of power is different from said first characteristic of power.

24. The wireless power supply of claim 1 said communication circuit is configured to ignore partial communication in the time slots, wherein in response to receiving communication, via said inductive power link, from a different remote device in an unoccupied time slot, said communication circuit is configured to assign the unoccupied time slot as occupied by the different remote device.

9. A method of operating a wireless power supply to transfer power to at least one remote device, said method comprising:

placing the remote device in sufficient proximity to a wireless power supply to form an inductive power link between the wireless power supply and the remote device;

operating the wireless power supply to transfer power to the remote device via the inductive power link;

transmitting, from the wireless power supply, a first communication packet to the remote device via the inductive power link, the communication packet having timing information indicative of one or more time slots available to the remote device for communication with the wireless power supply;

receiving, in the wireless power supply, a message from the remote device in at least one time slot of the one or more time slots;

assigning, at least one time slot as occupied by the remote device based on receipt of the message from the remote device via the inductive power link;

transmitting, from the wireless power supply, via the inductive power link a second communication packet subsequent to the assignment, the second communication packet having timing information indicative of the at least one time slot being occupied and indicative of one or more time slots as available for communication with said communication circuit; and

identifying further messages received via the inductive power link in the at least one time slot assigned as occupied by the remote device as being transmitted from the remote device.

10. The method of claim 9 wherein said receiving includes receiving the message from the remote device in one of the time slots, and further comprising associating the remote device with the one of the time slots.

11. The method of claim 10 further comprising:

associating a state with each of the time slots, the state indicating whether each of the time slots is assigned or open;

in response to associating the remote device with one of the time slots, changing the state of one of the time slots from open to assigned; and

re-transmitting the communication packet, the communication packet including information about the state of each of the time slots.

12. The method of claim 10 further comprising receiving, in the wireless power supply, a second message from another remote device in another of the time slots;

and associating the another remote device with the another of the time slots.

13. The method of claim 9 further comprising adjusting a characteristic of power transferred to the remote device based on the message received from the remote device.

14. The method of claim 13 wherein the characteristic of power includes at least one of operating frequency, resonant frequency, rail voltage, duty cycle, and phase.

15. The method of claim 9 further comprising configuring for single power control mode in response to the message from the remote device being a non-standard packet of information.

16. The method of claim 9 further comprising periodically supplying power and shutting off in response to determining the at least one remote device is absent from a coupling region of the wireless power supply.

17. A remote device for receiving power from a wireless power supply, said remote device being separable from the wireless power supply, said remote device comprising:

a wireless power receiver for generating electrical power in response to a field generated by the wireless power supply;

communication circuitry for communicating with the wireless power supply;

a load coupled to said wireless power receiver, said load for receiving electrical power generated in said wireless power receiver in response to said field; and

wherein said communication circuitry is configured to receive information indicative of one or more time slots in which the wireless power supply is configured to receive communication from said remote device, wherein said communication circuitry is configured to select one of said one or more time slots for communication in via the field generated by the wireless power supply, and wherein said communication circuitry is configured to transmit a message in said selected time slot via the field, wherein said communication circuitry is configured to receive information subsequent to said selection relating to said selected time slot being occupied and one or more time slots in which the wireless power supply is configured to receive communication, wherein in response to said information relating to said selected time slot being occupied, said communication circuitry is configured to transmit further messages in said selected time slot via the field, and wherein the wireless power supply associates said further messages received in said selected time slot via the field as being transmitted from said remote device.

18. The remote device of claim 17 wherein said communication circuitry is configured to select said selected time slot based on an indication in said received information that said selected time slot is available for communication.

19. The remote device of claim 18 wherein said communication circuitry is configured to wait for the wireless power supply to indicate a start of said selected time slot before transmitting said message.

20. The remote device of claim 17 wherein said message includes information relating to a request to adjust an amount of power being transmitted by the wireless power supply via the field.

21. The remote device of claim 17 wherein said communication circuitry is configured to select a different time slot in response to information received from the wireless power supply indicating that a state of said selected time slot remains unchanged from an open state.

22. The remote device of claim 21 further comprising regulation circuitry configured to regulate power being received by at least one of reducing power being received, reconfiguring an impedance of said wireless power receiver, reconfiguring rectification circuitry, and varying a Q of said remote device.

23. The remote device of claim 17 wherein said communication circuitry is configured to control whether said remote device is in a multi-device power control mode or a single-device power control mode.

25. The remote device of claim 17 wherein said further messages transmitted in said occupied time slot via the field include a request for the wireless power supply to adjust power transmission to the remote device, and wherein in response to a lack of power adjustment in the remote device, the communication circuitry is configured to transmit a message in an unoccupied time slot.