WIRELESS INDUCTIVE POWER TRANSFER

• US 20150303995A1
• Filed: 11/26/2013
• Published: 10/22/2015
• Est. Priority Date: 11/29/2012
• Status: Active Grant

• Current Assignee: Koninklijke Philips N.V.
• Original Assignee: Koninklijke Philips N.V.
• Inventors: STARING, Antonius Adriaan Maria, VAN WAGENINGEN, Andries
• Granted Patent: US 10,771,112 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• 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: H02J 7/00 Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
• CPC Class Codes: H02J 7/00034 Charger exchanging data with an electronic device, i.e. telephone, whose internal battery is under charge
• CPC Class Codes: H04B 5/26 using coils
• 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

A power transmitter (101) is arranged to transfer power to a power receiver (105) using a wireless inductive power signal. The power transmitter (101) comprises a power signal generator (207) which drives an inductor (103) to provide the power signal to an inductor of the power receiver (105). A power loop control is employed by the power receiver (105) providing power control error messages to the power transmitter (101). The power transmitter (101) comprises a query message processor (209) which can detect a query message received from the power receiver (105) using load modulation of the power signal. A modification processor (211) is arranged to modify a response of the power loop controller to the power control error messages dependent on the query message. The power receiver (105) can detect the modifications to the operation of the power control and thus can interpret this as a response to the query message.

Claims

1. A power transmitter for transferring power to a power receiver using a wireless inductive power signal, the power transmitter comprising:

an inductor for providing the power signal;

a power signal generator for driving the inductor to provide the power signal;

a receiver for receiving data messages from the power receiver, the data messages being communicated by load modulation of the power signal;

a power loop controller arranged to control a power of the power signal in response to power control error messages received from the power receiver;

a query message processor for detecting that a query message has been received from the power receiver; and

a modification processor for modifying during a power transfer phase a response of the power loop controller to power control error messages in response to the query message.

2. The power transmitter of claim 1 wherein the modification processor is arranged to ignore at least one error control message in response to the query message.

3. The power transmitter of claim 1 wherein the power control error messages indicate a request for a power change of the power signal, and the modification processor is arranged to modify a response for at least one power control error message by changing a power of the power signal in an opposite direction to that requested by the at least one power control error message.

4. The power transmitter of claim 1 wherein the first processor is arranged to modify the responses to the power control error messages in accordance with a first pattern of modifications to responses to power control error messages.

5. The power transmitter of claim 4 wherein the first processor is arranged to select the first pattern from a plurality of patterns of modifications to responses to power control error messages in response to the query message, each pattern of the plurality of patterns corresponding to a different response to the query message.

6. The power transmitter of claim 4 wherein the first pattern comprises at least one modification corresponding to no change of power of the power signal and at least one modification corresponding to changing the power of the power signal in accordance with the request of the power control error message.

7. The power transmitter of claim 1 wherein the query message comprises an indication of a desired modification of the response of the power loop controller to power control error messages corresponding to a response to the query message.

8. The power transmitter of claim 1 wherein the modification processor is arranged to change the power of the power signal by changing an inductor current.

9. The power transmitter of claim 1 wherein the query message comprises a device identification, and the modification processor is arranged to modify the response dependent on the device identification.

10. The power transmitter of claim 1 wherein the query message comprises an indication of a technical specification with which the power receiver complies, and the modification processor is arranged to modify the response dependent on the indication of a technical specification.

11. The power transmitter of claim 1 wherein the query message is comprised in a configuration message transmitted prior to initialization of a power transfer phase.

12. The power transmitter of claim 1 wherein the modification is further dependent on a capability of the power transmitter.

15. A power transfer system comprising a power transmitter according to claim 1.

13. (canceled)

14. A power receiver for receiving power from a power transmitter using a wireless inductive power signal, the power receiver comprising:

an inductor for receiving the power signal;

a transmitter for transmitting data messages to the power transmitter, the data messages being communicated by load modulation of the power signal;

a query message processor for transmitting a query message to the power transmitter;

a power loop controller for transmitting power control error messages to the power transmitter, at least some of the power control error messages requesting a change in a power of the power signal;

a power signal monitor for monitoring power variations in the power signal; and

a response processor for determining, during a power transfer phase, a response to the query message in response to a comparison of the power variations in the power signal and power variations requested by the power control error messages.

18. A power transfer system comprising a power receiver according to claim 14.

16. A method of operation for a power transmitter arranged to transfer power to a power receiver using a wireless inductive power signal, the power transmitter comprising an inductor for providing the power signal and a power signal generator for driving the inductor to provide the power signal;

the method comprising;

receiving data messages from the power receiver, the data messages being communicated by load modulation of the power signal;

controlling a power of the power signal in response to power control error messages received from the power receiver (105);

detecting that a query message has been received from the power receiver; and

modifying, transfer phase, a response to power control error messages in response to the query message.

17. A method of operation for a power receiver arranged to receive power from a power transmitter using a wireless inductive power signal, the power receiver comprising an inductor for receiving the power signal;

the method comprising;

transmitting a query message to the power transmitter by load modulation of the power signal;

transmitting power control error messages to the power transmitter by load modulation of the power signal, at least some of the power control error messages requesting a change in a power of the power signal;

monitoring power variations in the power signal; and

determining, during a power transfer phase, a response to the query message in response to a comparison of the power variations in the power signal and power variations requested by the power control error messages.