Apparatus and method for detecting foreign objects in wireless power transmission system

Patent metadata

Field	Value
Publication number	US-12413103-B2
Application number	US-202318463917-A
Country	US
Kind code	B2
Filing date	Sep 8, 2023
Priority date	Jul 10, 2012
Publication date	Sep 9, 2025
Grant date	Sep 9, 2025

Abstract

Aspects of the present invention relate to an apparatus and method for detecting foreign objects in a wireless power transmission system. This specification provides a wireless power reception apparatus for detecting foreign objects, including a power measurement unit for generating required power information indicative of required power for the wireless power reception apparatus, sending the required power information to a wireless power transmission apparatus, and measuring power induced from the wireless power transmission apparatus and a secondary coil for receiving the power induced from the wireless power transmission apparatus. In accordance with the present invention, foreign objects intervened between the wireless power transmission apparatus and the wireless power reception apparatus are recognized, and a user removes the foreign objects. Accordingly, damage to a device attributable to foreign objects can be prevented.

First claim

What is claimed is:

1. A wireless power reception apparatus, comprising:
a secondary coil configured to receive wireless power from a wireless power transmission apparatus; and
a controller configured to:
communicate, to the wireless power transmission apparatus, control information indicating a requested power,
measure a plurality of measured power values indicative of received power that the wireless power reception apparatus receives from the wireless power transmission apparatus in response to the control information, and
detect a foreign object during reception of the wireless power when a plurality of consecutive measured power values indicate a threshold difference between received power and the requested power.

2. The wireless power reception apparatus of claim 1 , wherein the controller is further configured to inform the wireless power transmission apparatus to stop or suspend transmission of the wireless power based on the detection of the foreign object.

3. The wireless power reception apparatus of claim 1 , wherein the controller is further configured to communicate an indication to the wireless power transmission apparatus based on the detection of the foreign object.

4. The wireless power reception apparatus of claim 1 , wherein the controller is further configured to:
generate a plurality of reception power measurement results, wherein each reception power measurement result indicates a difference between a corresponding measured power value and the requested power,
wherein the controller configured to detect the foreign object includes the controller being configured to detect the foreign object when at least two consecutive reception power measurement results indicate differences that exceed a threshold amount.

5. The wireless power reception apparatus of claim 1 , wherein the controller is configured to:
generate a plurality of reception power measurement results, wherein each reception power measurement result indicates whether a corresponding power measurement value is greater than, equal to, or smaller than the requested power; and
wherein the controller configured to detect the foreign object includes the controller being configured to detect the foreign object when at least two consecutive reception power measurement results indicate at least two corresponding power measurement values are both greater than or both smaller than the requested power.

6. The wireless power reception apparatus of claim 1 , wherein the controller is further configured to communicate a foreign object detection (FOD) declaration in response to detecting the foreign object.

7. The wireless power reception apparatus of claim 1 , wherein the controller is configured to:
wherein the controller configured to detect the foreign object includes the controller being configured to detect the foreign object based on an analysis of the plurality of consecutive measured power values measured during reception of the wireless power after communicating the control information indicating the requested power.

8. A method of a wireless power reception apparatus, comprising:
communicating, to a wireless power transmission apparatus, control information indicating a requested power of the wireless power reception apparatus;
receiving wireless power from the wireless power transmission apparatus;
measuring a plurality of measured power values indicative of received power that the wireless power reception apparatus receives from the wireless power transmission apparatus in response to the control information; and
detecting a foreign object during reception of the wireless power when a plurality of consecutive measured power values indicate a threshold difference between received power and the requested power.

9. The method of claim 8 , further comprising informing the wireless power transmission apparatus to stop or suspend transmission of the wireless power based on the detecting the foreign object.

10. The method of claim 8 , further comprising communicating an indication to the wireless power transmission apparatus based on the detecting the foreign object.

11. The method of claim 8 , further comprising:
generating a plurality of reception power measurement results, wherein each reception power measurement result indicates a difference between a corresponding measured power value and the requested power; and
wherein the detecting the foreign object includes detecting the foreign object when at least two consecutive reception power measurement results indicate differences that exceed a threshold amount.

12. The method of claim 8 , further comprising:
generating a plurality of reception power measurement results, wherein each reception power measurement result indicates whether a corresponding power measurement value is greater than, equal to, or smaller than the requested power; and
wherein the detecting the foreign object includes detecting the foreign object when at least two consecutive reception power measurement results indicate at least two corresponding power measurement values are both greater than or both smaller than the requested power.

13. The method of claim 8 , further comprising communicating a foreign object detection (FOD) declaration in response to the detecting the foreign object.

14. The method of claim 8 ,
wherein the detecting the foreign object includes detecting the foreign object based on an analysis of the plurality of consecutive measured power values measured during reception of the wireless power after communicating the control information indicating the requested power.

15. The method of claim 8 , further comprising:
wherein the detecting the foreign object includes detecting, by the wireless power reception apparatus, that the foreign object has been placed in a magnetic field during reception of the wireless power when the plurality of consecutive measured power values have a difference between received power and the requested power that exceeds a threshold amount.

16. A method of a wireless power transmission apparatus, comprising:
receiving, from a wireless power reception apparatus, first control information indicating a requested power of the wireless power reception apparatus;
transmitting wireless power to the wireless power reception apparatus via a primary coil;
periodically receiving second control information indicative of received power measured at the wireless power reception apparatus; and
determining that a foreign object is present during transmission of the wireless power when a plurality of consecutively received second control information indicate a threshold difference between the received power and the requested power.

17. The method of claim 16 , further comprising:
entering a power suspending mode when the foreign object is determined to be present, wherein the power suspending mode includes decreasing or stopping a driver of the primary coil.

18. The method of claim 16 , further comprising:
magnetically coupling the primary coil of the wireless power transmission apparatus to a secondary coil of the wireless power reception apparatus; and
controlling a driver of the primary coil to generate wireless power based on the first control information and the second control information.

19. The method of claim 16 , wherein the second control information includes at least one of:
a measured power value indicating a measured received power;
a difference between the requested power and the measured received power; or
an indication whether the measured received power is gre

Assignees

• Ge Hybrid Tech Llc

Inventors

• Jung Chun-Kil
• Hong Sug Ky

Classifications

• H02J7/42

  with electronic devices having internal batteries, e.g. mobile phones · CPC title

• H02J50/10 Primary

  using inductive coupling · CPC title

• H02J50/80

  involving the exchange of data, concerning supply or distribution of electric power, between transmitting devices and receiving devices · CPC title

• H02J50/12

  of the resonant type · CPC title

• H04B5/79

  for data transfer in combination with power transfer · CPC title