Wireless power transfer using a field altering circuit

Patent metadata

Field	Value
Publication number	US-2016352147-A1
Application number	US-201615075344-A
Country	US
Kind code	A1
Filing date	Mar 21, 2016
Priority date	May 27, 2015
Publication date	Dec 1, 2016
Grant date	—

Abstract

A wireless power transmitter includes a power transmit coil configured to generate a magnetic field for wirelessly coupling charging power to one or more receiver devices, the magnetic field having a magnetic field distribution over an area defining a charging region, a circuit configured to alter the magnetic field generated by the power transmit coil to alter the magnetic field distribution, and a controller operably coupled to the circuit, the controller configured to control the circuit to alter the magnetic field distribution responsive to a detected characteristic of the one or more receiver devices.

First claim

What is claimed is:

1 . A wireless power transmitter, comprising:
a power transmit coil configured to generate a magnetic field for wirelessly coupling charging power to one or more receiver devices, the magnetic field having a magnetic field distribution over an area defining a charging region; a circuit configured to alter the magnetic field generated by the power transmit coil to alter the magnetic field distribution; and; a controller operably coupled to the circuit, the controller configured to control the circuit to alter the magnetic field distribution responsive to a detected characteristic of the one or more receiver devices.

2 . The wireless power transmitter of claim 1 , wherein the controller is configured to control the circuit to selectively amplify the magnetic field to alter the magnetic field distribution within at least a portion of the charging area responsive to the detected characteristic such that the magnetic field distribution is less uniform than the magnetic field distribution when the circuit is not activated.

3 . The wireless power transmitter of claim 2 , wherein the circuit is configured to operate as a resonant circuit.

4 . The wireless power transmitter of claim 1 , wherein the controller is configured to control the circuit to selectively attenuate the magnetic field to alter the magnetic field distribution within at least a portion of the charging area responsive to the detected characteristic such that the magnetic field distribution is more uniform than the magnetic field distribution when the circuit is not activated.

5 . The wireless power transmitter of claim 4 , wherein the circuit is configured to operate as a short circuit.

6 . The wireless power transmitter of claim 1 , wherein the magnetic field distribution is substantially constant over the charging region and wherein the controller is configured to control the circuit to one of selectively amplify the magnetic field and selectively attenuate the magnetic field to alter the magnetic field distribution responsive to the detected characteristic.

7 . The wireless power transmitter of claim 1 , wherein the power transmit coil comprises a plurality of coil segments and the circuit is located adjacent one of the plurality of coil segments of the power transmit coil.

8 . The wireless power transmitter of claim 1 , wherein the power transmit coil comprises a plurality of coil segments and the circuit is connected to one of the plurality of coil segments of the power transmit coil.

9 . The wireless power transmitter of claim 1 , wherein the power transmit coil comprises a plurality of antenna coil segments having a first antenna coil segment and a second antenna coil segment arranged at a periphery of the power transmit coil and a third antenna coil segment arranged at a center of the power transmit coil and the circuit is connected to the third antenna coil segment.

10 . The wireless power transmitter of claim 9 , wherein the circuit connected to the third antenna coil segment is configured to selectively amplify the magnetic field toward the center of the power transmit coil.

11 . The wireless power transmitter of claim 9 , wherein the circuit connected to the third antenna coil segment is configured to selectively attenuate the magnetic field toward the center of the power transmit coil.

12 . A device for generating a magnetic field having a magnetic field distribution over an area defining a charging region for wirelessly charging or powering one or more receiver devices, comprising:
means for detecting a characteristic of one or more receiver devices indicative of an amount or efficiency of wirelessly coupling charging power via the magnetic field generated by the device; and means for altering the magnetic field to alter the magnetic field distribution within the charging region in response to the detecting means.

13 . The device of claim 12 , wherein the means for altering the magnetic field further comprises means for selectively amplifying the magnetic field within at least a portion of the charging area such that the magnetic field distribution is less uniform than the magnetic field distribution when the means for altering the magnetic field is not activated.

14 . The device of claim 13 , further comprising means for operating a resonant circuit in a vicinity of the magnetic field.

15 . The device of claim 12 , wherein the means for altering the magnetic field further comprises means for selectively attenuating the magnetic field within at least a portion of the charging area such that the magnetic field distribution is more uniform than the magnetic field distribution when the means for altering the magnetic field is not activated.

16 . The device of claim 15 , further comprising means for operating a short circuit in a vicinity of the magnetic field.

17 . A method of operating a wireless power transmitter apparatus configured to generate a magnetic field having a magnetic field distribution over an area defining a charging region for wirelessly charging or powering one or more receiver devices, the method comprising:
detecting a characteristic of one or more receiver devices indicative of an amount or efficiency of wirelessly coupling charging power via the magnetic field generated by the wireless power transmitter apparatus; and altering the magnetic field to alter the magnetic field distribution within the charging region in response to detecting the characteristic.

18 . The method of claim 17 , wherein the method further comprises selectively amplifying the magnetic field within at least a portion of the charging area responsive to the characteristic of the one or more receiver devices such that the magnetic field distribution is less uniform than the magnetic field distribution when the magnetic field is not altered.

19 . The method of claim 18 , wherein altering the magnetic field further comprises operating a resonant circuit in a vicinity of the magnetic field.

20 . The method of claim 17 , wherein the method further comprises selectively attenuating the magnetic field within at least a portion of the charging area responsive to the characteristic of the one or more receiver devices such that the magnetic field distribution is more uniform than the magnetic field distribution when the magnetic field is not altered.

21 . The method of claim 20 , wherein altering the magnetic field further comprises operating a short circuit in a vicinity of the magnetic field.

22 . The method of claim 17 , wherein the method further comprises one of selectively amplifying the magnetic field and selectively attenuating the magnetic field within at least a portion of the charging area responsive to the characteristic of the one or more receiver devices such that the magnetic field distribution is different than the magnetic field distribution when the magnetic field is not altered.

23 . The method of claim 17 , wherein altering the magnetic field to alter the magnetic field distribution comprises altering the magnetic field corresponding to a first magnetic field distribution or altering the magnetic field corresponding to a second magnetic field distribution, different from the first magnetic field distribution.

24 . The method of claim 23 , wherein the first magnetic field distribution corresponds to a substantially uniform field distribution over the charging region.

25 . The method of c

Assignees

• Qualcomm Inc

Inventors

• Von Novak Iii William Henry
• Kallal Edward Kenneth
• Wheeland Cody Burton
• Jeong Seong Heon

Classifications

• H02J7/64

  against overvoltage · CPC title

• H02J7/61

  against overcharge · CPC title

• H02J7/60

  including safety or protection arrangements · CPC title

• B60L53/122

  Circuits or methods for driving the primary coil, e.g. supplying electric power to the coil · CPC title

• Y02T10/7072

  Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors · CPC title