Transmitters for wireless power transmission

• US 8,532,724 B2
• Filed: 09/16/2009
• Issued: 09/10/2013
• Est. Priority Date: 09/17/2008
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Cook, Nigel P., Sieber, Lukas, Widmer, Hanspeter
• Primary Examiner(s): Nguyen, Simon
• Application Number:
  US12/561,069
• Publication Number:
  US 20100184371A1
• Time in Patent Office: 1,455 Days
• Field of Search: 455/107, 455121-123, 455/126, 455/127.5, 455/129, 455/82, 455/575.7
• US Class Current: 455/575.7
• CPC Class Codes: H02J 50/10 using inductive coupling
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02J 50/23 characterised by the type of transmitting antennas, e.g. directional array antennas or Yagi antennas
• CPC Class Codes: H03F 3/2176 Class E amplifiers

Abstract

Exemplary embodiments are directed to wireless power transfer. A wireless power transmitter includes a transmit antenna configured as a resonant tank including a loop inductor and an antenna capacitance. The transmitter further includes an amplifier configured to drive the transmit antenna and a matching circuit operably coupled between the transmit antenna and the amplifier. The transmitter also includes a capacitor integrating the antenna capacitance and a matching circuit capacitance.

Claims

1. A wireless power transmitter, comprising:

a transmit antenna configured as a resonant tank, the transmit antenna including a first capacitor coupled in parallel with a first inductor;

a second inductor coupled in series with the transmit antenna;

a second capacitor coupled in series with the second inductor and the transmit antenna; and

a driver configured to drive the transmit antenna, the driver coupled in series with the second capacitor.

2. The transmitter of claim 1, wherein the driver is configured as a class-E driver.

3. The transmitter of claim 2, wherein the class-E driver is configured as an asymmetric class-E driver.

4. The transmitter of claim 2, wherein the class-E driver is configured as a symmetric class-E driver.

5. The transmitter of claim 1, wherein the second inductor and the first capacitor together filter a signal and match an impedance of a load.

6. The transmitter of claim 1, further comprising an intermediate driver configured to drive the driver.

7. The transmitter of claim 6, wherein the intermediate driver is configured as one of a resonant-type intermediate driver or a push-pull intermediate driver.

8. The transmitter of claim 1, wherein the transmit antenna comprises a pad antenna.

9. A wireless power transmitter, comprising:

a transmit antenna configured as a resonant tank, the transmit antenna including a first capacitor coupled in parallel with a first inductor; and

a driver configured as a dual half bridge driver to drive the transmit antenna, the driver comprising a second inductor and a third inductor.

10. The transmitter of claim 9, further comprising an intermediate driver configured to drive the driver.

11. The transmitter of claim 10, wherein the intermediate driver is configured as one of a resonant-type intermediate driver or a push-pull intermediate driver.

12. The transmitter of claim 9, wherein the transmit antenna comprises a pad antenna.

13. A method for transmitting wireless power, comprising:

driving a transmit antenna by a driver, the transmit antenna configured as a resonant tank including a first capacitor coupled in parallel with a first inductor, a second inductor coupled in series with the transmit antenna, a second capacitor coupled in series with the second inductor and the transmit antenna, and the driver coupled in series with the second capacitor; and

resonating the transmit antenna according to a capacitance of the first capacitor.

14. The method of claim 13, wherein the driving the transmit antenna further comprises driving the transmit antenna according to an inductance of the second inductor, and wherein the second inductor and the first capacitor together are configured to filter a signal and match an impedance of a load.

15. The method of claim 13, wherein the driver is configured as a class-E driver.

16. The method of claim 15, wherein the class-E driver is configured as a push-pull class-E driver.

17. The method of claim 13, further comprising one of driving the driver with a resonant-type intermediate driver or driving the driver with a push-pull intermediate driver.

18. A wireless power transmitter, comprising:

means for transmitting power wirelessly to a receiver, the means for transmitting power comprising;

first means for storing energy in an electric field; and

first means for storing energy in a magnetic field coupled in parallel with the first means for storing energy in an electric field;

second means for storing energy in an electric field coupled in series with the means for transmitting power;

second means for storing energy in an electric field coupled in series with the second means for storing energy in a magnetic field and the means for transmitting power; and

means for driving the means for transmitting power, the means for driving coupled in series with the second means for storing energy in an electric field.

19. The transmitter of claim 18, wherein the second means for storing energy in a magnetic field and the first means for storing energy in an electric field together provide means for filtering a signal and matching an impedance of a load.

20. The transmitter of claim 18, wherein the means for driving the means for transmitting power comprises a driver.

21. The transmitter of claim 20, wherein the driver is configured as a class-E driver.