Transmitters for wireless power transmission

• US 9,425,653 B2
• Filed: 09/06/2013
• Issued: 08/23/2016
• 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): AMAYA, CARLOS DAVID
• Application Number:
  US14/019,930
• Publication Number:
  US 20140001882A1
• Time in Patent Office: 1,082 Days
• Field of Search: 307/104
• US Class Current: 1/1
• 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 circuit configured as a resonant tank comprising a first capacitor coupled with a first inductor, the transmit circuit configured to wirelessly transmit power in response to a time-varying signal; and

a driver circuit operably coupled to the transmit circuit, the driver circuit configured to generate the time-varying signal, the driver circuit comprising;

a second inductor coupled in series with the transmit circuit; and

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

wherein the second inductor and the first capacitor define a filter configured to provide load matching and/or filtering of a signal generated by the driver or the transmit circuit.

2. The wireless power transmitter of claim 1, further comprising an intermediate driver circuit operably connected to the driver circuit and configured to drive the driver circuit.

3. The wireless power transmitter of claim 2, wherein the intermediate driver circuit is configured as one of a resonant-type intermediate driver circuit or a push-pull intermediate driver circuit.

4. The wireless power transmitter of claim 1, wherein the driver circuit is configured as a class-E driver circuit.

5. The wireless power transmitter of claim 4, wherein the class-E driver circuit is configured as a single-ended class-E driver circuit.

6. The wireless power transmitter of claim 4, wherein the class-E driver circuit is configured as a push-pull class-E driver circuit.

7. A method for transmitting wireless power, comprising:

transmitting power wirelessly, by a transmit circuit, in response to a time-varying signal, the transmit circuit configured as a resonant tank comprising a first capacitor coupled with a first inductor;

generating, by a driver circuit, the time-varying signal, the driver circuit comprising a second inductor coupled in series with the transmit circuit, and a second capacitor coupled in series with the second inductor and the transmit circuit; and

matching and/or filtering the time-varying signal by a filter comprising the second inductor and the first capacitor.

8. The method of claim 7, further comprising an intermediate driver circuit operably connected to the driver circuit and configured to drive the driver circuit.

9. The method of claim 8, wherein the intermediate driver circuit is configured as one of a resonant-type intermediate driver circuit or a push-pull intermediate driver circuit with the transmit circuit.

10. The method of claim 7, wherein the driver circuit is configured as a class-E driver circuit.

11. The method of claim 10, wherein the class-E driver circuit is configured as a single-ended class-E driver circuit.

12. The method of claim 7, wherein the class-E driver circuit is configured as a push-pull class-E driver circuit.

13. A driver circuit for use in wireless power transmitter, comprising:

means for transmitting power wirelessly in response to a time-varying signal, the means for transmitting comprising means for storing energy in a first electric field coupled with means for storing energy in a first magnetic field; and

means for generating the time-varying signal, the means for generating comprising means for storing energy in a second electric field coupled in series with the means for transmitting power, and means for storing energy in a second magnetic field coupled in series with the means for transmitting power and the means for storing energy in a second electric field;

wherein the means for storing energy in a second magnetic field and the means for storing energy in a first electric field define a means for filtering which provides load matching and/or filtering of the time-varying signal.

14. The wireless power transmitter of claim 13, further comprising an intermediate driver circuit operably connected to the means for generating and configured to drive the means for generating.

15. The wireless power transmitter of claim 14, wherein the intermediate driver circuit is configured as one of a resonant-type intermediate driver circuit or a push-pull intermediate driver circuit.

16. The wireless power transmitter of claim 13, wherein the means for generating is configured as a class-E driver circuit.

17. The wireless power transmitter of claim 16, wherein the class-E driver circuit is configured as a single-ended class-E driver circuit.

18. The wireless power transmitter of claim 13, wherein the class-E driver circuit is configured as a push-pull class-E driver circuit.

19. A wireless power transmitter, comprising:

a transmit circuit configured as a resonant tank comprising a first capacitor coupled with a first inductor, the transmit circuit configured to wirelessly transmit power in response to a time-varying signal to power or charge a receiver device; and

a driver circuit operably coupled to the transmit circuit, the driver circuit configured to generate the time-varying signal, the driver circuit comprising;

a first driver stage circuit comprising;

a first switch configured to control the time-varying signal in response to a first control signal;

a second capacitor coupled in parallel with the first switch;

a third capacitor coupled to the first switch and to the second capacitor; and

a second inductor coupled to the first switch and to the second capacitor; and

a second driver stage circuit comprising;

a second switch configured to control the time-varying signal in response to a second control signal;

a fourth capacitor coupled in parallel with the second switch;

a fifth capacitor coupled to the second switch and to the fourth capacitor; and

a third inductor coupled to the second switch and to the fourth capacitor.

20. The wireless power transmitter of claim 19, wherein the transmit circuit is coupled in parallel with the driver circuit.

21. The wireless power transmitter of claim 19, wherein the first driver stage circuit is configured as a class-E amplifier circuit, and wherein the second driver stage circuit is configured as a class-E amplifier circuit.