Tunable wireless energy transfer systems

• US 10,218,224 B2
• Filed: 04/21/2016
• Issued: 02/26/2019
• Est. Priority Date: 09/27/2008
• Status: Active Grant

• Current Assignee: WiTricity Corporation
• Original Assignee: WiTricity Corporation
• Inventors: Campanella, Andrew J., Lou, Herbert T., Kesler, Morris P., Hall, Katherine L., Fiorello, Ron, Karalis, Aristeidis
• Primary Examiner(s): Williams, Arun C
• Application Number:
  US15/134,827
• Publication Number:
  US 20160233726A1
• Time in Patent Office: 1,041 Days
• Field of Search: 320108
• CPC Class Codes: B60L 2200/26 Rail vehicles
• CPC Class Codes: H01F 38/14 Inductive couplings for wireless supply or distribution of electric power using inductive coupling H02J50/10
• CPC Class Codes: H01Q 7/00 Loop antennas with a substantially uniform current distribution around the loop and having a directional radiation pattern in a plane perpendicular to the plane of the loop
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H03H 7/40 Automatic matching of load impedance to source impedance

Abstract

This application includes systems and techniques relating to wireless power transfer, such as a system including: sensing and measurement circuitry configured to process signals associated with a resonator and an impedance matching network coupled with the resonator; a PWM (pulse width modulation) generator configured to control a driving signal to drive the resonator through the impedance matching network; and a controller coupled with the sensing and measurement circuitry, the controller configured to adjust operation of the PWM generator and operation of the impedance matching network based on measured signals from the sensing and measurement circuitry.

Claims

1. A system for wireless power transfer comprising:

sensing and measurement circuitry configured to process signals associated with a resonator and an impedance matching network coupled with the resonator;

a PWM (pulse width modulation) generator configured to control a driving signal to drive the resonator through the impedance matching network, the PWM generator being coupled with at least two power transistors of an amplifier coupled with the impedance matching network to drive the resonator through the impedance matching network; and

a controller coupled with the sensing and measurement circuitry, the controller configured to adjust operation of the PWM generator and operation of the impedance matching network based on measured signals from the sensing and measurement circuitry, including the controller being configured to control a duty cycle of the driving signal, a phase of the driving signal, or both the duty cycle and the phase of the driving signal from the PWM generator to adjust a power output level, an impedance, or both the power output level and the impedance, while maintaining a zero voltage switching condition at the amplifier.

2. The system of claim 1, wherein the system is an integrated circuit chip.

3. The system of claim 1, wherein at least one of the resonator or the impedance matching network includes a tunable component.

4. The system of claim 3, wherein the controller is configured to control a component value or operating point of the tunable component.

5. The system of claim 4, wherein the controller is configured to adjust operation and characteristics of the resonator, including power delivered to and by the resonator.

6. The system of claim 3, wherein the controller is configured to adjust a resonant frequency of the resonator.

7. The system of claim 1, wherein the sensing and measurement circuitry includes signal filtering and buffering circuits.

8. The system of claim 1, wherein the sensing and measurement circuitry includes differential or single-ended conversion circuitry.

9. The system of claim 1, wherein the sensing and measurement circuitry is coupled to an analog-to-digital converter (ADC).

10. The system of claim 1, wherein the controller is configured to control the duty cycle of the driving signal from the PWM generator to adjust the power output level, the impedance, or both the power output level and the impedance, while maintaining the zero voltage switching condition at the amplifier.

11. The system of claim 10, wherein the amplifier is a class-D or class-E switching amplifier.

12. The system of claim 10, wherein the controller is configured to control a voltage output of an adjustable DC supply coupled to the amplifier.

13. The system of claim 12, wherein the controller is coupled to a Vbus controller, the Vbus controller configured to control the voltage output of the adjustable DC supply to control power output by the amplifier and power delivered by the resonator.

14. The system of claim 10, wherein the controller is configured to control the phase and a frequency of the driving signal from the PWM generator to adjust the power output level, the impedance, or both the power output level and the impedance, while maintaining the zero voltage switching condition at the amplifier.

15. The system of claim 14, wherein controller is configured to maintain a zero current switching condition at the amplifier, in addition to the zero voltage switching condition at the amplifier, when controlling the duty cycle, the phase, and the frequency of the driving signal from the PWM generator to adjust both the power output level and the impedance.

16. The system of claim 15, further comprising fault detection circuitry configured to change or interrupt operation of the amplifier.

17. The system of claim 16, wherein the fault detection circuitry comprises one or more comparators to monitor voltage or current signals of the system.

18. The system of claim 17, wherein the comparators monitor bus voltage.

19. The system of claim 16, wherein the fault detection circuitry has an output to cause a change to the PWM generator, a system shutdown, or reduction of output power.

20. The system of claim 1, further comprising communication circuitry coupled to the controller.

21. The system of claim 1, wherein the controller is configured to control the phase of the driving signal from the PWM generator to adjust the power output level, the impedance, or both the power output level and the impedance, while maintaining the zero voltage switching condition at the amplifier.

22. The system of claim 21, wherein controller is configured to maintain a zero current switching condition at the amplifier, in addition to the zero voltage switching condition at the amplifier, when controlling the phase of the driving signal from the PWM generator to adjust both the power output level and the impedance.

23. The system of claim 22, wherein the controller is configured to control a voltage output of an adjustable DC supply coupled to the amplifier to control power output by the amplifier and power delivered by the resonator.

24. The system of claim 10, wherein controller is configured to maintain a zero current switching condition at the amplifier, in addition to the zero voltage switching condition at the amplifier, when controlling the duty cycle of the driving signal from the PWM generator to adjust both the power output level and the impedance.

25. The system of claim 24, wherein the controller is configured to control a voltage output of an adjustable DC supply coupled to the amplifier to control power output by the amplifier and power delivered by the resonator.

26. The system of claim 10, wherein the controller is configured to control the duty cycle and the phase of the driving signal from the PWM generator to adjust the power output level, the impedance, or both the power output level and the impedance, while maintaining the zero voltage switching condition at the amplifier.

27. The system of claim 26, wherein controller is configured to maintain a zero current switching condition at the amplifier, in addition to the zero voltage switching condition at the amplifier, when controlling the duty cycle and the phase of the driving signal from the PWM generator to adjust both the power output level and the impedance.

28. The system of claim 27, wherein the controller is configured to control a voltage output of an adjustable DC supply coupled to the amplifier to control power output by the amplifier and power delivered by the resonator.

29. The system of claim 28, wherein the controller is configured to control the duty cycle, the phase and a frequency of the driving signal from the PWM generator to adjust both the power output level and the impedance, while maintaining the zero voltage switching condition and the zero current switching condition at the amplifier.