Wireless power delivery over medium range distances using magnetic, and common and differential mode-electric, near-field coupling

• US 9,866,039 B2
• Filed: 11/13/2015
• Issued: 01/09/2018
• Est. Priority Date: 11/13/2015
• Status: Active Grant

• Current Assignee: Google LLC (Alphabet Inc.)
• Original Assignee: X Development LLC (Alphabet Inc.)
• Inventors: Adolf, Brian John, DeVaul, Richard Wayne
• Primary Examiner(s): LUU, AN T
• Application Number:
  US14/940,762
• Publication Number:
  US 20170141583A1
• Time in Patent Office: 788 Days
• CPC Class Codes: H02J 50/05 using capacitive coupling
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02J 50/502 the energy repeater being integrated together with the emitter or the receiver
• CPC Class Codes: H02J 50/60 responsive to the presence of foreign objects, e.g. detection of living beings
• CPC Class Codes: H02J 50/80 involving the exchange of data, concerning supply or distribution of electric power, between transmitting devices and receiving devices
• CPC Class Codes: H02J 7/00034 Charger exchanging data with an electronic device, i.e. telephone, whose internal battery is under charge
• CPC Class Codes: H04B 5/0012 using capacitive coupling
• CPC Class Codes: H04B 5/0037 for power transfer
• CPC Class Codes: H04B 5/0075 using inductive coupling transformers or inductances adapted for inductive coupling H01F38/14
• CPC Class Codes: H04B 5/22 Capacitive coupling
• CPC Class Codes: H04B 5/24 Inductive coupling
• CPC Class Codes: H04B 5/79 for data transfer in combination with power transfer

Abstract

Embodiments described herein may relate to a system comprising a power source configured to provide a signal at an oscillation frequency; a transmitter coupled to the power source, wherein the transmitter comprises at least one transmit resonator; one or more receivers, wherein the at least one receive resonator is operable to be coupled to the transmit resonator via a wireless resonant coupling link; one or more loads, wherein each of the one or more loads is switchably coupled to one or more respective receive resonators. The system includes a controller configured to determine an operational state of the system, wherein the operational state comprises at least one of three coupling modes (common mode, differential mode, and inductive mode), and is configured to cause the transmitter to provide electrical power to each of the one or more loads via the wireless resonant coupling link according to the determined operational state.

Claims

1. A system comprising:

a power source configured to provide a signal at an oscillation frequency;

a transmitter coupled to the power source, wherein the transmitter comprises at least one transmit resonator, wherein the at least one transmit resonator comprises at least one of;

a transmit inductor or at least one transmit capacitor, wherein the at least one transmit capacitor is at least a transmit common mode capacitor, wherein the transmit common mode capacitor comprises a transmitter conductor and a ground reference, wherein the at least one transmit resonator is configured to resonate at one or more transmitter resonance frequencies, wherein the one or more transmitter resonance frequencies comprise at least the oscillation frequency;

one or more receivers, wherein each receiver of the one or more receivers comprises at least one receive resonator, wherein the at least one receive resonator comprises at least one of;

a receive inductor or at least one receive capacitor, wherein the at least one receive capacitor is at least a receive common mode capacitor, wherein the receive common mode capacitor comprises a receiver conductor and the ground reference, wherein the at least one receive resonator is configured to resonate at one or more receiver resonance frequencies, wherein the one or more receiver resonance frequencies comprise at least one of the one or more transmitter resonance frequencies, and wherein the at least one receive resonator is operable to be coupled to the transmit resonator via a wireless resonant coupling link;

one or more loads, wherein each of the one or more loads is switchably coupled to one or more respective receive resonators; and

a controller configured to;

determine an operational state of the system, wherein the operational state comprises at least one of three coupling modes, wherein the three coupling modes are common mode, differential mode, and inductive mode,

cause the transmitter to provide electrical power to each of the one or more loads via the wireless resonant coupling link according to the determined operational state.

2. The system of claim 1, wherein the common mode comprises providing the wireless resonant coupling link via the at least one transmit common mode capacitor and the at least one receive common mode capacitor.

3. The system of claim 1, wherein the transmitter further comprises at least one transmit differential mode capacitor formed between two differential mode conductors, wherein the one or more receivers comprise at least one receive differential mode capacitor formed between two differential mode conductors, and wherein the differential mode comprises providing the wireless resonant coupling link via the at least one transmit differential mode capacitor and the at least one receive differential mode capacitor.

4. The system of claim 1, wherein the transmitter further comprises at least one transmit inductive mode inductor, wherein the one or more receivers comprise at least one receive inductive mode inductor, and wherein the inductive mode comprises providing the wireless resonant coupling link via the at least one transmit inductive mode inductor and the at least one receive inductive mode inductor.

5. The system of claim 1, wherein causing the transmitter to provide electrical power to each of the one or more loads comprises distributing the electrical power to each of the one or more loads according to a time division multiple access (TDMA) method.

6. The system of claim 1, wherein one or more of the transmit inductor and the transmit capacitor is a distributed element.

7. The system of claim 1, wherein the controller is further configured to:

determine an amount of electrical power that the transmitter will deliver to each of the one or more loads via the wireless coupling link according to the determined operational state; and

in response to determining the amount of electrical power that the transmitter will deliver to each of the one or more loads, adjust at least the electrical power that the transmitter delivers to each of the one or more loads via each of the coupling modes of the determined operational state.

8. The system of claim 1, wherein the system further comprises:

one or more bidirectional couplers, wherein each of the bidirectional couplers is coupled to the transmitter; and

one or more impedance matching networks, wherein each of the impedance matching networks is coupled to at least one of;

the transmitter or at least one of the one or more receivers.

9. The system of claim 8, wherein the controller is further configured to:

receive, via the one or more bidirectional couplers, information indicative of a reflected signal from each of the one or more loads;

determine an impedance of each of the one or more loads based on the received information;

in response to determining the impedance of each of the one or more loads, adjust at least one of the one or more impedance matching networks.

10. The system of claim 8, wherein the controller is further configured to:

periodically adjust at least one of the one or more impedance matching networks, wherein the periodic adjustments occur according to a predetermined time period.

11. The system of claim 8, wherein the controller is further configured to:

determine a priority of at least one load of the one or more loads;

based on the determined priority, determine an amount of electrical power that the transmitter will provide to the at least one load;

in response to determining the amount of electrical power that the transmitter will provide to the at least one load, adjust at least one of the one or more impedance matching networks.

12. The system of claim 8, wherein the controller is further configured to:

determine an amount of electrical power that the transmitter will deliver to each of the one or more loads;

in response to determining the amount of electrical power that the transmitter will deliver to each of the one or more loads, adjust at least one of the one or more impedance matching circuits such that the system delivers the determined amount of electrical power to each of the one or more loads.

13. The system of claim 12, wherein the controller is further configured to:

in response to determining the amount of electrical power that the transmitter will deliver to each of the one or more loads, adjust at least the electrical power that the transmitter delivers to each of the one or more loads via each of the coupling modes of the determined operational state.

14. The system of claim 8, wherein the transmitter and at least one of the one or more receivers communicate by modulating at least one of:

the signal provided by the power source or the reflected signal.

15. The system of claim 8, wherein the controller is further configured to:

determine an ideal amount of electrical power that the transmitter will provide to each of the one or more loads;

determine an actual amount of electrical power received at each of the one or more loads;

compare the ideal amount of electrical power to the actual amount of electrical power received at each of the one or more loads; and

based at least on the comparison, determine one or more parasitic loads in the system.

16. The system of claim 8, wherein causing the transmitter to provide electrical power to each of the one or more loads comprises distributing the electrical power to each of the one or more loads according to a frequency division multiplexing access (FDMA) method.

17. A method comprising:

determining an operational state of the system, wherein the operational state comprises at least one of three coupling modes, wherein the three coupling modes are common mode, differential mode, and inductive mode;

causing a source coupled to a transmitter to provide a signal at an oscillation frequency;

in response to the signal, causing a transmit resonator of the transmitter to resonate at the oscillation frequency, wherein the transmit resonator comprises at least one of;

a transmit inductor or at least one transmit capacitor, wherein the at least one transmit capacitor is at least a transmit common mode capacitor, wherein the transmit common mode capacitor comprises a transmitter conductor and a ground plane;

in response to the transmit resonator resonating at the oscillation frequency, causing at least one receive resonator of one or more receivers to resonate at the oscillation frequency, wherein each receive resonator comprises at least one of;

a receive inductor or at least one receive capacitor, wherein the at least one receive capacitor is at least a receive common mode capacitor, wherein the receive common mode capacitor comprises a receiver conductor and the ground plane, wherein each one of one or more loads is associated with one or more receivers, wherein each of the one or more loads is switchably coupled to the respective receive resonator of its associated receiver, and wherein each respective receive resonator is operable to be coupled to the transmit resonator via a wireless resonant coupling link;

causing the transmitter to transmit electrical power to each of the one or more loads via the wireless resonant coupling link according to the determined operational state.

18. The method of claim 17, wherein causing the transmitter to transmit electrical power to each of the one or more loads comprises distributing the electrical power to each of the one or more loads according to a time division multiple access (TDMA) method.

19. The method of claim 17, wherein the common mode comprises providing the wireless resonant coupling link via the at least one transmit common mode capacitor and the at least one receive common mode capacitor.

20. The method of claim 17, wherein the transmitter further comprises at least one transmit differential mode capacitor formed between two transmit differential mode conductors, wherein the one or more receivers comprise at least one receive differential mode capacitor formed between two receive differential mode conductors, and wherein the differential mode comprises providing the wireless resonant coupling link via the at least one transmit differential mode capacitor and the at least one receiver differential mode capacitor.

21. The method of claim 17, wherein the transmitter further comprises at least one transmit inductive mode inductor, wherein the one or more receivers comprise at least one receive inductive mode inductor, and wherein the inductive mode comprises providing the wireless resonant coupling link via the at least one transmit inductive mode inductor and the at least one receive inductive mode inductor.

22. The method of claim 17 further comprising:

determining an amount of electrical power that the transmitter will provide to each of the one or more loads via the wireless coupling link according to the determined operational state; and

in response to determining the amount of electrical power that the transmitter will provide to each of the one or more loads, adjusting at least the electrical power that the transmitter provides to each of the one or more loads via each of the coupling modes of the determined operational state.

23. The method of claim 17 further comprising:

receiving, via one or more bidirectional couplers, information indicative of a reflected signal from each of the one or more loads and information indicative of a power leaving the source, and wherein each bidirectional coupler is coupled to the transmitter;

determining an impedance of each of the one or more loads based on the received information.

24. The method of claim 17 further comprising:

determining an amount of electrical power that the transmitter will deliver to each of the one or more loads;

in response to determining the amount of electrical power that the transmitter will deliver to each of the one or more loads, adjusting at least one of the one or more impedance matching networks such that the system delivers the determined amount of electrical power to each of the one or more loads.

25. The method of claim 24, wherein each of the one or more impedance matching networks is associated with at least one of:

the transmitter or the one or more receivers.

26. The method of claim 24, further comprising:

periodically adjusting at least one of the one or more impedance matching networks, wherein the periodic adjustments occur according to a predetermined time period.

27. The method of claim 17, wherein the transmitter and each of the one or more receivers communicate by modulating one of:

the signal provided by the source or the reflected signal.

28. The method of claim 17, wherein one or more of the transmit inductor and the transmit capacitor is a distributed element.

29. The method of claim 17, wherein the oscillation frequency is at least one of one or more resonant frequencies of the transmit resonator.

30. The method of claim 17, wherein causing the transmitter to provide electrical power to each of the one or more loads comprises distributing the electrical power to each of the one or more loads according to a frequency division multiplexing access (FDMA) method.