Wireless high power transfer under regulatory constraints

• US 8,466,654 B2
• Filed: 07/06/2009
• Issued: 06/18/2013
• Est. Priority Date: 07/08/2008
• Status: Active Grant

• Current Assignee: WiTricity Corporation
• Original Assignee: Qualcomm, Inc.
• Inventors: Cook, Nigel, Widmer, Hanspeter, Sieber, Lukas, Allred, David
• Primary Examiner(s): Tso, Edward
• Assistant Examiner(s): OMAR, AHMED H
• Application Number:
  US12/498,159
• Publication Number:
  US 20100117596A1
• Time in Patent Office: 1,443 Days
• Field of Search: 320/108, 320/109
• US Class Current: 320/109
• CPC Class Codes: B60L 2210/20 AC to AC converters
• CPC Class Codes: B60L 53/126 Methods for pairing a vehicle and a charging station, e.g. establishing a one-to-one relation between a wireless power transmitter and a wireless power receiver
• CPC Class Codes: B60L 53/38 specially adapted for charging by inductive energy transfer
• CPC Class Codes: B60L 53/60 Monitoring or controlling charging stations
• 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 1/2225 used in active tags, i.e. provided with its own power source or in passive tags, i.e. deriving power from RF signal
• 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: H04B 5/266 One coil at each side, e.g. with primary and secondary coils
• CPC Class Codes: H04B 5/79 for data transfer in combination with power transfer
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/7072 Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors
• CPC Class Codes: Y02T 10/72 Electric energy management in electromobility
• CPC Class Codes: Y02T 90/12 Electric charging stations
• CPC Class Codes: Y02T 90/14 Plug-in electric vehicles
• CPC Class Codes: Y02T 90/16 Information or communication technologies improving the operation of electric vehicles

Abstract

Improved battery-charging system for a vehicle. Primary and secondary coils are located in places where the vehicle can receive power from the primary coil by pulling into a parking space, for example. The parking space may have a coil embedded in the ground, or may have an array of coils embedded in the ground. A guidance system is disclosed. Fine positioning is also disclosed. The secondary coil in the vehicle can also be raised or lowered to improve coupling.

Claims

1. A transmitter system for wireless power, comprising:

a transmitting antenna including an inductive element and a capacitor, said transmitting antenna being resonant at a first frequency, said transmitting antenna being configured to generate a wireless field for charging a device including a receiving antenna;

a charging control system coupled to said transmitting antenna and configured to generate a signal at said first frequency and provide said signal to said transmitting antenna; and

an alignment controller configured to test coupling of said transmitting antenna to the receiving antenna in the first alignment position and based on a degree of the coupling, the alignment controller further configured to adjust an x-y alignment of the transmitting antenna relative to the receiving antenna from the first alignment position to a second alignment position having a finer alignment between the receiving antenna and the transmitting antenna than the first alignment position to improve said coupling.

2. The transmitter system of claim 1, wherein said first frequency is 135 kHz.

3. The transmitter system of claim 2, wherein said transmitting antenna is a coil having a radial width larger than its axial width.

4. The transmitter system of claim 1, wherein said transmitting antenna includes an array of antennas that extend over a specified area of a parking space.

5. The transmitter system of claim 4, wherein said charging control system is further configured to select one of said antennas of said array.

6. The transmitter system of claim 5, further comprising a switching device connected between the charging control system and each of the antennas of the array, the switching device configured to transmit the signal to the selected antenna of the array.

7. The transmitter system of claim 1, wherein said charging control system configured to generate a signal of a type that, when output to said transmitting antenna, transmits power to a remote receiving antenna.

17. The apparatus of claim 1, wherein the transmitting antenna is embedded in the ground.

18. The apparatus of claim 1, wherein the coupling test comprises a measurement of the amount of power that is transferred to the receiving antenna.

8. A receiver system for wireless power, comprising:

a receiving antenna coupled to a device, the receiving antenna including a coil and capacitor that are resonant at a first frequency;

a guidance controller configured to guide the receiving antenna of the device to a first alignment position relative to a transmitting antenna that is not physically connected to said device coupled to the receiving antenna;

a lifting device for said receiving antenna configured to lift and lower said receiving antenna; and

an alignment controller configured to sense a degree of coupling of said receiving antenna and the transmitting antenna based on a detection of the coupling that is measured at the receiving antenna, the alignment controller being further configured to move said receiving antenna from the first alignment position to a second alignment position to better align the receiving antenna with the transmitting antenna.

9. The receiver system of claim 8, further comprising an x-y alignment control configured to automatically align said receiving antenna to better align the receiving antenna with the transmitting antenna by moving said receiving antenna in x and y directions based on a degree of coupling between the receiving antenna and the transmitting antenna.

10. The receiver system of claim 8, further comprising circuitry that receives a magnetically induced signal from said receiving antenna and produces power therefrom.

11. The receiver system of claim 10, wherein said circuitry is resonant at 135 kHz.

12. The receiver system of claim 8, wherein said receiving antenna and said lifting device are part of a battery operated vehicle.

19. The apparatus of claim 8, wherein the sensed degree of coupling comprises a measurement of the amount of power that is transferred to the receiving antenna.

13. A method, comprising:

guiding a receiving antenna of a vehicle to a first alignment position relative to a transmitting antenna;

responsive to detecting a degree of coupling in the first alignment position between the receiving antenna and the transmitting antenna that is measured at the receiving antenna, moving one of the receiving antenna and the transmitting antenna from the first alignment position to a second alignment position to improve alignment of the receiving antenna with the transmitting antenna and improve the degree of coupling.

14. The method of claim 13, wherein moving one of the receiving antenna and the transmitting antenna comprises moving the receiving antenna laterally relative to the transmitting antenna.

15. The method of claim 13, wherein moving one of the receiving antenna and the transmitting antenna comprises moving the transmitting antenna laterally relative to the receiving antenna.

16. The method of claim 13, wherein moving one of the receiving antenna and the transmitting antenna comprises moving the receiving antenna along an axis that is perpendicular to one of a transmitting antenna coil and a receiving antenna coil.