Contactless power transfer system

• US 9,697,951 B2
• Filed: 08/28/2013
• Issued: 07/04/2017
• Est. Priority Date: 08/29/2012
• Status: Active Grant

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Bhat, Suma Memana Narayana, Raghunathan, Arun Kumar, Bohori, Adnan Kutubuddin
• Primary Examiner(s): BARNIE, REXFORD N
• Assistant Examiner(s): Inge, Joseph
• Application Number:
  US14/012,245
• Publication Number:
  US 20140062181A1
• Time in Patent Office: 1,406 Days
• Field of Search: 307 91, 307104
• CPC Class Codes: B60L 53/12 Inductive energy transfer
• CPC Class Codes: B60L 53/31 Charging columns specially adapted for electric vehicles
• CPC Class Codes: B60L 53/36 by positioning the vehicle
• CPC Class Codes: H01F 38/14 Inductive couplings for wireless supply or distribution of electric power using inductive coupling H02J50/10
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02J 50/402 the two or more transmitting or the two or more receiving devices being integrated in the same unit, e.g. power mats with several coils or antennas with several sub-antennas
• CPC Class Codes: H02J 50/90 involving detection or optimisation of position, e.g. alignment
• 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 90/12 Electric charging stations
• CPC Class Codes: Y02T 90/14 Plug-in electric vehicles

Abstract

A contactless power transfer system comprising a power exchanging coil configured to exchange power via a magnetic field, a field focusing element for focusing the magnetic field, and a compensation coil having a resonance frequency different from a resonance frequency of the field focusing element for matching an impedance of the contactless power transfer system and compensating a change in phase resulting from a misalignment in the contactless power transfer system.

Claims

1. A contactless power transfer system comprising:

a power exchanging coil configured to exchange power with a transmitter power coil via a magnetic field;

a field focusing element for receiving the magnetic field from the transmitter power coil and focusing the magnetic field onto the power exchanging coil, the field focusing element having a resonance frequency that is the same as a resonance frequency of the transmitter power coil; and

a compensation coil coupled to the power exchanging coil such that the power exchanging coil is positioned between the field focusing element and the compensation coil, the compensation coil having a compensation coil capacitor and a resonance frequency different from the resonance frequency of the field focusing element for matching an impedance of the contactless power transfer system and compensating a change in phase resulting from a misalignment of the power exchanging coil and the transmitter power coil.

2. The system of claim 1, wherein the field focusing element comprises at least one resonator.

3. The system of claim 2, wherein the at least one resonator comprises a plurality of resonators arranged in an array wherein the plurality of resonators operate together as a single unit and a resultant magnetic field is emitted by the plurality of resonators that is focused onto the power exchanging coil.

4. The system of claim 2, wherein the at least one resonator comprises at least two different resonance frequencies.

5. The system of claim 4, wherein the at least two different resonance frequencies enable transfer of power and data signals.

6. The system of claim 1, wherein the power exchanging coil is coupled between the field focusing element and the compensation coil.

7. The system of claim 1, wherein the contactless power transfer system is electrically coupled to a vehicle.

8. A system comprising:

a first power exchanging coil;

a contactless power transfer system coupled to the first power exchanging coil, wherein the contactless power transfer system exchanges power with the first power exchanging coil via a magnetic field, wherein the contactless power transfer system comprises;

a second power exchanging coil configured to exchange power with the first power exchanging coil via the magnetic field;

a field focusing element for receiving the magnetic field from the transmitter power coil and focusing the magnetic field onto the power exchanging coil, the field focusing element having a resonance frequency that is the same as a resonance frequency of the first power exchanging coil; and

a compensation coil coupled to the power exchanging coil such that the power exchanging coil is positioned between the field focusing element and the compensation coil, the compensation coil having a compensation coil capacitor and a resonance frequency different from the resonance frequency of the field focusing element for matching an impedance of the contactless power transfer system and compensating a change in phase resulting from a misalignment of the second power exchanging coil with respect to the first power exchanging coil.

9. The system of claim 8, wherein the first power exchanging coil comprises a transmitter coil and the contactless power transfer system comprises a receiver coil.

10. The system of claim 9, wherein the first power exchanging coil is electrically coupled to a power source and the contactless power transfer system is electrically coupled to a load.

11. The system of claim 10, wherein the load comprises an energy storage device.

12. The system of claim 8, wherein the field focusing element comprises at least one resonator.

13. The system of claim 12, wherein the at least one resonator comprises a plurality of resonators arranged in an array, wherein the plurality of resonators operate together as a single unit and a resultant magnetic field is emitted by the plurality of resonators that is focused onto the second power exchanging coil.

14. The system of claim 12, wherein the at least one resonator comprises at least two different resonance frequencies.

15. The system of claim 14, wherein the at least two different resonators frequencies enable transfer of power and data signals.

16. The system of claim 8, wherein the first power exchanging coil and the second power exchanging coil are configured to handle a bidirectional flow of power between the first power exchanging coil and the second power exchanging coil.

17. The system of claim 8, wherein the contactless power transfer system is electrically coupled to a vehicle.

18. A method comprising:

generating a magnetic field from power received from a first power exchanging coil;

receiving the magnetic field from the transmitter power coil using a field focusing element;

focusing the magnetic field onto a second power exchanging coil by the field focusing element, the field focusing element having a resonance frequency that is the same as a resonance frequency of the first power exchanging coil;

coupling a compensation coil to the power exchanging coil such that the power exchanging coil is positioned between the field focusing element and the compensation coil; and

compensating a change in phase and matching impedance using the compensation coil for enhancing power exchanging capability of the second power exchanging coil, wherein the compensation coil comprises a resonant frequency different from the resonance frequency of the field focusing element.