System and method for multi-coil dual backbone dynamic inductive power transfer

1. An apparatus for wirelessly transferring power to a receive coupler, the apparatus comprising:

a first coupler connected to a second coupler;

a third coupler overlapping the first coupler and the second coupler; and

a controller configured to:

receive power from at least one power supply,

provide a first current to the first coupler and the second coupler in a first charging mode, wherein a magnetic flux generated by the first current passing through a first portion of the first coupler is constructively additive with a magnetic flux generated by the first current passing through a second portion of the second coupler,

provide the first current to the first coupler and the second coupler and provide a second current to the third coupler in a second charging mode, and

reverse a polarity of the second current provided to the third coupler in the second charging mode based on a location of the receive coupler.

2. The apparatus of claim 1 , wherein the third coupler is symmetrically positioned over each of the first coupler and the second coupler.

3. The apparatus of claim 1 , wherein the controller is further configured to provide the second current having a first polarity in the second charging mode when the receive coupler is located over the second coupler and the third coupler.

4. The apparatus of claim 1 , wherein the controller is further configured to provide the second current having a second polarity in the second charging mode when the receive coupler is located over the first coupler and the third coupler.

5. The apparatus of claim 1 , wherein the controller is further configured to alternately reverse a polarity of the first current provided to the first and second couplers in the second charging mode based on a location of the receive coupler.

6. The apparatus of claim 5 , wherein the controller is further configured to determine the location based on a level of power transferred by the first and second couplers or a level of power transferred by the third coupler.

7. The apparatus of claim 1 , wherein the at least one power supply comprises a first power backbone and a second power backbone, the controller further configured to:

receive at least a first portion of the power from the first power backbone for providing the first current to the first coupler and the second coupler, and

receive at least a second portion of the power from the second power backbone for providing the second current to the third coupler.

8. The apparatus of claim 1 , wherein the controller is further configured to provide the first current 90° out of phase with respect to the second current.

9. A method for wirelessly transferring power to a receive coupler, the method comprising:

receiving power from at least one power supply,

providing a first current to a first coupler and to a second coupler connected to the first coupler in a first charging mode,

providing the first current to the first and second couplers and a second current to a third coupler that overlaps the first coupler and the second coupler in a second charging mode, and

reverse a polarity of the second current provided to the third coupler in the second charging mode based on a location of the receive coupler,

wherein a magnetic flux generated by the first current passing through a first portion of the first coupler is constructively additive with a magnetic flux generated by the first current passing through a second portion of the second coupler.

10. The method of claim 9 , wherein the third coupler is symmetrically positioned over each of the first coupler and the second coupler.

11. The method of claim 9 , further comprising providing the second current having a first polarity in the second charging mode when the receive coupler is located over the second coupler and the third coupler.

12. The method of claim 9 , further comprising providing the second current having the second polarity in the second charging mode when the receive coupler is located over the first coupler and the third coupler.

13. The method of claim 9 , further comprising alternately reversing a polarity of the first current provided to the first and second couplers in the second charging mode based on a location of the receive coupler.

14. The method of claim 13 , further comprising determining the location based on a level of power transferred by the first and second couplers or a level of power transferred by the third coupler.

15. The method of claim 9 , wherein receiving power from at least one power supply comprises:

receiving at least a first portion of the power from a first power backbone for providing the first current to the first coupler and the second coupler, and

receiving at least a second portion of the power from a second power backbone for providing the second current to the third coupler.

16. The method of claim 9 , wherein the first current is 90° out of phase with respect to the second current.

17. A non-transitory computer-readable medium comprising code that, when executed, causes an apparatus to:

receive power from at least one power supply,

provide a first current to a first coupler and to a second coupler connected to the first coupler in a first charging mode,

provide the first current to the first and second couplers and a second current to a third coupler that overlaps the first coupler and the second coupler in a second charging mode, and

reverse a polarity of the second current provided to the third coupler in the second charging mode based on a location of the receive coupler,

wherein a magnetic flux generated by the first current passing through a first portion of the first coupler is constructively additive with a magnetic flux generated by the first current passing through a second portion of the second coupler.

18. The medium of claim 17 , wherein the third coupler is symmetrically positioned over each of the first coupler and the second coupler.

19. The medium of claim 17 , wherein the code, when executed, further causes the apparatus to provide the second current having a first polarity in the second charging mode when the receive coupler is located over the second coupler and the third coupler.

20. The medium of claim 17 , wherein the code, when executed, further causes the apparatus to provide the second current having the second polarity in the second charging mode when the receive coupler is located over the first coupler and the third coupler.

21. The medium of claim 17 , wherein the code, when executed, further causes the apparatus to alternately reverse a polarity of the first current provided to the first and second couplers in the second charging mode based on a location of the receive coupler.

22. The medium of claim 21 , wherein the code, when executed, further causes the apparatus to determine the location based on a level of power transferred by the first and second couplers or a level of power transferred by the third coupler.

23. The medium of claim 17 , wherein receiving power from at least one power supply comprises:

receiving at least a first portion of the power from a first power backbone for providing the first current to the first coupler and the second coupler, and

receiving at least a second portion of the power from a second power backbone for providing the second current to the third coupler.

24. The medium of claim 17 , wherein the first current is 90° out of phase with respect to the second current.

25. An apparatus for wirelessly transferring power to a receive coupler, the apparatus comprising:

first means for wirelessly coupling power to a receive coupler;

second means for wirelessly coupling power to the receive coupler, the second means connected to the first means;

third means for wirelessly coupling power to the receive coupler, the third means overlapping the first means and the second means; and

means for providing a first current to the first means and the second means in a first charging mode, wherein a magnetic flux generated by the first current passing through a first portion of the first means is constructively additive with a magnetic flux generated by the first current passing through a second portion of the second means,

means for providing the first current to the first means and the second means and for providing a second current to the third means in a second charging mode, and

means for reversing a polarity of the second current provided to the third means in the second charging mode based on a location of the receive coupler.

26. The apparatus of claim 25 , wherein the third means is symmetrically positioned over each of the first means and the second means.

27. The apparatus of claim 25 , wherein the second current has a first polarity in the second charging mode when the receive coupler is located over the second means and the third means.

28. The apparatus of claim 25 , wherein the second current has the second polarity in the second charging mode when the receive coupler is located over the first means and the third means.

29. The apparatus of claim 25 , wherein the means for reversing is further configured to reverse a polarity of the first current provided to the first and second means in the second charging mode based on a location of the receive coupler.

30. The apparatus of claim 29 , further comprising means for determining the location based on a level of power transferred by the first and second means or a level of power transferred by the third means.