Wireless energy transfer in lossy environments
Described herein are improved configurations for a wireless power transfer for electronic devices that include at least one source magnetic resonator including a capacitively-loaded conducting loop coupled to a power source and configured to generate an oscillating magnetic field and at least one device magnetic resonator, distal from said source resonators, comprising a capacitively-loaded conducting loop configured to convert said oscillating magnetic fields into electrical energy, wherein at least one said resonator has a keep-out zone around the resonator that surrounds the resonator with a layer of non-lossy material.
1. A wireless power transfer system comprising:
a source magnetic resonator comprising a capacitively-loaded conducting loop coupled to a power source and configured to generate an oscillating magnetic field to transfer power wirelessly to a device magnetic resonator, the source magnetic resonator having an unperturbed source quality factor Qs; and
a layer of non-lossy material that surrounds the source magnetic resonator to form a keep-out zone,
wherein a perturbed quality factor Q perturbed of the source magnetic resonator due to lossy material outside the keep-out zone is at least 50% of the unperturbed source quality factor Qs.
2. The system of claim 1 , wherein the keep-out zone extends at a symmetric distance around the source magnetic resonator.
3. The system of claim 1 , wherein the keep-out zone extends at an asymmetric distance around the source magnetic resonator.
4. The system of claim 3 , wherein the keep-out zone is largest around regions of the source magnetic resonator where electric fields are largest.
5. The system of claim 1 , wherein the keep-out zone exceeds 0.25 mm.
6. The system of claim 1 , wherein the keep-out zone exceeds 1 cm.
7. The system of claim 1 , wherein the keep-out zone exceeds 10 cm.
8. The system of claim 1 , wherein the keep-out zone is approximately 1.0% greater than a characteristic size of the source magnetic resonator.
9. The system of claim 1 , wherein the keep-out zone is approximately 0.1% greater than a characteristic size of the source magnetic resonator.
10. The system of claim 1 , wherein the source magnetic resonator further comprises a magnetic material.
11. The system of claim 1 , wherein the unperturbed source quality factor Qs is greater than 100.
12. The system of claim 10 , wherein at least one magnetic resonator is immersed in water.
13. The system of claim 10 , wherein at least one magnetic resonator is immersed in oil.
14. The system of claim 10 , wherein the source magnetic resonator is immersed in earthen materials.
15. The system of claim 10 , wherein the source magnetic resonator is located in a well.
16. The system of claim 10 , wherein at least one magnetic resonator is located inside a living creature.
17. A method for wireless power transfer comprising:
energizing a source magnetic resonator comprising a capacitively-loaded conducting loop to generate an oscillating magnetic field to transfer power wirelessly to a device magnetic resonator, the source magnetic resonator having an unperturbed source quality factor Qs;
providing a layer of non-lossy material to form a keep-out zone around the source magnetic resonator to maintain a separation distance between the source magnetic resonator and lossy material of the environment; and
maintaining a perturbed quality factor Q perturbed of the source magnetic resonator due to lossy material outside the keep-out zone of at least 50% of the unperturbed source quality factor Qs.
18. The method of claim 17 , wherein the keep-out zone extends at a symmetric distance around the source magnetic resonator.
19. The method of claim 17 , wherein the keep-out zone extends at an asymmetric distance around the source magnetic resonator.
20. The method of claim 17 , wherein the keep out zone exceeds 0.25 mm.
21. The method of claim 17 , wherein the keep out zone exceeds 1 cm.
22. The method of claim 17 , wherein the keep out zone exceeds 10 cm.
23. The method of claim 17 , wherein the keep out zone is approximately 1.0% greater than a characteristic size of the source magnetic resonator.
24. The method of claim 17 , wherein the keep out zone is approximately 0.1% greater than a characteristic size of the source magnetic resonator.
25. The method of claim 17 , wherein the source magnetic resonator further comprises a magnetic material.
26. The method of claim 17 , wherein the unperturbed source quality factor Qs is greater than 100.
27. The method of claim 26 , wherein at least one magnetic resonator is immersed in water.
28. The method of claim 26 , wherein at least one magnetic resonator is immersed in oil.
29. The method of claim 26 , wherein the source magnetic resonator is immersed in earthen materials.
30. The method of claim 26 , wherein the source magnetic resonator is located in a well.
31. The method of claim 26 , wherein at least one magnetic resonator is located inside a living creature.