WIRELESS ENERGY TRANSFER WITH VARIABLE SIZE RESONATORS FOR MEDICAL APPLICATIONS

• US 20120235634A1
• Filed: 10/21/2011
• Published: 09/20/2012
• Est. Priority Date: 09/27/2008
• Status: Active Grant

• Current Assignee: WiTricity Corporation
• Original Assignee: WiTricity Corporation
• Inventors: Hall, Katherine L., Efe, Volkan, Kesler, Morris P., Campanella, Andrew J., Karalis, Aristeidis, Kurs, Andre B., Soljacic, Marin, Kulikowski, Konrad
• Granted Patent: US 8,907,531 B2
• Time in Patent Office: Days
• US Class Current: 320/108
• CPC Class Codes: H01F 27/34 Special means for preventing or reducing unwanted electric or magnetic effects, e.g. no-load losses, reactive currents, harmonics, oscillations, leakage fields
• 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 5/005 with inductive power transfer for charging H02J7/025
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02J 50/50 using additional energy repeaters between transmitting devices and receiving devices
• CPC Class Codes: H02J 50/60 responsive to the presence of foreign objects, e.g. detection of living beings
• CPC Class Codes: H02J 50/70 involving the reduction of electric, magnetic or electromagnetic leakage fields
• 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 50/90 involving detection or optimisation of position, e.g. alignment
• CPC Class Codes: H02J 7/0029 with safety or protection devices or circuits
• CPC Class Codes: H02J 7/0047 with monitoring or indicating devices or circuits
• CPC Class Codes: H03H 7/40 Automatic matching of load impedance to source impedance
• CPC Class Codes: Y10S 323/911 Medical electronics

Abstract

A medical device-powering wireless receiver for use with a first electromagnetic resonator coupled to a power supply. The wireless receiver includes a load configured to power an implantable medical device using electrical power, and a second electromagnetic resonator adapted to be housed within the medical device and configured to be coupled to the load, wherein the second electromagnetic resonator is configured to be wirelessly coupled to the first electromagnetic resonator to provide resonant, non-radiative wireless power to the second electromagnetic resonator from the first electromagnetic resonator, the area circumscribed by the inductive element of at least one of the electromagnetic resonators can be varied to improve performance.

Claims

1. A medical device-powering wireless receiver for use with a first electromagnetic resonator coupled to a power supply, first electromagnetic resonator having a mode with a resonant frequency ω

₁, an intrinsic loss rate Γ

₁, and a first Q-factor Q₁=ω

₁/2Γ

₁, the wireless receiver comprising;

a load configured to power an implantable medical device using electrical power; and

a second electromagnetic resonator adapted to be housed within the medical device and configured to be coupled to the load, the second electromagnetic resonator having a mode with a resonant frequency ω

₂, an intrinsic loss rate Γ

₂, and a second Q-factor Q₂=ω

₂/2Γ

₂;

wherein the second electromagnetic resonator is configured to be wirelessly coupled to the first electromagnetic resonator to provide resonant, non-radiative wireless power to the second electromagnetic resonator from the first electromagnetic resonator;

wherein the area circumscribed by the inductive element of at least one of the electromagnetic resonators can be varied to improve performance; and

wherein the square root of the product of the respective Q factors is greater than 100.

2. The wireless receiver of claim 1, wherein the medical device is implantable in a patient.

3. The wireless receiver of claim 1, wherein the first resonator is substantially larger than the second resonator to facilitate the second resonator being implantable in a patient.

4. The wireless receiver of claim 1, wherein a repeater electromagnetic resonator is provided to deliver power from the first electromagnetic resonator to the second electromagnetic resonator.

5. The wireless receiver of claim 1, wherein the repeater electromagnetic resonator is disposed under the skin of a patient.

6. The wireless receiver of claim 1, wherein the repeater electromagnetic resonator is disposed in a wearable pack.

7. A power source for wirelessly providing power to a wireless receiver of an electrically powered implantable medical device, the power source comprising:

a power supply, the power supply configured to supply power at a rate sufficient to charge the battery of a medical device; and

a first electromagnetic resonator coupled to the power supply and having a mode with a resonant frequency ω

₁, an intrinsic loss rate Γ

₁, and a first Q-factor Q₁=ω

₁/2Γ

₁, the first electromagnetic resonator housed in a housing configured to be disposed remotely from the medical device;

wherein the first electromagnetic resonator is configured to be wirelessly coupled to a second electromagnetic resonator within the medical device and coupled to a load associated with the medical device to provide non-radiative wireless power to the second electromagnetic resonator, the second electromagnetic resonator having a mode with a resonant frequency ω

₂, an intrinsic loss rate Γ

₂, and a second Q-factor Q₂=ω

₂/2Γ

₂;

wherein the area circumscribed by the inductive element of at least one of the electromagnetic resonators can be varied to improve performance; and

wherein the square root of the product of the respective Q factors is greater than 100.

8. The power source of claim 7, wherein the medical device is implantable in a patient.

9. The power source of claim 7, wherein the first resonator is substantially larger than the second resonator to facilitate the second resonator being implantable in a patient.

10. The power source of claim 7, wherein a repeater electromagnetic resonator is provided to deliver power from the first electromagnetic resonator to the second electromagnetic resonator.

11. The power source of claim 7, wherein the repeater electromagnetic resonator is disposed under the skin of a patient.

12. The power source of claim 7, wherein the repeater electromagnetic resonator is disposed in a wearable pack.

13. A medical device wireless power system, comprising:

a power supply, the power supply configured to supply power at a rate sufficient to charge the battery of an implantable medical device;

a first electromagnetic resonator coupled to the power supply and having a mode with a resonant frequency ω

₁, an intrinsic loss rate Γ

₁, and a first Q-factor Q₁=ω

₁/2Γ

₁, the first electromagnetic resonator housed in a housing configured to be disposed remotely from the medical device;

a load configured to power the medical device using electrical power; and

a second electromagnetic resonator adapted to be housed within the medical device and configured to be coupled to the load, the second electromagnetic resonator having a mode with a resonant frequency ω

₂, an intrinsic loss rate Γ

₂, and a second Q-factor Q₂=ω

₂/2Γ

₂;

wherein the first electromagnetic resonator is configured to be wirelessly coupled to a second electromagnetic resonator within the medical device to provide non-radiative wireless power to the second electromagnetic resonator;

wherein the area circumscribed by the inductive element of at least one of the electromagnetic resonators can be varied to improve performance; and

wherein the square root of the product of the respective Q factors is greater than 100.

14. The wireless power system of claim 13, wherein the medical device is implantable in a patient.

15. The wireless power system of claim 13, wherein the first resonator is substantially larger than the second resonator to facilitate the second resonator being implantable in a patient.

16. The wireless power system of claim 13, wherein a repeater electromagnetic resonator is provided to deliver power from the first electromagnetic resonator to the second electromagnetic resonator.

17. The wireless power system of claim 13, wherein the repeater electromagnetic resonator is disposed under the skin of a patient.

18. The wireless power system of claim 13, wherein the repeater electromagnetic resonator is disposed in a wearable pack.