Method and apparatus for wireless magnetic power transmission

• US 9,806,536 B2
• Filed: 10/11/2013
• Issued: 10/31/2017
• Est. Priority Date: 10/12/2012
• Status: Active Grant

• Current Assignee: Brigham and Women's Hospital Incorporated
• Original Assignee: Brigham and Women's Hospital Incorporated
• Inventors: Tang, Sai Chun
• Primary Examiner(s): Chang, Joseph
• Application Number:
  US14/432,330
• Publication Number:
  US 20150244178A1
• Time in Patent Office: 1,481 Days
• Field of Search: 307104
• CPC Class Codes: A61B 1/00029 externally powered, e.g. wireless
• CPC Class Codes: A61B 2560/0219 of externally powered implanted units
• CPC Class Codes: A61B 5/026 Measuring blood flow A61B3/1233, A61B3/1241 take precedence
• CPC Class Codes: A61N 1/37223 Circuits for electromagnetic coupling
• CPC Class Codes: A61N 1/3787 from an external energy source
• 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 2310/23 The load being a medical device, a medical implant, or a life supporting device
• CPC Class Codes: H02J 50/005 Mechanical details of housing or structure aiming to accommodate the power transfer means, e.g. mechanical integration of coils, antennas or transducers into emitting or receiving devices
• CPC Class Codes: H02J 50/10 using inductive coupling
• 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: H02J 7/0042 characterised by the mechanical construction

Abstract

Systems for wirelessly transmitting power to an implanted medical device. The wireless transmission system including a first and second transmitting coil both the first and second coil having substantially equal diameters and at least one conductor winding. A gap between the first transmitting second transmitting coil extending along a common axis by a distance equal to the radius of the first transmitting coil. A plurality of capacitors connected in series along the at least one conductor of the transmitting coils to divide the transmitting coils into a plurality of coil segments. An input connection is electronically coupled to the transmitting coils to deliver an excitation voltage to the transmitting coils to produce a substantially uniform magnetic field between the first transmitting coil and the second transmitting coil.

Claims

1. A system for wirelessly transferring energy to an implanted medical device, the system comprising:

a wireless power transmitting device, the wireless power transmitting device including;

a first transmitting coil having at least one conductor winding, a first radius and a first diameter;

a second transmitting coil having at least one conductor winding, a second radius, and a second diameter and arranged to extend along a common axis with the first transmitting coil, wherein the first diameter and the second diameter are substantially equal;

a gap arranged between the first transmitting coil and the second transmitting coil and extending along the common axis a distance equal to the first radius of the first transmitting coil;

a first plurality of capacitors connected in series along the at least one conductor winding of the first transmitting coil to divide the coil conductor winding into a first plurality of coil segments;

a second plurality of capacitors connected in series along the at least one conductor winding of the second transmitting coil to divide the coil conductor winding into a second plurality of coil segments; and

an input connection electrically coupled to the first transmitting coil and the second transmitting coil to deliver an excitation voltage to the first transmitting coil and the second transmitting coil substantially equal to a theoretical excitation voltage required to produce a substantially uniform magnetic field between the first transmitting coil and the second transmitting coil divided by a sum of the first plurality of coil segments and the second plurality of coil segments.

2. The system of claim 1, wherein the first transmitting coil and the second transmitting coil have a resonant frequency based on an operating frequency of less than 15 MHz.

3. The system of claim 1, wherein a number of the first plurality of capacitors and a number of the second plurality of capacitors are equal.

4. The system of claim 3, wherein the first plurality of coil segments and the second plurality of coil segments each include at least four equal coil segments.

5. The system of claim 1, wherein a voltage across each of the first plurality of capacitors and the second plurality of capacitors is equal and in opposite polarity to a voltage across each of the first plurality of coil segments and the second plurality of coil segments to substantially cancel the voltage across each of the first plurality of coil segments and second plurality of coil segments.

6. The system of claim 1, wherein a value of one of the first and second plurality of capacitors is determined by:

7. The system of claim 1, further comprising a power source coupled to the input connection and configured to deliver the excitation voltage to the input connection.

8. A system for wirelessly transferring energy to an implanted medical device, the system comprising:

a wireless power transmitting device, the wireless power transmitting device including;

a first transmitting coil having at least one conductor winding and a first radius and a first diameter;

a second transmitting coil having at least one conductor winding, a second radius, and a second diameter and arranged to extend along a common axis with the first transmitting coil, wherein the first diameter and the second diameter are substantially equal;

a gap arranged between the first transmitting coil and the second transmitting coil and extending along the common axis a distance equal to the first radius of the first transmitting coil;

a first plurality of capacitors connected in series along the at least one conductor winding of the first transmitting coil to divide the coil conductor winding into a first plurality of coil segments;

a second plurality of capacitors connected in series along the at least one conductor winding of the second transmitting coil to divide the coil conductor winding into a second plurality of coil segments; and

a power source electrically coupled to the first transmitting coil and the second transmitting coil and configured to deliver an excitation voltage to the first transmitting coil and the second transmitting coil substantially equal to a theoretical excitation voltage required to produce a substantially uniform magnetic field between the first transmitting coil and the second transmitting coil divided by a sum of the first plurality of coil segments and the second plurality of coil segments.

9. The system of claim 8, wherein the first transmitting coil and the second transmitting coil have a resonant frequency based on an operating frequency of the wireless transmission device and further comprising a wireless power receiving device, the wireless power receiving device including:

a receiving coil;

a plurality of capacitors;

the wireless power receiving device having a resonant frequency equal to the operating frequency of the wireless power transmitting device; and

wherein the wireless power receiving device is configured to convert the magnetic field generated by the wireless power transmitting device into electrical power.

10. The system of claim 8, wherein the receiving coil includes an air core.

11. A system for wirelessly transferring energy to an implanted medical device, the system comprising:

a wireless power transmitting device, the wireless power transmitting device including;

a first transmitting coil and a second transmitting coil;

the first transmitting coil and the second transmitting coil each having at least one conductor winding;

the first transmitting coil and the second transmitting coil being substantially equal in diameter;

the first transmitting coil and the second transmitting coil are located parallel to each other and separated co-axially by a distance equal to a radius of the first transmitting coil;

wherein the first transmitting coil conductor winding and the second transmitting coil conductor winding include a plurality of capacitors connected in series and further wherein the series capacitors are installed along the first transmitting coil conductor winding and the second transmitting coil conductor winding to divide the coil conductor winding into a plurality of coil segments;

the first transmitting coil and the second transmitting coil having a resonant frequency based on an operating frequency of the wireless power transmitting device; and

wherein the wireless power transmitting device is configured to produce a uniform magnetic field between the first transmitting coil and the second transmitting coil when an excitation voltage is applied to the wireless power transmitting device;

a wireless power receiving device, the wireless power receiving device including;

a receiving coil;

a plurality of capacitors;

the wireless power receiving device having a resonant frequency equal to the operating frequency of the wireless power transmitting device; and

wherein the wireless power receiving device is configured to convert the magnetic field generated by the wireless power transmitting device into electrical power.

12. The system of claim 11, wherein the first transmitting coil and the second transmitting coil have a resonant frequency based on an operating frequency of less than 15 MHz.

13. The system of claim 11, wherein a number of the first plurality of capacitors and a number of the second plurality of capacitors are equal.

14. The system of claim 13, wherein the first plurality of coil segments and the second plurality of coil segments each include at least four equal coil segments.

15. The system of claim 11, wherein a voltage across each of the first plurality of capacitors and the second plurality of capacitors is equal and in opposite polarity to a voltage across each of the first plurality of coil segments and the second plurality of coil segments to substantially cancel the voltage across each of the first plurality of coil segments and second plurality of coil segments.

16. The system of claim 11, wherein a value of one of the first and second plurality of capacitors is determined by:

17. The system of claim 11, further comprising a power source coupled to the input connection and configured to deliver the excitation voltage to the input connection.