Automatic power regulation for transcutaneous energy transfer charging system

• US 9,002,468 B2
• Filed: 12/16/2011
• Issued: 04/07/2015
• Est. Priority Date: 12/16/2011
• Status: Active Grant

• Current Assignee: Abiomed, Inc. (Johnson & Johnson)
• Original Assignee: Abiomed, Inc. (Johnson & Johnson)
• Inventors: Shea, Arthur, Ambrosio, Ralph D.
• Primary Examiner(s): Gedeon, Brian T
• Assistant Examiner(s): TEJANI, ANKIT D
• Application Number:
  US13/328,568
• Publication Number:
  US 20130158631A1
• Time in Patent Office: 1,208 Days
• Field of Search: None
• US Class Current: 607/61
• CPC Class Codes: A61M 60/178 drawing blood from a ventricle and returning the blood to the arterial system via a cannula external to the ventricle, e.g. left or right ventricular assist devices
• CPC Class Codes: A61M 60/216 including a rotating member acting on the blood, e.g. impeller
• CPC Class Codes: A61M 60/873 specially adapted for wireless or transcutaneous energy transfer [TET], e.g. inductive charging
• CPC Class Codes: A61N 1/3787 from an external energy source

Abstract

Methods and systems for controlling power output from an external power source in a transcutaneous energy transfer (TET) system are provided to prevent inadvertent energy transfer when no secondary coil is present. The system operates by transmitting power transcutaneously from an external primary coil and determining whether a response from a secondary coil implanted within a patient is detected. If no response is detected, the power output of the primary coil is decreased. The decrease in power output can be accomplished by operating the primary coil at a lower average power level, which can include variations in power level, duty cycle, etc. The system can also be configured to periodically repeat the process in order to continue searching for a coupled secondary coil.

Claims

1. A method of controlling power output from a primary coil in a transcutaneous energy transfer system, comprising:

transcutaneously transmitting power from the primary coil;

determining whether a response from a secondary coil within a patient is detected; and

if no response from the secondary coil is detected, decreasing the power output of the primary coil.

2. The method of claim 1, wherein the step of decreasing the power output of the primary coil comprises reducing an average power output of the primary coil.

3. The method of claim 2, wherein the step of reducing the average power output of the primary coil is accomplished by varying a duty cycle of the primary coil.

4. The method of claim 2, wherein the step of reducing the average power output of the primary coil is accomplished by reducing the power output of the primary coil by a percentage value.

5. The method of claim 4, wherein the percentage value is large enough to prevent inadvertent heating of a nearby object.

6. The method of claim 1, wherein the method further comprises waiting a first period of time before determining that the response has not been received.

7. The method of claim 1, wherein the method further comprises holding or adjusting the power output of the primary coil in response to requirements of the secondary coil if the response from the secondary coil is received.

8. The method of claim 6, wherein the first period of time is 100 milliseconds.

9. The method of claim 6, wherein the power output of the primary coil is reduced to zero after the first period of time elapses.

10. The method of claim 6, wherein the power output of the primary coil is decreased at a linear rate after the first period of time elapses.

11. The method of claim 6, further comprising:

holding the power output of the primary coil at a decreased level for a second period of time if the response is not received during the first period of time; and

after the second period of time elapses;

transcutaneously transmitting power from the primary coil;

determining whether the response from the secondary coil is detected; and

if no response is received, decreasing the power output of the primary coil.

12. The method of claim 11, wherein the decreased level of the power output is zero.

13. The method of claim 11, wherein the second period of time is 3 seconds.

14. The method of claim 1, wherein the response from the secondary coil is in a form of one or more detectable feedback indications.

15. A method of controlling power output from a primary coil in a transcutaneous energy transfer system, comprising:

transcutaneously transmitting power from the primary coil;

determining whether a response from a secondary coil within a patient is detected; and

if no response is detected, reducing an average power output of the primary coil while the primary coil and the secondary coil are de-coupled.

16. The method of claim 15, wherein the response from an implanted medical device is in a form of one or more detectable feedback indications.

17. The method of claim 15, wherein the step of reducing the average power output is accomplished by varying a duty cycle of the primary coil.

18. The method of claim 15, wherein the step of reducing the average power output is accomplished by reducing the power output of the primary coil by a percentage value.

19. The method of claim 15, wherein the average power output is reduced to zero power.

20. The method of claim 15, further comprising:

holding the average power output of the primary coil at a decreased level for a period of time, and then,

transcutaneously transmitting power from the primary coil;

determining whether the response from the secondary coil is detected; and

if no response is received, reducing the average power output of the primary coil.