Resonant power transfer system and method of estimating system state

• US 10,525,181 B2
• Filed: 07/29/2013
• Issued: 01/07/2020
• Est. Priority Date: 07/27/2012
• Status: Active Grant

• Current Assignee: TC1 LLC (Abbott Laboratories Incorporated)
• Original Assignee: TC1 LLC (Abbott Laboratories Incorporated)
• Inventors: Petersen, Ethan
• Primary Examiner(s): Borroto, Alfonso Perez
• Application Number:
  US14/414,823
• Publication Number:
  US 20150207331A1
• Time in Patent Office: 2,353 Days
• Field of Search: 307104
• CPC Class Codes: A61M 60/122 Implantable pumps or pumping devices, i.e. the blood being pumped inside the patient's body
• 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 60/20 Type thereof
• 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: H02J 2310/23 The load being a medical device, a medical implant, or a life supporting device
• CPC Class Codes: H02J 50/10 using inductive coupling
• CPC Class Codes: H02J 50/12 of the resonant type
• 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

Abstract

Systems for tuning a wireless power transfer system are provided, which may include any number of features. In one embodiment, a wireless power transfer system can include a transmit controller connected to the transmitter resonator and configured to measure an impedance on the transmitter resonator. The transmit controller can be configured to determine a load resistance of the receiver resonator and a coupling coefficient between the transmitter and receiver resonators based on the measured impedance on the transmitter resonator. The transmit controller can be further configured to adjust a power transmission parameter of the transmitter resonator based on the determined load resistance and the coupling coefficient to achieve a controlled voltage at a load of the receiver. Methods of use are also provided.

Claims

1. A method of tuning and controlling a wireless power system, comprising the steps of:

measuring an impedance on a transmitter resonator;

determining a load resistance of a receiver resonator and a coupling coefficient between the transmitter and receiver resonators by deriving the load resistance and the coupling coefficient from the measured impedance using a look up table that specifies i) how a real-part of the measured impedance changes as a function of variations in the load resistance and variations in the coupling coefficient and ii) how an imaginary part of the measured impedance changes as a function of variations in the load resistance and variations in the coupling coefficient; and

adjusting a power transmission parameter of the transmitter resonator based on the determined load resistance and the coupling coefficient to achieve a controlled voltage at a load of the receiver.

2. The method of claim 1 wherein the step of measuring the impedance on the transmitter resonator comprises measuring the impedance on the transmitter resonator with a controller of the transmitter resonator.

3. The method of claim 1 wherein the power transmission parameter comprises a power level of the transmitter resonator.

4. The method of claim 1 wherein the power transmission parameter comprises a frequency of the transmitter resonator.

5. The method of claim 1 wherein the power transmission parameter comprises a voltage of the transmitter resonator.

6. The method of claim 1 wherein the power transmission parameter comprises a value of a capacitor in the transmitter resonator circuit.

7. The method of claim 1 wherein the power transmission parameter comprises a value of an inductor in the transmitter resonator circuit.

8. The method of claim 1 further comprising transmitting wireless power from the transmitter resonator to the receiver resonator.

9. The method of claim 8 further comprising transmitting wireless power into the body of a patient.

10. A wireless power system, comprising:

a transmitter resonator configured to transmit wireless power to a receiver resonator;

a transmit controller connected to the transmitter resonator and configured to measure an impedance on the transmitter resonator, the transmit controller configured to determine a load resistance of the receiver resonator and a coupling coefficient between the transmitter and receiver resonators by deriving the load resistance and the coupling coefficient from the measured impedance on the transmitter resonator using a look up table that specifies i) how a real-part of the measured impedance changes as a function of variations in the load resistance and variations in the coupling coefficient and ii) how an imaginary part of the measured impedance changes as a function of variations in the load resistance and variations in the coupling coefficient, the transmit controller further configured to adjust a power transmission parameter of the transmitter resonator based on the determined load resistance and the coupling coefficient to achieve a controlled voltage at a load of the receiver.

11. The system of claim 10, wherein the power transmission parameter comprises a power level of the transmitter resonator.

12. The system of claim 10, wherein the power transmission parameter comprises a frequency of the transmitter resonator.

13. The system of claim 10, wherein the power transmission parameter comprises a voltage of the transmitter resonator.

14. The system of claim 10, wherein the power transmission parameter comprises a value of a capacitor in the transmitter resonator circuit.

15. The system of claim 10, wherein the power transmission parameter comprises a value of an inductor in the transmitter resonator circuit.

16. The system of claim 10, wherein the receiver resonator is adapted to be implanted within a body of a patient, and the transmitter resonator is configured to transmit wireless power into the receiver resonator in the body of the patient.