Space-adaptive wireless power transfer system and method using evanescent field resonance

• US 9,786,430 B2
• Filed: 09/17/2010
• Issued: 10/10/2017
• Est. Priority Date: 11/04/2009
• Status: Active Grant

• Current Assignee: Korea Electrotechnology Research Institute
• Original Assignee: Korea Electrotechnology Research Institute
• Inventors: Park, Young Jin, Lee, Soon Wo, Kang, Ji Myung, Kim, Jin Wook, Kim, Kwan Ho
• Primary Examiner(s): Barnie, Rexford
• Assistant Examiner(s): Ortiz, Elim
• Application Number:
  US13/508,345
• Publication Number:
  US 20120286584A1
• Time in Patent Office: 2,580 Days
• Field of Search: 307104
• CPC Class Codes: H01F 27/006 with special arrangement or spacing of turns of the winding(s), e.g. to produce desired self-resonance
• 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 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: H03H 7/38 Impedance-matching networks

Abstract

A magnetic resonance wireless power transfer method according to an aspect of the present invention includes transmitting power from a source coil to the Tx resonant coil using a magnetic induction method, transmitting the power from the Tx resonant coil to an Rx resonant coil, having a resonant frequency identical with that of the Tx resonant coil, via magnetically-coupled resonance, and transmitting the power from the Rx resonant coil to the device coil of an electronic device using the magnetic induction method. The Tx resonant coil and the Rx resonant coil are arranged at a right angle or a specific angle of inclination relative to each other.

Claims

1. A magnetic resonance wireless power transfer method, comprising:

transferring power from a source coil to a transmitting (Tx) resonant coil using a magnetic induction method;

transferring the power from the Tx resonant coil to a receiving (Rx) resonant coil, having a resonant frequency identical with that of the Tx resonant coil, via magnetically-coupled resonance of magnetic evanescent field with non-directive property; and

transferring the power from the Rx resonant coil to a device coil of an electronic device using the magnetic induction method;

wherein in order to transfer the power irrespective of directionality, the Tx resonant coil and the Rx resonant coil are arranged at a right angle or a specific angle of inclination relative to each other so that center axes of the Tx resonant coil and the Rx resonant coil are not parallel to each other, and

wherein impedance matching at the source coil is performed by controlling the number of turns or size of the source coil or the interval between the source coil and the Tx resonant coil at a specific resonant frequency of the Tx resonant coil, or impedance matching at the device coil is performed by controlling the number of turns or size of the device coil or the interval between the device coil and the Rx resonant coil at the specific resonant frequency of the Rx resonant coil.

2. A magnetic resonance wireless power transfer method, comprising:

transferring power from a source coil to a Tx resonant coil using a magnetic induction method;

transferring the power from the Tx resonant coil to an intermediate resonant coil, having a resonant frequency identical with that of the Tx resonant coil, via magnetically-coupled resonance;

transferring the power from the intermediate resonant coil to an Rx resonant coil, having a resonant frequency identical with the Rx resonant coil, via magnetically-coupled resonance; and

transferring the power from the Rx resonant coil to a device coil of an electronic device using a magnetic induction method;

wherein the intermediate resonant coil is placed at a right angle or an angle of inclination relative to the Tx resonant coil and the Rx resonant coil, and

wherein impedance matching at the source coil is performed by controlling the number of turns or size of the source coil or the interval between the source coil and the Tx resonant coil at a specific resonant frequency of the Tx resonant coil.

3. A magnetic resonance wireless power transfer system, comprising:

a source coil configured to be supplied with power from a source;

a Tx resonant coil configured to be supplied with the power from the source coil using a magnetic induction method; and

an Rx resonant coil configured to be supplied with the power from the Tx resonant coil at a resonant frequency identical with that of the Tx resonant coil via magnetically-coupled resonance of magnetic evanescent field with non-directive property,

wherein in order to transfer the power irrespective of directionality, the Tx resonant coil and the Rx resonant coil are arranged at a right angle or a specific angle of inclination relative to each other so that center axes of the Tx resonant coil and the Rx resonant coil are not parallel to each other, and the Rx resonant coil transfers the power to a device coil of an electronic device using the magnetic induction method, and

wherein impedance matching at the source coil is performed by controlling the number of turns or size of the source coil or the interval between the source coil and the Tx resonant coil at a specific resonant frequency of the Tx resonant coil, or impedance matching at the device coil is performed by controlling the number of turns or size of the device coil or the interval between the device coil and the Rx resonant coil at the specific resonant frequency of the Rx resonant coil.

4. The magnetic resonance wireless power transfer system as set forth in claim 3, further comprising at least one of an impedance matching circuit between the source and the source coil, an impedance matching circuit between the device coil and a rectifier circuit of the electronic device, and an impedance matching circuit between the device coil and load of the electronic device.

5. The magnetic resonance wireless power transfer system as set forth in claim 3, wherein at least one of the Tx resonant coil and the Rx resonant coil comprises:

a lumped inductor or capacitor whose two electrodes are connected between both ends of the at least one coil, or whose only one electrode is connected to one of both ends of the at least one coil, to both ends of the at least one coil, or to an intermediate portion of the at least one coil.

6. The magnetic resonance wireless power transfer system as set forth in claim 3, wherein the Tx resonant coil is embedded in a wall or a board, the Rx resonant coil is embedded in a desk or a table, a space, another wall, a pad, or a container near the wall, and the electronic device near the Rx resonant coil is supplied with the power.

7. The magnetic resonance wireless power transfer system as set forth in claim 3, wherein the Tx resonant coil or the Rx resonant coil has a helical or spiral form.

8. The magnetic resonance wireless power transfer system as set forth in claim 4, wherein the impedance matching circuit includes a coaxial cable to provide a capacitance value.

9. The magnetic resonance wireless power transfer system as set forth in claim 5, wherein a sum of a capacitance of the at least one coil itself to which the capacitor is additionally coupled and a capacitance of the added capacitor is equal to or higher than 100 pF and equal to or lower than 10 nF.

10. The magnetic resonance wireless power transfer system as set forth in claim 7, wherein the Tx resonant coil or the Rx resonant coil has a form in which a wire is wound around a magnetic body.

11. A magnetic resonance wireless power transfer system, comprising:

a source coil configured to be supplied with power from a source;

a Tx resonant coil configured to be supplied with the power from the source coil using a magnetic induction method;

an intermediate resonant coil supplied with power from the Tx resonant coil at a resonant frequency identical with that of the Tx resonant coil using a magnetic resonance mechanism; and

an Rx resonant coil configured to be supplied with the power from the intermediate resonant coil at a resonant frequency identical with that of the intermediate resonant coil via magnetically-coupled resonance,

wherein the intermediate resonant coil is placed at a right angle or an angle of inclination relative to the Tx resonant coil and the Rx resonant coil, and the Rx resonant coil transfers the power to a device coil of an electronic device using a magnetic induction method, and

wherein impedance matching at the source coil is performed by controlling the number of turns or size of the source coil or the interval between the source coil and the Tx resonant coil at a specific resonant frequency of the Tx resonant coil.

12. The magnetic resonance wireless power transfer system as set forth in claim 11, wherein at least one of the Tx resonant coil, the Rx resonant coil, and the intermediate resonant coil comprises;

a lumped inductor or a capacitor whose two electrodes are connected between both ends of the at least one coil, or whose only one electrode is connected to one of both ends of the at least one coil, to both ends of the at least one coil, or to an intermediate portion of the at least one coil.

13. The magnetic resonance wireless power transfer system as set forth in claim 11, wherein the Tx resonant coil, the Rx resonant coil, or the intermediate resonant coil has a helical or spiral form.

14. The magnetic resonance wireless power transfer system as set forth in claim 11, wherein the Tx resonant coil directly transfers the power to the Rx resonant coil and simultaneously the intermediate resonant coil transfers the stored power to the Rx resonant coil.

15. The magnetic resonance wireless power transfer system as set forth in claim 11, wherein the Rx resonant coil transfers the power to the device coil of the electronic device using the magnetic induction method, and simultaneously the intermediate resonant coil transfers the power to a device coil of another electronic device using the magnetic induction method.

16. The magnetic resonance wireless power transfer system as set forth in claim 11, further comprising an impedance matching circuit between the source and the source coil, or the device coil and a rectifier circuit or load of the electronic device.

17. The magnetic resonance wireless power transfer system as set forth in claim 11, wherein impedance matching at the device coil is performed by controlling the number of turns or size of the device coil or the interval between the device coil and the Rx resonant coil at the specific resonant frequency of the Rx resonant coil, even without using an impedance matching circuit.

18. The magnetic resonance wireless power transfer system as set forth in claim 12, wherein a sum of a capacitance of the at least one coil itself to which the capacitor is additionally coupled and a capacitance of the added capacitor is equal to or higher than 100 pF and equal to or lower than 10 nF.

19. The magnetic resonance wireless power transfer system as set forth in claim 11, wherein the Tx resonant coil is embedded in a wall or a board, the Rx resonant coil is embedded in a desk or a table, a space, another wall, a pad, or a container near the wall, and the electronic device near the Rx resonant coil is supplied with the power.

20. The magnetic resonance wireless power transfer system as set forth in claim 11, wherein the Tx resonant coil, the intermediate resonant coil and the Rx resonant coil are arranged so that the center axes of the Tx resonant coil, the intermediate resonant coil and the Rx resonant coil are parallel to each other, but the center axes are not identical with each other.

21. The magnetic resonance wireless power transfer system as set forth in claim 13, wherein the Tx resonant coil, the Rx resonant coil, or the intermediate resonant coil has a form in which a wire is wound around a magnetic body.