COIL UNIT, POWER TRANSMISSION DEVICE, EXTERNAL POWER FEEDING APPARATUS, AND VEHICLE CHARGING SYSTEM

• US 20130335018A1
• Filed: 03/11/2011
• Published: 12/19/2013
• Est. Priority Date: 03/11/2011
• Status: Active Grant

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Ichikawa, Shinji
• Granted Patent: US 9,124,126 B2
• Time in Patent Office: Days
• US Class Current: 320/108
• CPC Class Codes: B60L 2210/10 DC to DC converters
• CPC Class Codes: B60L 2210/40 DC to AC converters
• CPC Class Codes: B60L 2270/147 electro magnetic [EMI]
• CPC Class Codes: B60L 50/16 with provision for separate direct mechanical propulsion
• CPC Class Codes: B60L 53/126 Methods for pairing a vehicle and a charging station, e.g. establishing a one-to-one relation between a wireless power transmitter and a wireless power receiver
• CPC Class Codes: B60L 53/30 Constructional details of charging stations
• CPC Class Codes: B60L 53/36 by positioning the vehicle
• CPC Class Codes: B60L 53/38 specially adapted for charging by inductive energy transfer
• 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 50/70 involving the reduction of electric, magnetic or electromagnetic leakage fields
• CPC Class Codes: H02J 50/90 involving detection or optimisation of position, e.g. alignment
• CPC Class Codes: H04B 5/26 using coils
• CPC Class Codes: H04B 5/79 for data transfer in combination with power transfer
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/7072 Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors
• CPC Class Codes: Y02T 10/72 Electric energy management in electromobility
• CPC Class Codes: Y02T 90/12 Electric charging stations
• CPC Class Codes: Y02T 90/14 Plug-in electric vehicles

Abstract

A coil unit includes a resonant coil establishing electromagnetic field resonant coupling with an external resonant coil provided external to a vehicle. The resonant coil includes an outer side coil extending along a circumference of a first winding center, centered about the first winding center, and an extension extending from the outer side coil into a region surrounded by the outer side coil. The resonant coil is formed such that an anti-node of the resonant coil that is an area of an anti-node of AC current flowing through the resonant coil, is located at the extension when electromagnetic field resonant coupling is established between the external resonant coil and the resonant coil.

Claims

1. A coil unit comprising:

a resonant coil establishing electromagnetic field resonant coupling with an external resonant coil provided external to a vehicle,

said resonant coil including an outer side coil extending along a circumference of a first winding center, centered about said first winding center, and an extension extending from said outer side coil into a region surrounded by said outer side coil,

said resonant coil formed such that an anti-node of the resonant coil that is an area of an anti-node of AC current flowing through said resonant coil, is located at said extension when electromagnetic field resonant coupling is established between said external resonant coil and said resonant coil.

2. The coil unit according to claim 1, wherein

said resonant coil includes an inner side coil formed in a loop, whose direction of a magnetic field developed by a flow of current is identical to the direction of the magnetic field developed by said outer side coil,

said extension is said inner side coil.

3. The coil unit according to claim 2, wherein

a plurality of said inner side coils are provided spaced apart along said outer side coil,

said anti-node is located at one of said plurality of inner side coils.

4. The coil unit according to claim 2, wherein

said inner side coil extends along a circumference of a second winding center,

said second winding center is located at a position distant from said first winding center,

said resonant coil is formed such that said anti-node is located closer to said first winding center than said second winding center.

5. The coil unit according to claim 1, wherein said resonant coil includes a first end and a second end,

further comprising a capacitor connected to said first and second ends,

said anti-node located at a middle of a conductor wire constituting said resonant coil in a length direction from one end to the other end of the conductor wire.

6. The coil unit according to claim 5, wherein

said resonant coil includes an inner side coil formed in a loop, whose direction of a magnetic field developed by a flow of current is identical to the direction of the magnetic field developed by said outer side coil,

a plurality of said inner side coils are provided spaced apart along said outer side coil,

said plurality of the inner side coils include a first inner side coil where the anti-node of said resonant coil is located, and a second inner side coil including said first end and second end, and to which said capacitor is connected.

7. The coil unit according to claim 5, wherein

said resonant coil and said capacitor constitute a resonant circuit,

said anti-node is located at a middle of a current path of said resonant circuit.

8. The coil unit according to claim 1, further comprising an electromagnetic induction coil coupled with said resonant coil in an electromagnetic induction manner.

9. A vehicle including a coil unit defined in claim 1, wherein a distance between the anti-node of said resonant coil and the center of said vehicle is smaller than the distance between said first winding center and the center of said vehicle.

10. An external power feeding apparatus comprising a coil unit defined in claim 1.

11. (canceled)

12. A vehicle power charging system comprising:

a vehicle including a coil unit, the coil unit including a resonant coil establishing electromagnetic field resonant coupling with an external resonant coil provided external to a vehicle,

said resonant coil including an outer side coil extending along a circumference of a first winding center, centered about said first winding center, and an extension extending from said outer side coil into a region surrounded by said outer side coil,

said resonant coil formed such that an anti-node of the resonant coil that is an area of an anti-node of AC current flowing through said resonant coil, is located at said extension when electromagnetic field resonant coupling is established between said external resonant coil and said resonant coil, wherein a distance between the anti-node of said resonant coil and the center of said vehicle is smaller than the distance between said first winding center and the center of said vehicle, and

an external power feeding apparatus including the coil unit.