Coil unit, contactless power transfer apparatus, vehicle, and contactless power feeding system

• US 9,225,204 B2
• Filed: 11/17/2011
• Issued: 12/29/2015
• Est. Priority Date: 11/18/2010
• Status: Active Grant

• Current Assignee: Nagoya Institute of Technology, Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Nagoya Institute of Technology, Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Ichikawa, Shinji, Kikuma, Nobuyoshi
• Primary Examiner(s): Fureman, Jared
• Assistant Examiner(s): Pham, Duc M
• Application Number:
  US13/885,869
• Publication Number:
  US 20130234509A1
• Time in Patent Office: 1,503 Days
• Field of Search: 307/104
• US Class Current: 1/1
• CPC Class Codes: B60L 2210/10 DC to DC converters
• CPC Class Codes: B60L 2210/30 AC to DC converters
• CPC Class Codes: B60L 2210/40 DC to AC converters
• CPC Class Codes: B60L 50/16 with provision for separate direct mechanical propulsion
• CPC Class Codes: B60L 50/40 using propulsion power supplied by capacitors
• 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 53/36 by positioning the vehicle
• CPC Class Codes: B60L 7/14 for vehicles propelled by ac motors
• 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 50/40 using two or more transmitting or receiving devices H02J50/50 takes precedence
• 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 second self-resonant coil electromagnetically resonating with a spaced, first self-resonant coil to perform at least one of transmitting power to the first self-resonant coil and receiving power from the first self-resonant coil, the second self-resonant coil including a first coil and a plurality of second coils provided inside the first coil, the direction of a magnetic field formed by the first coil is the same as those formed by the second coils.

Claims

1. A coil unit comprising a second self-resonant coil electromagnetically resonating with a spaced, first self-resonant coil to perform at least one of transmitting power to said first self-resonant coil and receiving power from said first self-resonant coil,

said second self-resonant coil including a first coil and a plurality of second coils provided inside said first coil,

a direction of a magnetic field formed by said first coil being the same as a direction of magnetic fields formed by said second coils.

2. The coil unit according to claim 1, wherein said second coils are mutually spaced.

3. The coil unit according to claim 1, wherein said first coil and said second coils are provided as a single-turn coil.

4. The coil unit according to claim 1, wherein said second self-resonant coil is formed of a single conducting wire.

5. The coil unit according to claim 1, wherein said second coils are inscribed in an inner circumferential portion of said first coil.

6. The coil unit according to claim 1, said second self-resonant coil being formed annularly with a centerline serving as a center, the coil unit further comprising an electromagnetic induction coil spaced from said second self-resonant coil along said centerline, wherein:

said second self-resonant coil includes a crossover that connects said first coil and said second coil together;

said crossover is bent to project toward said electromagnetic induction coil and thus cross over a portion of said second self-resonant coil; and

said electromagnetic induction coil includes a bent portion bent along said crossover to have a fixed distance to said second self-resonant coil.

7. The coil unit according to claim 1, said second self-resonant coil being formed annularly with a centerline serving as a center, the coil unit further comprising an electromagnetic induction coil spaced from said second self-resonant coil along said centerline, wherein:

said second self-resonant coil includes a crossover that connects said first coil and said second coil together; and

said crossover is bent to project in a direction opposite to said electromagnetic induction coil and thus cross over a portion of said second self-resonant coil.

8. The coil unit according to claim 1, said second self-resonant coil being formed annularly with a centerline serving as a center, the coil unit further comprising an electromagnetic induction coil spaced from said second self-resonant coil along said centerline, wherein when said second self-resonant coil and said electromagnetic induction coil are seen along said centerline, said electromagnetic induction coil and said first coil overlap each other.

9. A contactless power transfer apparatus comprising a coil unit according to claim 1.

10. A vehicle comprising:

a coil unit according to claim 1; and

a power storage device to store power.

11. A contactless power feeding system comprising:

a first coil unit including a first self-resonant coil; and

a second coil unit including a second self-resonant coil electromagnetically resonating with said first self-resonant coil to perform at least one of transmitting power and receiving power,

said first self-resonant coil including a first coil and a plurality of second coils provided inside said first coil,

said second self-resonant coil including a third coil and a plurality of fourth coils provided inside said third coil,

a direction of a magnetic field formed by said first coil being the same as a direction of magnetic fields formed by said second coils

a direction of a magnetic field formed by said third coil being the same as a direction of magnetic fields formed by said fourth coils.