Contactless power transmission device, and power feeder and power receiver for use in the same

• US 9,704,643 B2
• Filed: 03/06/2014
• Issued: 07/11/2017
• Est. Priority Date: 10/28/2011
• Status: Active Grant

• Current Assignee: Panasonic Automotive Systems Company of America (Panasonic Holdings Corporation)
• Original Assignee: Panasonic Intellectual Property Management Co., Ltd. (Panasonic Holdings Corporation)
• Inventors: Sakamoto, Yoshihiro, Kurihara, Hiroaki, Fujita, Atsushi
• Primary Examiner(s): Johnson, Ryan
• Application Number:
  US14/199,283
• Publication Number:
  US 20140183970A1
• Time in Patent Office: 1,223 Days
• CPC Class Codes: B60L 2200/26 Rail vehicles
• CPC Class Codes: B60L 2210/30 AC to DC converters
• CPC Class Codes: B60L 2210/40 DC to AC converters
• CPC Class Codes: B60L 2240/36 Temperature of vehicle components or parts
• CPC Class Codes: B60L 2250/10 by alarm
• CPC Class Codes: B60L 2250/16 by display
• CPC Class Codes: B60L 2270/147 electro magnetic [EMI]
• CPC Class Codes: B60L 53/122 Circuits or methods for driving the primary coil, e.g. supplying electric power to the coil
• CPC Class Codes: B60L 53/124 Detection or removal of foreign bodies
• 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 53/305 Communication interfaces
• CPC Class Codes: B60L 53/36 by positioning the vehicle
• CPC Class Codes: B60L 53/65 involving identification of vehicles or their battery types
• CPC Class Codes: G01R 27/2605 Measuring capacitance capacitive sensors G01D5/24
• 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 2310/48 for electric vehicles [EV] or hybrid vehicles [HEV]
• CPC Class Codes: H02J 50/10 using inductive coupling
• CPC Class Codes: H02J 50/60 responsive to the presence of foreign objects, e.g. detection of living beings
• 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
• CPC Class Codes: H02J 7/00034 : Charger exchanging data with an electronic device, i.e. telephone, whose internal battery is under charge
• CPC Class Codes: H04B 5/26 : using coils
• CPC Class Codes: H04B 5/72 : for local intradevice communication
• 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
• CPC Class Codes: Y02T 90/16 : Information or communication technologies improving the operation of electric vehicles
• CPC Class Codes: Y02T 90/167 : Systems integrating technologies related to power network operation and communication or information technologies for supporting the interoperability of electric or hybrid vehicles, i.e. smartgrids as interface for battery charging of electric vehicles [EV] or hybrid vehicles [HEV]
• CPC Class Codes: Y04S 30/14 : Details associated with the interoperability, e.g. vehicle recognition, authentication, identification or billing

Abstract

A power feeder of a contactless power transmission device includes a housing base member, a primary coil provided on the housing base member and configured to generate magnetic flux, a cover attached to the housing base member and configured to cover the primary coil, a capacitance sensor including a detection electrode between the primary coil and the cover, and configured to detect foreign matter around the cover based on a change in capacitance detected using the detection electrode, and a high-dielectric member embedded in the cover and having a permittivity higher than that of a material for the cover.

Claims

1. A contactless power transmission device for transmitting power between a power feeder and a power receiver via electromagnetic induction, wherein

the power feeder includes:

a housing base member,

a primary coil provided on the housing base member and configured to generate magnetic flux,

a cover attached to the housing base member and configured to cover the primary coil,

a capacitance sensor including a detection electrode between the primary coil and the cover, and configured to detect foreign matter around the cover based on a change in capacitance detected using the detection electrode,

a high-dielectric member embedded in the cover and having a permittivity higher than that of a material for the cover, and

wherein the cover has an upper portion configured to cover an upper portion of the primary coil and a side portion configured to cover a side portion of the primary coil,

the detection electrode is provided between the upper portion of the cover and the primary coil and between the side portion of the cover and the primary coil, and

the high-dielectric member is embedded in the upper and side portions of the cover.

2. The contactless power transmission device of claim 1, wherein the high-dielectric member is provided in a range overlapping the corresponding detection electrode in a direction of the magnetic flux.

3. The contactless power transmission device of claim 1, wherein

there are a plurality of the detection electrodes arranged at a predetermined pitch, and

the high-dielectric member is arranged to correspond to each of the detection electrodes.

4. The contactless power transmission device of claim 1, wherein

the high-dielectric member is radially arranged along a surface of the cover, extending outward from a center of the cover, and

the detection electrode is arranged to correspond to the high-dielectric member.

5. The contactless power transmission device of claim 1, wherein the high-dielectric member embedded in the cover has a higher density at a location where the amount of passing magnetic flux is large than at a location where the amount of passing magnetic flux is small.

6. The contactless power transmission device of claim 1, wherein a front surface of the detection electrode is in contact with a back surface of the cover.

7. The contactless power transmission device of claim 6, further comprising:

a support member configured to support the detection electrode so that the detection electrode is in contact with the back surface of the cover.

8. The contactless power transmission device of claim 7, wherein the support member includes a position adjustment portion configured to, when a pressure load is externally applied to the cover and then is removed, adjust the detection electrode so that the detection electrode comes into contact with the back surface of the cover at an original position thereof.

9. A contactless power transmission device for transmitting power between a power feeder and a power receiver via electromagnetic induction, wherein

the power receiver includes:

a housing base member,

a secondary coil provided on the housing base member and configured to generate electromotive force depending on magnetic flux received from the power feeder,

a cover attached to the housing base member and configured to cover the secondary coil,

a capacitance sensor including a detection electrode between the secondary coil and the cover, and configured to detect foreign matter around the cover based on a change in capacitance detected using the detection electrode, and

a high-dielectric member embedded in the cover and having a permittivity higher than that of the cover, and

wherein the cover has an upper portion configured to cover an upper portion of the primary coil and a side portion configured to cover a side portion of the primary coil,

the detection electrode is provided between the upper portion of the cover and the primary coil and between the side portion of the cover and the primary coil, and

the high-dielectric member is embedded in the upper and side portions of the cover.

10. A power feeder for feeding power to a power receiver of a contactless power transmission device via electromagnetic induction when the power feeder and the power receiver are positioned to face each other, the power feeder comprising:

a housing base member;

a primary coil provided on the housing base member and configured to generate magnetic flux;

a cover attached to the housing base member and configured to cover the primary coil;

a capacitance sensor including a detection electrode between the primary coil and the cover, and configured to detect foreign matter around the cover based on a change in capacitance detected using the detection electrode; and

a high-dielectric member embedded in the cover and having a permittivity higher than that of a material for the cover,

wherein the cover has an upper portion configured to cover an upper portion of the primary coil and a side portion configured to cover a side portion of the primary coil,

the detection electrode is provided between the upper portion of the cover and the primary coil and between the side portion of the cover and the primary coil, and

the high-dielectric member is embedded in the upper and side portions of the cover.

11. A power receiver for receiving power from a power feeder of a contactless power transmission device, the power receiver comprising:

a housing base member;

a secondary coil provided on the housing base member and configured to generate electromotive force depending on magnetic flux received from the power feeder;

a cover attached to the housing base member and configured to cover the secondary coil;

a capacitance sensor including a detection electrode between the secondary coil and the cover, and configured to detect foreign matter around the cover based on a change in capacitance detected using the detection electrode; and

a high-dielectric member embedded in the cover and having a permittivity higher than that of the cover,

wherein the cover has an upper portion configured to cover an upper portion of the primary coil and a side portion configured to cover a side portion of the primary coil,

the detection electrode is provided between the upper portion of the cover and the primary coil and between the side portion of the cover and the primary coil, and

the high-dielectric member is embedded in the upper and side portions of the cover.