COIL UNIT AND APPARATUS FOR DETECTING FOREIGN MATTER

• US 20150145529A1
• Filed: 11/26/2014
• Published: 05/28/2015
• Est. Priority Date: 11/28/2013
• Status: Active Grant

• Current Assignee: TDK Corporation
• Original Assignee: TDK Corporation
• Inventors: URANO, Takashi
• Granted Patent: US 9,933,378 B2
• Time in Patent Office: Days
• US Class Current: 324/655
• CPC Class Codes: B60L 2270/147 electro magnetic [EMI]
• CPC Class Codes: B60L 53/124 Detection or removal of foreign bodies
• CPC Class Codes: G01N 27/025 a current being generated within the material by induction
• 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 50/60 responsive to the presence of foreign objects, e.g. detection of living beings
• 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 90/12 Electric charging stations
• CPC Class Codes: Y02T 90/14 Plug-in electric vehicles

Abstract

A power feeding coil unit (a coil unit) is provided with a power feeding coil (a coil for power transmission) and an apparatus for detecting foreign matter. The apparatus for detecting foreign matter is provided with a plurality of resonators having a resonator coil and capacitor and also an excitation coil for exciting the plurality of resonators. The plurality of resonators are disposed in rows and columns to cover at least an area interlinking with a magnetic flux generated by the power feeding coil. The excitation coil makes resonators adjacent in a row direction and a column direction among the plurality of resonators to generate an alternating magnetic field with resonance frequencies different from each other within a frequency band in which the power feeding coil is not excited.

Claims

1. A coil unit, which is used for a contactless power transmission from power feeding side to power receiving side,

comprising a coil for power transmission and an apparatus for detecting foreign matter,

wherein, the apparatus for detecting foreign matter comprises a plurality of resonators comprising a resonance coil and a resonance capacitor, and an excitation coil for exciting the plurality of resonators,

wherein, the plurality of resonators are disposed in rows and columns so as to cover at least an area interlinking with a magnetic flux generated by the coil for power transmission,

the excitation coil makes resonators adjacent with each other in a row direction and a column direction among the plurality of resonators to generate an alternating magnetic field with resonance frequencies different from each other within a frequency band in which the coil for power transmission is not excited.

2. The coil unit of claim 1, wherein,

the excitation coil makes one resonator and the resonators which is disposed surrounding it among the plurality of resonators, to generate an alternating magnetic field with resonance frequencies different from each other.

3. The coil unit of claim 1, wherein,

the apparatus for detecting foreign matter further comprises a plurality of detecting coils,

each of the plurality of detecting coils is disposed so as to be magnetically coupled to each resonator of the plurality of resonators.

5. The coil unit of claim 2, wherein,

the apparatus for detecting foreign matter further comprises a plurality of detecting coils,

each of the plurality of detecting coils is disposed so as to be magnetically coupled to each resonator of the plurality of resonators.

4. An apparatus for detecting foreign matter, which is used for detecting foreign matter, comprising a plurality of resonators having a resonance coil and a resonance capacitor, and an excitation coil for exciting the plurality of resonators,

wherein, the plurality of resonators are disposed in rows and columns in an in-plane direction,

wherein, the excitation coil makes resonators adjacent with each other in a row direction and a column direction among the plurality of resonators, to generate an alternating magnetic field with resonance frequencies different from each other of a frequency band.