Apparatus and method for identifying foreign bodies in an inductive charging system

• US 9,778,204 B2
• Filed: 02/27/2015
• Issued: 10/03/2017
• Est. Priority Date: 08/30/2012
• Status: Active Grant

• Current Assignee: Bayerische Motoren Werke AG
• Original Assignee: Bayerische Motoren Werke AG
• Inventors: Goethel, Joachim
• Primary Examiner(s): Tso, Edward
• Assistant Examiner(s): Piggush, Aaron
• Application Number:
  US14/633,214
• Publication Number:
  US 20150168309A1
• Time in Patent Office: 949 Days
• Field of Search: 320104, 320108, 320109
• CPC Class Codes: B60L 2250/10 by alarm
• 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 53/37 using optical position determination, e.g. using cameras
• CPC Class Codes: B60L 53/38 specially adapted for charging by inductive energy transfer
• CPC Class Codes: G01N 21/8851 Scan or image signal processing specially adapted therefor, e.g. for scan signal adjustment, for detecting different kinds of defects, for compensating for structures, markings, edges G01N21/8806 and G01N21/93 - G01N21/95692 take precedence; optical measurement of dimensions G01B11/00; optical scanning G02B26/10; image transformation G06T3/00; computerised image enhancement G06T5/00; image processing per se for flaw detection G06T7/0002
• CPC Class Codes: G01N 2201/12 Circuits of general importance; Signal processing
• 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
• CPC Class Codes: Y02T 90/16 Information or communication technologies improving the operation of electric vehicles

Abstract

An apparatus and method for identifying foreign objects in an inductive charging system having a charging unit and a vehicle for inductive charging, in which the charging unit includes a primary coil and the vehicle has a secondary coil in order to transmit electrical power from the primary coil to the secondary coil during a charging operation. The vehicle includes a camera system, and a camera control unit. The camera system captures at least one image of the charging unit when the vehicle approaches the charging unit, at the beginning of a charging operation and/or during a charging operation. The camera control unit digitally processes the at least one captured image in order to detect a foreign body located on the charging unit.

Claims

1. An apparatus for identifying a foreign body in an inductive charging system, the inductive charging system comprising a charging unit having a primary coil and a vehicle having a secondary coil, wherein electrical power is transmitted from the primary coil to the secondary coil during a charging operation, the apparatus comprising:

a camera system of the vehicle; and

a camera control unit coupled to the camera system, wherein

the camera system is configured to capture at least one image of the charging unit as the vehicle approaches the charging unit and before the vehicle reaches a charging position of the charging operation, and

the camera control unit digitally processes the at least one captured image in order to detect the foreign body located on the charging unit.

2. The apparatus according to claim 1, wherein:

the charging unit comprises a charging control device,

the primary coil of the charging unit is controllable by the charging control device, and

at least one unidirectional data connection is establishable from the camera control unit to the charging control device.

3. The apparatus according to claim 2, wherein:

the camera control unit generates a detection signal when a foreign body is detected, and

the detection signal is transmitted from the camera control unit to the charging control device via the established data connection.

4. The apparatus according to claim 3, wherein when the detection signal is received by the charging control device, the charging control device suppresses, interrupts or reduces power transmission from the primary coil to the secondary coil.

5. The apparatus according to claim 4, wherein:

the charging unit further comprises an information unit; and

when the detection signal is received by the charging control device, the information unit outputs a warning signal.

6. The apparatus according to claim 3, wherein:

the charging unit further comprises an information unit; and

when the detection signal is received by the charging control device, the information unit outputs a warning signal.

7. The apparatus according to claim 3, wherein

the vehicle includes a communications unit,

the detection signal is transmitted from the camera control unit to the communications unit, and

when the detection signal is received by the communications unit, the communications unit outputs a warning signal.

8. The apparatus according to claim 1, wherein:

a referenced image of the charging unit without a foreign body on the charging unit is stored in the camera control unit,

the camera control unit compares the at least one captured image with the referenced image, and

a deviation of the captured image from the referenced image identifies a detection of a foreign body.

9. The apparatus according to claim 8, wherein the camera control unit carries out the image comparison using a segmenting method or a pattern recognition method.

10. The apparatus according to claim 1, wherein the camera system and the camera control unit also function as a driver assistant system of the vehicle.

11. The apparatus according to claim 1, wherein the camera system is further configured to capture at least one image of the charging unit when the vehicle is in the charging position at a beginning of the charging operation.

12. The apparatus according to claim 11, wherein the camera system is further configured to capture at least one image of the charging unit when the vehicle is in the charging position during the charging operation.

13. A method of identifying a foreign body in an inductive charging system comprising a charging unit having a primary coil and a vehicle having a secondary coil, electrical power being inductively transmitted from the primary coil to the secondary coil during a charging operation, the method comprising the acts of:

obtaining, via a camera system arranged on the vehicle, at least one image of the charging unit as the vehicle approaches the charging unit and before the vehicle reaches a charging position of the charging operation; and

digitally processing the obtained at least one image of the charging unit in order to determine whether a foreign body is located on the charging unit.

14. The method according to claim 13, further comprising the acts of:

generating, via the camera system, a detection signal when a foreign body is identified on the charging unit;

transmitting the detection signal from the camera system of the vehicle to a charging control device outside of the vehicle; and

interrupting or reducing the electrical power being transmitted, via the charging control device, when the detection signal is received.

15. The method according to claim 14, further comprising the act of outputting a warning signal via the charging control device when the detection signal is received.

16. The method according to claim 13, further comprising the act of outputting a warning signal to a driver inside the vehicle upon identifying a foreign body located on the charging unit.

17. The method according to claim 13, further comprising the acts of:

storing, in the camera system, a reference image of the charging unit without a foreign body located on the charging unit;

comparing, via the camera system, the at least one obtained image with the reference image; and

determining the existence of a foreign body based on a deviation of the obtained image from the referenced image.

18. The method according to claim 17, wherein the camera system performs the comparison using a segmenting method or a pattern recognition method.

19. The method according to claim 17, wherein obtaining, via the camera system arranged on the vehicle, at least one image of the charging unit further comprises obtaining, via the camera system, at least one image of the charging unit when the vehicle is in the charging position at a beginning of the charging operation.

20. The method according to claim 19, wherein obtaining, via the camera system arranged on the vehicle, at least one image of the charging unit further comprises obtaining, via the camera system, at least one image of the charging unit when the vehicle is in the charging position during the charging operation.