Foreign matter sensing device and non-contact electric-power transfer system

• US 9,080,988 B2
• Filed: 03/14/2013
• Issued: 07/14/2015
• Est. Priority Date: 03/15/2012
• Status: Active Grant

• Current Assignee: DENSO Corporation
• Original Assignee: DENSO Corporation
• Inventors: Honda, Takayoshi, Okada, Hiroki
• Primary Examiner(s): Berhanu, Samuel
• Assistant Examiner(s): Robbins, Jerry D
• Application Number:
  US13/826,151
• Publication Number:
  US 20130241476A1
• Time in Patent Office: 852 Days
• Field of Search: 320/108
• US Class Current: 1/1
• 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 50/40 using propulsion power supplied by capacitors
• CPC Class Codes: B60L 50/66 Arrangements of batteries
• 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 53/36 by positioning the vehicle
• CPC Class Codes: B60L 53/37 using optical position determination, e.g. using cameras
• CPC Class Codes: B60L 58/21 having the same nominal voltage
• CPC Class Codes: G01N 21/94 Investigating contamination, e.g. dust G01N21/85 takes precedence
• CPC Class Codes: H02J 50/10 using inductive coupling
• 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: 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 7/00034 Charger exchanging data with an electronic device, i.e. telephone, whose internal battery is under charge
• 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 foreign matter sensing device includes a first determiner that determines whether there is a foreign matter in a foreign matter detection range based on an image imaged by an imaging portion, and a second determiner that determines whether there is a foreign matter in the foreign matter detection range based on a temperature sensed by a temperature sensor. The second determiner executes determining whether there is a foreign matter in the foreign matter detection range while electric-power is transferred between a vehicle-side coil and an out-of-vehicle coil, when the first determiner determines that there is no foreign matter after the imaging portion images the image of the foreign matter detection range in response to a start demand instructing to start transferring electric-power.

Claims

1. A foreign matter sensing device that detects a foreign matter between a vehicle-side coil, which is used when a battery equipment mounted to a vehicle is charged and discharged, and an out-of-vehicle coil which performs a non-contact electric-power transfer with the vehicle-side coil, the foreign matter sensing device comprising:

an imaging portion that imaging an image of a foreign matter detection range above the out-of-vehicle coil;

a first determiner that determines whether there is a foreign matter in the foreign matter detection range based on the image imaged by the imaging portion;

a temperature sensor sensing a temperature of the foreign matter detection range; and

a second determiner that determines whether there is a foreign matter in the foreign matter detection range based on the temperature sensed by the temperature sensor, wherein

the first determiner determines whether there is a foreign matter in the foreign matter detection range in response to a start demand instructing to start transferring electric-power,

the second determiner executes determining whether there is a foreign matter in the foreign matter detection range while electric-power is transferred between the vehicle-side coil and the out-of-vehicle coil, after the first determiner determines that there is no foreign matter;

the second determiner determines whether there is a foreign matter in the foreign matter detection range by comparing the temperature sensed by the temperature sensor with a prediction temperature of the foreign matter detection range assumed while the non-contact electric-power transfer is performed;

the foreign matter sensing device further comprises;

a position displacement measuring portion that measures a position displacement of the out-of-vehicle coil from a reference position based on the image imaged by the imaging portion, the reference position being defined by a relative position of the out-of-vehicle coil relative to the vehicle-side coil at which a power transmission efficiency of the non-contact electric-power transfer becomes the maximum; and

a first correction portion that corrects the prediction temperature based on the position displacement of the out-of-vehicle coil measured by the position displacement measuring portion.

2. The foreign matter sensing device according to claim 1, wherein

the foreign matter detection range is divided into a plurality of detection areas,

the temperature sensor senses temperature in at least two detection areas of the plurality of detection areas, and

the second determiner determines whether there is a foreign matter based on the temperature in the at least two detection areas.

3. The foreign matter sensing device according to claim 1, wherein

the foreign matter detection range is larger than a range of a road surface overlapping with the vehicle-side coil.

4. The foreign matter sensing device according to claim 1, wherein

at least two of the vehicle-side coils are arranged along a road surface direction, and at least two of the out-of-vehicle coils are arranged along the road surface direction, and

the foreign matter detection range is set to include the at least two of the out-of-vehicle coils that transfer electric-power with the vehicle-side coils.

5. The foreign matter sensing device according to claim 1, wherein

the second determiner determines that there is a foreign matter when a variation amount of the temperature sensed by the temperature sensor is larger than or equal to a variation threshold value at which the foreign matter is assumed to generate heat.

6. The foreign matter sensing device according to claim 1, further comprising:

at least two distance measuring portions that measure a distance between the vehicle-side coil and the out-of-vehicle coil; and

an inclination measuring portion that measures an inclination of the out-of-vehicle coil relative to the vehicle-side coil based on the distance measured by the at least two distance measuring portions, wherein

the first correction portion corrects the prediction temperature based on the position displacement of the out-of-vehicle coil measured by the position displacement measuring portion and the inclination of the out-of-vehicle coil measured by the inclination measuring portion.

7. The foreign matter sensing device according to claim 1, wherein

the foreign matter detection range has a positional information indicating part that indicates a positional information for determining a relative position of the out-of-vehicle coil relative to the foreign matter detection range.

8. The foreign matter sensing device according to claim 7, wherein

the positional information indicating part is a luminous paint applied to an overlap range of the out-of-vehicle coil overlapping with the foreign matter detection range.

9. The foreign matter sensing device according to claim 7, wherein

the positional information indicating part is an optically-readable information code relating to the relative position of the out-of-vehicle coil relative to the foreign matter detection range.

10. The foreign matter sensing device according to claim 7, wherein

the positional information indicating part is defined by forming an overlap range of the out-of-vehicle coil overlapping with the foreign matter detection range into a convex or concave shape relative to a surrounding range surrounding the overlap range.

11. The foreign matter sensing device according to claim 1, further comprising:

an outside air temperature sensor sensing a temperature of outside air;

wherein

the correction portion corrects the prediction temperature based on the temperature of outside air sensed by the outside air temperature sensor.

12. The foreign matter sensing device according to claim 1, wherein:

the correction portion corrects the prediction temperature in accordance with an electric-power transfer amount while the non-contact electric-power transfer is performed.

13. The foreign matter sensing device according to claim 1, further comprising:

an alarming portion which reports an alarm information informing a presence of the foreign matter when the first determiner or the second determiner determines that there is the foreign matter.

14. The foreign matter sensing device according to claim 13, wherein

the imaging portion images the foreign matter detection range as a foreign matter detection image, when it is determined that there is the foreign matter, and

the alarm information includes the foreign matter detection image.

15. The foreign matter sensing device according to claim 1, wherein the imaging portion images the foreign matter detection range as a foreign matter detection image when it is determined that there is the foreign matter, the foreign matter sensing device further comprising:

a third determiner that determines whether there is a foreign matter in the foreign matter detection range based on the foreign matter detection image imaged by the imaging portion.

16. The foreign matter sensing device according to claim 1, wherein the imaging portion intermittently images the foreign matter detection range as an intermittent image, the foreign matter sensing device further comprising:

a third determiner that determines whether there is a foreign matter in the foreign matter detection range based on the intermittent image imaged by the imaging portion.

17. The foreign matter sensing device according to claim 1, further comprising:

a lighting portion that emits a light to the foreign matter detection range.

18. The foreign matter sensing device according to claim 1, wherein

the temperature sensor is an infrared sensor which senses the temperature of the foreign matter detection range by detecting an infrared light from the foreign matter detection range.

19. The foreign matter sensing device according to claim 18, wherein

the infrared sensor is one of a plurality of infrared sensors.

20. A non-contact electric-power transfer system comprising:

the foreign matter sensing device according to claim 1;

the out-of-vehicle coil; and

a control part that controls the non-contact electric-power transfer using the battery equipment through the out-of-vehicle coil and the vehicle-side coil.

21. The non-contact electric-power transfer system according to claim 20, wherein

the control part stops the non-contact electric-power transfer when the foreign matter sensing device detects a foreign matter.

22. The foreign matter sensing device according to claim 1, wherein

the second determiner determines whether there is a foreign matter in the foreign matter detection range based on the temperature sensed by the temperature sensor without lighting a space between the out-of-vehicle coil and the vehicle-side coil only after the first determiner finishes determining that there is no foreign matter in the foreign matter detection range.

23. A foreign matter sensing device configured to detect a foreign matter between a vehicle-side coil, which is used when a battery equipment mounted to a vehicle is charged and discharged, and an out-of-vehicle coil which performs a non-contact electric-power transfer with the vehicle-side coil, the foreign matter sensing device comprising:

a control unit, including a microcomputer and storage memory, the control unit configured to;

receive image data corresponding to an image of a foreign matter detection range proximate to the out-of-vehicle coil;

conduct a first determination of whether there is foreign matter in the foreign matter detection range based on the received image data in response to a start command instructing to start transfer of electric-power;

receive temperature data corresponding to a temperature of the foreign matter detection range;

conduct a second determination of whether there is foreign matter in the foreign matter detection range based on received temperature data while electric-power is transferred between the vehicle-side coil and the out-of-vehicle coil and after the first determination determines that there is no foreign matter in the foreign matter detection range;

wherein the second determination determines whether there is a foreign matter in the foreign matter detection range by comparing the temperature corresponding to the received temperature data with a prediction temperature of the foreign matter detection range assumed while the non-contact electric-power transfer is performed;

measure a position displacement of the out-of-vehicle coil from a reference position based on the image corresponding to the received image data, the reference position being defined by a relative position of the out-of-vehicle coil relative to the vehicle-side coil at which a power transmission efficiency of the non-contact electric-power transfer becomes the maximum; and

correct the prediction temperature based on the measured position displacement of the out-of-vehicle coil.