WO2014103795A1

WO2014103795A1 - Contactless power supply device and contactless power supply system

Info

Publication number: WO2014103795A1
Application number: PCT/JP2013/083742
Authority: WO
Inventors: 成幸吉田; 吉本　貫太郎; 木下　拓哉
Original assignee: 日産自動車株式会社
Priority date: 2012-12-26
Filing date: 2013-12-17
Publication date: 2014-07-03
Also published as: JP2016034169A

Abstract

In the present invention, a contactless power supply device is provided with the following: a lower coil disposed on a lower side when a power transmitting coil and a power receiving coil are facing each other; a housing for accommodating the lower coil; a coil sensor for outputting a signal in accordance with magnetic field changes brought about by the adherence of foreign matter to a projection portion of a position, of the upper surface of the housing, at which at least the lower coil is accommodated; an optical sensor that outputs one signal of either a signal indicating that light is emitted along the upper surface of the housing and at a prescribed distance above the upper surface that includes the projection portion and in which light is received, or a signal indicating that light is blocked by the intrusion of foreign matter at a prescribed distance above the upper surface; and a foreign matter detection means for detecting foreign matter on the basis of the signals from the coil sensor and the optical sensor.

Description

Non-contact power supply device and non-contact power supply system

The present invention relates to a contactless power supply device and a contactless power supply system.

Conventionally, a non-contact power feeding device that charges a vehicle battery such as an electric vehicle in a non-contact manner by magnetic coupling between a power transmission coil provided on the ground and a power reception coil provided on the vehicle has been proposed. In addition, a non-contact power feeding device is also proposed that detects foreign matter between coils because foreign matter is interposed between the power transmission coil and the power receiving coil, which affects power transmission efficiency and safety. Has been. In such a non-contact power feeding device, for example, a parameter in a state in which no foreign matter is present is created, and when this parameter changes, it is determined that a foreign matter has entered. A related non-contact power feeding apparatus is, for example, Japanese Patent Publication No. 2010-252498 (Patent Document 1).

However, in the non-contact power supply device described in Patent Document 1, when the non-contact power supply is performed at a relatively large distance, the parameters are easily changed depending on the power transmission state, the ambient temperature, and the like. If the parameters are not adjusted according to the above, accurate foreign object detection cannot be performed. For this reason, in the non-contact power supply device described in Patent Document 1, it is difficult to perform non-contact power supply at a relatively large distance.

The present invention has been made to solve such a conventional problem, and according to the present invention, a non-contact power feeding apparatus and a non-contact power feeding apparatus capable of accurately detecting a foreign object while improving the non-contact power feeding distance. A contact power supply system can be provided.

According to the technical aspect of the present invention, the non-contact power feeding device includes a housing that houses a lower coil that is disposed on the lower side when the power transmission coil and the power receiving coil face each other, and an upper surface of the housing. A coil sensor that outputs a signal in accordance with a magnetic field change caused by a foreign matter adhering thereto, an optical sensor that outputs a signal indicating that light has been blocked by the entry of the foreign matter above a predetermined distance above the upper surface of the housing, a coil sensor, Foreign matter detecting means for detecting foreign matter based on a signal from the optical sensor.

According to another technical aspect of the present invention, the power transmission coil and the power receiving coil are vertically opposed to each other, and the power is transmitted from the power transmitting coil to the power receiving coil in a non-contact manner by magnetic coupling between the two coils. The apparatus control method detects a magnetic field change caused by a foreign matter adhering to a projected portion of a location where a lower coil disposed on the lower side of the upper surface of the housing is accommodated when the coils are opposed to each other. When the first detection signal is output, the presence of a foreign object is determined based on the first detection signal, and the presence of the foreign object is not determined based on the first detection signal. In this case, a predetermined optical path is provided above a predetermined distance above the upper surface including the projection portion, and a second detection signal is output as to whether or not the optical path has been blocked by entry of a foreign substance above the predetermined distance above the surface. It and, if it is determined that there is foreign matter on the basis of the second detection signal is characterized in that it comprises a notifying of the presence of foreign material.

It is a schematic block diagram of the non-contact electric power feeding system containing the non-contact electric power feeder which concerns on this embodiment. It is a partial enlarged view of the non-contact electric power feeding system shown in FIG. It is a top view which shows the detailed arrangement | positioning of the coil sensor shown in FIG. It is a perspective view which shows the detailed arrangement | positioning of the optical sensor shown in FIG. It is a flowchart which shows operation | movement of the non-contact electric power feeder which concerns on this embodiment.

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a schematic configuration diagram of a contactless power feeding system including a contactless power feeding device according to the present embodiment. As shown in FIG. 1, the non-contact power feeding system 1 according to the present embodiment includes a vehicle-side unit mounted on a vehicle 200 and a non-contact power feeding device 100 provided on the ground side. In this system, electric power is supplied from the power transmission coil 12 to the power reception coil 22 of the vehicle-side unit in a non-contact manner, and the vehicle battery 28 provided in the vehicle 200 is charged.

The non-contact power supply apparatus 100 is installed in a power supply stand, a parking lot, or the like. When the power transmission coil 12 and the power reception coil 22 are vertically opposed, power is transmitted by electromagnetic coupling between the

coils

12 and 22. Power is transmitted from the coil 12 to the power receiving coil 12 in a non-contact manner. Such a non-contact power supply apparatus 100 includes a power control unit 11, a wireless communication unit 14, and a control unit 15 in addition to the power transmission coil 12 described above.

The power control unit 11 is a circuit for converting AC power transmitted from the AC power source 300 into high-frequency AC power and transmitting the AC power to the power transmission coil 12. The rectification unit 111, a PFC (Power Factor Correction) circuit 112, The inverter 113 and the sensor 114 that detects the output current of the PFC circuit 112 are provided.

The rectifying unit 111 is a circuit that is electrically connected to the AC power supply 300 and rectifies the output AC power from the AC power supply 300. The PFC circuit 112 is a circuit for improving the power factor by shaping the output waveform (pulsating flow) from the rectifying unit 111, and is connected between the rectifying unit 111 and the inverter 113. The inverter 113 is a power conversion circuit including a PWM control circuit having a switching element such as a smoothing capacitor or IGBT, and converts DC power into high-frequency AC power based on a switching control signal from the control unit 15. The power is supplied to the power transmission coil 12. The sensor 114 is connected between the PFC circuit 112 and the inverter 113, and detects current and voltage.

The power transmission coil 12 is a coil for supplying power in a non-contact manner to the power reception coil 22 on the vehicle 200 side, and is wound in a circular shape in a direction parallel to the surface of the parking space. Such a power transmission coil 12 is housed in a housing 101 provided on the parking space, and when the vehicle 200 is parked at an appropriate parking position, the power reception coil 22 is kept at a distance from the power reception coil 22. 22 is configured to be positioned immediately below.

The wireless communication unit 14 performs bidirectional communication with the wireless communication unit 24 on the vehicle 200 side. The communication frequency between the wireless communication unit 14 and the wireless communication unit 24 is set to a frequency higher than the frequency used in the vehicle peripheral device in consideration of interference with the vehicle peripheral device such as an intelligent key. For communication between the wireless communication unit 14 and the wireless communication unit 24, a communication method suitable for a long distance such as various wireless LAN methods is used.

The control part 15 is a part which controls the non-contact electric power feeder 100 whole, and controls the electric power control part 11 and the radio | wireless communication part 14. FIG. The control unit 15 transmits a control signal for starting power supply from the non-contact power supply device 100 to the vehicle 200 side by communication between the wireless communication unit 14 and the wireless communication unit 24, or from the vehicle 200 side. A control signal indicating that power is to be received from the non-contact power supply apparatus 100 is received. The control unit 15 performs switching control of the inverter 113 based on the detection current of the sensor 114 and controls electric power transmitted from the power transmission coil 12.

In addition to the power receiving coil 22 described above, the vehicle 200 includes a wireless communication unit 24, a control unit (second foreign object detection means) 25, a rectifying unit 26, a relay unit 27, a vehicle battery 28, an inverter 29, The motor 30 and the notification part 32 are provided as a vehicle side unit.

The power reception coil 22 is a coil that receives power supply in a non-contact manner from the power transmission coil 12 of the non-contact power supply device 100, and is provided in the second casing 201 provided between the bottom surface of the vehicle 200, particularly between the rear wheels. It is stored. Similar to the power transmission coil 12, the power reception coil 22 is wound in a circular shape in a direction parallel to the surface of the parking space. When the vehicle 200 is parked at an appropriate parking position, the power receiving coil 22 is configured to be positioned immediately above the power transmission coil 12 while maintaining a distance from the power transmission coil 12.

The wireless communication unit 24 performs bidirectional communication with the wireless communication unit 14 provided on the non-contact power supply apparatus 100 side. The rectification unit 26 is connected to the power reception coil 22 and is configured by a rectification circuit that rectifies AC power received by the power reception coil 26 into direct current. The relay unit 27 includes a relay switch that is turned on and off by the control of the control unit (second foreign object detector) 25. By turning off the relay switch, the vehicle battery 28 side, the charging circuit unit side, The receiving coil 22 and the rectifying unit 26 are separated.

The vehicle battery 28 is a power source of the vehicle 200 and is configured by connecting a plurality of secondary batteries. The inverter 29 is a control circuit such as a PWM control circuit having a switching element such as an IGBT, and converts the DC power output from the vehicle battery 28 into AC power based on the switching control signal and supplies it to the motor 30. It is. The motor 30 is composed of, for example, a three-phase AC motor and serves as a drive source for driving the vehicle 200.

The control unit 25 is a controller that controls the charging of the vehicle battery 28 and the wireless communication unit 24. The control unit 25 transmits a signal indicating that charging is started to the control unit 15 of the non-contact power feeding apparatus 100 via the wireless communication unit 24 and the wireless communication unit 14. Moreover, the control part 25 is connected with the controller which controls the vehicle 200 whole which is not shown in figure by a CAN communication network. The controller manages switching control of the inverter 29 and the state of charge (SOC) of the vehicle battery 22. Furthermore, when the controller 25 reaches full charge based on the SOC of the vehicle battery 22, the controller 25 transmits a signal to the effect that charging is terminated to the controller 15 of the non-contact power feeding apparatus 100.

The notification unit 32 is a navigation display, a warning lamp, a speaker, and the like that are provided so that the driver can visually recognize, and provides various types of information to the driver based on signals from the control unit 25.

Furthermore, in the present embodiment, the coil sensor 16 and the optical sensor 17 are provided in the housing 101, and the second coil sensor 34 is provided in the second housing 201.

FIG. 2 is a partially enlarged view of the non-contact power feeding system 1 shown in FIG. As shown in FIG. 2, a power transmission coil 12 wound in a circular shape in a direction parallel to the surface of the parking space is housed in the housing 101, and the power transmission coil 12 and the upper surface of the housing 101 are A coil sensor 16 is interposed between the two.

The coil sensor 16 constitutes a sensing coil by, for example, winding a coil on the circumference of the core, and this coil is driven to be excited. The coil sensor 16 generates a magnetic field through which a magnetic path passes in the vicinity of the upper surface of the housing 101 as indicated by a broken line in FIG. As shown in FIG. 2, such a coil sensor 16 outputs a signal corresponding to a magnetic field change caused by foreign matter adhering to the upper surface of the housing 101, and in particular a projection of a place where the power transmission coil 12 is housed. A signal (first detection signal) corresponding to a change in the magnetic field generated by the foreign matter adhering to the portion is output.

FIG. 3 is a top view showing a detailed arrangement of the coil sensor 16 shown in FIG. As shown in FIG. 3, a plurality of coil sensors 16 are arranged in a matrix so as to cover the projected portion P of the power transmission coil 12. Thereby, the signal according to the magnetic field change produced by the foreign material adhering to the projection part P of the power transmission coil 12 is output. Note that the coil sensor 16 may be provided so as to output at least a signal corresponding to a magnetic field change caused by a foreign matter adhering to the projection portion P, and may be provided so as to include the outside of the projection portion P.

Refer to FIG. 2 again. The optical sensor 17 is a detector that detects the blocking of the optical path by a foreign substance, and is provided on the upper surface side of the housing 101. The light emitting unit 17a that emits light (for example, infrared rays) and the light receiving unit that receives light from the light emitting unit 17a. Part (photodetector) 17b. Light from the light emitting unit 17 a is emitted so as to pass a predetermined distance above the upper surface along the upper surface of the housing 101.

FIG. 4 is a perspective view showing a detailed arrangement of the optical sensor 17 shown in FIG. As shown in FIG. 4, the optical sensor 17 includes a plurality of light emitting units 17a and a plurality of light receiving units 17b. Light from the plurality of light emitting portions 17 a is emitted so that the optical path covers the projection portion P along the upper surface of the housing 101. The plurality of light receiving units 17b receive light from each of the plurality of light emitting units 17a. On the other hand, when light is blocked by the intrusion of foreign matter, the plurality of light receiving units 17b reduce the amount of light received from each of the plurality of light emitting units 17a.

In this embodiment, the optical sensor 17 indicates that the light from the light emitting unit 17a has been received for each of the plurality of light receiving units 17b, and that the light has been blocked by the intrusion of foreign matter a predetermined distance above the surface. Any one of the signals (second detection signal) is output. Therefore, it is output as the second detection signal whether or not the optical path provided above the upper surface including the projection portion P by a predetermined distance is blocked by the entry of foreign matter.

Refer to FIG. 2 again. As shown in FIG. 2, a power receiving coil 22 wound in a circular shape in a direction parallel to the surface of the parking space is housed in the second housing 201, and the power receiving coil 22 and the second housing 201 are accommodated. A second coil sensor 34 is interposed between the lower surface and the lower surface. The second coil sensor 34 has the same configuration as that of the coil sensor 16 and outputs a signal corresponding to a change in the magnetic field generated around the coil. The vehicle 200 is provided with a cover 202 that covers the lower side of the second housing 201. When the lower side of the second casing 201 is covered with the cover 202 as in the present embodiment, it is assumed that the cover 202 is also a part of the second casing 201.

As shown in FIG. 2, the second coil sensor 34 outputs a signal corresponding to a magnetic field change caused by foreign matter adhering to the lower surface of the cover 202. In particular, the second coil sensor 34 accommodates the power receiving coil 22. A signal corresponding to the change in the magnetic field caused by the foreign matter adhering to the projected portion P at the location is output. In addition, a plurality of the second coil sensors 34 are arranged in a matrix so as to cover the projection portion P of the power receiving coil 22, but as long as at least foreign matter attached to the projection portion P is detected. Alternatively, it may be provided so as to include the outside of the projection portion P.

Refer to Fig. 1 again. As shown in FIG. 1, the control unit 15 includes a foreign matter detection unit (foreign matter detection unit) 15a and a power supply control unit (power supply control unit) 15b. The foreign object detection unit 15 a detects a foreign object based on signals from the coil sensor 16 and the optical sensor 17. Specifically, when detecting a change in the magnetic field based on a signal from the coil sensor 16, the foreign object detection unit 15 a determines that a foreign object has adhered to a location where the coil sensor 16 is installed. Further, when it is determined that the light is blocked by the signal from the optical sensor 17, the foreign object detection unit 15a detects that there is a foreign object at the blocked position.

In the present embodiment, the coil sensor 16 and the optical sensor 17 are preferably configured such that the timing of the detection operation is shifted. For example, the coil sensor 16 has a foreign object attached to the upper surface of the housing 101 as a detection target, and the optical sensor 17 has a foreign object slightly above the surface as a detection target. Therefore, first, the coil sensor 16 starts a foreign object detection operation (that is, an operation for exciting and driving the coil) prior to the foreign object detection operation (that is, the light emission operation) by the optical sensor 17. The foreign matter detection operation is started after the end of the foreign matter detection operation by the coil sensor 16. As a result, if no foreign matter on the surface is detected by the coil sensor 16, it is possible to detect the entry of foreign matter from the outside if the foreign matter is detected by the optical sensor 17 without detecting the foreign matter on the surface thereafter. This is because foreign matters can be detected efficiently.

The power supply control unit 15 b performs a non-contact power supply process from the power transmission coil 12 to the power reception coil 22. That is, after the vehicle 200 is parked at an appropriate position, the power supply control unit 15b controls the power control unit 11 to apply high-frequency power to the power transmission coil 12 and perform a process for performing non-contact power supply. . In addition, the power supply control unit 15b starts executing the power supply process after the end of the foreign object detection operation by the coil sensor 16 and before the start of the foreign object detection operation by the optical sensor 17. As a result, it is possible to prevent the foreign matter detection operation of the coil sensor 16 from being affected during power feeding, and to detect foreign matter intrusion by the optical sensor 17 during power feeding.

Furthermore, as shown in FIG. 1, the controller 25 on the vehicle 200 side also detects foreign matter based on the signal from the second coil sensor 34. Thereby, the case where mud etc. have adhered to the lower surface of the cover 202 by the mud splash etc. of the vehicle 200 is detectable.

Next, an example of a power feeding method of the contactless power feeding device 100 according to the present embodiment will be described. First, it is assumed that the vehicle 200 approaches the non-contact power feeding device 100. Whether or not the vehicle is approaching is determined based on GPS information, map information, and the like.

Next, the control unit 25 of the vehicle 200 activates the wireless communication unit 24 so that it can communicate with the wireless communication unit 14 of the non-contact power supply apparatus 100. When communication is possible between the wireless communication unit 14 and the wireless communication unit 24, the control unit 25 of the vehicle 200 transmits a signal for establishing a link from the wireless communication unit 24 to the wireless communication unit 14. And the control part 15 of the non-contact electric power feeder 100 sends back the signal to the effect that the said signal was received from the wireless communication part 14 to the wireless communication part 24. Thereby, a link is established between the wireless communication unit 14 and the wireless communication unit 24.

In addition, the control unit 25 of the vehicle 200 transmits the ID (identification information) of the vehicle 200 to the control unit 15 of the non-contact power feeding apparatus 100 through communication between the wireless communication unit 14 and the wireless communication unit 24. The control unit 15 of the contactless power supply device 100 performs ID authentication by determining whether or not the ID transmitted from the vehicle 200 side matches the ID registered in advance. In the contactless power supply system 1 according to the present embodiment, the ID of the vehicle 200 that can be supplied with power is registered in the contactless power supply apparatus 100 in advance. For this reason, only the vehicle 200 that matches the registered ID can be powered by the above ID authentication. However, the non-contact power feeding system 1 is not limited to this, and may be without ID authentication.

After completion of ID authentication, the control unit 15 determines whether or not the vehicle 200 has reached an appropriate position. When the vehicle 200 is not in an appropriate position, the control unit 15 transmits guidance information for guiding the vehicle 200 through the wireless communication unit 14. Thereby, the control unit 25 on the vehicle 200 side displays guidance information on the notification unit 32 and indicates the direction in which the vehicle 200 is moved to the driver. On the other hand, when the vehicle 200 reaches an appropriate position, the control unit 15 controls the power control unit 11 to apply high-frequency power to the power transmission coil 12. Thereby, electric power feeding is performed in a non-contact manner.

In addition, before the above power feeding, the coil sensor 16 and the second coil sensor 34 start a foreign object detection operation, and output a signal corresponding to a magnetic field change to the

control units

15 and 25. Thereby, the foreign object detection unit 15a detects the foreign object on the upper surface of the casing 101, and also detects the foreign object on the lower surface of the second casing 201 for the control unit 25.

Then, power supply is started after the end of the foreign object detection, and the foreign object detection operation by the optical sensor 17 is started. Accordingly, a signal indicating that light is received from the light emitting unit 17a or that light cannot be received is output from each of the light receiving units 17b of the optical sensor 17, and the foreign matter detection unit 15a detects the foreign matter based on this signal. It becomes. The foreign object detection operation by the optical sensor 17 may be performed, for example, until charging is completed, or may be terminated after being continuously performed for a predetermined time.

In the above, the optical sensor 17 may start the detection operation simultaneously with the end of the detection operation of the coil sensor 16. The coil sensor 16 may end the detection operation simultaneously with the start of power supply, and the optical sensor 17 may start the detection operation simultaneously with the start of power supply. That is, the timings do not have to be clearly shifted and may be simultaneous.

Next, the operation of the non-contact power feeding apparatus 100 according to this embodiment will be described. FIG. 5 is a flowchart showing the operation of the non-contact power feeding apparatus 100 according to this embodiment. As shown in FIG. 5, first, the control unit 15 of the non-contact power feeding apparatus 100 determines whether or not parking is started (S1). In this process, the control unit 15 determines whether parking is started based on, for example, whether a link with the vehicle 200 is established. Note that the method for determining whether or not parking has started is not limited to this.

When it is determined that parking is not started (S1: NO), this process is repeated until it is determined that parking is started. On the other hand, when it is determined that parking is started (S1: YES), the coil sensor 16 starts a detection operation (S2). In this process, the control unit 15 may also start the detection operation for the second coil sensor 34 by transmitting information to the vehicle 200 via the wireless communication unit 14.

Thereafter, the foreign object detector 15a determines whether or not there is a foreign object based on a signal from the coil sensor 16 (S3). When it is determined that there is a foreign object (S3: YES), the control unit 15 is notified to the vehicle 200 side via the wireless communication unit 14 (S4). As a result, the control unit 25 of the vehicle 200 displays the fact on the notification unit 32 and prompts the driver to remove the foreign matter. Then, the process proceeds to step S3.

On the other hand, when it is determined that no foreign matter exists (S3: NO), the control unit 15 determines whether or not parking is completed (S5). The second housing 201 is provided with a transmitting antenna (not shown) that transmits electromagnetic waves, and the housing 101 is provided with a plurality of receiving antennas (not shown) that output signals according to the received electromagnetic wave intensity. ing. Whether or not parking is completed is determined based on signals from a plurality of receiving antennas.

If it is determined that parking has not been completed (S5: NO), the process proceeds to step S3. On the other hand, when it is determined that the parking is completed (S5: YES), the coil sensor 16 ends the detection operation (S6). And the electric power feeding control part 15b performs an electric power feeding process (S7). Thereby, high frequency power is applied to the power transmission coil 12.

Thereafter, the optical sensor 17 starts a detection operation (S8). And the foreign material detection part 15a judges whether the foreign material invaded based on the signal from the optical sensor 17 (S9). When it is determined that no foreign matter has entered (S9: NO), the charging control unit 15b determines whether or not charging is completed (S10). In this process, the charging control unit 15b determines whether or not the charging is completed based on whether or not information indicating that the target charging amount is obtained from the vehicle 200 side, for example.

If it is determined that charging has not been completed (S10: NO), the process proceeds to step S9. On the other hand, when it is determined that the charging is completed (S10: YES), the power supply control unit 15b stops the power supply (S11), and the optical sensor 17 ends the detection operation (S12). Then, the process shown in FIG. 5 ends.

By the way, when it is determined that a foreign object has entered (S9: YES), the control unit 15 notifies the vehicle 200 side via the wireless communication unit 14 (S13). As a result, the control unit 25 of the vehicle 200 displays the fact on the notification unit 32 and prompts the driver to remove the foreign matter. And a process transfers to step S11, the electric power feeding control part 15b stops electric power feeding (S11), and the optical sensor 17 complete | finishes a detection operation (S12). Then, the process shown in FIG. 5 ends.

As described above, according to the contactless power supply device 100 according to the present embodiment, the foreign matter of the power transmission coil projection portion P in the upper surface of the housing 101 is detected by the coil sensor 16 and from the upper surface of the housing 101. The light sensor 17 detects a foreign matter on the projection portion P located above a predetermined distance. For this reason, a foreign object having a slight thickness can be detected by the optical sensor 17 that detects a foreign object a predetermined distance above the upper surface of the casing 101, and a foreign object such as a thin coin can be detected by the coil sensor 16. Foreign matter on the upper surface can be accurately detected. In particular, the coil sensor 16 only needs to be able to detect a thin foreign object on the upper surface of the housing, and the optical sensor 17 is not affected by the power transmission state, the temperature environment, and the like. Will not decline. Accordingly, it is possible to accurately detect foreign matters while improving the non-contact power feeding distance.

The coil sensor 16 starts the foreign object detection operation prior to the foreign object detection operation by the optical sensor 17, and the optical sensor 17 starts the foreign object detection operation after the end of the foreign object detection operation by the coil sensor 16. Therefore, after the foreign substance on the upper surface of the housing is detected by the coil sensor 16 and it is confirmed that there is no foreign substance on the surface, the foreign substance entering from the outside can be detected by the optical sensor 17. As described above, when the foreign matter on the surface is not detected, it is sufficient to detect the foreign matter from the outside by the optical sensor 17 without detecting the foreign matter on the surface thereafter, and the foreign matter can be detected efficiently.

Further, since the power supply process is started after the end of the foreign object detection operation by the coil sensor 16 and before the start of the foreign object detection operation by the optical sensor 17, the foreign object detection by the coil sensor 16 is performed at the time of power supply. In addition, it is possible to prevent a situation where the foreign object detection of the coil sensor 16 is affected by the power supply, and it is possible to detect the entry of the foreign substance by the optical sensor 17 during the power supply.

Further, according to the non-contact power feeding system 1 according to the present embodiment, the foreign matter of the power receiving coil projection portion P in the lower surface of the cover 202 is detected by the second coil sensor 34. Thus, it is possible to detect a case where mud or the like has adhered to the lower surface of the cover 202.

As mentioned above, although this invention was demonstrated based on embodiment, this invention is not limited to the said embodiment, You may add in the range which does not deviate from the meaning of this invention.

For example, in this embodiment, the coil sensor 16 outputs a signal corresponding to the change in the magnetic field, and the foreign object detection unit 15a determines whether or not the foreign object is detected. However, the present invention is not limited to this, and the coil sensor 16 may detect a foreign object according to a change in the magnetic field and transmit the detection result to the control unit 15. In this case, the foreign matter detection means is built in the coil sensor 16.

Similarly, the optical sensor 17 may be configured to detect a foreign object from the light receiving state and transmit the detection result to the control unit 15. In this case also, the foreign matter detection means is built in the optical sensor 17.

Further, the second coil sensor 34 may similarly detect a foreign object according to a change in the magnetic field and transmit the detection result to the control unit 25. In this case, the second foreign matter detection means is built in the second coil sensor 34.

In addition, the coil sensor 16 and the second coil sensor 34 according to the present embodiment are exemplified as those that may be affected during power feeding and may not be accurately detected. However, the present invention is not limited to this, and some coil sensors are not affected during power feeding, and such coil sensors may be used.

Furthermore, in this embodiment, a cover 202 that covers the lower side of the second casing 201 is provided. Thus, in the present invention, the case includes not only a single case but also a concept including such a cover. Therefore, the housing 101 may also be provided with a cover. In this case, it is needless to say that the coil sensor 16 detects foreign matter on the cover surface and the optical sensor detects foreign matter a predetermined distance above the cover surface.

According to the present invention, the foreign matter having a slight thickness can be detected by the optical sensor that detects the foreign matter above a predetermined distance from the upper surface of the housing, and the foreign matter such as a thin coin can be detected by the coil sensor. Foreign matter on the upper surface can be accurately detected. In particular, the coil sensor only needs to be able to detect a thin foreign object on the upper surface of the housing, and the optical sensor is not affected by the power transmission state, temperature environment, etc., so even if the non-contact power feeding distance is increased, the detection accuracy decreases. There is nothing to do. Accordingly, it is possible to accurately detect foreign matters while improving the non-contact power feeding distance.

(US designation)
This international patent application is related to designation in the United States of Japan. Patent application No. 2012-283349, filed on Dec. 26, 2012, which incorporates the benefit of priority under United States Patent Act 119 (a) and discloses the disclosure. Cite the contents.

Claims

A non-contact power feeding device for transmitting power in a non-contact manner from the power transmission coil to the power receiving coil by magnetic coupling of both coils, with the power transmitting coil and the power receiving coil facing up and down,
A lower coil disposed on the lower side when the two coils face each other;
A housing for housing the lower coil;
A coil sensor that outputs a signal in accordance with a magnetic field change caused by a foreign matter adhering to at least a projection portion where the lower coil is housed in the upper surface of the housing;
A light emitting unit that emits light above the upper surface including the projection portion along the upper surface of the housing, and a light receiving unit that receives the light emitted from the light emitting unit; An optical sensor that outputs either one of a signal indicating that the light from the light emitting unit has been received by the unit and a signal indicating that the light has been blocked by entry of a foreign substance above a predetermined distance on the surface;
Foreign matter detection means for detecting foreign matter based on signals from the coil sensor and the optical sensor;
A non-contact power feeding device comprising:
The coil sensor starts the foreign object detection operation prior to the foreign object detection operation by the optical sensor,
The contactless power supply device according to claim 1, wherein the optical sensor starts a foreign object detection operation after the end of the foreign object detection operation by the coil sensor.
A power supply control means for performing non-contact power supply processing from the power transmission coil to the power reception coil;
The power supply control unit starts execution of power supply processing after the end of the foreign object detection operation by the coil sensor and before the start of the foreign object detection operation by the optical sensor. The non-contact electric power feeder of description.
The non-contact power feeding device according to any one of claims 1 to 3,
An upper coil disposed on the upper side when the two coils face each other;
A second housing that houses the upper coil;
A second coil sensor that outputs a signal in accordance with a magnetic field change caused by a foreign matter adhering to at least a projection portion where the upper coil is housed on the lower surface of the second housing;
Second foreign matter detection means for detecting foreign matter based on a signal from the second coil sensor;
A non-contact power feeding system comprising:
A control method for a non-contact power feeding device that causes a power transmitting coil and a power receiving coil to face each other up and down, and transmits power from the power transmitting coil to the power receiving coil in a non-contact manner by magnetic coupling of both coils,
A first detection signal is output by detecting a magnetic field change caused by a foreign matter adhering to a projection portion of a location where a lower coil disposed on the lower side of the upper surface of the casing is accommodated when the two coils face each other. To do
Notifying the presence of a foreign object when it is determined that there is a foreign object based on the first detection signal;
If it is not determined that there is a foreign substance based on the first detection signal, a predetermined optical path is provided above a predetermined distance above the upper surface including the projection portion, and the optical path is blocked by the entry of the foreign substance above the predetermined distance on the surface. Outputting a second detection signal as to whether or not (S8),
Notifying the presence of a foreign object when it is determined that there is a foreign object based on the second detection signal;
A control method for a non-contact power feeding device.