WO2013061617A1

WO2013061617A1 - Contactless electrical power transmission device, and electricity supply device and electricity reception device using same

Info

Publication number: WO2013061617A1
Application number: PCT/JP2012/006932
Authority: WO
Inventors: 柏本　隆; 芳弘阪本; 大森　義治; 秀樹定方; 裕明栗原; 藤田　篤志
Original assignee: パナソニック株式会社
Priority date: 2011-10-28
Filing date: 2012-10-29
Publication date: 2013-05-02
Also published as: JP2015008551A

Abstract

A contactless electrical power transmission device transmits electrical power between an electricity supply device (2) and an electricity reception device (4) using electromagnetic conduction. The electricity supply device (2) is provided with a main body, a primary coil (44), positioned between the main body and the electricity reception device (4), for generating magnetic flux, and a cover, mounted on the main body, for covering the outer side of the primary coil (44). Furthermore, the contactless electrical power transmission device is provided with an electrostatic capacity sensor (14) for detecting contamination around the cover and a monitoring part (17) for monitoring a signal detected by the electrostatic capacity sensor (14).

Description

Non-contact power transmission device, and power feeding device and power receiving device used therefor

The present invention relates to a contactless power transmission device suitable for contactless power transmission, and more particularly to a contactless power transmission device used for charging an electric propulsion vehicle such as an electric vehicle or a plug-in hybrid vehicle.

FIG. 8 is a diagram showing the configuration of the non-contact power transmission device and the periphery of the device disclosed in Patent Document 1. In FIG. 8, the non-contact power transmission device 101 includes a power feeding device (primary side) F connected to a power panel of a ground-side power source 104, and a power receiving device (secondary side) G mounted on an electric vehicle or train. It has. And at the time of electric power feeding, the electric power feeder F and the receiving device G are arrange | positioned so as to oppose through the air gap which is a space | gap space, without physical connection.

In such an arrangement state, when an alternating current is applied to the primary coil 102 provided in the power feeding device F and a magnetic flux is formed, an induced electromotive force is generated in the secondary coil 103 provided in the power receiving device G. Thereby, electric power is transmitted from the primary coil 102 to the secondary coil 103 in a non-contact manner.

The power receiving device G is connected to, for example, the in-vehicle battery 105, and the electric power transmitted from the power feeding device F to the power receiving device G is charged in the in-vehicle battery 105. The in-vehicle motor 106 is driven by the electric power stored in the in-vehicle battery 105. Note that the wireless communication device 107 performs necessary information exchange between the power feeding device F and the power receiving device G during processing related to contactless power feeding.

FIG. 9 is a cross-sectional view of the power feeding device F (power receiving device G) of FIG. FIG. 9A is a plan cross-sectional view of the power feeding device F (power receiving device G), and FIG. 9B is a side cross-sectional view of the power feeding device F (power receiving device G).

As shown in FIG. 9, the power feeding device F includes a primary coil 102, a primary magnetic core 108, a back plate 110, and a cover 111. The power receiving device G includes a secondary coil 103, a secondary magnetic core 109, a back plate 110, and a cover 111. The surfaces of the primary coil 102 and the primary magnetic core 108 of the power feeding device F and the surfaces of the secondary coil 103 and the secondary magnetic core 109 of the power receiving device G are covered and fixed by the mold resin 112 mixed with the foam material 113. ing. That is, the mold resin 112 is filled between the back plate 110 and the cover 111 of the power feeding device F (power receiving device G), and the primary coil 102 (secondary coil 103) and the primary magnetic core 108 (secondary magnetic core) inside. The surface of the core 109) is fixedly covered with a mold resin 112. The mold resin 112 is made of, for example, silicon resin, and is fixed as described above, thereby fixing the position of the primary coil 102 (secondary coil 103), ensuring its mechanical strength and exhibiting a heat dissipation function. To do. That is, in the primary coil 102 (secondary coil 103), an exciting current flows and heat is generated by Joule heat, but is radiated and cooled by heat conduction of the mold resin 112.

JP 2008-87733 A

When applying a non-contact power transmission device for charging an electric propulsion vehicle or the like, it is assumed that the power feeding device and the power receiving device are installed outdoors. Therefore, there is a possibility that foreign matter enters from between the power feeding device and the power receiving device of the non-contact power transmission device. In particular, when a metal foreign object, which is an example of a foreign object, enters between the power supply device and the power receiving device during power transmission and is placed on the cover of the power supply device or the power receiving device, leave this metal foreign object as it is. Otherwise, the metal foreign object is overheated by the eddy current generated by the magnetic flux. When the metal foreign matter that has entered in this manner is overheated and excessively heated, damage to the power feeding device and the power receiving device may occur. In addition, when a loop-shaped conductor capable of interlinking magnetic flux is inserted between the primary coil and the secondary coil, an electromotive force is generated at both ends of the conductor. Therefore, when a foreign object enters between the power feeding device (primary coil) and the power receiving device (secondary coil) during power transmission, it is required to reliably detect the entry of the foreign material.

For this reason, in the non-contact power transmission device, a sensor for detecting a foreign matter that has entered between the power feeding device and the power receiving device is provided. For example, a temperature sensor for detecting overheating of a metal foreign object is used. However, when an abnormality such as a failure occurs in the sensor that detects foreign matter, it is not possible to detect overheating of the foreign matter that has entered.

In view of the above problems, the present invention can reliably detect the intrusion of foreign matter around the cover of the power supply device or the power reception device, particularly between the power supply device (primary coil) and the power reception device (secondary coil). An object of the present invention is to provide a non-contact power transmission device.

In the first aspect of the present invention, the non-contact power transmission device performs power transmission using electromagnetic induction between the power feeding device and the power receiving device. The power supply apparatus includes a base, a primary coil that is provided on the base and generates magnetic flux, and a cover that is attached to the base and covers the primary coil. Furthermore, the non-contact power transmission device includes a capacitance sensor that detects foreign matter around the cover, and a monitoring unit that monitors a signal detected by the capacitance sensor.

According to the first aspect, the non-contact power transmission device includes a capacitance sensor that detects foreign matter around the cover and a monitoring unit that monitors a signal detected by the capacitance sensor. It is possible to operate the capacitance sensor before starting the power feeding operation by the power feeding device, and to check the normal operation of the capacitance sensor by the monitoring unit. Thereby, it can prevent that the electric power feeding operation | movement by a electric power feeder is started with an electrostatic capacitance sensor in an abnormal state. Therefore, the non-contact power transmission device of this aspect can reliably detect the intrusion of foreign matter during power feeding by the power feeding device.

In the second aspect of the present invention, the non-contact power transmission device performs power transmission using electromagnetic induction between the power feeding device and the power receiving device. The power receiving device includes a base body, a secondary coil that is provided on the base body and generates an electromotive force according to the magnetic flux received from the power feeding device, and a cover that is attached to the base body and covers the secondary coil And. Furthermore, the non-contact power transmission device includes a capacitance sensor that detects foreign matter around the cover, and a monitoring unit that monitors a signal detected by the capacitance sensor.

According to the second aspect, the non-contact power transmission device includes a capacitance sensor that detects foreign matter around the cover and a monitoring unit that monitors a signal detected by the capacitance sensor. It is possible to operate the capacitance sensor before starting the power feeding operation by the power feeding device, and to check the normal operation of the capacitance sensor by the monitoring unit. Thereby, it can prevent that the electric power feeding operation | movement by a electric power feeder is started with an electrostatic capacitance sensor in an abnormal state. Therefore, the non-contact power transmission device of this aspect can reliably detect the intrusion of foreign matter during power feeding by the power feeding device.

In a third aspect of the present invention, a power supply device that supplies power using electromagnetic induction to a power receiving device of a non-contact power transmission device disposed opposite to the power receiving device is provided on a base, the base, and a magnetic flux A cover that is attached to the base and covers the primary coil, a capacitance sensor that detects foreign matter around the cover, and a monitoring unit that monitors a signal detected by the capacitance sensor It has.

In a fourth aspect of the present invention, a power receiving device that receives power transmitted from a power feeding device of a non-contact power transmission device is provided on a base and the base, and is generated according to a magnetic flux received from the power feeding device. A secondary coil that generates electric power, a cover that is attached to the base and covers the secondary coil, a capacitance sensor that detects foreign matter around the cover, and a signal detected by the capacitance sensor are monitored. And a monitoring unit.

According to the present invention, the non-contact power transmission device can reliably detect the intrusion of foreign matter around the cover of the power feeding device or the power receiving device.

It is a figure which shows the structural example of the non-contact electric power transmission apparatus which concerns on embodiment. FIG. 2 is an external view showing a state where the vehicle is installed in a parking space when the power feeding device of the non-contact power transmission device shown in FIG. 1 is laid on the ground and the power receiving device is mounted on the vehicle. It is a block diagram which shows the structural example of a foreign material detection part. (A), (B), (C) It is a figure which shows an example of the sectional side view of a feeding coil unit. It is a flowchart which shows an example of the non-contact electric power transmission control and foreign material detection control which concern on this embodiment. It is a flowchart which shows an example of a foreign material detection part abnormality process. It is a flowchart which shows an example of a foreign material penetration | invasion process. It is a figure which shows the structure of the conventional non-contact electric power transmission apparatus. It is sectional drawing of the electric power feeder (power receiving apparatus) of FIG. 8, (a) is a plane sectional view, (b) is a sectional side view.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In addition, this invention is not limited by this embodiment.

FIG. 1 is a diagram illustrating a configuration example of a non-contact power transmission apparatus according to an embodiment. FIG. 2 is an external view of a state where the electric propulsion vehicle is installed in the parking space.

As shown in FIG. 1, the non-contact power transmission device receives a voltage from a commercial power supply 6 and generates a magnetic field, and a power receiving device 4 that receives a magnetic field from the power supply device 2 and receives power as power. And.

The power supply device 2 generates a magnetic flux (magnetic field) by receiving a power supply box 8 as a power supply unit connected to the commercial power supply 6, an inverter unit 10 that receives the output of the power supply box 8, and an output from the inverter unit 10. The feeding coil unit 12 having a primary coil 44 (indicated as a coil unit in FIG. 1), a capacitance sensor, a foreign matter detection unit 14 for detecting foreign matter, and a monitoring unit 17 to be described later are provided. , A power supply control unit (for example, a microcomputer; expressed as a control unit in FIG. 1) 16 for controlling the power supply device 2 is provided. The commercial power source 6 is a 200V commercial power source which is a low frequency AC power source, for example.

The power receiving device 4 generates an electromotive force according to the magnetic flux received from the power feeding coil unit 12 and has a power receiving coil unit 18 having a secondary coil 45 (denoted as a coil unit in FIG. 1), and an output of the power receiving coil unit 18. A rectifying unit 20 for receiving, a battery 22 as a load for receiving an output from the rectifying unit 20, and a power receiving control unit (for example, a microcomputer; expressed as a control unit in FIG. 1) 24 for controlling the power receiving device 4 are provided.

The primary coil 44 and the secondary coil 45 may be plate coils or solenoid coils. Further, the primary coil 44 and the secondary coil 45 are preferably formed of a metal having high conductivity, for example, copper. However, another material such as silver or aluminum may be used.

FIG. 2 shows an example in which the power supply coil unit 12 is laid on the ground and supplies power to the power receiving device 4 mounted on the electric propulsion vehicle. As shown in FIG. 2, the power supply coil unit 12 is laid on the ground, and the power supply box 8 is erected at a position separated from the power supply coil unit 12 by a predetermined distance, for example. On the other hand, the power receiving coil unit 18 is attached to, for example, a vehicle body bottom (for example, a chassis).

As shown in FIG. 2, when power is supplied from the power feeding device 2 to the power receiving device 4, the user appropriately moves the vehicle in order to place the power feeding coil unit 12 and the power receiving coil unit 18 facing each other. After the power feeding coil unit 12 and the power receiving coil unit 18 are disposed to face each other, the power feeding control unit 16 controls the drive of the inverter unit 10, thereby generating a high frequency between the power feeding coil unit 12 and the power receiving coil unit 18. Create an electromagnetic field. The power receiving device 4 takes out electric power from the high frequency electromagnetic field and charges the battery 22 with the taken out electric power.

The power reception control unit 24 determines a power command value according to the detected remaining voltage of the battery 22. The power supply control unit 16 receives the power command value determined by the power reception control unit 24 via wireless communication. The power supply control unit 16 compares the power supply detected from the power supply coil unit 12 with the power command value received from the power reception control unit 24, and drives the inverter unit 10 so that the value of the power supply power becomes the power command value. . The power reception control unit 24 detects the received power during power supply, and changes the power command value transmitted to the power supply control unit 16 so that the battery 22 is not overcurrent or overvoltage.

The foreign object detector 14 detects whether there is a foreign object around the cover. Here, the “periphery of the cover” refers to a region through which magnetic lines of force generated by the power feeding device 2 pass during power transmission, such as a high-frequency electromagnetic field region and the vicinity thereof. It shall refer to the area where temperature is generated. In the present embodiment, the foreign object detection unit 14 is provided in the power feeding coil unit 12 as shown in FIG. The place where the foreign object detection unit 14 is provided is not limited to this. For example, it may be provided outside the feeding coil unit 12 or may be provided in the power receiving device 4. Specifically, for example, the power receiving coil unit 18 may be provided.

Note that the “foreign matter” in the present disclosure is an object that may enter the periphery of the cover, and in particular, the contactless charging device (in this embodiment, the power feeding device 2 or the power receiving device) is heated by an electromagnetic field. 4) Metal pieces that may cause damage.

FIG. 3 is a block diagram illustrating a configuration example of the foreign matter detection unit 14. FIG. 4 is a diagram illustrating an example of a partial cross-sectional view of the power feeding coil unit 12 of the power feeding device 2.

As shown in FIG. 4A, the feeding coil unit 12 includes a substrate 42 as a base, a primary coil 44 provided on the substrate 42, and attached to the substrate 42. The cover 40 which covers a side and the foreign material detection part 14 installed in the back surface of the cover 40 are provided. As described above, the cover 40 is attached to the substrate 42 so as to cover the upper side and the side of the primary coil 44, whereby the primary coil 44 disposed on the substrate 42 can be protected.

As shown in FIG. 3, the foreign matter detection unit 14 includes an electrode 30, a voltage supply unit 32, a C / V conversion unit 34, and a signal processing unit 36. The monitoring unit 17 receives the signal processed by the signal processing unit 36 and determines whether the capacitance sensor is operating normally by monitoring whether or not the signal is changed. is doing.

In FIG. 4A, the position where the foreign object detection unit 14 is installed is not limited to the back surface of the cover 40, and may be installed at a position away from the back surface of the cover 40, for example. However, even in that case, the electrode 30 of the foreign matter detection unit 14 is installed on the back surface of the cover 40 so that the capacitance between the electrode 30 and the foreign matter 38 that has entered the cover 40 can be measured and protected from the outside. Preferably it is done. That is, the electrode 30 of the foreign matter detection unit 14 is preferably installed between the cover 40 and the primary coil 44, and is preferably installed at a location near the surface of the cover 40.

Note that “on the cover” in the present disclosure means on the outer surface of the cover or above the outer surface of the cover.

Further, as shown in FIG. 4B, the foreign matter detection unit 14 or the electrode 30 of the foreign matter detection unit 14 may be incorporated in the cover 40 as long as it is not exposed to the outside. Thereby, the distance with the foreign material which invaded on the cover 40 is shortened, and foreign material detection can be performed with higher accuracy.

Moreover, the foreign substance detection part 14 or the electrode 30 of the foreign substance detection part 14 may be installed on the upper side of the cover 40 and on the rear side as shown in FIG. As a result, foreign matter can be detected with high accuracy even around the cover on the side of the cover 40.

4A to 4C show an example in which the foreign object detection unit 14 is provided in the power feeding device 2, but the foreign object detection unit 14 may be provided in the power receiving device 4. It is the same. Specifically, the power receiving coil unit 18 of the power receiving device 4 is provided with a secondary coil 45 in place of the primary coil 44 in FIGS. 4A to 4C. Other configurations are the same as those shown in FIGS. 4A to 4C.

As shown in FIG. 3, the voltage supply unit 32 is connected to the electrode 30 and applies a predetermined potential with respect to the ground (GND) potential to the electrode 30. In the case where a voltage is applied to the electrode 30 by the voltage supply unit 32, when the foreign matter 38 is placed on the cover 40 as shown in FIG. 4A, the electrostatic capacitance C1 is between the electrode 30 and the foreign matter 38. appear. The capacitance C1 is expressed by Equation 1.

In Equation 1, ε0 is the dielectric constant of vacuum, εr is the relative dielectric constant between the electrode 30 and the foreign material 38 (in FIG. 4A, the relative dielectric constant of the cover), and S is the opposite electrode of the electrode 30 and the foreign material 38. The minimum area, d, is the distance between the electrode 30 and the foreign material 38. Therefore, the foreign matter detection unit 14 can confirm that the foreign matter 38 has approached the electrode 30 based on the variation in the capacitance C1 between the electrode 30 and the foreign matter 38.

The C / V conversion unit 34 converts the capacitance C1 into a voltage value. In the present embodiment, when the capacitance between the foreign object 38 and the GND potential is C2, the C / V conversion unit 34 converts the capacitance value of the capacitance C1 + C2 into a corresponding voltage value.

The signal processing unit 36 transmits a signal corresponding to the voltage value converted by the C / V conversion unit 34, that is, a signal corresponding to the measured capacitance value to the monitoring unit 17.

[Battery charging operation by non-contact power transmission]
Next, contactless power transmission control according to the present embodiment will be described with reference to the flowchart of FIG. Specifically, the control related to the determination of the normal operation of the foreign object detection unit 14 by the monitoring unit 17 and the control related to power transmission including the foreign object intrusion process will be described. Here, as shown in FIG. 2, it is assumed that the power feeding device 2 is laid on the ground and the power receiving device 4 is mounted on the vehicle, and the power feeding device 2 and the power receiving device 4 face each other before the start of step S1. Make it not exist. That is, it is assumed that the vehicle needs to be moved in order to supply power (the power receiving device 4 faces the power supply device 2). Further, when the vehicle approaches the power supply device 2 for power supply, the vehicle or the power reception control unit 24 is configured to wirelessly communicate between the power reception device 4 and the power supply device 2 until they stop. It is assumed that a trigger signal including a control command is transmitted to the power supply control unit 16.

First, the vehicle or the power reception control unit 24 transmits a vehicle approach trigger signal to the power supply control unit 16 via wireless communication (S1). When the power supply control unit 16 receives a control command included in the trigger signal from the vehicle or the power reception control unit 24, the power supply control unit 16 starts the capacitance measuring operation by the foreign matter detection unit 14. At this time, the monitoring unit 17 starts monitoring the change in the signal received from the foreign object detection unit 14 (S2). Here, in order to supply power, since the vehicle body and the power receiving device 4 mounted on the vehicle body approach the foreign object detection unit 14, the surrounding environment is changed by the power receiving coil unit 18 and the like included in the vehicle body and the power receiving device 4, A change in capacitive coupling occurs. Therefore, when the foreign object detector 14 is operating normally, a change occurs in the capacitance value measured by the foreign object detector 14 in S3 ("YES" in S3). At this time, since the monitoring unit 17 can detect a change in capacitance based on the signal received from the signal processing unit 36, the monitoring unit 17 transmits a detection result to the power supply control unit 16, and the flow proceeds to S4. In S <b> 4, the foreign object detection unit 14 measures the capacitance when the foreign object 38 is not present on the cover 40 of the power feeding device 2 in a state where the vehicle is stopped, for example, and stores the capacitance as an initial value. After the storage of the initial value by the foreign matter detection unit 14 is completed, the power supply control unit 16 starts power supply from the power supply coil unit 12 to the power reception coil unit 18 by instructing the inverter unit 10 to start power transmission. The flow proceeds to S6. In addition, although the foreign material detection part 14 shall measure an initial value in the state which the vehicle stopped, it is not limited to this. For example, the foreign matter detection unit 14 may hold a predetermined initial value in advance and use the held value as the initial value, or may measure the initial value at a timing other than the above before the start of power feeding. It doesn't matter.

On the other hand, when no change occurs in the capacitance value measured by the foreign object detector 14 in S3 ("NO" in S3), the process proceeds to the foreign object detector abnormal process (S5).

FIG. 6 is a flowchart showing an example of the foreign object detection unit abnormality process. When the process proceeds to the foreign object detection unit abnormality process, the power supply device 2 first notifies the abnormality of the abnormality detection unit 14 by a notification means such as a display or sound. For example, notification is made by the speaker 46 shown in FIG. 2 (S21).

Next, the power supply control unit 16 stops the function of the power supply apparatus 2 (S22), and ends the foreign matter detection unit abnormality process. Thereafter, the foreign object detection unit 14 ends the foreign object detection operation (S11). Thereby, the power feeding operation by the power feeding device 2 is not performed. As described above, according to this aspect, the normal operation of the foreign object detection unit 14 can be confirmed before the power supply operation by the power supply device 2 is started, and the power supply by the power supply device 2 while the foreign object detection unit 14 is in an abnormal state. It is possible to prevent the operation from starting. In addition, after the “notification of abnormality of the abnormality detection unit 14 (S21)” and before “stop of the function of the power supply device 2 (S22)”, the power supply control unit 16 has any abnormality other than the foreign matter detection unit 14. After confirming that there is no abnormality other than the foreign matter detection unit 14, the control of “stopping the function of the power supply device 2 (S22)” may be performed.

In S6, the power supply controller 16 compares the capacitance measured by the foreign object detector 14 during power supply with the initial value stored in S4, and whether or not a foreign object has entered during power supply, that is, It is determined whether or not the capacitance measured by the foreign matter detection unit 14 exceeds an initial value. If it is determined that a foreign object has entered during power supply (“YES” in S6), the process proceeds to a foreign object intrusion process (S7) for controlling transmission power. Note that the foreign object intrusion determination is not limited to the above-described criteria. For example, when the absolute value of the difference between the electrostatic capacitance measured by the foreign object detector 14 during power supply and the initial value stored in S4 exceeds a predetermined value, it may be determined that a foreign object has entered. .

FIG. 7 is a flowchart showing an example of foreign object intrusion processing. When the process proceeds to the foreign object intrusion process, the power feeding device 2 first notifies the abnormality of the abnormality detection unit 14 by a notification means such as a display or sound. For example, the notification is made by the speaker 46 shown in FIG. 2 (S31).

Next, the power supply control unit 16 determines whether or not the capacitance value measured by the foreign object detection unit 14 exceeds a preset setting value while continuing the power supply (S32). For example, the set value is set to a capacitance value that can be taken when the foreign object is a metal object. In addition, as said setting value, you may use the other value according to the kind of foreign material to detect.

When it is determined that the capacitance exceeds the set value (“YES” in S32), the power supply control unit 16 transmits the transmission power from the power supply coil unit 12 to the power reception coil unit 18 by a predetermined amount (for example, 1 / 2) Control transmission power such as reducing or stopping power transmission (S33). Further, the notification means such as display or sound notifies that the transmission power is controlled by the foreign object intrusion (S34), the foreign object intrusion process is terminated, and the flow proceeds to S9.

On the other hand, when it is determined in step S32 that the capacitance does not exceed the set value (“NO” in S32), the power supply control unit 16 bypasses S33 and S34 and ends the foreign substance intrusion processing, and the flow Shifts to S9.

In S6 of FIG. 5, when it is determined that no foreign object has entered during power supply (“NO” in S6), the power supply control unit 16 causes the inverter unit 10 to continue power transmission (S8), and the flow is as follows. The process proceeds to S9. In S <b> 9, the power supply control unit 16 confirms whether there is an instruction to interrupt power transmission for reasons such as foreign object removal by a person or use of a car.

In S9, when there is an instruction to interrupt power transmission (“YES” in S9), the power feeding control unit 16 instructs the inverter unit 10 to end power transmission, and the power from the power feeding coil unit 12 to the power receiving coil unit 18 is reached. Supply is stopped (S11). Further, the foreign matter detection unit 14 ends the capacitance measuring operation (S11).

On the other hand, when there is no instruction to interrupt the power transmission (“NO” in S9), the power supply control unit 16 determines whether the charging is completed (S10). When the charging is not completed (“NO” in S10), the flow returns to S6, while when the charging is completed (“YES” in S10), the power supply control unit 16 ends the power supply and detects foreign matter. The unit 14 ends the foreign object detection operation (S11).

In FIG. 5, the process of S9 is performed after S8. However, the process is not limited to this. For example, the power supply control unit 16 confirms whether or not there is an instruction to interrupt power transmission from the start of power supply in S4, and if there is an instruction to interrupt power transmission, the inverter unit 10 terminates power transmission. The power supply from the power supply coil unit 12 to the power receiving coil unit 18 may be terminated, and the foreign object detection unit 14 may end the foreign object detection operation (S11).

As described above, according to the present embodiment, the foreign matter detection unit 14 having a capacitance sensor capable of detecting foreign matter existing around the cover and the monitoring unit 17 that monitors normal operation of the foreign matter detection unit 14 are provided. Therefore, the normal operation of the foreign object detection unit 14 can be confirmed before the power supply operation by the power supply device 2 is started, and the power supply operation by the power supply device 2 is started while the foreign object detection unit 14 is in an abnormal state. Can be prevented. Accordingly, it is possible to always safely and reliably detect the intrusion of foreign matter around the cover during power feeding, particularly the intrusion of foreign matter between the primary coil 44 and the secondary coil 45.

Note that the present disclosure is not limited to the above-described embodiment.

For example, in addition to or in place of providing a foreign object detection unit (capacitance sensor) in the power feeding device, a foreign object detection unit (capacitance sensor) and a monitoring unit may be provided in the power receiving device. At this time, the trigger for starting monitoring (see S <b> 1 in FIG. 5) in the monitoring unit of the power receiving apparatus may be performed by, for example, approaching a relative positional relationship between the power receiving apparatus and the power feeding apparatus. More specifically, for the approach of the relative positional relationship, for example, the power receiving device or the power feeding device may measure a signal indicating that the relative positional relationship between the power receiving device and the power feeding device is approached, You may receive via the wire communication or radio | wireless communication etc. from the exterior of a power receiving apparatus or electric power feeding apparatus.

This makes it possible to monitor the operation of the foreign matter detection unit that detects foreign matter around the cover of the power receiving device. Therefore, even when the monitoring unit is provided in the power receiving device, it is possible to always safely and reliably detect intrusion of foreign matter around the cover during power feeding, as in the above-described embodiment.

In the above-described embodiment, the power supply device is laid on the ground and the power reception device is mounted on the electric propulsion vehicle. However, the power reception device is laid on the ground and the power supply device is mounted on the electric propulsion vehicle. The same applies to cases.

As described above, the contactless power transmission device of the present invention can reliably detect foreign matter that has entered the periphery of the cover during power feeding from the power feeding device to the power receiving device, so that, for example, a person or an object approaches carelessly or mistakenly. This is useful for a safety system related to power supply to a power receiving device provided in a potential electric propulsion vehicle.

2 Power feeding device 4 Power receiving device 14 Foreign matter detection unit (capacitance sensor)
17 Monitoring unit 40 Cover 42 Substrate (base)
44 Primary coil 45 Secondary coil

Claims

A non-contact power transmission device that performs power transmission using electromagnetic induction between a power feeding device and a power receiving device,
The power supply device
A substrate;
A primary coil provided on the substrate and generating magnetic flux;
A cover attached to the base body and covering the primary coil;
The non-contact power transmission device is
A capacitance sensor for detecting foreign matter around the cover;
A non-contact power transmission device comprising: a monitoring unit that monitors a signal detected by the capacitance sensor.
The contactless power transmission device according to claim 1,
The non-contact power transmission device, wherein the capacitance sensor is provided between the primary coil and the cover.
The contactless power transmission device according to claim 1,
The monitoring unit monitors a change in the signal of the capacitance sensor, triggered by a distance between the power feeding device and the power receiving device, and if there is no change in the signal during a predetermined period, A non-contact power transmission device that determines that there is an abnormality in a capacitance sensor.
A non-contact power transmission device that performs power transmission using electromagnetic induction between a power feeding device and a power receiving device,
The power receiving device is:
A substrate;
A secondary coil that is provided on the base body and generates an electromotive force according to the magnetic flux received from the power feeding device;
A cover attached to the base body and covering the secondary coil;
The non-contact power transmission device is
A capacitance sensor for detecting foreign matter around the cover;
A non-contact power transmission device comprising: a monitoring unit that monitors a signal detected by the capacitance sensor.
The contactless power transmission device according to claim 4,
The monitoring unit monitors a change in the signal of the capacitance sensor, triggered by a distance between the power feeding device and the power receiving device, and if there is no change in the signal during a predetermined period, A non-contact power transmission device that determines that there is an abnormality in a capacitance sensor.
A power feeding device that performs power feeding using electromagnetic induction to a power receiving device of a non-contact power transmission device arranged oppositely,
A substrate;
A primary coil provided on the substrate and generating magnetic flux;
A cover attached to the substrate and covering the primary coil;
A capacitance sensor for detecting foreign matter around the cover;
And a monitoring unit that monitors a signal detected by the capacitance sensor.
A power receiving device that receives power transmitted from a power supply device of a non-contact power transmission device,
A substrate;
A secondary coil that is provided on the base body and generates an electromotive force according to the magnetic flux received from the power feeding device;
A cover attached to the substrate and covering the secondary coil;
A capacitance sensor for detecting foreign matter around the cover;
A power receiving apparatus comprising: a monitoring unit that monitors a signal detected by the capacitance sensor.