JP7648670B2 - Coil unit and coil monitoring system - Google Patents

Description

The present invention relates to a coil unit and a coil monitoring system.

A known method of supplying power to a battery installed in an electric vehicle is contactless power supply. In contactless power supply, power is supplied to the battery installed in the electric vehicle by sending power from a power supply device installed underground on the power transmission side to a power receiving device on the power receiving side installed in the electric vehicle.

When performing maintenance work on underground power supply equipment, it is necessary to close roads due to excavation work. Because closing the roads interrupts traffic, it is desirable to carry out maintenance work on power supply equipment in a well-planned manner and in a short time.

Patent document 1 discloses a power supply device (coil unit) used for contactless power supply. The power transmission device has a power transmission side rectifier circuit, an inverter, and a power transmission side resonant circuit including a power transmission side coil.

JP 2023-004370 A

However, because the power supply device described in Patent Document 1 is placed underground, it is not possible to determine whether or not it has broken down. For this reason, the power supply device described in Patent Document 1 has the problem that maintenance work on the power supply device cannot be planned. In addition, the power supply device described in Patent Document 1 has the problem that the location of the power supply device that is the target of maintenance work cannot be specified in advance, which results in a long period of time that roads are closed due to maintenance work.

The first object of the present invention is to provide a coil unit and a coil monitoring system that can grasp the state of the coil even when it is buried underground. The second object of the present invention is to identify in advance the location of the coil that is the subject of maintenance work.

In order to solve the above problem, according to one aspect of the present invention,
A coil unit that is buried underground and supplies power to vehicles traveling on a road in a non-contact manner,
One or more coils;
a sensor for monitoring the condition of the coil;
A coil unit is provided, comprising:

In order to solve the above problem, according to one aspect of the present invention,
The coil unit of the present embodiment,
a control center that monitors information from the sensors about the coils;
A coil monitoring system is provided, comprising:

In order to solve the above problem, according to one aspect of the present invention,
One or more coils that are buried underground and that supply power to vehicles traveling on a road in a non-contact manner;
a sensor that is an ammeter for measuring a current value flowing through the coil, or a resistance meter for measuring a resistance value when a current is passed through the coil;
and a control center for monitoring a state of the coil based on information from the sensor.

The coil unit of the present invention allows the coil's condition to be monitored even when it is buried underground, allowing maintenance work to be carried out in a planned manner. In addition, the coils that require maintenance work can be identified in advance, shortening the time that roads are closed.

FIG. 1 is a schematic diagram showing a configuration of a coil monitoring system according to a first embodiment. FIG. 2A is a perspective view of the coil unit according to the first embodiment. FIG. 2B is a front view of the coil unit according to the first embodiment. FIG. 3 is an exploded perspective view showing the coil and ferrite housed in the case. FIG. 4A is a plan view of the coil unit according to the second embodiment. FIG. 4B is a front view of the coil unit according to the second embodiment. FIG. 5A is a plan view of a coil unit according to a third embodiment. FIG. 5B is a perspective view for explaining the arrangement of the sensors according to the third embodiment. FIG. 6A is a diagram for explaining the arrangement of sensors in the coil unit of the fourth embodiment. FIG. FIG. 6B is a diagram for explaining another arrangement of sensors in the coil unit according to the fourth embodiment. FIG. 7A is a schematic diagram of a coil unit according to the fifth embodiment. FIG. 7B is a perspective view showing the coil and ferrite housed in the case in the fifth embodiment. FIG. 8A is a schematic diagram of a coil unit according to a sixth embodiment. FIG. 8B is a perspective view showing the case and the aluminum plate in the sixth embodiment. FIG. 9 is a diagram showing a configuration of a coil monitoring system according to the seventh embodiment. FIG. 10 is a diagram showing a configuration of a coil monitoring system according to the eighth embodiment.

The coil unit and coil monitoring system of one embodiment of the present invention will be described in detail below with reference to the attached drawings. The coil unit and coil monitoring system of the present invention are not limited to the embodiment described below. The coil monitoring system of this embodiment is a system that monitors the state of a coil included in a coil unit that is used for contactless power supply and supplies power to a vehicle traveling on a road.

[First embodiment]
(Configuration of coil monitoring system)
1 is a schematic diagram showing a configuration of a coil monitoring system 10 according to embodiment 1. Note that all of the attached drawings are schematic diagrams and do not show actual dimensions.

As shown in FIG. 1, the coil monitoring system 10 has a coil unit 20 including a coil 21 and a sensor 26, and a management center 30. The coil monitoring system 10 sends measurements taken by the sensor 26 to the management center 30 along with identification information for the coil 21, and monitors the state of the coil 21 based on the measurements. If the management center 30 detects an abnormality in the coil 21, it identifies the position of the coil 21. The coil unit 20 is connected to a power source 11 via an inverter (not shown), and sends power from the power source 11 to a non-contact power receiving device 13 in the electric vehicle 12. The power sent to the non-contact power receiving device 13 is stored in a battery 14.

Figure 2A is a perspective view of the coil unit 20 of the first embodiment, and Figure 2B is a front view of the coil unit 20 of the first embodiment. Figure 3 is an exploded perspective view showing the coil 21 and the ferrite 23 housed in the case 24.

As shown in Figures 2A, 2B and 3, the coil unit 20 has one or more coils 21 and a sensor 26 for observing the state of the coil 21 from outside the coil 21. The coil unit 20 may further have a ferrite 23. In this embodiment, the coil unit 20 has a coil 21, a ferrite 23, a case 24, a housing 25 and a sensor 26. In this embodiment, the coil unit 20 has four cases 24 housed in the housing 25, and each case 24 houses a coil 21 and a ferrite 23.

The coil 21 is a Litz wire wound in a spiral shape in a plane. The outer shape of the coil 21 is a plate shape with holes. In this embodiment, the coil 21 is fixed to a coil substrate (not shown) to maintain its shape. The shape of the coil substrate in a plan view is a rectangular ring shape. There is no particular limitation on the method of fixing the coil 21 to the coil substrate. The coil 21 may be fixed to the coil substrate with an adhesive or with an adhesive tape.

The number of coils 21 is one or two or more. In this embodiment, the number of coils 21 is four. When viewed in a plan view, the multiple coils 21 are preferably arranged along at least one of a first direction along the direction of travel of vehicles traveling on a road and a second direction perpendicular to the first direction. In this embodiment, since the four cases 24 are arranged along the first direction and the second direction, the four coils 21 are also arranged along the first direction and the second direction. Note that the coil 21 may be a resonant circuit including a capacitor.

The ferrite 23 is disposed on the rear side of the coil 21 and directs and concentrates the magnetic lines of force generated by the coil 21. The ferrite 23 is formed in a plate shape, and the planar shape of the ferrite 23 is a rectangular ring shape.

The case 24 houses the coil 21 and the ferrite 23. A through hole 24c that opens to the front and back surfaces of the case 24 is located in the approximate center of the case 24. The case 24 has a case body 24a and a case lid 24b. There are no particular limitations on the material of the case 24 (case body 24a and case lid 24b) as long as it is insulating, can transmit magnetic lines of force, and has the rigidity to house the above components. Examples of materials for the case 24 include polycarbonate resin material and polypropylene resin material.

The housing 25 houses multiple cases 24 and a sensor 26. As described above, the cases 24 house the coil 21 and the ferrite 23. The housing 25 has a housing body 25a and a housing lid 25b. The material of the housing 25 (housing body 25a and housing lid 25b) is not particularly limited as long as it has insulating properties and is rigid enough to house the above components. Examples of materials for the housing 25 include polycarbonate resin material and polypropylene resin material.

The sensor 26 directly or indirectly observes the state of the coil 21. The type of the sensor 26 is not particularly limited as long as it can perform the above-mentioned functions. Examples of the types of the sensor 26 include a temperature sensor for measuring temperature, a deformation sensor for measuring strain, and a magnetic sensor for measuring magnetism. Examples of the temperature sensor include an infrared camera, an optical fiber sensor (optical time domain reflectometer: OTDR), or an optical fiber grating. Examples of the deformation sensor include an optical fiber sensor, an optical fiber grating, and a sensor.

In this embodiment, the sensor 26 is a temperature sensor. The case where the sensor 26 is an infrared camera will be described below. The sensor 26 is installed at a position that does not overlap with the case 24 in a plan view. The sensor 26 is installed, for example, at the upper end in the housing 25 of the coil unit 20, and observes the case 24 in the housing 25. In this embodiment, the number of sensors 26 is two. Also, in this embodiment, the sensors 26 are each arranged at the end of each of the housing 25 in the first direction in a plan view, at the center in a direction along a second direction perpendicular to the first direction in a plan view, and at a position that overlooks the case 24 from a position higher than the case 24. In Figures 2A and 2B, the sensor 26 on the right side of the figure monitors, for example, the coils 21 inside the two cases 24 on the right side of the figure. Also, the sensor 26 on the left side of the figure monitors, for example, the coils 21 inside the two cases 24 on the left side of the figure.

The sensor 26 is configured to be wirelessly connectable to a receiver installed in a control box 27 on the ground. That is, in this embodiment, the sensor 26 measures the temperature of the coil 21 and transmits a signal obtained by converting the temperature information wirelessly to the receiver installed in the control box 27. In this way, since the sensor 26 is wirelessly connected to the receiver, even if the sensor 26 is placed around the coil 21 of the coil unit 20, no cable or the like for the sensor 26 is placed. This allows the power sent from the power source 11 via the control box 27 to be appropriately sent to the non-contact power receiving device 13 in the electric vehicle 12. Note that the connection between the sensor 26 and the receiver is not limited to being wireless, and may be wired. Also, the receiver may be placed in a location other than the control box 27.

The timing at which the sensor 26 measures the temperature of the coil 21 is not particularly limited. The sensor 26 may measure the temperature of the coil 21 constantly, at a predetermined interval, or based on a predetermined schedule.

The sensor 26 may be disposed inside the case 24 or outside the case 24. In this embodiment, the sensor 26 is disposed outside the case 24 and inside the housing 25 from the viewpoint of observing the state of the multiple coils 21. The number of sensors 26 is not particularly limited as long as it is possible to observe the state of all the coils 21 disposed inside the case 24. The number of sensors 26 may be one or more.

The control box 27 includes an inverter and a receiving unit, not shown. The inverter adjusts the voltage and frequency of the direct current sent from the power source 11 and sends it to the coil 21. The receiving unit receives a status signal of the coil 21 sent from the sensor 26 and transmits it to the management center 30 together with the identification information of the coil 21. The receiving unit is configured to be wirelessly connectable to the sensor 26. In this embodiment, the control box 27 is placed on the ground near the power source 11.

The management center 30 monitors the state of the coil 21 based on the measurement value of the coil 21 by the sensor 26. The management center 30 has a known arithmetic processing device. In this embodiment, the arithmetic processing device monitors the state of the coil 21 based on the temperature of the coil 21. Specifically, if the temperature of the coil 21 is within a predetermined range, it is determined that the coil 21 is normal, and if the temperature of the coil 21 is outside the predetermined range, it is notified that an abnormality is occurring in the coil 21.

The identification information of the coil 21 sent from the sensor 26 is linked to the position information of the coil 21 by the management center 30. The position information is information that specifies the location where the coil 21 is installed, and is, for example, data indicating an address or a position on a map. When the management center 30 detects an abnormality in the measurement value of the coil 21, it specifies the position of the coil 21 from the identification information or position information of the coil 21. The management center 30 notifies the administrator of the measurement value, identification information, and position information of the coil 21 in which the abnormality was detected. The management center 30 may further notify the person in charge of maintenance work of the measurement value, identification information, and position information of the coil 21.

Now, the operation of the coil monitoring unit will be described. First, power from the power source 11 is sent to the coil 21 via the inverter in the control box 27. At this time, high-frequency power is supplied to the coil 21 of the coil unit 20 and the coil of the non-contact power receiving device 13, and a magnetic flux is generated by electromagnetic induction from the coil 21 of the coil unit 20 toward the coil of the non-contact power receiving device 13. Also, at this time, an induced electromotive force is generated in the coil of the non-contact power receiving device 13. As a result, power is supplied contactlessly from the coil 21 of the coil unit 20 to the coil of the non-contact power receiving device 13.

As described above, the coil unit 20 has a sensor 26. In this embodiment, the sensor 26 monitors the temperature of the coil 21. The sensor 26 measures the temperature of the coil 21 at regular intervals. The temperature information measured by the sensor 26 is sent to the control box 27, and the information received by the control box 27 is sent to the management center 30 together with the identification information of the coil 21.

The management center 30 monitors the state of the coil 21 based on the temperature information of the coil 21 sent from each control box 27. Specifically, if the temperature of the coil 21 is within a predetermined range, it determines that the coil 21 is normal, and if the temperature of the coil 21 is outside the predetermined range, it notifies that an abnormality is occurring in the coil 21.

(effect)
As described above, according to the coil monitoring system 10 of the present embodiment, since it has the sensor 26 for monitoring the state of the coil 21 from outside the coil 21, it is possible to detect the state of the coil 21 before an abnormality occurs. Furthermore, when an abnormality occurs in the coil 21, the position of the coil 21 that requires maintenance work is identified in advance. This allows the coil 21 to be replaced in a planned manner before an abnormality occurs in the coil 21, and the time that roads are closed due to maintenance work can be shortened.

[Embodiment 2]
Next, a coil monitoring system according to embodiment 2 will be described. The coil monitoring system according to this embodiment differs from the coil monitoring system 10 according to embodiment 1 only in the configuration of the coil unit 40. Therefore, the coil unit 40 will be mainly described here, and the same components as those in the coil monitoring system 10 according to embodiment 1 will be denoted by the same reference numerals and will not be described again.

(Configuration of coil monitoring system)
The coil monitoring system of the present embodiment includes a coil unit 40 including a coil 21 and a sensor 46 , and a management center 30 .

(Configuration of coil unit)
FIG. 4A is a plan view of the coil unit 40 of the second embodiment, and FIG. 4B is a front view of the coil unit 40 of the second embodiment.

As shown in Figures 4A and 4B, the coil unit 40 has one or more coils 21 and a sensor 46 for observing the state of the coil 21. The coil unit 40 may further have a ferrite 23. In this embodiment, the coil unit 40 has a coil 21, a ferrite 23, a case 24, a housing 25, and a sensor 46. In this embodiment, the coil unit 40 has four cases 24 housed in the housing 25, and each case 24 houses a coil 21, a ferrite 23, and a sensor 46.

The sensor 46 directly or indirectly observes the state of the coil 21. The sensor 46 is a deformation sensor. In this embodiment, the sensor 46 is an optical fiber grating. The sensor 46 may be disposed inside the case 24 or outside the case 24. In this embodiment, the sensor 46 is disposed inside the case 24. In this embodiment, the light source and the detection unit of the sensor 46 are disposed in the control box 27 on the ground (not shown).

The number of sensors 46 is not particularly limited. The number of sensors 46 may be one or more. In this embodiment, the number is four. The sensor 46 has a diffraction grating portion 46a. The number of diffraction grating portions 46a is not particularly limited. The number of diffraction grating portions 46a may be one or more. The number of diffraction grating portions 46a can be set appropriately according to the size of the coil 21. In this embodiment, six diffraction grating portions 46a are arranged for one sensor (optical fiber grating) 46. In this embodiment, when the coil 21 is viewed in a plane, the diffraction grating portions 46a are arranged so as to be equally spaced around the coil 21. In addition, when the coil 21 is viewed from the front, the height of the diffraction grating portions 46a is arranged so as to be the same height as the height of the coil 21. The diffraction grating portions 46a may be arranged, for example, on the center side and the outer periphery side of the coil 21.

The management center 30 monitors the state of the coil 21 based on the measured values obtained from the information from the sensor 46. The management center 30 has a known arithmetic processing device. In this embodiment, the arithmetic processing device monitors the state of the coil 21 based on the degree of deformation of the coil 21. Specifically, if the degree of deformation of the coil 21 is within a predetermined range, it is determined that the coil 21 is normal, and if the degree of deformation of the coil 21 is outside the predetermined range, it is notified that an abnormality is occurring in the coil 21.

(effect)
As described above, the coil monitoring system of the present embodiment has the same effects as those of the first embodiment.

In this embodiment, an optical fiber grating is used as the sensor 46 to observe the degree of deformation of the coil 21, but the object of observation with the optical fiber grating does not have to be the degree of deformation of the coil 21. For example, as shown in embodiment 1, the temperature of the coil 21 may be measured with the optical fiber grating. In other words, the optical fiber grating can function as both a temperature sensor and a deformation sensor.

[Embodiment 3]
Next, a coil monitoring system according to embodiment 3 will be described. The coil monitoring system according to this embodiment differs from the coil monitoring system 10 according to embodiment 1 only in the configuration of the coil unit 50. Therefore, the coil unit 50 will be mainly described here, and the same components as those in the coil monitoring system 10 according to embodiment 1 will be denoted by the same reference numerals and will not be described again.

(Configuration of coil monitoring system)
The coil monitoring system of the present embodiment includes a coil unit 50 including a coil 21 and a sensor 56 , and a management center 30 .

(Configuration of coil unit)
FIG. 5A is a plan view of a coil unit 50 according to the third embodiment, and FIG. 5B is a perspective view for explaining the arrangement of a sensor 56 according to the third embodiment.

As shown in Figures 5A and 5B, the coil unit 50 has one or more coils 21 and a sensor 56 for observing the state of the coil 21. The coil unit 50 may further have a case 24, a tray 52, and a ferrite 23. In this embodiment, the coil unit 50 has a coil 21, a tray 52, a ferrite 23, a housing 25, and a sensor 56. In this embodiment, the coil unit 50 has four cases 24 housed in the housing 25, and each case 24 houses a coil 21, a tray 52, a ferrite 23, and a sensor 56.

The tray 52 is disposed on the rear side of the coil 21. The tray 52 is formed with a first groove 52a in which the sensor 56 is disposed. The method of fixing the sensor 56 to the tray 52 is not particularly limited. The sensor 56 may be fixed to the tray 52 with an adhesive, with an adhesive tape, or may be sealed with resin.

The sensor 56 directly or indirectly observes the state of the coil 21. In this embodiment, the sensor 56 is a temperature sensor and an optical fiber sensor. The sensor (temperature sensor) 56 is disposed on the tray 52. In this embodiment, the light source and the detection unit of the sensor 56 are disposed in the control box 27. The sensor 56 is disposed so as to be located at a position corresponding to the coil 21 when viewed in a plan view.

The management center 30 monitors the state of the coil 21 based on the measured values obtained from the information from the sensor 56. The management center 30 has a known arithmetic processing device. In this embodiment, the arithmetic processing device monitors the state of the coil 21 based on the temperature of the coil 21. Specifically, if the temperature of the coil 21 is within a predetermined range, it is determined that the coil 21 is normal, and if the temperature of the coil 21 is outside the predetermined range, it is notified that an abnormality is occurring in the coil 21.

(effect)
As described above, the coil monitoring system of the present embodiment has the same effects as those of the first embodiment.

In this embodiment, an optical fiber sensor is used as the sensor 56, but an optical fiber grating may also be used. In this embodiment, the sensor 56 observes the temperature of the coil 21, but the object observed with the optical fiber grating does not have to be the temperature of the coil 21. For example, the object observed with the optical fiber grating may be the degree of deformation (strain). In other words, the optical fiber sensor can function as both a temperature sensor and a deformation sensor.

[Fourth embodiment]
Next, a coil monitoring system according to a fourth embodiment will be described. The coil monitoring system according to the present embodiment differs from the coil monitoring system according to the third embodiment only in the arrangement of the optical fiber sensors. Therefore, the same components as those in the coil monitoring system according to the third embodiment will be denoted by the same reference numerals and the description thereof will be omitted.

Figure 6A is a diagram for explaining the arrangement of the sensor 56 in the coil unit of embodiment 4, and Figure 6B is a diagram for explaining another arrangement of the sensor 56 in the coil unit of embodiment 4.

The sensor 56, which is an optical fiber sensor, is placed on the tray 52 and installed in the coil unit. There may be one sensor 56 or multiple sensors. As shown in Figures 6A and 6B, the sensor 56 may be placed at a position corresponding to a diagonal line of the tray 52. There may also be two sensors 56 as shown in Figure 6B, or there may be one sensor 56 as shown in Figure 6A. Here, when one sensor 56 is placed on a diagonal line of the tray 52, it is bent at a predetermined bending radius or more as shown in Figure 6A.

(effect)
As described above, the coil monitoring system of the present embodiment has the same effects as those of the first embodiment.

[Embodiment 5]
Next, a coil monitoring system according to embodiment 5 will be described. The coil monitoring system according to this embodiment differs from the coil monitoring system 10 according to embodiment 1 only in the configuration of the coil unit 60. Therefore, the coil unit 60 will be mainly described here, and the same components as those in the coil monitoring system 10 according to embodiment 1 will be denoted by the same reference numerals and will not be described again.

(Configuration of coil monitoring system)
The coil monitoring system of the present embodiment includes a coil unit 60 including a coil 21 and a sensor 66 , and a management center 30 .

(Configuration of coil unit)
FIG. 7A is a schematic diagram of a coil unit 60 according to the fifth embodiment, and FIG. 7B is a perspective view showing the coil 21 and the ferrite 23 housed in the case 24 according to the fifth embodiment.

As shown in Figures 7A and 7B, the coil unit 60 has one or more coils 21 and a sensor 66 for observing the state of the coil 21. The coil unit 60 may further have a case 24 and a ferrite 23. In this embodiment, the coil unit 60 has a coil 21, a ferrite 23, a case 24, a housing 25, and a sensor 66. In this embodiment, the coil unit 60 has four cases 24 housed in the housing 25, and each case 24 houses a coil 21, a ferrite 23, and a sensor 66.

The sensor 66 directly or indirectly observes the state of the coil 21. In this embodiment, the sensor 66 is a magnetic sensor. In this embodiment, the sensor (magnetic sensor) 66 is disposed in the ferrite 23. More specifically, it is disposed in a position closer to the center of the ferrite 23. By disposing it in a position closer to the center of the ferrite 23, the sensor 66 can measure magnetism more accurately.

The management center 30 monitors the state of the coil 21 based on the measurement value from the sensor 66. The management center 30 has a known arithmetic processing device. In this embodiment, the arithmetic processing device monitors the state of the coil 21 based on magnetism. Specifically, if the magnetism of the coil 21 is within a predetermined range, it is determined that the coil 21 is normal, and if the magnetism of the coil 21 is outside the predetermined range, it is notified that an abnormality is occurring in the coil 21.

(effect)
As described above, the coil monitoring system of the present embodiment has the same effects as those of the first embodiment.

Sixth Embodiment
Next, a coil monitoring system according to embodiment 6 will be described. The coil monitoring system according to this embodiment differs from the coil monitoring system 10 according to embodiment 1 only in the configuration of the coil unit 70. Therefore, the coil unit 70 will be mainly described here, and the same components as those in the coil monitoring system 10 according to embodiment 1 will be denoted by the same reference numerals and will not be described again.

(Configuration of coil monitoring system)
The coil monitoring system of the present embodiment includes a coil unit 70 including a coil 21 and a sensor 76 , and a management center 30 .

(Configuration of coil unit)
FIG. 8A is a schematic diagram of a coil unit 70 according to the sixth embodiment, and FIG. 8B is a perspective view showing a case 24 and an aluminum plate according to the sixth embodiment.

8A and 8B, the coil unit 70 has one or more coils 21 and a sensor 76 for observing the state of the coils 21. The coil unit 70 may further have a case 24, a ferrite 23, and an aluminum plate 78. In this embodiment, the coil unit 70 has two or more coils 21, a ferrite 23, a case 24, a housing 25, a sensor 76, and an aluminum plate 78. In this embodiment, the coil unit 70 has four cases 24 housed in the housing 25, and each case 24 houses a coil 21 and a ferrite 23.

The aluminum plate 78 adjusts the resonant frequency of the coil 21. The aluminum plate 78 is disposed on the rear side of the case 24 (housing 25) at a predetermined distance from the ferrite 23. The aluminum plate 78 may be configured so that the distance between the aluminum plate 78 and the ferrite 23 is adjustable. A second groove 78a in which the sensor 76 is disposed is formed in the aluminum plate 78. There is no particular limitation on the method of fixing the sensor 76 to the aluminum plate 78. The sensor 76 may be fixed to the aluminum plate 78 with an adhesive, with adhesive tape, or sealed with resin.

The sensor 76 directly or indirectly observes the state of the coil 21. In this embodiment, the sensor 76 is a temperature sensor and an optical fiber sensor. The sensor (temperature sensor) 76 is disposed on an aluminum plate 78. In this embodiment, the light source and detection unit of the sensor 76 are disposed together with the control box 27. The sensor 76 is disposed so as to be at a position corresponding to the coil 21 when viewed in a plan view.

The management center 30 monitors the state of the coil 21 based on the measurement value from the sensor 76. The management center 30 has a known arithmetic processing device. In this embodiment, the arithmetic processing device monitors the state of the coil 21 based on the temperature of the coil 21. Specifically, if the temperature of the coil 21 is within a predetermined range, it is determined that the coil 21 is normal, and if the temperature of the coil 21 is outside the predetermined range, it is notified that an abnormality is occurring in the coil 21.

(effect)
As described above, the coil monitoring system of the present embodiment has the same effects as those of the first embodiment.

In this embodiment, an optical fiber sensor is used as the sensor 76, but an optical fiber grating may also be used. In this embodiment, the temperature of the coil 21 is observed, but the object of observation with the optical fiber grating does not have to be the temperature of the coil 21. For example, the object of observation with the optical fiber grating may be the degree of deformation (strain). In other words, the optical fiber grating can function as both a temperature sensor and a deformation sensor.

In this embodiment, the temperature is measured using the sensor (temperature sensor) 76, which is an optical fiber sensor, but it may also be used as a sensor (deformation sensor), which is an optical fiber sensor. In this case, the sensor 76 may measure the strain of the aluminum plate 78, or may measure the strain of the case 24. In this way, the strain of the coil 21 may be indirectly measured by measuring the strain of the aluminum plate 78 or the strain of the case 24.

[Embodiment 7]
Next, a coil monitoring system according to embodiment 7 will be described. Here, differences from the coil monitoring system 10 according to embodiment 1 will be mainly described, and configurations similar to those of the coil monitoring system 10 according to embodiment 1 will be denoted by the same reference numerals and descriptions thereof will be omitted.

(Configuration of coil monitoring system)
FIG. 9 is a diagram showing a configuration of a coil monitoring system 80 according to the seventh embodiment.

As shown in FIG. 9, the coil monitoring system 80 has one or more coils 21 buried in the ground, a sensor 86 for observing the state of the coils 21, and a management center 30. The coil monitoring system 80 may further have a case 24 and a ferrite 23. In this embodiment, the coil monitoring system 80 has two or more coils 21, a ferrite 23, a housing 25, a sensor 86, and a management center 30. In this embodiment, the coil monitoring system 80 has four cases 24 housed in the housing 25, and each case 24 houses a coil 21 and a ferrite 23.

The sensor 86 directly or indirectly observes the state of the coil 21. In this embodiment, the sensor 86 is an ammeter. The sensor (ammeter) 86 is disposed between the coil 21 and the inverter in the control box 27. In this embodiment, the sensor 86 is disposed on the ground together with the control box 27. The ammeter 86 may be disposed in the control box 27.

The management center 30 monitors the state of the coil 21 based on the measurement value from the sensor 86. The management center 30 has a known arithmetic processing device. In this embodiment, the arithmetic processing device monitors the state of the coil 21 based on the value of the current flowing through the coil 21. Specifically, if the value of the current flowing through the coil 21 is within a predetermined range, it is determined that the coil 21 is normal, and if the value of the current flowing through the coil 21 is outside the predetermined range, it is notified that an abnormality is occurring in the coil 21.

(effect)
As described above, the coil monitoring system of the present embodiment has the same effects as those of the first embodiment.

[Embodiment 8]
Next, a coil monitoring system according to embodiment 8 will be described. Here, differences from the coil monitoring system 10 according to embodiment 1 will be mainly described, and configurations similar to those of the coil monitoring system 10 according to embodiment 1 will be denoted by the same reference numerals and descriptions thereof will be omitted.

(Configuration of coil monitoring system)
FIG. 10 is a diagram showing a configuration of a coil monitoring system 90 according to the eighth embodiment.

As shown in FIG. 10, the coil monitoring system 90 has one or more coils 21, a sensor 96 for observing the state of the coils 21, and a management center 30. The coil monitoring system 90 may further have a case 24 and a ferrite 23. In this embodiment, the coil monitoring system 90 has a coil 21, a ferrite 23, a housing 25, a sensor 96, and a management center 30. In this embodiment, the coil monitoring system 90 has four cases 24 housed in the housing 25, and each case 24 houses a coil 21 and a ferrite 23.

The sensor 96 monitors the state of the coil 21. In this embodiment, the sensor 96 is a resistance meter. The sensor (resistance meter) 96 is disposed between the coil 21 and the control box 27. In this embodiment, the sensor 96 is disposed on the ground together with the control box 27. The sensor (resistance meter) 96 may be installed inside the control box 27.

The management center monitors the state of the coil 21 based on the measurement value by the sensor 96. The management center 30 has a known arithmetic processing device. In this embodiment, the arithmetic processing device monitors the state of the coil 21 based on the resistance value. Specifically, if the resistance value of the coil 21 is within a predetermined range, it is determined that the coil 21 is normal, and if the resistance value of the coil 21 is outside the predetermined range, it is notified that an abnormality is occurring in the coil 21.

(effect)
As described above, the coil monitoring system of the present embodiment has the same effects as those of the first embodiment.

<Modification of the First Embodiment>
The coil unit 20 may further include a sensor (not shown) for measuring the temperature of parts other than the coil 21. In this case, the temperature of parts other than the coil 21 of the sensor is measured at regular intervals in synchronization with the sensor 26. The temperature information measured by the sensor is sent to the control box 27, and the temperature information received by the control box 27 is sent to the management center 30 together with the identification information of the coil 21. The management center 30 determines the state of the coil 21 based on the temperature information of the sensor 26 and the temperature information of the sensor. This makes it possible to monitor the state of the coil 21 based on the temperature information of the coil 21, taking into account the temperature outside the coil unit 20.

REFERENCE SIGNS LIST 10, 80, 90 Coil monitoring system 11 Power source 12 Electric vehicle 13 Non-contact power receiving device 14 Battery 20, 40, 50, 60, 70 Coil unit 21 Coil 52 Tray 23 Ferrite 24 Case 24a Case body 24b Case lid 24c Through hole 25 Housing 25a Housing body 25b Housing lid 26, 46, 56, 66, 76, 86, 96 Sensor 27 Control box 30 Management center 46a Diffraction grating section 52a First groove 78 Aluminum plate 78a Second groove

Claims (5)

A coil unit that is buried underground and supplies power to vehicles traveling on a road in a non-contact manner,
One or more coils;
a fiber optic sensor for monitoring the condition of the coil;
A tray having a rectangular shape in a plan view and disposed on the rear side of the coil;
Including ,
At least a portion of the optical fiber sensor is disposed on the tray at a position corresponding to a diagonal line of the tray.
Coil unit. The coil unit according to claim 1 , wherein the optical fiber sensor is a temperature sensor. The coil unit according to claim 1 , wherein the optical fiber sensor is a deformation sensor. The coil includes two or more coils,
The optical fiber sensor further includes a housing for receiving the two or more coils and the optical fiber sensor.
The two or more coils are arranged on one surface of the housing along at least one of a first direction along a traffic direction of the vehicle traveling on a road and a second direction perpendicular to the first direction when viewed in a plan view.
The coil unit according to claim 1 . The coil unit according to claim 1 ;
a control center for monitoring information from the optical fiber sensor about the coil.
Coil monitoring system.