Power supply mat, non-contact power supply system, and moving body

Abstract

To provide a power feeding mat, a contactless power feeding system, and a moving body for appropriately guiding the moving body requesting a contactless power feeding to the power feeding mat.SOLUTION: A power feeding mat 1 includes: a power transmission coil 21 for transmitting power supplied from an external power source or an internal power source to a moving body 5 including a power receiving coil in a contactless manner; a covering sheet 22 for covering the power transmission coil 21; and a light emitting device 32 configured to emit light toward the outside when detecting that the moving body 5 is approaching it within a predetermined distance.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a power supply mat, a non-contact power supply system, and a moving body.

Background Art

[0002] Patent Document 1 discloses a power supply mat configured to be disposed on a traveling road of a vehicle and capable of transmitting power to the vehicle in a non-contact manner.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Unlike a power transmission device embedded in a road, a power supply mat can be transported and has a high degree of freedom in the installation location. Therefore, for example, in an event venue or a shelter, etc., it is installed in a place where non-contact power supply cannot be performed normally, and is assumed to be used to perform non-contact power supply to various moving bodies (vehicles, small robots, unmanned aerial vehicles, etc.) used in that place. Therefore, it is necessary to appropriately guide a moving body that requires non-contact power supply to the power supply mat.

[0005] The present invention has been made paying attention to such problems, and an object thereof is to be able to appropriately guide a moving body that requires non-contact power supply to a power supply mat.

Means for Solving the Problems

[0006] In order to solve the above problems, a power supply mat according to an aspect of the present invention includes a power transmission coil for non - contact transmission of power supplied from an external power source or an internal power source to a moving body provided with a power reception coil, a covering sheet covering the power transmission coil, and a light - emitting device configured to emit light outward when it is detected that the moving body has approached within a predetermined distance.

[0007] Moreover, a power supply mat according to an aspect of the present invention includes a power transmission coil for non - contact transmission of power supplied from an external power source or an internal power source to a moving body provided with a power reception coil, a covering sheet covering the power transmission coil, and a light - emitting device configured to emit light outward when a signal notifying the presence of the moving body is received from the moving body at a reception intensity equal to or higher than a predetermined value.

[0008] A moving body according to an aspect of the present invention further includes a wireless communication device that transmits a signal notifying the presence of the moving body to a power supply mat configured to enable non - contact power supply, a light - source detection device that detects light emitted after the signal is transmitted and detects the direction of the light source of the light, and a control device that performs an automatic driving operation to automatically perform the driving operation of the moving body. The control device is configured to correct the traveling direction of the moving body so that the traveling direction of the moving body coincides with the light - source direction when the light - source detection device detects the light - source direction of the light.

Advantages of the Invention

[0009] According to these aspects of the present invention, a moving body that requires non - contact power supply can be guided in the direction in which light is emitted, that is, the direction in which the power supply mat is arranged, so that the moving body can be appropriately guided to the power supply mat.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

Figure 3

Figure 4

DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, embodiments will be described in detail with reference to the drawings. In the following description, the same reference numerals are assigned to similar components.

[0012] FIG. 1 is a schematic configuration diagram of a non-contact power supply system 100 according to an embodiment of the present invention.

[0013] As shown in FIG. 1, the non-contact power supply system 100 includes a power supply mat 1 and a moving body 5 corresponding to non-contact power supply. In FIG. 1, for easy understanding of the invention, the power supply mat 1 and the moving body 5 are not illustrated at the actual dimensional ratio, and the ratio is changed as necessary so that the structure and the like are clear.

[0014] The power supply mat 1 includes a mat portion 2 and a power supply device 3. The power supply mat 1 is a mat configured to be able to transmit power supplied from an external power source or an internal power source to the moving body 5 in a non-contact manner. As shown in FIG. 1, the power supply mat 1 can be arranged on the ground or the floor surface, and in addition, it can also be arranged on, for example, a wall surface.

[0015] The mat portion 2 includes a power transmission coil 21 and a covering sheet 22.

[0016] The power transmission coil 21 performs non-contact power transmission to the moving body 5 that has moved onto the mat portion 2, for example, by magnetic field resonance coupling (magnetic field resonance). Note that the power transmission method is not limited to magnetic field resonance coupling, and other power transmission methods such as magnetic field coupling (electromagnetic induction), electric field coupling, and electric field resonance coupling (electric field resonance) may also be used.

[0017] The covering sheet 22 is a sheet-like member that covers the power transmission coil 21 and has a function of protecting the power transmission coil 21. In the present embodiment, the covering sheet 22 is composed of a flexible member so that the mat portion 2 can be wound or bent, for example, in a roll shape. Thereby, the mat portion 2, and thus the power supply mat 1, can be easily stored and transported. Also, in the present embodiment, the covering sheet 22 covers a plurality of power transmission coils 21.

[0018] FIG. 2 is a schematic system configuration diagram of the power supply device 3.

[0019] As shown in FIG. 2, the power supply device 3 includes a power transmission circuit 31, a light emitting device 32, a power supply side communication device 33, and a power supply control device 34.

[0020] The power transmission circuit 31 is an electric circuit that is electrically connected to an external power source (not shown), such as a power outlet, by, for example, an electric cable, and supplies the power of the external power source to the power transmission coil 21. The power transmission circuit 31 is controlled by the power supply control device 34 so that the power transmission coil 21 of the mat portion 2 and a power receiving coil (not shown) mounted on the moving body 5, which are arranged with a space therebetween, are magnetically coupled to perform non-contact power transmission, and supplies the power of the external power source to the power transmission coil 21. Note that the power supply device 3 may be configured to include an internal power source. In this case, since the power of the internal power source can be supplied, it is not necessary to configure the power supply device 3 to be connectable to an external power source.

[0021] The light emitting device 32 is composed of, for example, an LED (Light Emitting Diode), and emits light outward under the control of the power supply control device 34. In the present embodiment, the light emitting device 32 is configured to be able to emit light having directivity in an arbitrary direction in a 360-degree circumference around the mat portion 2. However, the light emitting device 32 may be configured to be able to emit light in all directions in a 360-degree circumference around the mat portion 2.

[0022] The power supply side communication device 33 includes an antenna 331 and a signal processing circuit 332 that executes various processes related to wireless communication such as modulation and demodulation of wireless signals. The power supply side communication device 33 has a short-range communication function for performing direct wireless communication between terminals without going through a base station, and can directly perform wireless communication with the mobile body 5 through short-range communication. When the power supply side communication device 33 receives a wireless signal from the outside, it transmits the wireless signal to the power supply control device 34. Also, when a signal for transmission to the outside from the power supply control device 34 is transferred, the power supply side communication device 33 generates a wireless signal including the signal and transmits it to the outside.

[0023] In this embodiment, the antennas 331 of the power supply side communication device 33 are respectively arranged at the four corners of the mat portion 2 as shown in FIG. 1. Thereby, based on the difference in the reception intensity of the wireless signals received by each antenna 331 and the difference (time difference) in the reception time of the wireless signals received by each antenna 331, the direction of the mobile body that is the transmission source of the wireless signal can be detected. For example, when a wireless signal is transmitted from the north side of north, south, east, and west, the reception intensity of the wireless signal received by the antenna 331 arranged on the north side of the mat portion 2 becomes the highest, so the direction of the mobile body 5 that is the transmission source of the wireless signal can be detected. Also, with respect to the reception time of the wireless signal received by the antenna 331 arranged on the north side of the mat portion 2, the reception time of the wireless signal received by the antenna 331 arranged at other positions is later, so the direction of the mobile body that is the transmission source of the wireless signal can be detected using the difference in reception time.

[0024] The power supply control device 34 includes a communication interface (communication I / F) 341, a memory 342, and a processor 343.

[0025] The communication interface 341 includes an interface circuit for connecting the power supply control device 34 to the internal network 35 of the power supply device 3. The power supply control device 34 is connected to the power transmission circuit 31, the light emitting device 32, the power supply side communication device 33, etc. through this communication interface 341.

[0026] The memory 342 has a storage medium such as an HDD (Hard Disk Drive), an optical recording medium, or a semiconductor memory. The memory 342 stores various computer programs and data executed in the processor 343. The memory 342 also stores data generated by a computer program and data received via the communication interface 341.

[0027] The processor 343 includes one or more CPUs (Central Processing Units) and its peripheral circuits. The processor 343 executes various processes based on various computer programs stored in the memory 342 to comprehensively control the operation of the power supply mat 1. The content of the process for guiding the moving body 5 to the power supply mat 1, which is implemented in the processor 343 and thus in the power supply control device 34, will be described later with reference to FIG. 4.

[0028] Returning to FIG. 1, the moving body 5 is, for example, a vehicle, a small robot, or a drone that supports non-contact power supply. In FIG. 1, as an example of the moving body 5, a micro pallet capable of autonomous driving is illustrated. Hereinafter, the details of the moving body 5 will be described with reference to FIG. 3.

[0029] FIG. 3 is a schematic system configuration diagram of the moving body 5.

[0030] The moving body 5 includes a power receiving device 51, a peripheral information acquisition device 52, a behavior information acquisition device 53, a state information acquisition device 54, a moving body side communication device 55, a light source detection device 56, and a moving body control device 57.

[0031] The power receiving device 51 includes a power receiving coil (not shown). The power receiving device 51 is controlled by the moving body control device 57 and is configured to supply the power received from the power supply mat 1 to the electrical loads mounted on the moving body 5. Examples of the electrical loads include a battery and a motor for driving the moving body.

[0032] The peripheral information acquisition device 52 is a device for acquiring data of objects around the moving body 5 as the peripheral information of the moving body 5. The peripheral information acquisition device 52 can be composed of a single or a plurality of devices. In this embodiment, it is composed of a camera that photographs the surroundings of the moving body 5 and a distance measuring sensor (for example, a LiDAR (Light Detection and Ranging), a millimeter-wave radar sensor, an ultrasonic sensor, etc.) for measuring the distance to an object around the moving body 5. The peripheral information of the moving body 5 acquired by the peripheral information acquisition device 52 is transmitted to the movement control device 57 via the internal network 58 of the moving body 5.

[0033] The behavior information acquisition device 53 is a device for acquiring various parameters indicating the behavior of the moving body 5 as the behavior information of the moving body 5. The behavior information acquisition device 53 can be composed of a single or a plurality of devices. In this embodiment, it is composed of a speed sensor, an acceleration sensor, a steering angle sensor, etc. The behavior information such as the speed, acceleration, and steering angle of the moving body 5 acquired by the behavior information acquisition device 53 is transmitted to the movement control device 57 via the internal network 58 of the moving body 5.

[0034] The state information acquisition device 54 is a device for acquiring various parameters indicating the state of the moving body 5 as the state information of the moving body 5. The state information acquisition device 54 can be composed of a single or a plurality of devices. In this embodiment, it is composed of a GNSS receiver that detects the current position of the moving body 5 based on each satellite radio wave received from a plurality of satellites, and a SOC sensor that detects the charging rate of the battery for driving the moving body (hereinafter referred to as "battery charging rate") [%]. The state information such as the current position and battery charging rate of the moving body 5 acquired by the state information acquisition device 54 is transmitted to the movement control device 57 via the internal network 58 of the moving body 5.

[0035] The mobile communication device 55 includes an antenna and a signal processing circuit that executes various processes related to wireless communication such as modulation and demodulation of wireless signals. Similar to the power supply side communication device 33, the mobile communication device 55 also has a short-range communication function, enabling direct wireless communication with the mobile body 5 through short-range communication. When the mobile communication device 55 receives a wireless signal from the outside, it transmits the wireless signal to the mobile control device 57. Also, when a signal to be transmitted to the outside from the mobile control device 57 is transferred, the mobile communication device 55 generates a wireless signal including the signal and transmits it to the outside.

[0036] The light source detection device 56 is a device for detecting the light emitted by the light emitting device 32 of the power supply mat 1 and detecting the direction (azimuth) of the light emitting device 32, and thus the power supply mat 1. When the light source detection device 56 detects the light emitted by the light emitting device 32 of the power supply mat 1, it detects the direction of the light emitting device 32 (light source) and transmits it as light source information to the mobile control device 57 via the internal network 58.

[0037] The light source detection device 56 according to the present embodiment includes a camera, and detects the direction of the light emitting device 32 of the power supply mat 1 based on the camera image captured by the camera. Specifically, the light source detection device 56 inputs the camera image into an identifier such as a deep neural network trained according to a learning method such as the error backpropagation method using a large number of teacher images, thereby detecting the direction of the light emitting device 32 of the power supply mat 1. Note that the camera image does not necessarily have to be captured by a dedicated camera, and may be obtained from the camera of the peripheral information acquisition device 52.

[0038] The mobile control device 57 includes a communication interface (communication I / F) 571, a memory 572, and a processor 573.

[0039] The communication interface 571 includes an interface circuit for connecting the movement control device 57 to the internal network 58. The movement control device 57 is connected to various devices mounted on the moving body 5, such as the power receiving device 51, the peripheral information acquisition device 52, the behavior information acquisition device 53, the state information acquisition device 54, the moving body side communication device 55, and the light source detection device 56, via this communication interface 571.

[0040] The memory 572 has a storage medium such as an HDD (Hard Disk Drive), an optical recording medium, or a semiconductor memory. The memory 572 stores various computer programs and data executed in the processor 573. The memory 572 also stores data generated by a computer program and data received from various devices mounted on the moving body 5 via the communication interface 571.

[0041] The processor 573 includes one or more CPUs (Central Processing Units) and its peripheral circuits. The processor 573 executes various processes based on various computer programs stored in the memory 572 to comprehensively control the operation of the moving body 5. For example, the processor 573 creates a driving plan for the moving body 5 based on peripheral information, behavior information, state information, etc., and performs an automatic driving that automatically performs driving operations related to acceleration, steering, and braking according to the driving plan. Also, when the battery charge rate of the moving body 5 decreases, the processor 343 performs a process to recover the battery charge rate.

[0042] As described above, unlike the power transmission device embedded in the road for non-contact power supply, the power supply mat 1 is transportable and has a high degree of freedom in the installation location. Therefore, it is assumed that it is installed in places where non-contact power supply cannot be performed normally, such as event venues and shelters, and is used to perform non-contact power supply to the moving body 5 used at that place. Therefore, it is necessary to appropriately guide and supply power to the moving body 5 that requires non-contact power supply to the power supply mat 1.

[0043] FIG. 4 is a diagram for explaining the content and flow of processing executed by the power supply mat 1 and the moving body 5 in order to guide the moving body 5 to the power supply mat 1 and recover the battery charge rate of the moving body 5.

[0044] In step S101, the movement control device 57 determines whether the battery charge rate of the moving body 5 is equal to or lower than a predetermined threshold value. The predetermined threshold value can be a battery charge rate suitable for starting the process for recovering the battery charge rate of the moving body 5, and can be set to any arbitrary value as appropriate according to the usage environment of the moving body 5, etc. If the battery charge rate of the moving body 5 is equal to or lower than the predetermined threshold value, the movement control device 57 proceeds to the process of step S102. On the other hand, if the battery charge rate of the moving body 5 is higher than the predetermined threshold value, the movement control device 57 ends the current process.

[0045] In step S102, the movement control device 57 starts periodic transmission of a radio signal (hereinafter referred to as "presence notification signal") for notifying the power supply mat 1 of the presence of the moving body 5 via the moving body side communication device 55, and also starts detection of a light source by the light source detection device 56. The presence notification signal may be transmitted, for example, in the traveling direction (direction of the destination) of the moving body 5, or may be transmitted over the entire circumference.

[0046] In step S103, the power supply control device 34 determines whether there is a moving body 5 that desires non-contact power supply within a predetermined distance from the power supply mat 1. In the present embodiment, when any one of the antennas 331 arranged at the four corners of the mat unit 2 receives the presence notification signal with a reception intensity equal to or higher than a predetermined value, the power supply control device 34 determines that there is a moving body 5 that desires non-contact power supply within a predetermined distance from the power supply mat 1, and proceeds to the process of step S104. On the other hand, if none of the antennas 331 receives the presence notification signal with a reception intensity equal to or higher than a predetermined value, the power supply control device 34 determines that there is no moving body 5 that desires non-contact power supply within a predetermined distance from the power supply mat 1, and ends the current process.

[0047] In step S104, the power supply control device 34 detects the direction of the moving body 5 that is the transmission source of the presence notification signal based on the difference in the reception intensity of the presence notification signal received by each antenna 331 and the difference (time difference) in the reception time of the presence notification signal received by each antenna 331.

[0048] In step S105, in order to guide the moving body 5 to the power supply mat 1, the power supply control device 34 controls the light emitting device 32 to emit light toward the direction of the moving body 5, and controls the power transmission circuit 31 to perform power supply preparation so that power can be supplied to the moving body 5 when the moving body 5 has moved to the mat portion 2 of the power supply mat 1. In the present embodiment, the light emission by the light emitting device 32 and the power supply preparation are performed simultaneously in this way. However, the power supply preparation may be performed within a predetermined period before or after the light emission by the light emitting device 32. Therefore, for example, after receiving the presence notification signal at a reception intensity equal to or higher than a predetermined value, light emission may be performed and then power supply preparation may be performed after a predetermined time has elapsed, or conversely, after receiving the presence notification signal at a reception intensity equal to or higher than a predetermined value, power supply preparation may be performed and then light emission may be performed after a predetermined time has elapsed.

[0049] In step S106, the movement control device 57 determines whether or not it has received light source information from the light source detection device 56. If the movement control device 57 has received light source information from the light source detection device 56, it proceeds to the process of step S107. On the other hand, if the movement control device 57 has not received light source information from the light source detection device 56, it performs the process of step S106 again after a predetermined time has elapsed.

[0050] In step S107, the movement control device 57 calculates the deviation angle between the traveling direction of the moving body 5 and the direction of the light emitting device 32 based on the light source information, and corrects the operation plan so that the traveling direction of the moving body 5 coincides with the direction of the light emitting device 32. Thereby, the moving body 5 can be appropriately guided toward the mat portion 2 of the power supply mat 1, so that power can be surely supplied to the moving body 5 by the power supply mat 1.

[0051] In step S108, when the mobile body 5 moves to the mat unit 2, the power supply control device 34 performs non-contact power supply to the mobile body 5.

[0052] The power supply mat 1 according to the present embodiment described above includes a power transmission coil 21 for transmitting power supplied from an external power source or an internal power source to a mobile body 5 provided with a power reception coil in a non-contact manner, a covering sheet 22 covering the power transmission coil 21, and a light emitting device 32 configured to emit light outward when it is detected that the mobile body 5 has approached within a predetermined distance.

[0053] Specifically, the light emitting device 32 is configured to detect that the mobile body 5 has approached within a predetermined distance based on the presence notification signal received from the mobile body 5 notifying the presence of the mobile body 5. In the present embodiment, when the presence notification signal is received from the mobile body 5 with a reception intensity equal to or higher than a predetermined value, it is determined that the mobile body 5 has approached within a predetermined distance, and the light emitting device 32 is configured to emit light outward.

[0054] Thereby, the mobile body 5 that requires non-contact power supply can be guided in the direction in which the light is emitted, that is, the direction in which the power supply mat 1 is arranged, and the mobile body 5 can be appropriately guided to the power supply mat 1.

[0055] Also, in the present embodiment, a plurality of antennas 331 are attached to different positions of the covering sheet 22, and the light emitting device 32 is configured to emit light in the direction of the mobile body 5 that is the transmission source of the presence notification signal, which is detected based on the difference in the reception intensity of the presence notification signal received by each antenna 331 or the difference in the reception time of the presence notification signal received by each antenna.

[0056] In addition, the mobile body 5 according to the present embodiment includes a mobile body side communication device 55 (wireless communication device) that transmits a presence notification signal for notifying the presence of the mobile body 5 to the power feeding mat 1 capable of non-contact power feeding, a light source detection device 56 that detects the light emitted after the presence notification signal is transmitted and detects the direction of the light source of the light, and a movement control device 57 (control device) that performs automatic driving for automatically performing the driving operation of the mobile body 5. And when the light source detection device 56 detects the direction of the light source of the light, the movement control device 57 is configured to correct the traveling direction of the mobile body 5 so that the traveling direction of the mobile body 5 coincides with the light source direction. Further, such a mobile body 5 and a power feeding mat 1 constitute a non-contact power feeding system 100.

[0057] Thereby, the mobile body 5 that requires non-contact power feeding can be surely guided to the power feeding mat 1, and the power feeding mat 1 can surely supply power to the mobile body 5.

[0058] As described above, the embodiments of the present invention have been described. However, the above embodiments merely show a part of the application examples of the present invention, and are not intended to limit the technical scope of the present invention to the specific configurations of the above embodiments.

Explanation of Reference Numerals

[0059] 1 Power feeding mat 5 Mobile body 21 Power transmission coil 22 Coating sheet 32 Light emitting device 55 Mobile body side communication device (wireless communication device) 56 Light source detection device 57 Movement control device (control device) 331 Antenna

Claims

Claim 1: A power transmission coil for non - contact transmission of power supplied from an external power source or an internal power source to a moving body provided with a power receiving coil; A covering sheet covering the power transmission coil; A light - emitting device configured to emit light outward when a signal notifying the presence of the moving body from the moving body is received at a predetermined reception intensity or higher; A plurality of antennas attached to the covering sheet at different attachment positions; and The light - emitting device is configured to emit light in the direction of the moving body that is the transmission source of the signal, detected based on a difference in reception intensity of the signal received by each antenna or a difference in reception time of the signal received by each antenna. A power - feeding mat. Claim 2 Performs preparation for power supply to the power transmission coil in synchronization with the timing when the light - emitting device emits light, or at a predetermined time before or after that timing. The power - feeding mat according to claim 1. Claim 3 When the signal is received at a predetermined reception intensity or higher, simultaneously perform light emission by the light - emitting device and preparation for power supply to the power transmission coil. The power - feeding mat according to claim 1. Claim 4 When the signal is received at a predetermined reception intensity or higher, perform preparation for power supply to the power transmission coil after performing light emission by the light - emitting device. The power - feeding mat according to claim 1. Claim 5 When the signal is received at a predetermined reception intensity or higher, perform light emission by the light - emitting device after performing preparation for power supply to the power transmission coil. The power - feeding mat according to claim 1. Claim 6 A non - contact power - supply system including the power - feeding mat according to claim 1 and the moving body, wherein the moving body includes a wireless communication device that transmits a signal notifying the presence of the moving body to the power - feeding mat, a light - source detection device that detects light emitted after the signal is transmitted and detects the direction of the light source of the light, and a control device that performs an automatic driving for automatically performing the driving operation of the moving body, and the control device is configured to correct the traveling direction of the moving body so that the traveling direction of the moving body coincides with the light - source direction when the light - source detection device detects the light - source direction of the light. A non - contact power - supply system.

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