WO2024166871A1

WO2024166871A1 - Position detection device, electric power transmitting device, position detection method, and position detection program

Info

Publication number: WO2024166871A1
Application number: PCT/JP2024/003734
Authority: WO
Inventors: 修一郎山口; 達雄八木
Original assignee: パナソニックコネクト株式会社
Priority date: 2023-02-08
Filing date: 2024-02-05
Publication date: 2024-08-15
Also published as: JP2024112665A

Abstract

This position detection device detects position information for an electric power receiving device with respect to an electric power transmitting device with an electric power transmitting coil that wirelessly transfers electric power to and from the power receiving device having an electric power receiving coil. The position detection device comprises an electric power information detection unit that detects electric power information relating to the electric power transmitting device, and a position detection unit that detects position information for the electric power receiving device using the electric power information.

Description

Position detection device, power transmission device, position detection method, and position detection program

This disclosure relates to a position detection device, a power transmission device, a position detection method, and a position detection program.

Patent Document 1 describes a contactless power supply device that starts supplying power when a proximity sensor provided in the power transmission device detects that the power receiving unit of the power receiving device has approached the power transmission unit of the power transmission device. It is shown that this proximity sensor can be appropriately selected from among commonly known sensors, such as those that use light, those that use changes in capacitance, those that use ultrasonic waves, those that use air pressure, and those that use changes in input impedance of an excitation coil due to eddy currents caused by electromagnetic induction.

Japanese Patent Application Publication No. 2004-166459

However, for example, when a camera is used as a proximity sensor using light, it is difficult to detect whether the power transmitting unit and the power receiving unit are actually close to each other. This is because when using a camera image to confirm the position, the camera image becomes unclear due to the turbidity specific to underwater (e.g., underwater), and living things and plants may adhere to the camera lens and obstruct the field of view. In addition, when ultrasonic waves are used, the detection accuracy decreases due to noise and reflections specific to underwater (e.g., underwater), so it can only be used in limited places with little noise and reflection. In addition, GPS (Global Positioning System) sensors cannot confirm the position because radio waves cannot reach underwater. In addition, with a sensor using sound waves, the accuracy of position detection is an error of several meters, so it is difficult to actually detect whether the power transmitting device and the power receiving device are close to each other. In other words, there is a problem that it is difficult to detect the proximity of the power transmitting unit and the power receiving unit underwater using a general sensor.

The purpose of this disclosure is to provide technology that can detect whether a power transmitting device and a power receiving device are in close proximity, even underwater.

A position detection device according to one aspect of the present disclosure is a position detection device that detects position information of a power receiving device with a power receiving coil relative to a power transmitting device with a power transmitting coil that wirelessly transmits power to the power receiving device, and includes an electrical information detection unit that detects electrical information of the power transmitting device, and a position detection unit that detects position information of the power receiving device using the electrical information.

A power transmission device according to one embodiment of the present disclosure includes a position detection device and a voltage control unit that controls the voltage applied to the power transmission coil. When the position detection device detects that the power receiving device is in a position where it can be charged based on the position information of the power receiving device detected by the position detection unit, the voltage control unit applies a predetermined voltage to the power transmission coil to activate a charging control circuit in the power receiving device.

A position detection method according to one aspect of the present disclosure is a position detection method for detecting position information of a power receiving device with a power receiving coil relative to a power transmitting device with a power transmitting coil that wirelessly transmits power to the power receiving device, by detecting electrical information of the power transmitting device and using the electrical information to detect the position information of the power receiving device.

A position detection program according to one embodiment of the present disclosure is a position detection method for detecting position information of a power receiving device with a power receiving coil relative to a power transmitting device with a power transmitting coil that wirelessly transmits power to the power receiving device, and detects electrical information of the power transmitting device and uses the electrical information to detect the position information of the power receiving device.

These comprehensive or specific aspects may be realized by a system, device, method, integrated circuit, computer program, or recording medium, or by any combination of a system, device, method, integrated circuit, computer program, and recording medium.

According to this disclosure, it is possible to detect whether a power transmitting device and a power receiving device are in close proximity, even underwater.

FIG. 1 is a diagram illustrating an example of a usage environment in which an underwater power supply system according to a first embodiment is installed; FIG. 1 is a block diagram showing an example of a configuration of an underwater power supply system according to a first embodiment. FIG. 1 is a diagram showing an example of the positional relationship between a power transmitting coil and a power receiving coil of a power receiving device; FIG. 1 is a diagram showing an example of the positional relationship between a power transmitting coil and a power receiving coil of a power receiving device; FIG. 1 is a diagram showing an example of the positional relationship between a power transmitting coil and a power receiving coil of a power receiving device; FIG. 3C is a view from the −X-axis direction. FIG. 1 is a diagram showing an example of a relationship between a coupling coefficient and a transmission current of a power transmitting device according to the first embodiment; FIG. 1 is a diagram showing an example of a relationship between a coupling coefficient and a transmission power of a power transmitting device according to the first embodiment; FIG. 1 is a diagram showing an example of a relationship between a coupling coefficient and a transmission power rate of a power transmitting device according to the first embodiment; FIG. 1 is a flow diagram showing the operation of the position detection device according to the first embodiment.

Below, with appropriate reference to the drawings, detailed explanations will be given of embodiments that specifically disclose the position detection device, power transmission device, position detection method, and position detection program according to the present disclosure. However, more detailed explanations than necessary may be omitted. For example, detailed explanations of already well-known matters and duplicate explanations of substantially identical configurations may be omitted. This is to avoid the following explanation becoming unnecessarily redundant and to facilitate understanding by those skilled in the art. Note that the attached drawings and the following explanation are provided to enable those skilled in the art to fully understand the present disclosure, and are not intended to limit the subject matter described in the claims.

(Embodiment 1)
1. Underwater power supply system 1000
FIG. 1 is a diagram illustrating an example of a usage environment in which an underwater power supply system 1000 according to the first embodiment is installed. The underwater power supply system 1000 includes at least a power transmission device 100 (see FIG. 2) and a power receiving device 200 (see FIG. 2). The underwater power supply system 1000 may further include a management unit 108 (see FIG. 2). The power transmission device 100 and the power receiving device 200 each include at least one coil CL. The power transmission device 100 transmits power wirelessly (contactlessly) to the power receiving device 200 via each coil CL by a magnetic resonance method.

(1) Regarding the power transmission device 100 A part of the power transmission device 100 is installed on the ship 50. Of course, the power transmission device 100 may be installed at another location (e.g., a power supply facility 1200 installed on land) or may be entirely installed underwater. In Fig. 1, a power supply stand including a bobbin bn10 floating in water and a power supply stand including a bobbin bn11 arranged on the seabed 910 are installed to perform underwater power supply (e.g., subsea power supply).

A part of the vessel 50 is above the water surface 90 (e.g., sea surface), i.e., above the water, and another part of the vessel 50 is below the water surface 90, i.e., underwater (e.g., under the sea). The vessel 50 is movable above the water surface (e.g., above the sea) and underwater, and can move freely, for example, above a data acquisition location underwater.

In FIG. 1, a power supply stand is formed by winding a power transmission coil CLA11 and a relay coil CLC11 around the outer circumference of a cylindrical bobbin bn10. The relay coil CLC11 is not necessarily required. A power cable 280 is connected to the power transmission coil CLA11, and power is supplied from a ship 50 moored at sea via the power cable 280. The power cable 280 supports the power supply stand including the bobbin bn10, the power transmission coil CLA11, and the relay coil CLC11 in a floating state in the sea. When an underwater vehicle 70, which will be described later, enters the entrance of the floating power supply stand horizontally and stops inside the bobbin bn10, it can receive power. Therefore, in FIG. 1, power transmission is not performed at the power supply stand including the bobbin bn10.

The power supply stand including the bobbin bn11 is fixed to the top of two pillars 1101 embedded in the seabed 910. In the power supply stand, the power transmission coil CLA12 is wound around the cylindrical bobbin bn11, but the relay coil CLC is not arranged. Of course, the relay coil CLC may be arranged. For example, a power cable 280A laid on the seabed 910 is connected to the power transmission coil CLA12, and power may be supplied from the power supply equipment 1200 via the power cable 280A. The underwater vehicle 70 can enter the entrance of the power supply stand installed on the seabed 910 in the horizontal direction and receive power by staying inside the bobbin bn11. In FIG. 1, the underwater vehicle 70 is stopped inside the power supply stand including the bobbin bn11, so that power transmission is performed.

(2) Power Receiving Device 200 In Fig. 1, the power receiving device 200 is provided in a mobile underwater vehicle 70 (e.g., a submarine or a bottom drilling machine). However, the power receiving device 200 may also be provided in a fixedly installed underwater facility (e.g., a seismometer, a surveillance camera, a geothermal power generator), etc. In Fig. 1, a submarine is illustrated as an example of the underwater vehicle 70. Each power receiving coil CLB included in the power receiving device 200 is provided underwater (e.g., in the sea).

The underwater vehicle 70 is, for example, a remotely operated vehicle (ROV), an unmanned underwater vehicle (UUV), or an autonomous underwater vehicle (AUV).

The underwater vehicle 70 can submerge underwater and move freely to a specified data acquisition point based on instructions from the ship 50 or the like. Instructions from the ship 50 or the like may be transmitted by communication via each coil CL or the communication antenna 203 (see FIG. 2), or by other communication methods.

(3) Coil CL The coil CL is formed, for example, in a ring shape and insulated by being covered with a resin cover. The coil CL is formed, for example, by a cab-tire cable, a helical coil, or a spiral coil. A helical coil is a ring-shaped coil wound in a spiral shape not in the same plane but along the direction of power transmission by the magnetic resonance method. A spiral coil is a ring-shaped coil formed in a spiral shape in the same plane. The use of a spiral coil makes it possible to make the coil CL thinner. The use of a helical coil makes it possible to secure a large space inside the wound coil CL. Note that an example of a helical coil is illustrated in FIG. 1.

The coil CL used for power transmission includes a power transmission coil CLA (Primary Coil) and a power receiving coil CLB (Secondary Coil). The coil CL may also include other coils CL, such as at least one relay coil CLC (Booster Coil) arranged between the power transmission coil CLA and the power receiving coil CLB. The relay coil CLC can be considered an example of a power transmission coil, and assists the power transmission by the power transmission coil CLA. When there are multiple relay coils CLC, the relay coils CLC are arranged approximately parallel to each other, and more than half of the opening surfaces formed by the relay coils CLC overlap. The interval between the multiple relay coils CLC is, for example, equal to or greater than the radius of the relay coil CLC.

The power transmission coil CLA is the power transmission coil 107 in FIG. 2 and is provided in the power transmission device 100 (see FIG. 2). The power transmission coil CLA is wound around the bobbin bn10 and the bobbin bn11. The power receiving coil CLB is the power receiving coil 207 in FIG. 2 and is provided in the power receiving device 200 (see FIG. 2). The relay coil CLC functions as part of the power transmission coil 107 and may be provided in the power transmission device 100, in the power receiving device 200, or separately from the power transmission device 100 and the power receiving device 200. A part of the relay coil CLC may be provided in the power transmission device 100 and another part may be provided in the power receiving device 200.

The coils CL are arranged, for example, at equal intervals. The distance between adjacent coils CL (coil interval) is, for example, 5 m. The coil interval may be, for example, about half the diameter of the coil CL. Considering the attenuation of the magnetic field strength underwater (for example, under the sea), the power transmission frequency is, for example, 40 kHz or less and preferably less than 10 kHz. Furthermore, when transmitting power at a transmission frequency of 10 kHz or more, a specified simulation must be performed based on the provisions of the Radio Law, but this work can be omitted when the frequency is less than 10 kHz. Note that the lower the transmission frequency, the longer the power transmission distance, the larger the coil CL, and the longer the coil interval. Note that the transmission frequency may be a frequency higher than 40 kHz, for example, when a communication signal is superimposed.

The power transmission frequency is determined based on coil characteristics such as the inductance of the coil CL, the diameter of the coil CL, and the number of turns of the coil CL. The diameter of the coil CL is, for example, several meters to several tens of meters. The thicker the coil CL, that is, the larger the wire diameter of the coil CL, the lower the electrical resistance in the coil CL and the smaller the power loss. The power transmitted via the coil CL is, for example, 50 W or more, and may be on the order of kW.

(4) Positional information of the power receiving device 200 relative to the power transmitting device 100 In Fig. 1, power transmission is not performed at the power supply station including the bobbin bn10. This is because the underwater vehicle 70 equipped with the power receiving device 200 is not inside the power supply station which is part of the power transmitting device 100. In other words, the positional information in this case is information indicating to the power transmitting device 100 that the power receiving device 200 is not in a "chargeable area". On the other hand, the underwater vehicle 70 is stopped inside the power supply station including the bobbin bn11, so power transmission is possible. In other words, the positional information in this case is information indicating to the power transmitting device 100 that the power receiving device 200 is in a "chargeable area".

When power transfer is to be performed between the power transmission device 100 and the power receiving device 200, power transfer cannot be performed unless it is possible to detect whether the power receiving device 200 is in a "chargeable area." Therefore, we will now explain how the power transmission device 100 detects position information indicating whether the power receiving device 200 is in a "chargeable area."

2. Configuration of the power transmitting device 100 and the power receiving device 200 Next, the configuration of the underwater power supply system 1000 and the power transmitting device 100 and the power receiving device 200 provided in the underwater power supply system 1000 will be described with reference to Fig. 2. Fig. 2 is a block diagram showing an example of the configuration of the underwater power supply system according to the first embodiment. In Fig. 2, the underwater power supply system 1000 includes the power transmitting device 100 and the power receiving device 200. Note that the power transmitting device 100 includes a management unit 108 on land or at sea as a part of the power transmitting device 100. The other components of the power transmitting device 100 and the power receiving device 200 may be provided underwater.

(1) Regarding the power transmission device 100 The power transmission device 100 includes a control unit 101, a communication unit 102, an antenna 103, a storage unit 104, a high-frequency power source 105, a matching circuit 106, a power transmission coil 107, and a management unit 108. The control unit 101 includes an electric information detection unit 101a and a position detection unit 101b. The control unit 101, the communication unit 102, and the storage unit 104 may be realized as an LSI (Large Scale Integration) which is an integrated circuit. These functional blocks may be individually integrated into one chip, or may be integrated into one chip so as to include some or all of them. The control unit 101 may be a device that executes a computer program stored in the storage unit 104 (including a memory) and realizes the functional blocks of the control unit 101. The control unit 101 and the high-frequency power source 105 may be arranged as part of a management unit 108 on land (sea).

The control unit 101 controls each component block included in the power transmission device 100. The electrical information detection unit 101a detects electrical information of the power transmission device 100. The electrical information of the power transmission device 100 is, for example, electrical information of the power transmission coil 107 when a low voltage (an example of a first voltage) is applied to the power transmission coil 107 of the power transmission device 100. The electrical information may be at least one of the transmission current, the transmission voltage, the transmission power, or the transmission power rate and electrical information generated using at least one of these electrical information. The low voltage is, for example, a voltage of about 10V. Although details will be described later, when power transmission is not being performed, the electrical information of the power transmission coil 107 when a low voltage is applied to the power transmission coil 107 fluctuates depending on the positional relationship between the position of the power transmission device 100 and the position where the power receiving device 200 can be charged. The electrical information detection unit 101a detects this variable electrical information.

The position detection unit 101b detects the position information of the power receiving device 200 using the electrical information detected by the electrical information detection unit 101a. The position information detected by the position detection unit 101b indicates whether the power receiving device 200 is in a position where the storage battery 208 (see FIG. 2) can be charged. The position information detected by the position detection unit 101b may indicate in detail the positional relationship between the position of the power receiving device 200 and the position where charging is possible. That is, for example, it may indicate the distance between the power transmitting device 100 and the power receiving device. The voltage control unit 101c controls the voltage applied to the power transmitting coil 107. The position detection device 100a is formed by including at least the electrical information detection unit 101a and the position detection unit 101b of the control unit 101.

The communication unit 102 can perform wireless communication (transmission and reception) with the power receiving device 200, the management unit 108, and other devices via the antenna 103. In addition, communication between the power transmitting device 100, the power receiving device 200, and other devices may be performed using a wired cable, or communication networks such as a wired LAN (Local Area Network), a wireless LAN, LTE (Long Term Evolution), 4G (fourth generation mobile communication system), 5G (fifth generation mobile communication system), the Internet, and a VPN (Virtual Private Network). If necessary, the position detection device 100a may include the communication unit 102 in addition to the electrical information detection unit 101a and the position detection unit 101b.

The storage unit 104 stores thresholds and the like used by the position detection unit 101b, which will be described later. In addition, a memory may be provided as part of the storage unit 104, and a position detection program may be stored therein. This position detection program is executed by the control unit 101.

The high frequency power supply 105 is a power supply for transmitting power wirelessly (without contact) to the power receiving device 200. The alternating current supplied by the high frequency power supply 105 controlled by the control unit 101 is applied to the power transmitting coil 107 via a matching circuit 106. In FIG. 1, the power transmitting coil 107 is the power transmitting coils CLA11 and CLA12. Of course, the relay coil CLC11 may also be considered as the power transmitting coil 107.

The management unit 108 has, for example, a database (DB), and obtains from the control unit 101 the relative position information of the power transmission device 100 and the power receiving device 200 detected by the position detection device 100a, and stores and manages the information in the DB.

(2) Power Receiving Device 200 The power receiving device 200 includes a control unit 201, a communication unit 202, an antenna 203, a sensor 204, a rectifier 205, a matching circuit 206, a power receiving coil 207, and a storage battery 208. The control unit 201 and the communication unit 202 may be realized as an LSI, which is an integrated circuit. These functional blocks may be individually formed into single chips, or may be formed into a single chip so as to include some or all of these functional blocks.

The control unit 201 controls each component block included in the power receiving device 200. The communication unit 202 can perform wireless communication (transmission and reception) with the power transmitting device 100 and other devices via the antenna 203. The sensor 204 is, for example, a camera, and is an example of a load that consumes power from the underwater vehicle 70. The sensor 204 may also be a drive mechanism (thruster, etc.) that controls movement in the sea, as an example of a load that is mounted on the underwater vehicle 70 and consumes power. The power received via the power receiving coil 207 is stored in the storage battery 208 via the matching circuit 206 and rectifier 205 (i.e., the storage battery 208 is charged). The sensor 204, the thruster, etc. consume the power stored in the storage battery 208. The power receiving coil 207 is the power receiving coil CLB in FIG. 1.

3. Positional relationship between the power transmission coil 107 and the power receiving coil 207 Next, an example of the positional relationship between the power transmission coil 107 of the power transmission device 100 and the power receiving coil 207 of the power receiving device 200 will be described with reference to Figs. 3A, 3B, 3C, and 3D. Figs. 3A, 3B, and 3C are diagrams showing an example of the positional relationship between the power transmission coil 107 and the power receiving coil 207 of the power receiving device 200. Fig. 3D is a view seen from the arrow X in Fig. 3C. In the description of Figs. 3A to 3D, the same reference numerals are given to overlapping elements to simplify or omit the description, and different contents will be described. In the description of Figs. 3A to 3D, the XYZ axes are defined.

Specifically, in Figures 3A to 3D, the X-axis indicates the direction in which the power receiving device 200 approaches the power transmission coil 107, the Y-axis is perpendicular to the X-axis and Z-axis and indicates the width direction of the power receiving device 200, and the Z-axis is perpendicular to the X-axis and Y-axis and indicates the height direction of the power receiving device 200.

3A to 3C, the power transmission coil 107 is configured such that the first power transmission coil 107a, the second power transmission coil 107b, and the third power transmission coil 107c are connected along the moving direction of the power receiving device 200 (i.e., the X-axis direction). The third power transmission coil 107c may be the relay coil CLC11 (see FIG. 1). The first power transmission coil 107a and the second power transmission coil 107b are connected, for example, 1 m apart along the X-axis direction. The position where the power receiving device 200 can be charged is, for example, a position where at least half of the power receiving coil 207 of the power receiving device 200 is located between the first power transmission coil 107a and the third power transmission coil 107c. The antenna 103 configured in a rectangular shape is arranged to cover the upper ends of the first power transmission coil 107a to the third power transmission coil 107c in the Z-axis direction. Furthermore, the module that constitutes the communication unit 102 is located above the antenna 103 in the Z-axis direction.

FIG. 3A shows an example of the relative positional relationship of the power receiving coil 207 of the power receiving device 200 with respect to the power transmitting coil 107. Specifically, the power receiving coil 207 of the power receiving device 200 is located halfway between the first power transmitting coil 107a and the second power transmitting coil 107b. In this case, the power receiving coil 207 of the power receiving device 200 has reached a position where the power receiving device 200 can be charged (see point C in FIG. 4).

FIG. 3B shows another example of the relative positional relationship of the power receiving coil 207 of the power receiving device 200 with respect to the power transmitting coil 107. Specifically, the power receiving coil 207 of the power receiving device 200 is located in the range from the first power transmitting coil 107a to the third power transmitting coil 107c. In this case, the power receiving coil 207 of the power receiving device 200 is located in a stable position where the power receiving device 200 can be charged (see point D in FIG. 4).

3C and 3D show other examples of the relative positional relationship of the power receiving coil 207 of the power receiving device 200 with respect to the power transmitting coil 107. Specifically, the power receiving coil 207 of the power receiving device 200 is located in the range from the first power transmitting coil 107a to the third power transmitting coil 107c, and is located higher along the Z axis direction compared to FIG. 3B (see FIG. 3D). In this case, the power receiving coil 207 of the power receiving device 200 is located in a more stable position where the power receiving device 200 can be charged compared to the position shown in FIG. 3B (see point E in FIG. 4). This is because the distance between the power transmitting coil 107 and the power receiving coil 207 of the power receiving device 200 is shorter in the length shown in FIG. 3C than in FIG. 3B, and the coupling coefficient is higher.

4. Detection of position information of power receiving device 200 Next, a method of detecting position information of the power receiving device 200 will be described with reference to Fig. 4, Fig. 5, and Fig. 6. Fig. 4, Fig. 5, and Fig. 6 are diagrams showing an example of a relationship between a coupling coefficient and a transmission current of a power transmitting device according to the first embodiment.

First, if the power receiving device 200 is far from the position (area) where the power transmitting device 100 can be charged, the coupling coefficient indicating the degree of magnetic coupling between the power transmitting coil 107 and the power receiving coil 207 becomes low. Then, the closer the power receiving device 200 is to the position (area) where the power transmitting device 100 can be charged, the higher the coupling coefficient indicating the degree of magnetic coupling between the power transmitting coil 107 and the power receiving coil 207 becomes. When power is not being transmitted from the power transmitting device 100 to the power receiving device 200, if a low voltage is applied to the power transmitting coil 107 of the power transmitting device 100 constantly or at regular intervals, the current (electrical information) flowing through the power transmitting coil 107 changes due to the change in the coupling coefficient. By utilizing the fact that the current (electrical information) changes due to this coupling coefficient, it is possible to detect the position information of the power receiving device 200.

Under the conditions for measuring Figure 4, the experimental results are as follows. When the power receiving device 200 is very far from the power transmitting device 100 (point A), the current value of the power transmitting coil 107 is 2 Arms or more. Naturally, the power receiving device 200 is not in a position where charging is possible. When the power receiving device 200 is slightly far from the power transmitting device 100 (point B), the current value of the power transmitting coil 107 is about 1.7 Arms. At this time, the power receiving device 200 is still not in a position where charging is possible.

When the power receiving device 200 is in a position where it can just barely charge the power transmitting device 100 (point C), the current value of the power transmitting coil 107 is about 1.2 Arms. When the power receiving device 200 is in a position where it can fully charge the power transmitting device 100 (point D), the current value of the power transmitting coil 107 is about 1 Arms. When the power receiving device 200 is in a position where it can charge the power transmitting device 100 most efficiently (point E), the current value of the power transmitting coil 107 is 1 Arm or less. Note that the power receiving device 200 is in a position where it can just barely charge the power transmitting device 100 means, for example, a position where the power supply efficiency is equal to or greater than a predetermined ratio, such as 50%. In this case, if the power supply efficiency is 50% or more, it means that "the power receiving device 200 is in a position where it can be charged". Naturally, if the power supply efficiency is less than 49%, it means that "the power receiving device 200 is not in a position where it can be charged".

4, the position detection unit 101b can determine that "the power receiving device 200 is in a position where it can be charged" when the coupling coefficient is 0.169 or more. Therefore, when the current of the power transmission coil 107 becomes lower than about 1.3 Arms (threshold value), the position detection unit 101b can detect that the power transmission device 100 is in a position where the power receiving device 200 can be charged. At the same time, when the current of the power transmission coil 107 is higher than about 1.3 Arms, the position detection unit 101b can detect that the power transmission device 100 is not in a position where the power receiving device 200 can be charged. In other words, the position information of the power receiving device 200 relative to the power transmission device 100 can be detected simply by detecting the current of the power transmission coil 107 of the power transmission device 100. Therefore, there is no need to use a new sensor such as a camera to detect the position information of the power receiving device 200 relative to the power transmission device 100. Furthermore, in this embodiment, if a new sensor such as a camera is further used to detect the position information of the power receiving device 200, it is possible to detect the position information of the power receiving device 200 with higher accuracy. Note that the position information of the power receiving device 200 relative to the power transmitting device 100 can be detected by detecting electrical information of not only the power transmitting coil CLA in FIG. 1 but also the relay coil CLC. In any case, the position information of the power receiving device 200 relative to the power transmitting device 100 can be detected simply by detecting the current of the power transmitting coil 107 of the power transmitting device 100.

Incidentally, since the coupling coefficient also changes depending on the position of the receiving coil 207 relative to the transmitting coil 107 (points A to E), the position detection unit 101b can detect and estimate the position (distance) of the receiving coil 207 relative to the transmitting coil 107. By detecting and estimating the position (distance) of the receiving coil 207 relative to the transmitting coil 107, more accurate position detection is possible.

In FIG. 4, the position information of the power receiving device 200 is detected by the current flowing through the power transmission coil 107, but as shown in FIG. 5 or FIG. 6, the position information of the power receiving device 200 may be detected by the power transmission or power transmission rate of the power transmission coil 107. In either case, under the same conditions as in FIG. 4, when the coupling coefficient is greater than about 0.169, it is detected that "the power receiving device 200 is in a position where it can be charged." The power and power factor when the coupling coefficient is 0.169 are the threshold values. However, when making a judgment based only on the current flowing through the power transmission coil 107, it is possible to do so by detecting only the current, but when making a judgment based on the power transmission or power transmission rate, information on the power transmission voltage is also required. Therefore, it is easy to detect only the current. The electric information detection unit 101a described above can detect the current, power, and power factor of the power transmission coil 107.

As is clear from Figures 4 to 6, the position detection unit 101b can use the electrical information to detect not only whether the power receiving device 200 is located in a position where the power transmitting device 100 can be charged, but also how far the power receiving device 200 is from the power transmitting device 100.

In addition, in Figures 4 to 6, the low voltage (an example of the first voltage) applied to the power transmission coil 107 constantly or at regular time intervals is, for example, 10V. This low voltage may be a number other than 10V, but if the voltage is set to a certain level or higher, the power receiving device 200 may start receiving power. Therefore, it is preferable that the voltage be low enough that the power receiving device 200 does not start receiving power.

Also, if the position detection unit 101b does not detect the position of the power receiving device 200, i.e., if charging is not possible, the communication unit 102 of the power transmitting device 100 may transmit alert information to the power receiving device 200 via the antenna 103. This makes it possible to efficiently encourage charging when the power receiving device 200 needs charging. The communication unit 202 of the power receiving device 200 receives this alert information via the antenna 203. The alert information may indicate that the position detection unit 101b has not detected the position of the power receiving device 200, i.e., that charging is not possible. This alert is particularly effective when the power receiving device 200 transmits information indicating that charging is necessary via the communication unit 202 and the antenna 203, and the power transmitting device 100 receives the information via the communication unit 102 and the antenna 103. In other words, it is preferable to communicate the alert information when charging has not started despite the power receiving device 200 needing charging. In addition, information regarding the distance between the power receiving device 200 and the power transmitting device 100 may be communicated as part of the alert at this time.

Note that communication between the power transmitting device 100 and the power receiving device 200 is preferably by radio waves, and the

communication units

102 and 202 provided in each of them preferably communicate by radio waves. This allows for efficient communication.

Furthermore, the communication area in which the

communication units

102, 202 can communicate is wider than the area in which the power transmission device 100 can charge the power receiving device 200. This allows the communication unit 102 of the power transmission device 100 to transmit information such as alert information to the power receiving device 200 via the antenna 103 when the position detection unit 101b does not detect the position of the power receiving device 200, i.e., when charging is not possible. Note that in FIG. 2, the communication unit 102 and antenna 103 are provided outside the position detection device 100a, but they may be part of the position detection device 100a.

In addition, when the position detection unit 101b detects from the detected position information of the power receiving device 200 that the power receiving device 200 is in a position where it can be charged, the voltage control unit 101c may apply a predetermined voltage required to start the control unit 201 of the power receiving device 200 to the power transmitting coil 107. In addition, when the position detection unit 101b detects from the detected position information of the power receiving device 200 that the power receiving device 200 is in a position where it can be charged, the voltage control unit 101c may apply a predetermined voltage for charging the power receiving coil 207 of the power receiving device 200 to the power transmitting coil 107. Note that the predetermined voltage required to start the control unit 201 and the predetermined voltage for charging the power receiving coil 207 of the power receiving device 200 may be voltages of the same magnitude or may be voltages of different magnitudes.

5. Flow of detecting position information of the power receiving device 200 Next, a flow of detecting position information of the power receiving device 200 will be described with reference to Fig. 7. Fig. 7 is a flow diagram showing the operation of the position detection device according to the first embodiment. Note that the following flow may be considered as a flow of processing executed by the control unit 101 using a position detection program stored in the storage unit 104. In addition, the following description will be given of a case where the current of the power transmitting coil 107 is detected as electrical information as in Fig. 4, but it may of course be replaced with the transmitted power or the transmitted power rate.

In FIG. 7, first, the voltage control unit 101c applies a low voltage (e.g., 10V) to the power transmission coil 107 (St1). Next, the electrical information detection unit 101a detects the current in the power transmission coil 107 (St2). Then, the position detection unit 101b judges whether the detected current is smaller than the threshold value. If the detected current is smaller than the threshold value (St3, YES), it is determined that "the power receiving device 200 is in a position where charging is possible" (St4). In this case, the voltage control unit 101c increases the voltage applied to the power transmission coil 107. As a result, the control unit 201 of the power receiving device 200 is turned on (St5). Then, power supply from the power transmission device 100 to the power receiving device 200 starts, and the position detection flow ends.

On the other hand, if the detected current is equal to or greater than the threshold (St3, NO), the position detection unit 101b detects that the power receiving device 200 is not in a position where charging is possible (St6). In this case, the voltage control unit 101c stops applying voltage to the power transmission coil 107 (St7).

As described above, the position detection device 100a according to this embodiment detects the position information of the power receiving device 200 relative to the power transmitting device 100 having the power transmitting coil 107 that transmits power wirelessly to the power receiving device 200 having the power receiving coil 207. The position detection device 100a includes an electrical information detection unit 101a that detects electrical information of the power transmitting device 100, and a position detection unit 101b that detects the position information of the power receiving device 200 based on the electrical information. As a result, the position detection device 100a or the power transmitting device 100 can detect whether the power transmitting device 100 and the power receiving device 200 are in close proximity even underwater.

Furthermore, in the position detection device 100a according to this embodiment, the electrical information of the power transmission device 100 is electrical information of the power transmission coil 107 of the power transmission device 100. This allows the position detection device 100a or the power transmission device 100 to detect with higher accuracy whether the power transmission device 100 and the power receiving device 200 are in close proximity, even underwater.

In addition, in the position detection device 100a according to this embodiment, the electrical information of the power transmission device 100 is the power transmission current, power transmission voltage, power transmission, or power transmission rate of the power transmission device 100. It may also be the power transmission current, power transmission voltage, power transmission, or power transmission rate of the power transmission coil 107 of the power transmission device 100. This allows the position detection device 100a or the power transmission device 100 to detect with higher accuracy whether the power transmission device 100 and the power receiving device 200 are in close proximity, even underwater.

Furthermore, the power receiving device 200 according to this embodiment has a rechargeable storage battery 208, and in the position detection device 100a, the position detection unit 101b detects whether the power receiving device 200 is in a position where it can be charged. This allows the position detection device 100a or the power transmitting device 100 to detect with higher accuracy whether the power transmitting device 100 and the power receiving device 200 are in close proximity, even underwater.

In addition, in the position detection device 100a according to this embodiment, the position detection unit 101b is connected to the communication unit 102 included in the power transmission device 100, and when the position detection unit 101b does not detect the position of the power receiving device 200, it transmits alert information to the power receiving device 200 via the communication unit 102. This allows the position detection device 100a or the power transmission device 100 to efficiently prompt the power receiving device 200 to charge when charging is required.

In addition, in the position detection device 100a according to this embodiment, the position detection unit 101b is connected to the communication unit 102 provided in the power transmission device 100, and the position detection unit 101b communicates by radio waves via the communication unit 102. This allows the position detection device 100a or the power transmission device 100 to communicate efficiently.

In addition, in the position detection device 100a according to this embodiment, the position detection unit 101b is connected to the communication unit 102 provided in the power transmission device 100, and the communication area of the communication unit 102 is larger than the power supply area to which the power transmission device 100 can supply power. This allows the position detection device 100a or the power transmission device 100 to communicate efficiently.

Furthermore, in the position detection device 100a according to this embodiment, the position detection unit 101b detects the relative position of the power receiving coil 207 with respect to the power transmitting coil 107. This allows the position detection device 100a or the power transmitting device 100 to detect with higher accuracy whether the power transmitting device 100 and the power receiving device 200 are in close proximity to each other even underwater.

The power transmission device 100 according to this embodiment also includes a position detection device 100a and a voltage control unit 101c that controls the voltage applied to the power transmission coil 107. When the position detection device 100a detects from the position information of the power receiving device 200 detected by the position detection unit 101b that the power receiving device 200 is in a position where the rechargeable storage battery 208 of the power receiving device 200 can be charged, the voltage control unit 101c applies a predetermined first voltage (for example, a voltage equal to or greater than the position detection voltage and less than the second voltage) to the power transmission coil 107 to activate the control unit 201 of the power receiving device 200. As a result, the position detection device 100a or the power transmission device 100 can detect whether the power transmission device 100 and the power receiving device 200 are close to each other even underwater, and can prepare for charging.

In addition, in the power transmission device 100 according to this embodiment, when the position detection device 100a detects, from the position information of the power receiving device 200 detected by the position detection unit 101b, that the power receiving device 200 is in a position where the storage battery 208 can be charged, the voltage control unit 101c applies a predetermined second voltage (e.g., 100V or more) to the power transmission coil 107 that is greater than the first voltage for charging the power receiving coil 207 of the power receiving device 200. As a result, the position detection device 100a or the power transmission device 100 can detect whether the power transmission device 100 and the power receiving device 200 are in close proximity to each other even underwater, and can then perform charging.

The position detection method detects the position information of the power receiving device 200 relative to the power transmitting device 100 having a power transmitting coil 107 that transmits power wirelessly to the power receiving device 200 having a power receiving coil 207, and detects electrical information of the power transmitting device 100 and detects the position information of the power receiving device 200 based on the electrical information. This allows the position detection device 100a or the power transmitting device 100 to detect whether the power transmitting device 100 and the power receiving device 200 are in close proximity even underwater.

The position detection program causes a computer to execute a position detection device 100a that detects position information of the power receiving device 200 relative to the power transmitting device 100 having a power transmitting coil 107 that wirelessly transmits power to the power receiving device 200 having a power receiving coil 207, detects electrical information of the power transmitting device 100, and detects the position information of the power receiving device 200 based on the electrical information. As a result, the position detection device 100a or the power transmitting device 100 can detect whether the power transmitting device 100 and the power receiving device 200 are in close proximity even underwater.

　Although the embodiments have been described above with reference to the attached drawings, the present disclosure is not limited to such examples. It is clear that a person skilled in the art can conceive of various modifications, amendments, substitutions, additions, deletions, and equivalents within the scope of the claims, and it is understood that these also fall within the technical scope of the present disclosure. Furthermore, the components in the above-described embodiments may be combined in any manner as long as it does not deviate from the spirit of the invention.

This application is based on a Japanese patent application (Patent Application No. 2023-017868) filed on February 8, 2023, the contents of which are incorporated by reference into this application.

The technology disclosed herein can detect whether a power transmitting device and a power receiving device are in close proximity, even underwater.

50 Ship 70 Underwater vehicle 100 Power transmitting device 101 Control unit 101a Electrical information detection unit 101b Position detection unit 101c Voltage control unit 102 Communication unit 103 Antenna 104 Memory unit 105 High frequency power source 106 Matching circuit 107 Power transmitting coil 200 Power receiving device 201 Control unit 202 Communication unit 203 Antenna 204 Sensor 205 Rectifier 206 Matching circuit 207 Power receiving coil 208 Storage battery 1000 Underwater power supply system CLA11 Power transmitting coil CLB Power receiving coil CLC11 Relay coil

Claims

A position detection device that detects position information of a power receiving device with respect to a power transmitting device having a power receiving coil that wirelessly transmits power to the power receiving device,
an electrical information detection unit that detects electrical information of the power transmitting device;
A position detection unit that detects position information of the power receiving device based on the electrical information.
Position sensing device.
The electrical information of the power transmitting device is electrical information of the power transmitting coil of the power transmitting device.
The position sensing device according to claim 1 .
The electrical information of the power transmitting device is a transmission current, a transmission voltage, a transmission power, or a transmission power rate of the power transmitting device.
3. A position detection device according to claim 1 or 2.
The power receiving device has a rechargeable storage battery,
The position detection unit detects whether the power receiving device is located at a position where the storage battery can be charged.
3. A position detection device according to claim 1 or 2.
The position detection unit is connected to a communication unit included in the power transmission device,
When the position detection unit does not detect the position of the power receiving device, the position detection unit transmits alert information to the power receiving device via the communication unit.
3. A position detection device according to claim 1 or 2.
The position detection unit is connected to a communication unit included in the power transmission device,
The position detection unit communicates by radio waves via the communication unit.
3. A position detection device according to claim 1 or 2.
The position detection unit is connected to a communication unit included in the power transmission device,
A communication area of the communication unit is larger than a power supply area in which the power transmitting device can supply power.
3. A position detection device according to claim 1 or 2.
The position detection unit detects a relative position of the power receiving coil with respect to the power transmitting coil.
3. A position detection device according to claim 1 or 2.
A position detection device according to claim 1 ;
A voltage control unit that controls a voltage applied to the power transmitting coil,
When the position detection device detects, based on the position information of the power receiving device detected by the position detection unit, that the power receiving device is located at a position where a rechargeable storage battery included in the power receiving device can be charged, the voltage control unit applies a predetermined first voltage to the power transmitting coil to activate a charge control circuit included in the power receiving device.
Power transmission equipment.
When the position detection device detects, from the position information of the power receiving device detected by the position detection unit, that the power receiving device is located at a position where the storage battery can be charged, the voltage control unit applies a predetermined second voltage to the power transmitting coil, the second voltage being higher than the first voltage for charging the power receiving coil of the power receiving device.
The power transmitting device according to claim 9 .
A position detection method for detecting position information of a power receiving device with a power transmitting coil that wirelessly transmits power to a power receiving device, the method comprising:
Detecting electrical information of the power transmitting device;
Detecting location information of the power receiving device based on the electrical information.
Position sensing method.
A position detection method for detecting position information of a power receiving device with a power transmitting coil that wirelessly transmits power to a power receiving device, the method comprising:
Detecting electrical information of the power transmitting device;
Detecting location information of the power receiving device based on the electrical information.
Make the computer do that,
Location detection program.