Title of Invention: Wireless Power Supply System, Power Transmission Device, and Power Reception Device
Technical field
[0001]
The present invention relates to a wireless power supply system, a power transmission device, and a power reception device.
Background technology
[0002]
Conventionally, a wireless power supply technology is known in which a power transmission device installed on a road surface, such as a road, wirelessly supplies power to a power reception device installed in a vehicle. For example, Patent Literature 1 discloses a vehicle capable of receiving power from a power transmission device provided on a road surface by providing a power receiving device on the underside of the vehicle.
prior art documents
patent literature
[0003]
Patent Document 1: JP 2018-068077 A
SUMMARY OF THE INVENTION
Problems to be Solved by the Invention
[0004]
However, in the conventional wireless power supply technology, when there is a distance between a power transmission device installed on a road surface such as a road and a power reception device installed on a moving body running on the road surface, the power transmission device and the power reception device are separated. There is a risk that an obstacle such as a small animal or metal may enter the space between them, and an eddy current may be generated around the obstacle, resulting in a decrease in power supply efficiency. In addition, there is a risk that a small animal or metal that has entered between the power transmission device and the power reception device will be heated and ignite. Therefore, there is a demand for further improvement in usefulness of wireless power supply technology for wirelessly supplying power to a mobile object.
[0005]
An object of the present invention, which has been made in view of such circumstances, is to provide a wireless power feeding system, a power transmitting device, and a power receiving device that can improve the usefulness of wireless power feeding.
Means to solve problems
[0006]
The wireless power supply system according to the present invention is
A power transmission device installed on a road, comprising a power transmission coil that wirelessly transmits power, and in a state of being installed on the road, in a cross section in the width direction of the road, a perpendicular line to a coil surface of the power transmission coil is the road. a power transmission device configured to be inclined with respect to the normal to the road surface of the
a power receiving device comprising a power receiving coil that wirelessly receives power, at least part of the power receiving coil being housed in a wheel of a mobile body;
including.
[0007]
A power transmission device according to the present invention includes a power transmission coil that wirelessly transmits electric power, and in a cross section in the width direction of the road, the perpendicular to the coil surface of the power transmission coil is the perpendicular to the road surface of the road. is configured to tilt with respect to
[0008]
A power receiving device according to the present invention includes a power receiving coil that wirelessly receives electric power, and in a state in which at least part of the power receiving coil is housed in a wheel of a mobile body, the power receiving coil The perpendicular to the coil surface of the wheel is inclined with respect to the perpendicular to the contact surface of the wheel with the road surface.
Effect of the invention
[0009]
According to the present invention, it is possible to provide a wireless power supply system, a power transmission device, and a power reception device that can improve the usefulness of wireless power supply technology for wirelessly supplying power to mobile objects.
Brief description of the drawing
[0010]
1 is a schematic diagram schematically showing a wireless power supply system according to an embodiment of the present invention using a cross section in the width direction of a wheel; FIG.
2 is a schematic view schematically showing a tire-wheel assembly as an example of a wheel in the wireless power supply system according to one embodiment of the present invention, using a cross section in the width direction of the wheel; FIG.
3 is a functional block diagram schematically showing a configuration example of a power transmission device according to an embodiment of the present invention; FIG.
4 is a schematic diagram schematically showing a coil surface of a power transmission coil provided in a power transmission device according to an embodiment of the present invention and its inclination, using a cross section in the width direction of a road; FIG.
5 is a functional block diagram schematically showing a configuration example of a power receiving device according to an embodiment of the present invention; FIG.
6 is a schematic diagram schematically showing a coil surface of a power receiving coil provided in a power receiving device according to an embodiment of the present invention and its inclination, using a cross section in the width direction of a road; FIG.
7 is a schematic diagram showing an installation example of a power transmission device on a road in the wireless power supply system according to one embodiment of the present invention; FIG.
8 is a schematic diagram schematically showing a modification of the wireless power feeding system according to one embodiment of the present invention using a cross section in the width direction of the wheel; FIG.
MODE FOR CARRYING OUT THE INVENTION
[0011]
A wireless power feeding system, a power transmitting device, and a power receiving device according to one embodiment of the present invention will be described below with reference to the drawings. The same reference numerals are given to common parts and sites in each figure. In this specification, the width direction of the wheel refers to the direction parallel to the axis of rotation of the wheel. The radial direction of the wheel refers to a direction perpendicular to the axis of rotation of the wheel. The extending direction of the road or driving lane means the direction in which the road or driving lane extends. The width direction of a road or running lane refers to a direction orthogonal to the extending direction. The width direction of the moving object means a direction perpendicular to the direction in which the moving object travels.
[0012]
(Configuration of wireless power supply system)
A configuration of a wireless power supply system 1 according to an embodiment of the present invention will be described with reference to FIGS. 1 and 2. FIG.
[0013]
FIG. 1 shows a schematic diagram schematically showing a wireless power supply system 1 according to an embodiment of the present invention using a cross section in the width direction of a wheel 6 of a mobile object 5. As shown in FIG. A wireless power feeding system 1 includes a power transmitting device 2 and a power receiving device 3 . The power transmission device 2 is installed on the road 4 . The power receiving device 3 is installed in the mobile object 5 . As a result, in the wireless power supply system 1 , power is wirelessly transmitted from the power transmission device 2 to the power reception device 3 when the moving object 5 runs on the road 4 in the direction in which the road 4 extends.
[0014]
The power transmission device 2 includes a power transmission coil 21 . The power transmission device 2 wirelessly transmits power using the power transmission coil 21 . The power transmission coil 21 is positioned below the road surface of the road 4 in the vertical direction. Specifically, the power transmission coil 21 is buried below the road surface of the road 4 . In this embodiment, the power transmission coil 21 is embedded below the road surface of the road 4 so that at least a portion thereof is exposed from the road surface of the road 4 . In FIG. 1 , the power transmission coil 21 is shown schematically for the sake of simplification of explanation.
[0015]
The power receiving device 3 includes a power receiving coil 31 . The power receiving coil 31 receives power wirelessly transmitted from the power transmitting coil 21 of the power transmitting device 2 . The power receiving device 3 is installed in the mobile object 5 . In the present embodiment, in the power receiving device 3 , at least part of the power receiving coil 31 is housed in the wheels 6 of the moving body 5 . In this embodiment, the power receiving device 3 is attached to the wheels 6 of the moving body 5 so that at least part of the power receiving coil 31 is housed in the wheels 6 of the moving body 5 . However, the power receiving device 3 may be attached to the main body of the moving body 5 so that at least part of the power receiving coil 31 is housed in the wheels 6 of the moving body 5 . In FIG. 1 , the power receiving coil 31 is shown schematically for the sake of simplification of explanation.
[0016]
The road 4 has a road surface used for traffic by the moving body 5. In this specification, the “road surface” is the surface of the road 4 on which the vehicle 5 travels on the wheels 6 . In this embodiment, the road 4 is, for example, a roadway. However, the roads 4 are not limited to roadways, and may include footpaths, farm roads, forest roads, runways, parking lots, vacant lots, open spaces, and the like. The traffic of the mobile body 5 includes traveling, stopping and parking of the mobile body 5 .
[0017]
At least one driving lane 41 can be provided on the road surface of the road 4 . The travel lane 41 is a road surface area that is defined as an area on which the mobile body 5 travels. A plurality of travel lanes 41 may be provided on the road 4 in accordance with the number of mobile bodies 5 that can run in parallel. Demarcation lines such as white lines may be drawn on the road surface of the road 4 to indicate the driving lanes 41 .
[0018]
In this embodiment, the road surface of the road 4 is paved with, for example, asphalt. However, the road surface of the road 4 is not limited to asphalt, and may be made of concrete, stone, brick, soil, gravel, or the like.
[0019]
The mobile body 5 runs on the road surface of the road 4 with the wheels 6 . In this embodiment, the mobile body 5 is an automobile, such as an electric automobile or a hybrid automobile, which includes a motor as a power source. Automobiles include passenger cars, trucks, buses, motorcycles, and the like. However, the mobile object 5 is not limited to automobiles, and includes agricultural vehicles such as tractors, construction or construction vehicles such as dump trucks, airplanes, helicopters, motorized bicycles, electric bicycles, and electric wheelchairs.
[0020]
The wheels 6 are used to move the moving body 5. The wheel 6 has a contact surface that comes into contact with the road surface of the road 4 while being attached to the mobile body 5 . In this embodiment, the wheel 6 is a tire-wheel assembly in which the tire 61 is attached to the wheel 62, but is not limited to this. In this specification, the "ground contact surface" of the wheel 6 means the contact surface of the tire 61 when the wheel 6 is a tire-wheel assembly, that is, the tire 61 is mounted on an applicable rim, filled with a specified internal pressure, and It refers to the surface of the tire 61 that comes into contact with the road surface under load.
[0021]
As used herein, the term "applicable rim" refers to industrial standards that are effective in regions where pneumatic tires are produced and used. Standard rims (ETRTO's Measuring Rim in STANDARDS MANUAL, Design Rim in TRA's YEAR BOOK), but for sizes not listed in these industrial standards, it refers to a rim with a width corresponding to the bead width of a pneumatic tire. "Applicable rims" include current sizes as well as sizes that may be included in the aforementioned industrial standards in the future. As an example of "sizes to be described in the future", sizes described as "FUTURE DEVELOPMENTS" in ETRTO 2013 edition can be mentioned.
[0022]
As used herein, the term "specified internal pressure" refers to the air pressure (maximum air pressure) corresponding to the maximum load capacity of a single wheel in the applicable size and ply rating, as described in the aforementioned industrial standards such as the JATMA Year Book. In the case of sizes not listed in the aforementioned industrial standards, the air pressure (maximum air pressure) corresponding to the maximum load capacity specified for each vehicle on which the tire is mounted is used. In this specification, the "maximum load" refers to a load corresponding to the maximum load capacity of a tire of the applicable size described in the industrial standards described above, or in the case of a size not described in the industrial standards described above. means the load corresponding to the maximum load capacity specified for each vehicle on which the tire is mounted.
[0023]
FIG. 2 is a schematic diagram showing a tire-wheel assembly as an example of the wheel 6 in the wireless power supply system 1 according to one embodiment of the present invention, using a cross section in the width direction of the wheel 6. ing.
[0024]
As shown in FIG. 2, the tire 61 has a pair of bead portions 611, a pair of sidewall portions 612, and a tread portion 613. The bead portion 611 is configured such that when the tire 61 is mounted on the rim portion 621 of the wheel 62 , the radially inner side and the widthwise outer side of the bead portion 611 are in contact with the rim portion 621 . Sidewall portion 612 extends between tread portion 613 and bead portion 611 . The sidewall portion 612 is located radially outside the wheel 6 relative to the bead portion 611 . The tread portion 613 is located radially outside of the wheel 6 relative to the sidewall portion 612 and includes a contact surface of the tire 61 .
[0025]
The tire 61 is made of rubber such as natural rubber and synthetic rubber, and may include parts made of metal such as steel, such as carcasses, belts and bead wires. For example, at least part of the parts such as the carcass, belts and bead wires may be made of non-magnetic material. As a result, the tire 61 maintains the strength of the tire 61 and allows the power transmission device 2 and the power reception device 3 to be connected to each other. The existence of the metal between the two reduces the attenuation of the magnetic field generated by the power transmitting coil 21 before it reaches the power receiving coil 31, thereby increasing the efficiency of wireless power feeding from the power transmitting device 2 to the power receiving device 3. can be improved. However, at least part of the parts such as the carcass, belt and bead wires need not be made of non-magnetic material.
[0026]
Non-magnetic materials can include paramagnetic and diamagnetic materials with low magnetic permeability. As the non-magnetic material, for example, resin materials including thermoplastic resins such as polyester and nylon, thermosetting resins such as vinyl ester resins and unsaturated polyester resins, and other synthetic resins can be used. The resin material can further contain fibers such as glass, carbon, graphite, aramid, polyethylene, and ceramics as reinforcing fibers. Non-magnetic materials are not limited to resins, and any non-metallic materials including rubber, glass, carbon, graphite, aramid, polyethylene, and ceramics can be used. Furthermore, metal materials including paramagnetic materials such as aluminum or diamagnetic materials such as copper can be used as non-magnetic materials.
[0027]
The wheel 62 includes a cylindrical rim portion 621 on which the tire 61 is mounted, a hub portion 622 provided radially inside the rim portion 621 and fixed to the shaft 52 of the moving body 5, and supported by the hub portion 622. and a disc portion 623 that is fixed and supports and secures the rim portion 621 .
[0028]
The wheel 62 can be made of metal such as steel, but is not limited to this. At least a portion of the rim portion 621, hub portion 622, and disk portion 623 of the wheel 62 may be made of the non-magnetic material described above. As a result, while maintaining the strength of the wheel 62, the presence of metal such as steel between the power transmitting device 2 and the power receiving device 3 causes the magnetic field generated by the power transmitting coil 21 to attenuate before reaching the power receiving coil 31. It is possible to reduce the power supply efficiency of the wireless power supply from the power transmission device 2 to the power reception device 3 . However, at least a portion of the rim portion 621, hub portion 622, and disk portion 623 of the wheel 62 need not be made of non-magnetic material.
[0029]
In FIG. 2, the power receiving device 3 is attached to the hub portion 622 of the wheel 62 . In this state, at least part of power receiving coil 31 is housed in wheel 6 . “Accommodated in the wheel” means disposed radially inward of the outer peripheral surface of the wheel and inward of both widthwise ends of the wheel. In this embodiment, most of the power receiving coil 31 is housed in the wheel 6 .
[0030]
The power receiving device 3 is installed at a portion of the wheel 6 that does not rotate as the wheel 6 rotates, such as the cover of the hub portion 622 of the wheel 62 . As a result, since the power receiving device 3 does not change the relative position of the power receiving coil 31 inside the wheel 6 according to the rotation of the tire 61, it is easy to stably supply power wirelessly from the outside of the wheel 6. become.
[0031]
The ratio of the portion accommodated in the wheels 6 of the moving body 5 to the entire power receiving coil 31 may be determined arbitrarily. As the proportion of the entire power receiving coil 31 housed in the wheels 6 increases, obstacles are less likely to enter the space between the power transmitting coil 21 and the power receiving coil 31 during power feeding from the power transmitting coil 21 . On the other hand, the smaller the proportion of the entire power receiving coil 31 that is housed in the wheels 6, the longer the magnetic field generated by the power transmitting coil 21 reaches the power receiving coil 31 during power feeding from the power transmitting coil 21. hard to attenuate.
[0032]
The power receiving device 3 is not limited to the hub portion 622 of the wheel 62 and may be installed at any position on the wheel 6 . The power receiving device 3 may be installed, for example, on the inner peripheral surface of the rim portion 621 of the wheel 62 or the outer peripheral surface of the rim portion 621 . Furthermore, the power receiving device 3 may be installed on the inner peripheral surface of the tread portion 613 of the tire 61 or may be installed inside the tread portion 613 of the tire 61 . By installing the power receiving device 3 at a position closer to the ground surface of the tire 61, the distance between the power transmitting device 2 and the power receiving device 3 is shortened while the moving body 5 is traveling on the road 4, further improving power supply efficiency. can be made
[0033]
(Configuration of power transmission device)
Next, the configuration of the power transmission device 2 included in the wireless power supply system 1 according to one embodiment of the present invention will be described with reference to FIGS. 3 and 4. FIG.
[0034]
FIG. 3 shows a functional block diagram schematically showing a configuration example of the power transmission device 2 according to one embodiment of the present invention. As shown in FIG. 3 , the power transmission device 2 includes a power conversion unit 22 , a power storage unit 23 , a detection unit 24 , a communication unit 25 , a storage unit 26 and a control unit 27 in addition to the power transmission coil 21 . The power transmission coil 21, the power conversion unit 22, the power storage unit 23, the detection unit 24, the communication unit 25, the storage unit 26, and the control unit 27 are wired or wirelessly connected to each other via a network such as a LAN (Local Area Network). Connected for communication.
[0035]
The power transmission coil 21 generates an alternating magnetic field. In this embodiment, the power transmission coil 21 is configured in an annular shape as a whole. In this specification, the plane surrounded by the annular power transmission coil 21 is also referred to as a coil surface S1 of the power transmission coil 21 . In other words, the power transmission coil 21 is wound in the in-plane direction of the coil surface S1 so as to form the coil surface S1. The power transmission coil 21 can generate an alternating magnetic field in the direction perpendicular to the power transmission coil 21, that is, in the direction in which the perpendicular to the coil surface S1 extends.
[0036]
FIG. 4 shows a schematic diagram that schematically shows the coil surface S1 of the power transmission coil 21 provided in the power transmission device 2 according to one embodiment of the present invention and its inclination using a cross section in the width direction of the road. . As shown in FIG. 4 , the power transmission device 2 is installed on the road 4 so that the perpendicular to the coil surface S1 of the power transmission coil 21 is inclined with respect to the perpendicular to the road surface in the cross section of the road 4 in the width direction. It is configured. In other words, the coil surface S1 of the power transmission coil 21 is inclined with respect to the road surface in the widthwise cross section of the road 4 when installed on the road 4 . More specifically, when the power transmission device 2 is installed on the road 4, the power transmission coil 21 is arranged such that the vertical line V of the coil surface S1 has an inclination θ1 with respect to the vertical line of the road surface in the cross section of the road 4 in the width direction. In addition, it is supported and fixed to the housing of the power transmission device 2 via the support member 211 . The inclination θ1 may be set to an arbitrary angle within a range in which the normal to the coil surface S1 of the power transmission coil 21 is not parallel to the normal to the road surface. At least part of the support member 211 and the housing of the power transmission device 2 may be made of the non-magnetic material described above. This makes it difficult for the magnetic field generated by the power transmission coil 21 to attenuate when passing through the support member 211 and the housing of the power transmission device 2 .
[0037]
　Referring to FIG. 3 again, the power conversion unit 22 is connected to the power transmission coil 21. The power converter 22 includes, for example, an AC/DC converter and an inverter. The power conversion unit 22 converts power transmitted from the power source P or the power storage unit 23 outside the power transmission device 2 and transmits the converted power to the power transmission coil 21 .
[0038]
The electricity storage unit 23 is connected to the power conversion unit 22 . The power storage unit 23 includes, for example, a chargeable/dischargeable storage battery such as a lead storage battery, a nickel hydrogen storage battery, a lithium ion battery, and a sodium sulfur battery. Power storage unit 23 is not limited to a storage battery, and may include a capacitor or the like. The power storage unit 23 stores power transmitted from the power source P via the power conversion unit 22 or transmits power to the power transmission coil 21 .
[0039]
The detection unit 24 includes sensors such as infrared sensors, image sensors, motion sensors, and pressure sensors. The detection unit 24 detects that the power receiving device 3 exists at a position where power can be received from the power transmitting device 2 .
[0040]
The communication unit 25 includes one or more communication modules. The communication module is, for example, a wired LAN communication module, a wireless LAN communication module, a CAN (Controller Area Network) communication module, or the like. The communication unit 25 realizes communication with an external computer or the like via a network such as the Internet.
[0041]
The storage unit 26 is, for example, a semiconductor memory, a magnetic memory, an optical memory, or the like. The storage unit 26 functions, for example, as a main storage device, an auxiliary storage device, or a cache memory. The storage unit 26 stores arbitrary information used for the operation of the power transmission device 2 . For example, the storage unit 26 stores system programs, application programs, embedded software, and the like.
[0042]
The control unit 27 includes one or more processors. The processor may be, for example, a general-purpose processor such as a CPU (Central Processing Unit), or a dedicated processor specialized for specific processing. The controller 27 is not limited to a processor, and may include one or more dedicated circuits. The dedicated circuit may be, for example, an FPGA (Field-Programmable Gate Array) or an ASIC (Application Specific Integrated Circuit). The control unit 27 realizes the functions of the power transmission device 2 by controlling the power transmission coil 21 , the power conversion unit 22 , the power storage unit 23 , the detection unit 24 , the communication unit 25 , and the storage unit 26 described above.
[0043]
The control unit 27 can determine whether or not the power receiving device 3 is in a position where power can be received from the power transmitting device 2 . Specifically, the control unit 27 detects the power receiving device 3 using the detecting unit 24 and determines that the power receiving device 3 is present at a position where power can be received from the power transmitting device 2 . The control unit 27 may indirectly determine that the power receiving device 3 exists at a position where power can be received from the power transmitting device 2 by detecting the moving body 5 or the wheels 6 with the detection unit 24 . Alternatively, the control unit 27 may acquire information from the power receiving device 3 or an external computer via the communication unit 25 indicating that the power receiving device 3 is at a position where power can be received from the power transmitting device 2 .
[0044]
When the control unit 27 determines that the power receiving device 3 is in a position where it can receive power from the power transmitting device 2, it can wirelessly transmit power. Specifically, the control unit 27 controls at least one of the power transmission coil 21, the power conversion unit 22, and the power storage unit 23 to generate an alternating magnetic field in the direction in which the perpendicular to the coil surface S1 of the power transmission coil 21 extends. can be generated.
[0045]
(Configuration of power receiving device)
Next, the configuration of the power receiving device 3 included in the wireless power supply system 1 according to one embodiment of the present invention will be described with reference to FIGS. 5 and 6. FIG.
[0046]
FIG. 5 shows a functional block diagram schematically showing a configuration example of the power receiving device 3 according to one embodiment of the present invention. As shown in FIG. 5 , the power receiving device 3 includes a power conversion unit 32 , a power storage unit 33 , a detection unit 34 , a communication unit 35 , a storage unit 36 ​​, and a control unit 37 in addition to the power reception coil 31 . The power receiving coil 31, the power conversion unit 32, the power storage unit 33, the detection unit 34, the communication unit 35, the storage unit 36, and the control unit 37 are communicably connected to each other by wire or wirelessly via a network such as CAN. ing.
[0047]
The power receiving coil 31 receives power wirelessly. In this embodiment, the receiving coil 31 is configured in a ring as a whole. In this specification, the plane surrounded by the annular power receiving coil 31 is also referred to as a coil surface S2 of the power receiving coil 31 . In other words, the power receiving coil 31 is wound in the in-plane direction of the coil surface S2 so as to form the coil surface S2. In the power receiving coil 31, an electromotive force is generated by electromagnetic induction due to a change in the AC magnetic field penetrating the coil surface S2 generated by the power transmitting coil 21 and the like, and a current flows.
[0048]
FIG. 6 shows a schematic diagram schematically showing the coil surface S2 of the power receiving coil 31 provided in the power receiving device 3 according to one embodiment of the present invention and its inclination. As shown in FIG. 6 , the power receiving device 3 is arranged in a cross section in the width direction of the moving body 5 with at least part of the power receiving coil 31 accommodated in the wheels 6 of the moving body 5 .In addition, the perpendicular to the coil surface S2 of the power receiving coil 31 is configured to be inclined with respect to the perpendicular to the contact surface of the wheel 6 with the road surface. In other words, the coil surface S2 of the power receiving coil 31 is in contact with the road surface of the wheels 6 in the cross section in the width direction of the mobile body 5 in a state where at least part of the power receiving coil 31 is housed in the wheels 6 of the mobile body 5. slanted with respect to the ground. More specifically, the power receiving coil 31 is in a state in which at least part of the power receiving coil 31 is accommodated in the wheels 6 of the mobile body 5, and in the cross section in the width direction of the mobile body 5, the power receiving coil 31 is perpendicular to the coil surface S2 of the power receiving coil 31. is fixed to the housing of the power receiving device 3 via the support member 311 so as to have an inclination θ2 with respect to the perpendicular line of the ground contact surface of the wheel 6 with the road surface. As a result, while the moving object 5 is traveling on the road 4, the coil surface S2 of the power receiving coil 31 faces the coil surface S1 of the power transmitting coil 21, whereby wireless power is supplied from the power transmitting coil 21 to the power receiving coil 31 by electromagnetic induction. done. The inclination θ2 may be set to any angle according to the application of the power receiving device 3, the amount of power to be received, and the like. At least part of the supporting member 311 and the housing of the power receiving device 3 may be formed of the non-magnetic material described above. This makes it difficult for the magnetic field generated by the power transmission coil 21 to attenuate when passing through the support member 311 and the housing of the power receiving device 3 .
[0049]
Here, in this specification, for example, (at least a part of) the surface A "facing" the surface B means that the area in which the surface B extends in the vertical direction of the surface B (in other words, , within a columnar region having a cross section of surface B) (at least a part of surface A) overlaps.
[0050]
　Referring to FIG. 5 again, the power converter 32 is connected to the power receiving coil 31. The power converter 32 includes, for example, an AC/DC converter and an inverter. The power converter 32 transmits the power generated in the power receiving coil 31 to the vehicle-mounted device 51 mounted on the mobile object 5 .
[0051]
The in-vehicle device 51 is, for example, a motor. In this case, the in-vehicle device 51 , which is a motor, consumes the power transmitted from the power receiving device 3 to drive the wheels 6 . More specifically, in this embodiment, the in-vehicle device 51 is an in-wheel motor mounted on the wheel 6 . However, the in-vehicle device 51 may be an onboard motor that is mounted on the main body of the mobile body 5 and drives the wheels 6 by rotating the shaft 52 of the mobile body 5 .
[0052]
The in-vehicle device 51 is not limited to a motor, and may include any electronic device installed in the mobile object 5, such as a storage battery, communication device, car navigation system, media player, and in-vehicle sensor.
[0053]
The electricity storage unit 33 is connected to the power conversion unit 32 . The power storage unit 33 includes, for example, a chargeable/dischargeable battery such as a lead storage battery, a nickel hydrogen storage battery, a lithium ion battery, and a sodium sulfur battery. Power storage unit 33 is not limited to a storage battery, and may include a capacitor. When the power storage unit 33 includes a capacitor, charging and discharging can be performed in a short time compared to a storage battery or the like, which is advantageous in situations where high responsiveness is required. The power storage unit 33 stores power transmitted from the power receiving coil 31 via the power conversion unit 32 , or transmits power to the in-vehicle device 51 .
[0054]
The detection unit 34 includes sensors such as voltage sensors and current sensors. The detection unit 34 detects power wirelessly received by the power receiving coil 31 .
[0055]
The communication unit 35 includes one or more communication modules. The communication module is, for example, a wired LAN communication module, a wireless LAN communication module, a CAN communication module, or the like. The communication unit 35 communicates with an external computer including the power transmission device 2 or the in-vehicle device 51 of the moving body 5 or the like via a network such as the Internet.
[0056]
The storage unit 36 ​​is, for example, a semiconductor memory, a magnetic memory, an optical memory, or the like. The storage unit 36 ​​functions, for example, as a main storage device, an auxiliary storage device, or a cache memory. The storage unit 36 ​​stores arbitrary information used for the operation of the power receiving device 3 . For example, the storage unit 36 ​​stores system programs, application programs, embedded software, and the like.
[0057]
The control unit 37 includes one or more processors. The processor may be, for example, a general-purpose processor such as a CPU, or a dedicated processor specialized for specific processing. The controller 37 is not limited to a processor, and may include one or more dedicated circuits. A dedicated circuit may be, for example, an FPGA or an ASIC. The control unit 37 controls the power receiving coil 31 , the power conversion unit 32 , the power storage unit 33 , the detection unit 34 , the communication unit 35 , and the storage unit 36 ​​described above, and realizes the functions of the power receiving device 3 .
[0058]
The control unit 37 can measure the power wirelessly received by the power receiving device 3 . Specifically, based on the information detected by the detection unit 34 , the control unit 37 measures the intensity of the power wirelessly received by the power reception coil 31 . The intensity of power may be represented by any numerical information, such as power, energy, voltage, current, magnetic flux, or magnetic flux density.
[0059]
The control unit 37 can transmit power wirelessly received by the power receiving device 3 to the in-vehicle device 51 mounted on the mobile object 5 . Specifically, the control unit 37 can transmit power generated in the power receiving coil 31 to the in-vehicle device 51 from the power receiving coil 31 . Alternatively, the control unit 37 may store the power generated in the power receiving coil 31 in the power storage unit 33 and then transmit the power from the power storage unit 33 to the in-vehicle device 51 .
[0060]
(Example of installing a power transmission device on a road)
An example of installation of the power transmission device 2 in the wireless power supply system 1 on the road 4 will be described below with reference to FIGS. 1 and 7. FIG. FIG. 7 is a schematic diagram showing an installation example of a power transmission device on a road in the wireless power supply system according to one embodiment of the present invention. FIG. 7 is a perspective view of the wireless power feeding system 1 shown in FIG.
[0061]
In this embodiment, the wireless power supply system 1 includes a plurality of power transmission devices 2 . As shown in FIG. 7 , a plurality of power transmission devices 2 are installed side by side along the extending direction of the road 4 . Furthermore, at least one pair of power transmission devices 2 is installed in the width direction of the driving lane 41 of the road 4 . As shown in FIG. 7 , in this embodiment, a pair of power transmission devices 2 arranged in the width direction of the travel lane 41 are arranged side by side in the extending direction of the road 4 with a predetermined interval D therebetween. The predetermined interval D may be arbitrarily determined.
[0062]
As shown in FIG. 1 , the coil surface S1 of the power transmission coil 21 is inclined vertically upward with respect to the road surface as it goes inward in the width direction of the driving lane 41 in the cross section of the road 4 in the width direction. there is Further, the coil surface S2 of the power receiving coil 31 is inclined upward in the vertical direction with respect to the contact surface of the wheel 6 with the road surface as it goes inward in the width direction of the moving body 5 in the cross section in the width direction of the moving body 5. is doing. Thereby, the wireless power supply system 1 can install the power transmission device 2 so that the wheels 6 do not run above the power transmission device 2 . Therefore, it is possible to reduce the possibility that the wheels 6 run on the upper side of the power transmission device 2 while the mobile body 5 is running on the road 4 and that the power transmission device 2 is damaged by the load from the wheels 6 . Further, the wireless power supply system 1 wirelessly transmits electric power from the inside in the width direction of the moving body 5 to the power receiving coil 31 of the power receiving device 3 partially accommodated in the wheels 6 of the moving body 5 traveling on the road 4. can do. Therefore, the space between the power transmitting coil 21 and the power receiving coil 31 is surrounded by the road surface of the road 4, the moving body 5, and the wheels 6, and obstacles are unlikely to enter the space.
[0063]
A modification of the wireless power supply system 1 will be described below with reference to FIG. FIG. 8 is a schematic diagram schematically showing a modification of the wireless power feeding system according to one embodiment of the present invention using a cross section in the width direction of the wheel.
[0064]
In the modification of the wireless power supply system 1 shown in FIG. 8 , the coil surface S1 of the power transmission coil 21 is vertically downward with respect to the road surface as it goes inward in the width direction of the driving lane 41 in the cross section of the road 4 in the width direction. sloping towards the Furthermore, the coil surface S2 of the power receiving coil 31 is directed downward in the vertical direction with respect to the contact surface of the wheel 6 with the road surface as it goes inward in the width direction of the moving body 5 in the cross section in the width direction of the moving body 5. Inclined. As a result, electric power can be wirelessly transmitted from the outside of the moving body 5 in the width direction to the power receiving device 3 accommodated in the wheel 6 of the moving body 5 traveling on the road 4 . Therefore, it is possible to reduce the possibility that the wheels 6 run on the upper side of the power transmission device 2 while the mobile body 5 is running on the road 4 and that the power transmission device 2 is damaged by the load from the wheels 6 . For example, the power receiving device 3 may be embedded below a partition line indicating the widthwise end of the travel lane 41 of the road 4 .
[0065]
In the wireless power supply system 1 and the modification of the wireless power supply system 1 described above with reference to FIGS. Although the wheel 6 is configured to be inclined with respect to the perpendicular line of the contact surface of the wheel 6 with the road surface, this is not the only option. The coil surface S2 of the power receiving coil 31 may extend substantially parallel to the contact surface of the wheel 6 with the road surface in the cross section of the moving body 5 in the width direction. Accordingly, as shown in FIG. 1 or FIG. 8, the installation position of the power transmission device 2 in the width direction of the road 4 or the inclination of the power transmission coil 21 of the power transmission device 2 installed on the road 4 differs depending on the road 4. In this case, it is possible to reduce variations in power reception efficiency in the power receiving device 3 of the power wirelessly transmitted from the power transmitting device 2 .
[0066]
In this specification, for example, plane A is preferably parallel to plane B when plane A is "substantially parallel" to plane B. However, the plane A does not need to be completely parallel, and the plane A may be inclined to the plane B by about ±5 degrees.
[0067]
As described above, the wireless power feeding system 1 according to one embodiment of the present invention includes the power transmitting device 2 and the power receiving device 3. The power transmission device 2 is a power transmission device 2 installed on the road 4 and includes a power transmission coil 21 that wirelessly transmits power. is configured so that the perpendicular to the coil surface of is inclined with respect to the perpendicular to the road surface of the road 4 . The power receiving device 3 includes a power receiving coil 31 that wirelessly receives power. According to the wireless power supply system 1 having such a configuration, at least part of the power receiving coil 31 is accommodated in the wheel 6 that is in direct contact with the road surface, so that the power transmitting coil 21 provided on the road surface and the power receiving coil 31 are connected. It is possible to reduce the risk of obstacles entering the space between them. Therefore, the wireless power supply system 1 can improve power supply efficiency in wireless power supply. Furthermore, since the normal to the coil surface of the power transmitting coil 21 is inclined with respect to the normal to the road surface, the moving body 5 has the coil surface S2 of the power receiving coil 31 facing the coil surface S1 of the power transmitting coil 21. It is not necessary to run so that the ground surface of the wheels 6 is positioned above the power transmission device 2 . Therefore, while the moving body 5 is traveling on the road 4 , it is possible to reduce the risk that the wheels 6 will run above the power transmission device 2 and that the load from the wheels 6 will damage the power transmission device 2 . Therefore, according to the wireless power supply system 1 according to one embodiment of the present invention, the usefulness of the wireless power supply technology for wirelessly supplying power to the moving body 5 is improved.
[0068]
In the wireless power supply system 1 according to one embodiment of the present invention, the power transmission coil 21 is preferably positioned below the road surface of the road 4 in the vertical direction. According to such a configuration, the wireless power supply system 1 can reduce the possibility that the wheels 6 of the mobile body 5 running on the road 4 will come into contact with the power transmission coil 21 of the power transmission device 2 and damage the power transmission coil 21 . .
[0069]
In the wireless power supply system 1 according to one embodiment of the present invention, at least one driving lane 41 is provided on the road 4, and the coil surface S1 of the power transmission coil 21 is the width of the driving lane 41 in the cross section of the road 4 in the width direction. direction inward It is preferable that the slope is inclined upward in the vertical direction with respect to the road surface as it goes. According to this configuration, in the wireless power supply system 1 , the power transmission device 2 can be installed so that the wheels 6 do not run above the power transmission device 2 . As a result, the wireless power supply system 1 can reduce the risk that the wheels 6 will run above the power transmission device while the mobile body 5 is running on the road 4 and that the power transmission device 2 will be damaged by the load from the wheels 6. can. Further, in the wireless power supply system 1, the power transmission device 2 wirelessly transmits power from the width direction inside of the mobile body 5 to the power receiving device 3 accommodated in the wheel 6 of the mobile body 5 traveling on the road 4. can be done. As a result, the wireless power feeding system 1 can further reduce the risk of an obstacle entering the space between the power transmitting coil 21 and the power receiving coil 31 during power feeding.
[0070]
In the wireless power supply system 1 according to one embodiment of the present invention, at least one driving lane 41 is provided on the road 4, and the coil surface S1 of the power transmission coil 21 is the width of the driving lane 41 in the cross section of the road 4 in the width direction. It is preferable to incline downward in the vertical direction with respect to the road surface as it goes inward. According to this configuration, in the wireless power supply system 1, the power transmission device 2 wirelessly supplies electric power from the width direction outside of the mobile body 5 to the power receiving device 3 accommodated in the wheels 6 of the mobile body 5 traveling on the road 4. can be transmitted. As a result, the wireless power supply system 1 further reduces the possibility that the wheels 6 run above the power transmission device 2 while the mobile body 5 is running on the road 4 and the power transmission device 2 is damaged by the load from the wheels 6. be able to.
[0071]
In the wireless power supply system 1 according to one embodiment of the present invention, it is preferable that a plurality of power transmission devices 2 be installed side by side along the extending direction of the road 4 . According to such a configuration, the wireless power feeding system 1 can wirelessly transmit power from the plurality of power transmitting devices 2 to the power receiving device 3 accommodated in the wheel 6 of the mobile body 5 traveling on the road 4. .
[0072]
In the wireless power supply system 1 according to one embodiment of the present invention, at least one driving lane 41 is provided on the road 4, and at least one pair of power transmission devices 2 is installed in the driving lane 41 in the width direction of the driving lane 41. It is preferable that According to such a configuration, the wireless power supply system 1, when a plurality of wheels 6 are arranged side by side in the width direction of the mobile body 5, such as a four-wheeled vehicle, is attached to each wheel 6. power can be transmitted wirelessly from the power transmission device 2 of the
[0073]
In the wireless power supply system 1 according to one embodiment of the present invention, it is preferable that the power transmission device 2 wirelessly transmits power when the power reception device 3 determines that the power reception device 3 is present at a position capable of receiving power from the power transmission device 2 . . According to such a configuration, the wireless power supply system 1 can reduce the power consumption of the power transmission device 2 by wirelessly transmitting power when the power transmission device 2 is not at a position where the power reception device 3 can receive power. can.
[0074]
In the wireless power supply system 1 according to one embodiment of the present invention, the power receiving device 3 is configured so that the perpendicular to the coil surface S2 of the power receiving coil 31 is aligned with the perpendicular to the ground contact surface of the wheel 6 with the road surface in the cross section in the width direction of the mobile object 5. It is preferably configured so as to be inclined with respect to. According to such a configuration, the wireless power supply system 1 improves the power reception efficiency in the power receiving device 3 of the power transmitted from the power transmitting device 2 in which the perpendicular to the coil surface S1 of the power transmitting coil 21 is inclined with respect to the perpendicular to the road surface. can be done.
[0075]
In the wireless power supply system 1 according to one embodiment of the present invention, the coil surface S2 of the power receiving coil 31 is in contact with the road surface of the wheel 6 as it goes inward in the width direction of the moving body 5 in the cross section in the width direction of the moving body 5. It is preferably slanted vertically upwards with respect to the ground. According to such a configuration, the wireless power feeding system 1 can improve the power receiving efficiency of the power receiving device 3 of the power wirelessly transmitted from the inside of the moving body 5 in the width direction to the power receiving device 3 of the moving body 5 . .
[0076]
In the wireless power supply system 1 according to one embodiment of the present invention, the coil surface S2 of the power receiving coil 31 is in contact with the road surface of the wheel 6 as it goes inward in the width direction of the moving body 5 in the cross section in the width direction of the moving body 5. It is preferably slanted vertically downwards with respect to the ground. According to such a configuration, the wireless power supply system 1 can improve the power reception efficiency of the power receiving device 3 of the power wirelessly transmitted from the outside in the width direction of the moving body 5 to the power receiving device 3 of the moving body 5 . .
[0077]
In the wireless power supply system 1 according to one embodiment of the present invention, the coil surface of the power receiving coil 31 extends substantially parallel to the contact surface of the wheel 6 with the road surface in the cross section in the width direction of the moving body 5. preferable. According to this configuration, the wireless power supply system 1 can be set to the power transmission device 2 when the installation position of the power transmission device 2 in the width direction of the road 4 or the inclination of the power transmission coil 21 of the power transmission device 2 installed on the road 4 is different. It is possible to reduce variations in power reception efficiency in the power receiving device 3 of power wirelessly transmitted from the power receiving device 3 .
[0078]
In the wireless power supply system 1 according to one embodiment of the present invention, the wheel 6 is preferably a tire/wheel assembly consisting of a tire 61 and a wheel 62 . According to such a configuration, in the wireless power supply system 1, the space inside the wheel 6 is separated from the outside of the wheel 6 by the tire 61 and the wheel 62, so that the space between the power transmitting coil 21 and the power receiving coil 31 is free of obstacles. can be reduced.
[0079]
A power transmission device 2 according to an embodiment of the present invention includes a power transmission coil 21 that wirelessly transmits power. It is configured such that the perpendicular is inclined with respect to the perpendicular to the road surface of the road 4 . According to such a configuration, the power transmission device 2 can wirelessly transmit power while the mobile body 5 equipped with the power reception device 3 is traveling on the road 4 . Furthermore, the power transmission device 2 reduces the possibility that the wheels 6 of the mobile body 5 run above the power transmission device 2 and the power transmission device 2 is damaged by the load from the wheels 6 while the mobile body 5 is running on the road 4. can be made Therefore, according to the power transmission device 2 according to one embodiment of the present invention, the usefulness of the wireless power supply technology for wirelessly supplying power to the moving object 5 is improved.
[0080]
A power receiving device 3 according to an embodiment of the present invention includes a power receiving coil 31 that wirelessly receives power. In the cross section in the width direction, the perpendicular to the coil surface S2 of the power receiving coil 31 is configured to be inclined with respect to the perpendicular to the contact surface of the wheel 6 with the road surface. According to such a configuration, the power receiving device 3 can wirelessly receive power from the power transmitting device 2 installed on the road 4 while the mobile object 5 is traveling on the road 4 . As a result, the power receiving device 3 can receive electric power for driving the mobile body 5 from the outside of the mobile body 5, so that the size and weight of the storage battery installed in the mobile body 5 can be reduced. It enables the fuel efficiency of the body 5 to be improved. Therefore, according to the power receiving device 3 according to the embodiment of the present invention, the usefulness of the wireless power supply technology for wirelessly supplying power to the moving body 5 is improved.
[0081]
Although the present invention has been described based on the drawings and embodiments, it should be noted that a person skilled in the art can make various modifications and modifications based on the present invention. Therefore, it should be noted that these variations and modifications are included within the scope of the present invention. For example, configurations or functions included in each embodiment or each example can be rearranged so as not to be logically inconsistent. In addition, the configurations or functions included in each embodiment can be used in combination with other embodiments or other examples, and multiple configurations or functions can be combined into one, divided, or combined into one. It is possible to omit the part.
[0082]
For example, in the above-described embodiments, all or part of the functions or processes described as the functions or processes of the control unit 27 of the power transmission device 2 or the control unit 37 of the power reception device 3 are It may be implemented as a computer function or process. Specifically, a program describing processing details for realizing each function of the control unit 27 of the power transmitting device 2 or the control unit 37 of the power receiving device 3 according to the present embodiment is stored in the memory of the computer, and the processor of the computer The program can be read and executed. Therefore, the invention according to this embodiment can also be implemented as a program executable by a processor. For example, a control device (ECU: Electronic Control Unit) of the moving body 5 may be configured to function as the control unit 37 of the power receiving device 3 .
[0083]
Furthermore, in the above-described embodiment, the power transmitting device 2 and the power receiving device 3 are configured such that part or all of the operations and processes performed by the control unit 27 of the power transmitting device 2 are performed by the control unit 37 of the power receiving device 3. may For example, when the mobile object 5 travels on the road 4 on which the power transmission device 2 is installed, the control unit 37 of the power reception device 3 controls the power transmission device 2 to cause the power transmission device 2 to wirelessly transmit power. good.
[0084]
Also, for example, in the embodiment described above, the tire 61 was described as being filled with air, but this is not the only option. For example, tire 61 can be filled with a gas such as nitrogen. Also, for example, the tire 61 can be filled with any fluid, including liquid, gel-like substance, powder, or the like, instead of or in addition to gas.
Code explanation
[0085]
1: wireless power supply system, 2: power transmission device, 21: power transmission coil, 211: support member, 22: power conversion unit, 23: power storage unit, 24: detection unit, 25: communication unit, 26: storage unit, 27: control Unit 3: power receiving device 31: power receiving coil 311: support member 32: power conversion unit 33: power storage unit 34: detection unit 35: communication unit 36: storage unit 37: control unit 4: Road, 41: Driving lane, 5: Mobile body, 51: In-vehicle device, 52: Shaft, 6: Wheel, 61: Tire, 611: Bead portion, 612: Sidewall portion, 613: Tread portion, 62: Wheel, 621 : Rim part, 622: Hub part, 623: Disk part, P: Power source, S1, S2: Coil surface, θ1, θ2: Inclination, V: Vertical direction
The scope of the claims
[Claim 1]
A power transmission device installed on a road, comprising a power transmission coil that wirelessly transmits power, and in a state of being installed on the road, in a cross section in the width direction of the road, a perpendicular line to a coil surface of the power transmission coil is the road. a power transmission device configured to be inclined with respect to the normal to the road surface of the
a power receiving device comprising a power receiving coil that wirelessly receives power, at least part of the power receiving coil being housed in a wheel of a mobile body;
A wireless power supply system, including:
[Claim 2]
The wireless power supply system according to claim 1, wherein the power transmission coil is located vertically below the road surface of the road.
[Claim 3]
At least one driving lane is provided on the road,
3. According to claim 1 or 2, the coil surface of the power transmission coil is inclined upward in the vertical direction with respect to the road surface as it goes inward in the width direction of the driving lane in the cross section of the road in the width direction. The wireless power supply system described.
[Claim 4]
At least one driving lane is provided on the road,
3. The coil surface of the power transmission coil is inclined downward in the vertical direction with respect to the road surface as it goes inward in the width direction of the driving lane in a cross section of the road in the width direction. The wireless power supply system according to .
[Claim 5]
The wireless power supply system according to any one of claims 1 to 4, wherein a plurality of said power transmission devices are installed side by side along the extension direction of said road.
[Claim 6]
At least one driving lane is provided on the road,
The driving lane according to any one of claims 1 to 5, wherein at least one pair of the power transmission devices is installed in the width direction of the driving lane.Wireless power supply system.
[Claim 7]
The wireless power supply according to any one of claims 1 to 6, wherein the power transmission device transmits power wirelessly when it is determined that the power reception device is present at a position where the power can be received from the power transmission device. system.
[Claim 8]
2. The power receiving device is configured such that a perpendicular to a coil surface of the power receiving coil is inclined with respect to a perpendicular to a ground contact surface of the wheel with the road surface in a cross section in the width direction of the moving body. 8. The wireless power supply system according to any one of 7.
[Claim 9]
The coil surface of the power receiving coil is inclined upward in the vertical direction with respect to the contact surface of the wheel with the road surface as it goes inward in the width direction of the vehicle in the cross section in the width direction of the vehicle. The wireless power supply system according to claim 8, wherein
[Claim 10]
The coil surface of the power receiving coil is slanted downward in the vertical direction with respect to the contact surface of the wheel with the road surface as it goes inward in the width direction of the vehicle in the cross section in the width direction of the vehicle. 10. The wireless power supply system according to claim 9, wherein the
[Claim 11]
The radio according to any one of claims 1 to 7, wherein a coil surface of the power receiving coil extends substantially parallel to a contact surface of the wheel with the road surface in a cross section in the width direction of the moving body. power supply system.
[Claim 12]
The wireless power supply system according to any one of claims 1 to 11, wherein the wheel is a tire-wheel assembly consisting of a tire and a wheel.
[Claim 13]
Equipped with a power transmission coil that transmits power wirelessly,
A power transmission device that is installed on a road and configured such that the perpendicular to the coil surface of the power transmission coil is inclined with respect to the perpendicular to the road surface of the road in the cross section in the width direction of the road.
[Claim 14]
Equipped with a receiving coil that receives power wirelessly,
In a state in which at least a part of the power receiving coil is housed in a wheel of the moving body, the perpendicular line of the coil surface of the power receiving coil is aligned with the perpendicular line of the ground contact surface of the wheel with the road surface in the cross section in the width direction of the moving body. A powered device configured to tilt at the