Buried structure and burial method for power supply devices

Abstract

To bury a power supply device for contactlessly supplying power to a power reception device provided on a movable body in the vicinity of a road surface of a driving lane having asphalt pavement by achieving high workability and adhesiveness.SOLUTION: In a power supply device burying structure, a power supply device for contactlessly supplying power to a power reception device provided on a movable body moving on a driving lane is buried in the driving lane. The power supply device has a power supply coil and a coil case to store the power supply coil and is formed by burying the coil case in a pavement of the driving lane constructed by curing asphalt mixture. Intermediate members for forming a rough surface are provided on a surface of the coil case.SELECTED DRAWING: Figure 1

Description

Technical Field

[0006] , , ,

[0001] The present invention relates to a buried structure of a power feeding device and a method of burying the power feeding device for burying a power feeding device that non - contact - feeds power to a power receiving device provided on a moving body in a traveling path.

Background Art

[0002] Conventionally, research and development on wireless power transmission that performs non - contact power transmission by utilizing the magnetic field resonance phenomenon (magnetic field resonance phenomenon) occurring between a power feeding device and a power receiving device has been promoted.

[0003] For example, Patent Document 1 discloses a configuration in which a non - contact power supply device including power receiving resonance means and power feeding resonance means is provided with frequency variable means for setting the frequency of alternating current power according to the value of impedance viewed from the power feeding side within a predetermined frequency range. Thereby, even if the coupling state between the power receiving resonance means and the power feeding resonance means changes, a frequency with higher power transmission efficiency can be set, and a decrease in power transmission efficiency can be suppressed.

[0004] Such technologies are utilized in various fields, and among them, in particular, it is expected to be used in a traveling - in - motion power supply system that supplies power to a vehicle in motion. The traveling - in - motion power supply system provides a power feeding coil included in the power feeding device and a resonance capacitor connected in series with this power feeding coil on the road side, while providing a power receiving device including a power receiving coil on the vehicle side. Thereby, it is intended to supply power to a vehicle in motion non - contact, continuously or intermittently.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] As described above, if power supply equipment can be buried along the roadside to enable wireless power supply, it will be possible to address the challenges of electric vehicles, such as short driving range and long charging times. This will encourage the use of electric vehicles and contribute to reducing carbon dioxide emissions from transportation.

[0007] Generally, a power supply device consists of a power supply coil that transmits high-frequency power, housed in a coil case, and buried in the roadway. When burying a power supply device in the roadway, it is preferable to bury it at a shallow depth near the road surface, i.e., in the pavement, considering power transmission efficiency.

[0008] However, the coil case is not manufactured with consideration for adhesion to the pavement. Therefore, if vertical loads from electric vehicles and other sources are repeatedly transmitted over a long period of time, problems such as rattling may occur. In addition, when asphalt pavement is used, the construction process includes the work of pouring asphalt mixture exceeding 200°C onto the roadbed. Therefore, if the construction work of the asphalt pavement and the work of embedding the power supply device in the asphalt pavement are carried out simultaneously, the power supply device may be exposed to a high temperature environment exceeding 200°C and may be damaged.

[0009] The present invention has been made in view of the above problems, and its main objective is to embed a power supply device, which supplies power to a power receiving device installed on a mobile body without contact, near the road surface of a road with asphalt pavement, with high workability and adhesion. [Means for solving the problem]

[0010] To achieve this objective, the buried power supply device structure of the present invention is a buried power supply device structure for which a power supply device that provides non-contact power to a power receiving device provided on a mobile body is buried in a travel path, wherein the power supply device comprises a power supply coil and a coil case that houses the power supply coil, and the coil case teeth, Embedding in the pavement of the aforementioned road, which is constructed by hardening an asphalt mixture. At the same time, surface The intermediate member is formed to create a rough surface, and the intermediate member is made of a material with low thermal conductivity or high heat capacity that can block or delay the conduction of heat from the asphalt mixture before it hardens between it and the coil case during the construction of the pavement, and is attached to the coil case via a fixing means, thereby forming a rough surface on the surface of the coil case. It is characterized by the following:

[0011] The buried structure of the power supply device of the present invention is A power supply device is embedded in a roadway to provide contactless power to a power receiving device installed on a mobile body, wherein the power supply device comprises a power supply coil and a coil case housing the power supply coil, and the coil case is embedded in the pavement of the roadway constructed by hardening an asphalt mixture, and its surface is formed into a rough surface using an intermediate member. The intermediate member It is a three-dimensional reticular structure. It is characterized by the following:

[0012] The buried structure of the power supply device of the present invention is A power supply device is embedded in a roadway to provide contactless power to a power receiving device installed on a mobile body, wherein the power supply device comprises a power supply coil and a coil case housing the power supply coil, and the coil case is embedded in the pavement of the roadway constructed by hardening an asphalt mixture, and its surface is formed into a rough surface using an intermediate member. The intermediate member These are multiple pieces of wood. It is characterized by the following:

[0013] The buried structure for the power supply device of the present invention is characterized in that the pavement is a semi-flexible pavement.

[0014] The buried structure of the power supply device of the present invention is characterized in that the travel path is a road.

[0015] The present invention relates to a method for burying a power supply device, which is a method for burying a power supply device for constructing a buried structure for the power supply device of the present invention, characterized in that the asphalt mixture is poured and the coil case is buried in the asphalt mixture.

[0016] According to the embedded structure and method for the power supply device of the present invention, a rough surface made of an intermediate member is formed on the coil case housing the power supply coil, thereby improving adhesion with the asphalt pavement that constitutes the roadway. Therefore, even if vertical loads such as those from moving objects are repeatedly transmitted to the coil case, rattling will not occur, and it will be possible to embed the device stably near the road surface of the asphalt pavement for a long period of time.

[0017] Furthermore, as an intermediate member, a material with thermal conductivity or heat capacity capable of blocking or delaying the conduction of heat from the asphalt mixture between it and the coil case during the construction of the pavement, a three-dimensional mesh with an air layer, or wood chips are used. As a result, the heat conduction from the asphalt mixture, which exceeds 200°C during placement, to the coil case is reduced by the intermediate member. This prevents the coil case and the power supply coil housed within it, which are vulnerable to high temperatures, from being exposed to a high-temperature environment. [Effects of the Invention]

[0018] According to the present invention, it is possible to embed a power supply device of a power supply system during travel, which continuously or intermittently supplies power to a moving body during travel, near the road surface of an asphalt pavement with high workability and adhesion.

Brief Description of the Drawings

[0019] [Figure 1] It is a diagram showing an embedding structure and method of a power supply device in an embodiment of the present invention (First Embodiment). [Figure 2] It is a diagram showing an outline of a power supply device in an embodiment of the present invention (First Embodiment). [Figure 3] It is a diagram showing an embedding structure and method of a power supply device in an embodiment of the present invention (Second Embodiment). [Figure 4] It is a diagram showing an embedding structure and method of a power supply device in an embodiment of the present invention (Third Embodiment). [Figure 5] It is a diagram showing an embedding structure and method of a power supply device in an embodiment of the present invention (Fourth Embodiment).

Modes for Carrying Out the Invention

[0020] The present invention relates to an embedding structure when embedding a power supply device constituting a power supply system during travel in a road surface, and is particularly suitable for embedding in a pavement constructed by curing an asphalt mixture such as an asphalt pavement layer or a semi-flexible pavement.

[0021] The moving body that moves using the power supply system during travel is not particularly limited as long as it is an electric vehicle that drives a motor by electric power. Also, the road surface where the power supply device is to be embedded may be any as long as it has a structure capable of providing asphalt pavement, such as a general road, a highway, a parking lot, or a roadway provided in a factory site.

[0022] In this embodiment, the buried structure and method of the power supply device will be explained in detail with reference to Figures 1 to 5, using the case where the travel path is a road as an example. Before explaining the buried structure of the power supply device, the in-vehicle power supply system will be explained first.

[0023] <<<<On-Driving Power Supply System 100>>>> As shown in Figures 1(a) and (b), the in-driving power supply system 100 includes a power receiving device 20 mounted on the electric vehicle V and a power supply device 10 embedded in the asphalt pavement layer 31 of the road 30, which is made of hardened asphalt mixture 311.

[0024] The power supply device 10 comprises a power supply coil 11 housed in a coil case 13 and a power supply device 12 connected to the power supply coil 11. The power supply device 12 generates high-frequency power. The generated high-frequency power is output to the power supply coil 11. On the other hand, the power receiving device 20 comprises a power receiving coil 21 and a load 22. The load 22 is connected to the power receiving coil 21, and the power receiving coil 21 is connected in series with a resonant capacitor (not shown) provided on the V side of the electric vehicle to form a series resonant circuit.

[0025] As a result, the receiving coil 21 and the supplying coil 11 are magnetically coupled by magnetic field resonance, and high-frequency power is transmitted from the power supply device 10 to the receiving coil 21. The transmitted high-frequency power is supplied to the load 22 of the electric vehicle V. In this way, the in-driving power supply system 100 can wirelessly supply power from the power supply device 10 embedded in the asphalt pavement layer 31 to the receiving device 20 mounted on the electric vehicle V.

[0026] <<<Underground Structure of Power Supply Equipment>>> In the above-described in-driving power supply system 100, the power supply coil 11 of the power supply device 10 is housed in a coil case 13 as shown in Figure 2(a) and embedded in the asphalt pavement layer 31 of the road 30.

[0027] The coil case 13 is made of an impact-resistant material (for example, polycarbonate, polypropylene, or hard rubber). Furthermore, a structure to enhance waterproofing is provided throughout the entire coil case 13, including the outlet portion of the wires forming the power supply coil 11. In addition, as shown in Figure 2(b), the coil case 13 is provided with a plurality of intermediate members 14 on the surface facing the asphalt pavement layer 31.

[0028] The intermediate member 14 is made of a material that can form a rough surface on the coil case 13 and has low thermal conductivity or high heat capacity. The thermal conductivity or heat capacity should preferably be such that it can block or delay the conduction of heat from the asphalt mixture 311 between the coil case 13 and the asphalt pavement layer 31 during construction, as shown in Figure 1(a). Specifically, concrete pieces and crushed stone can be given as examples of intermediate members 14. These can be attached to the coil case 13 using appropriate fixing means such as adhesive.

[0029] As shown in Figure 1(b), the asphalt mixture 311 that forms the asphalt pavement layer 31 upon hardening can be any type used for road paving, such as a hot-mix asphalt mixture or a room-temperature hot-mix asphalt mixture.

[0030] ≪First Embodiment≫ Considering power transmission efficiency, it is preferable to embed the coil case 13 of the power supply device 10 having the above configuration near the road surface 33 of the road 30. For this reason, Figures 1(a) and (b) illustrate a case in which the coil case 13 is embedded in the asphalt pavement layer 31 in such a way that it is continuous with the road surface 33, with the upper surface covered with a cover material C or the like. The procedure for embedding the power supply device 10 in the asphalt pavement layer 31 in this manner is as follows.

[0031] As shown in Figure 1(b), a high-temperature asphalt mixture 311 is poured onto the roadbed 32, and the coil case 13 is embedded in the asphalt mixture 311. The coil case 13 is positioned at approximately the same height as the road surface 33 of the road 30. In addition, the asphalt mixture 311 is subjected to the same work necessary for road construction as in general road construction, such as spreading and compaction. After this, the asphalt mixture 311 is allowed to cure until it hardens, and then the coil case 13 is covered with a cover material C made of an elastic material such as rubber as appropriate.

[0032] As mentioned above, the coil case 13 is provided with multiple intermediate members 14 on its side circumferential surface and bottom surface facing the asphalt mixture 311. Therefore, although heat from the asphalt mixture 311 is transferred to the intermediate members 14 during the curing period of the asphalt mixture 311, the low thermal conductivity or high heat capacity of the intermediate members 14 can block or delay heat conduction to the coil case 13. This prevents the coil case 13 and the power supply coil 11 housed therein from being exposed to high-temperature environments.

[0033] Furthermore, as shown in Figure 1(a), once the asphalt mixture 311 hardens and the asphalt pavement layer 31 is constructed, the coil case 13, whose surface is roughened by the intermediate member 14, adheres tightly to and integrates with the asphalt pavement layer 31.

[0034] This allows the coil case 13 to be embedded stably near the road surface 33 of the asphalt pavement layer 31 over a long period of time without rattling, even when vertical loads such as those from electric vehicles V are repeatedly transmitted to the coil case 13. Such a structure is suitable, for example, for roads 30 with low traffic volume, and the coil case 13 should be manufactured to be robust.

[0035] ≪Second Embodiment≫ On the other hand, on roads with heavy traffic, the entire coil case 13 is embedded in the asphalt pavement layer 31, as shown in Figure 3(a). In this case, the embedding depth of the coil case 13 should be appropriately set to a shallow position that does not significantly affect the power transmission efficiency of the power supply coil 11. The procedure for embedding the power supply device 10 in the asphalt pavement layer 31 is as follows.

[0036] First, as in the first embodiment, as shown in Figure 3(b), the asphalt mixture 311 is poured onto the roadbed 32, and the coil case 13 is embedded in the asphalt mixture 311. The entire coil case 13 is embedded in the asphalt mixture 311. For this reason, the intermediate member 14 is installed not only on the side circumferential surface and bottom surface of the coil case 13, but also on the top surface.

[0037] If the upper surface of the coil case 13 can be stiffened by providing the intermediate member 14 in this way, the thickness of the upper surface of the coil case 13 may be reduced to bring the housed power supply coil 11 closer to the road surface 33. This can also contribute to improving the power transmission efficiency of the power supply device 10.

[0038] In the first and second embodiments described above, a member made of a material that can form a rough surface on the coil case 13 and has low thermal conductivity or high heat capacity was used as the intermediate member 14, but the embodiment is not limited to this. In the third embodiment, a case in which a member having an air layer is used as the intermediate member 14 will be explained as an example.

[0039] ≪Third Embodiment≫ As shown in Figure 4(a), the coil case 13 embedded in the asphalt pavement layer 31 is completely covered with a three-dimensional mesh structure 15. The three-dimensional mesh structure 15 is formed by fusing or linking long fibers of thermoplastic resin in a three-dimensional direction to create a three-dimensional structure. Examples include those formed in a woven manner as shown in Figure 4(b), and those in a nonwoven fabric-like manner in which long fibers are accumulated in one direction or randomly as shown in Figure 4(c). These are all so-called thermoplastic three-dimensional mesh fiber structures that are commonly used as civil engineering materials and have an air layer inside.

[0040] Therefore, as shown in Figure 4(a), by installing the three-dimensional mesh 15 on the coil case 13 using a fixing means such as an adhesive, an insulating layer can be formed surrounding the coil case 13. This allows the three-dimensional mesh 15 to block or delay heat conduction to the coil case 13 during the curing period of the asphalt mixture 311.

[0041] Furthermore, by installing the three-dimensional mesh structure 15 so as to cover the coil case 13, a rough surface can be formed on the surface of the coil case 13. Therefore, adhesion between the asphalt mixture 311 and the asphalt pavement layer 31 after it has hardened can be improved.

[0042] Furthermore, the three-dimensional mesh structure 15 is made of a material whose rebound elasticity can be controlled. Therefore, after the road 30 is put into service, it can efficiently absorb vertical loads such as those from electric vehicles V that are repeatedly transmitted from the road surface 33 to the coil case 13, thereby protecting the power supply coil 11 housed in the coil case 13 from external forces such as shocks and vibrations.

[0043] As an intermediate member having an air layer, in addition to the three-dimensional mesh body 15 described above, other examples include wooden pieces 16 as shown in Figure 5. Furthermore, in the first to third embodiments, an asphalt pavement layer 31 was provided as the pavement for the road 30, but a semi-flexible pavement body 34 may be used instead.

[0044] ≪Fourth Embodiment≫ Figures 5(a) and (b) show a construction method when wooden blocks 16 are used as intermediate members and semi-flexible pavement bodies 34 are used for the pavement of the road 30.

[0045] The semi-flexible pavement 34 is a pavement that has excellent resistance to plastic deformation and can suppress the occurrence of rutting. As shown in Figure 5(b), it is constructed by impregnating cement milk 342 into the voids of a high-temperature open-graded asphalt mixture 341.

[0046] On the other hand, the wood chips 16 have insulating properties because they are made of a material that contains air. Also, as is known from combustion design methods, when the wood chips 16 are exposed to high temperatures, a carbonized layer forms on their outer surface, making it difficult for heat to penetrate to the interior. Furthermore, once the carbonized layer is formed, the oxygen necessary for combustion is not supplied to the interior of the wood chips 16, thus suppressing the progress of combustion.

[0047] Therefore, in Figure 5(a), a high-temperature open-graded asphalt mixture 341 is poured into the roadbed 32, and a coil case 13 is embedded in this open-graded asphalt mixture 341. Wooden pieces 16 are attached to the entire surface of the coil case 13 via a fixing means such as adhesive. As described above, even when the wooden pieces 16 come into contact with the high-temperature open-graded asphalt mixture 341, only a carbonized layer is formed on the surface and they do not burn.

[0048] Furthermore, during the curing period of the asphalt mixture 311, the insulating effect of the air layer between the carbonized layer and the wood chips 16 can block or delay heat conduction to the coil case 13. This prevents the coil case 13 and the power supply coil 11 housed therein from being exposed to high-temperature environments.

[0049] Once the open-graded asphalt mixture 341 has hardened and its temperature has decreased, cement milk 342 is permeated into the voids of the open-graded asphalt mixture 341, as shown in Figure 5(b). This constructs the semi-flexible pavement 34. The cement milk 342 also fills the gaps between the wood chips 16 and the open-graded asphalt mixture 341. Therefore, the semi-flexible pavement 34 and the coil case 13 can be integrated.

[0050] In this way, by embedding the coil case 13 in the semi-flexible pavement 34, rutting of the road surface 33 becomes less likely even when the road 30 is in service for a long period of time. As a result, as shown in Figure 1, it is possible to avoid large changes over time in the distance L between the power receiving coil 21 mounted on the electric vehicle V traveling on the road surface 33 and the coil case 13, that is, the distance to the power supply coil 11 housed in the coil case 13. Therefore, the embedded structure of the power supply device 10 can maintain stable power transmission efficiency over a long period of time.

[0051] The buried structure for a power supply device and the buried method for a power supply device of the present invention are not limited to the embodiments described above, and it goes without saying that various modifications are possible without departing from the spirit of the present invention.

[0052] Furthermore, while this embodiment illustrates a case where only the power supply coil is housed in the coil case, it is not limited to this. Other equipment used in the power supply system (such as resonant capacitors) may also be housed in the coil case together with the power supply coil. Moreover, other equipment used in the power supply system may be housed independently.

[0053] Furthermore, there are no restrictions whatsoever on the mixing ratio of aggregate and asphalt binder, or the void ratio, of the asphalt mixture 311 that constitutes the asphalt pavement layer 31. Also, the asphalt mixture 311 may be poured in multiple layers or in a single layer.

[0054] Similarly, the open-graded asphalt mixture 341 constituting the semi-flexible pavement 34 is not limited in any way in terms of the mixing ratio of aggregates and asphalt binders, or the void ratio. Furthermore, any type of cement milk 342 can be used as long as it is a material used in the asphalt pavement layer 31.

[0055] Therefore, by adopting cement milk 342, which uses low-carbon cement as its main ingredient and can significantly reduce CO2 emissions, it becomes possible to create an environmentally friendly structure for the buried power supply device 10 using the semi-flexible pavement 34.

[0056] Furthermore, in this embodiment, a fully permeable type in which cement milk 312 permeates the entire semi-flexible pavement 34 is exemplified, but it is not limited to this, and a semi-permeable type in which only the upper half permeates may also be used.

[0057] Furthermore, regarding the power supply coil 11 that constitutes the power supply system 100 while driving, this embodiment uses a "magnetic field coupling method" as an example, but it is also possible to adopt an "electrolytic coupling method".

[0058] Furthermore, in this embodiment, examples were given of intermediate members having an air layer, such as a three-dimensional mesh 15 or a piece of wood 16, but the embodiment is not limited to these, and a member with a vacuum layer may also be used. [Explanation of symbols]

[0059] 100 In-Driving Power Supply System 10 Power supply device 11 Power supply coil 12 Power supply 13 Coil Cases 14 Intermediate members 15. Three-dimensional mesh structure (intermediate member) 16. Wooden pieces (intermediate members) 20 Power receiving equipment 21 Power receiving coil 22 load 30 road 31. Asphalt pavement layer 311 Asphalt mixture 32 Roadbed 33 Road surface 34 Semi-flexible pavement 341 Open-graded asphalt mixture 342 Cement Milk C Cover material V Electric Vehicle

Claims

1. A power supply device that provides non-contact power to a power receiving device installed on a mobile body is embedded in the travel path, and the embedded power supply device structure is as follows: The power supply device comprises a power supply coil and a coil case that houses the power supply coil. The coil case is embedded in the pavement of the road, which is constructed by hardening an asphalt mixture, and its surface is formed to be rough using an intermediate material. The aforementioned intermediate member is During the construction of the aforementioned pavement, the material is made of a material with low thermal conductivity or high heat capacity that can block or delay the conduction of heat from the asphalt mixture before hardening between it and the coil case. An embedded structure for a power supply device, characterized in that it is a member capable of forming a rough surface on the surface of the coil case by being attached to the coil case via a fixing means.

2. A power supply device that provides non-contact power to a power receiving device installed on a moving body, is embedded in the travel path, and the power supply device is embedded in the travel path, The power supply device comprises a power supply coil and a coil case that houses the power supply coil. The coil case is embedded in the pavement of the road, which is constructed by hardening an asphalt mixture, and its surface is formed to be rough using an intermediate material. The aforementioned intermediate member is a three-dimensional mesh-like structure, which is the embedded structure for a power supply device.

3. A power supply device that provides non-contact power to a power receiving device installed on a moving body, is embedded in the travel path, and the power supply device is embedded in the travel path, The power supply device comprises a power supply coil and a coil case that houses the power supply coil. The coil case is embedded in the pavement of the road, which is constructed by hardening an asphalt mixture, and its surface is formed to be rough using an intermediate material. The aforementioned intermediate member is characterized by being a plurality of wooden pieces, and is a buried structure for a power supply device.

4. In the buried structure of a power supply device according to any one of claims 1 to 3, An embedded structure for a power supply device, characterized in that the aforementioned pavement is a semi-flexible pavement.

5. In the buried structure of the power supply device according to claim 4, A buried structure for a power supply device, characterized in that the aforementioned travel path is a road.

6. A method for burying a power supply device to construct a buried structure for a power supply device according to any one of claims 1 to 3, A method for burying a power supply device, characterized by pouring the asphalt mixture and burying the coil case in the asphalt mixture.

7. A method for burying a power supply device according to claim 6, A method for burying a power supply device, characterized by impregnating the asphalt mixture in which the coil case is buried with cement milk.

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