Buried structure and method for power supply device

Abstract

To bury a power supply device for contactlessly supplying power to a power reception device provided on a movable body moving on a driving lane in the vicinity of a road surface while suppressing temporal change of power transmission efficiency.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 coil case equipped with a slip preventive member on an outer peripheral surface thereof and a power supply coil stored in the coil case. The driving lane has a semiflexible pavement body that is formed of cured open-graded asphalt mixture having a concave part on a top surface and cement milk permeating the open-graded asphalt. The coil case is stored in the concave part.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a power supply device embedding structure and a power supply device embedding method for embedding a power supply device in a travel path, the power supply device contactlessly feeding power to a power receiving device provided on a mobile object that moves on the travel path. [Background technology]

[0002] BACKGROUND ART Research and development has been underway on wireless power transmission, which transmits power in a non-contact manner by utilizing a magnetic field resonance phenomenon that occurs between a power supply device and a power receiving device.

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

[0004] This technology is being used in a variety of fields, and is particularly expected to be used in in-motion power transfer systems that supply power to moving vehicles. In an in-motion power transfer system, a power transfer coil provided in a power transfer device and a resonant capacitor connected in series with the power transfer coil are installed on the road side, while a power receiving device equipped with a power receiving coil is installed on the vehicle side. This aims to supply power to a moving vehicle continuously or intermittently in a non-contact manner. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2010-233442 Summary of the Invention [Problem to be solved by the invention]

[0006] As described above, if wireless power supply is possible by burying a power supply device on the roadside, it will be possible to address the issues 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. In this case, considering power transmission efficiency, it is preferable to bury the power supply device in a shallow area near the road surface.

[0007] However, it is known that the area near the road surface can become warped or rutted over a long period of time. This phenomenon is particularly pronounced in areas where vehicles are stationary, such as bus stops, taxi pools, and intersections, where potential installation locations for power supply devices are currently being considered. When ruts form, the distance between the road surface and vehicles changes compared to immediately after the power supply device is installed, which could result in a decrease in the efficiency of power transmission from the road surface over time.

[0008] The present invention has been made in consideration of such problems, and its main objective is to bury a power supply device near the road surface that supplies power contactlessly to a power receiving device provided on a mobile object moving on a roadway while suppressing changes over time in power transmission efficiency. [Means for solving the problem]

[0009] In order to achieve this object, the buried structure for a power supply device of the present invention is a buried structure for a power supply device that is buried in a running path and that supplies power contactlessly to a power receiving device provided on a moving body that moves on the running path, and is characterized in that the power supply device comprises a coil case with a stopper on the outer peripheral surface and a power supply coil housed in the coil case, and the running path comprises a semi-flexible pavement made of an open-graded asphalt mixture that has been hardened with a recess on its upper surface and cement milk that has been permeated into the open-graded asphalt, and the coil case is housed in the recess.

[0010] The buried structure of the power supply device of the present invention is characterized in that a coating layer is laminated on the upper surface of the coil case, and the coating layer is continuous with the upper surface of the open-graded asphalt mixture, forming the road surface of the running path.

[0011] The buried structure of the power supply device of the present invention is characterized in that the coating layer is the cement milk.

[0012] The buried structure of the power supply device of the present invention is characterized in that the covering layer is made of cold-setting asphalt material and the cement milk filled into the gaps in the cold-setting asphalt.

[0013] The buried structure for a power supply device of the present invention is characterized in that the covering layer is made of resin mortar, or in that the covering layer is made of fiber-reinforced cement mortar.

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

[0015] The method for burying a power supply device of the present invention is a method for burying a power supply device for constructing an embedded structure for the power supply device of the present invention, and is characterized in that an open-graded asphalt mixture is poured and a recess is formed on the upper surface thereof, the coil case is then placed in the recess, and the cement milk is allowed to penetrate the open-graded asphalt mixture.

[0016] According to the power supply device burying structure and power supply device burying method of the present invention, a coil case containing a power supply coil is embedded in a recess in the upper surface of the hardened open-graded asphalt mixture. This allows the coil case containing the power supply coil to be embedded near the road surface of a semi-flexible pavement that is resistant to rutting, without coming into contact with the open-graded asphalt mixture that exceeds 200°C before hardening, thereby suppressing changes in power transmission efficiency over time.

[0017] Therefore, by installing a buried power supply device structure using semi-flexible pavement in areas where vehicles are stationary, such as bus stops, taxi pools, and near intersections, where rutting is likely to occur with ordinary asphalt pavement, it is possible to operate an in-motion power supply system stably over the long term.

[0018] Furthermore, the cement milk also fills the gaps between the shear stoppers installed on the coil case and the open-graded asphalt mixture, enhancing the fixation between the coil case and the semi-flexible pavement. Therefore, even if vertical loads from moving objects are repeatedly transmitted to the coil case, rattles do not occur, and the coil case and semi-flexible pavement can be stably integrated over the long term.

[0019] Furthermore, providing a coating layer stiffens the top surface of the coil case, which allows the thickness of the top surface of the coil case to be reduced and the power supply coil to be positioned closer to the road surface, contributing to improved power transmission efficiency. [Effects of the Invention]

[0020] According to the present invention, the power supply device of an in-motion power supply system that supplies power continuously or intermittently to a moving vehicle can be buried near the road surface of semi-flexible pavement that is resistant to rutting, making it possible to suppress changes in power transmission efficiency over time. [Brief explanation of the drawings]

[0021] [Figure 1] 1 is a diagram showing an outline of a traveling power supply system according to an embodiment of the present invention; [Figure 2] 1 is a diagram illustrating an overview of a power supply device according to an embodiment of the present invention. [Figure 3] 1A and 1B are diagrams showing a structure and method for embedding a power supply device according to an embodiment of the present invention (first embodiment); [Figure 4] 5A and 5B are diagrams showing a structure and method for embedding a power supply device according to an embodiment of the present invention (second embodiment); [Figure 5]10A and 10B are diagrams showing a structure and a method for embedding a power supply device according to an embodiment of the present invention (third embodiment); DETAILED DESCRIPTION OF THE INVENTION

[0022] The present invention relates to an embedding structure for embedding a power supply device constituting an in-motion power supply system in a roadway, and the mobile object that moves using the in-motion power supply system is not limited in any way as long as it is an electric vehicle that runs by driving a motor with electricity.

[0023] Furthermore, the roadway on which the power supply device is buried can be any roadway that has a structure that allows the installation of semi-flexible pavement, such as a public road, a highway, or a roadway in a parking lot or factory site.

[0024] In this embodiment, the case where the travel path is a road and semi-flexible pavement is provided on the surface and base layers of the road is taken as an example, and the embedding structure and embedding method of the power supply device will be described in detail with reference to Figures 1 to 5. Before describing the embedding structure of the power supply device, the in-motion power supply system will first be described.

[0025] <<<<<In-motion power supply system 100>>>> As shown in FIG. 1(a), the in-motion power supply system 100 includes a power supply device 10 embedded in a semi-flexible pavement 31 of a road 30, and a power receiving device 20 mounted on an electric vehicle V.

[0026] The power feeding device 10 includes a power feeding coil 11 housed in a coil case 13 and a power supply device 12 connected to the power feeding coil 11. The power supply device 12 generates high-frequency power. The generated high-frequency power is output to the power feeding coil 11. On the other hand, the power receiving device 20 includes 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 electric vehicle V side to form a series resonant circuit.

[0027] As a result, the power receiving coil 21 and the power supply coil 11 are magnetically coupled by magnetic field resonance, and high-frequency power is transmitted from the power supply device 10 to the power receiving coil 21. The transmitted high-frequency power is supplied to the load 22 of the electric vehicle V. In this way, the in-motion power supply system 100 can wirelessly supply power from the power supply device 10 embedded in the semi-flexible pavement 31 to the power receiving device 20 mounted on the electric vehicle V.

[0028] <<Buried power supply device structure>> In the in-motion 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 FIG. 2(a) and is embedded in a semi-flexible pavement 31 that constitutes the base and surface layers of a road 30.

[0029] The coil case 13 is made of an impact-resistant material (for example, polycarbonate, polypropylene, or hard rubber). The entire case, including the outlet portion for the wire that forms the power supply coil 11, is provided with a structure that enhances waterproofing. Furthermore, as shown in FIGS. 2(a) and 2(b), the coil case 13 is provided with a plurality of anti-slip members 14 on its side circumferential surface and bottom surface.

[0030] The anti-slip member 14 is provided to enhance adhesion with the semi-flexible pavement 31 described below, and any member may be used as long as it can ensure a degree of fixation with the cement milk 312 used in the semi-flexible pavement 31, as shown in Figure 1(b). Examples include stud dowels, headed studs, and perforated steel plates, which are used to enhance adhesion between concrete and steel materials.

[0031] Considering power transmission efficiency, the coil case 13 having the above configuration is preferably buried near the road surface 33. For this reason, for example, as shown in Fig. 1(a), the coil case 13 is manufactured to have a robust structure, and is buried in the semi-flexible pavement 31 so that its upper surface is covered with a cover material C or the like to make it continuous with the road surface 33. Alternatively, as shown in Fig. 1(b), a covering layer S is provided on the upper surface of the coil case 13, and the coil case is buried in the semi-flexible pavement 31 so that this covering layer S is aligned with the road surface 33.

[0032] The semi-flexible pavement 31 has excellent resistance to plastic deformation and can suppress the occurrence of rutting. Therefore, as shown in Figures 1(a) and 1(b), when the coil case 13 is embedded in the semi-flexible pavement 31, it is possible to suppress the change over time in the distance L between the electric vehicle V and the coil case 13 embedded in the semi-flexible pavement 31.

[0033] In other words, it is possible to avoid large changes in the distance L between the power receiving coil 21 mounted on the electric vehicle V and the power supply coil 11 housed in the coil case 13, and to maintain stable power transmission efficiency over the long term. Therefore, by providing an embedded structure for power supply device 10 using semi-flexible pavement 31 in areas where vehicles are stationary, such as near bus stops, taxi pools, and intersections, where rutting is likely to occur on ordinary asphalt pavement, it is possible to operate an in-motion power supply system stably over the long term.

[0034] As shown in FIG. 1(b), the semi-flexible pavement 31 is a pavement in which cement milk 312 is infiltrated into the voids in an open-graded asphalt mixture 311. The construction process involves pouring an open-graded asphalt mixture at temperatures exceeding 200°C onto the roadbed 32. Therefore, if the construction of the semi-flexible pavement 31 and the embedding of the coil case 13 constituting the power supply device 10 into the semi-flexible pavement 31 are carried out simultaneously, the coil case 13 will be exposed to a high-temperature environment exceeding 200°C, which could damage the power supply coil 11 housed in the coil case 13.

[0035] Therefore, in this embodiment, the coil case 13 is embedded in the semi-flexible pavement 31 by the method shown in the first to third embodiments, without being exposed to a high temperature environment exceeding 200°C.

[0036] First Embodiment In the first embodiment, as shown in Figure 1(a), the coil case 13 is buried in a semi-flexible pavement 31 so that the top surface thereof is covered with a cover material C or the like and is continuous with the road surface 33.

[0037] First, as shown in Figure 3(a), an open-graded asphalt mixture 311 is poured onto the roadbed 32, and an installation space P for storing the coil case 13 is formed on the upper surface thereof. For example, the installation space P is prepared by placing a formwork of the same shape as the installation space P in advance, a process known as box punching, and then the high-temperature open-graded asphalt mixture 311 is poured.

[0038] Next, when the open-graded asphalt mixture 311 has hardened and its temperature has dropped, the coil case 13 is placed in the installation space P, as shown in Figure 3(b). A gap is then created between the anti-slip member 14 of the coil case 13 and the open-graded asphalt mixture 311.

[0039] Therefore, as shown in Figure 3(c), cement milk 312 is allowed to penetrate into the voids in the open-graded asphalt mixture 311, and the cement milk 312 is filled into the gap between the shear stopper 14 and the open-graded asphalt mixture 311. After this, the upper surface of the coil case 13 is appropriately covered with a cover material C made of an elastic material such as rubber. As a result, a semi-flexible pavement 31 is constructed on the roadbed 32, and an embedded structure for the power supply device 10 is formed.

[0040] According to the above procedure, the coil case 13 is placed when the temperature of the open-graded asphalt mixture 311 has dropped and hardened, so the coil case 13 does not need to be heat-resistant, and the power supply coil 11 housed in the coil case 13 is not exposed to high temperatures.

[0041] Furthermore, the cement milk 312 is filled not only into the voids in the open-graded asphalt mixture 311 but also between the shear stoppers 14 provided on the coil case 13, thereby increasing the degree of fixation between the coil case 13 and the semi-flexible pavement 31. Therefore, even if vertical loads from an electric vehicle V or the like are repeatedly transmitted to the coil case 13, rattles do not occur, and the coil case 13 and the semi-flexible pavement 31 can be stably integrated over the long term.

[0042] Second Embodiment In the second embodiment, as shown in Figure 1(b), a coating layer S is provided on the upper surface of the coil case 13, and the coil case 13 is embedded in the semi-flexible pavement 31 so that this coating layer S is aligned with the road surface 33.

[0043] First, as shown in Figure 4(a), an open-graded asphalt mixture 311 is poured onto the roadbed 32, and an installation space P is formed on the top surface of the mixture, deep enough to accommodate the coil case 13 laminated with the covering layer S. As in the first embodiment, a formwork of the same shape as the installation space P is placed in advance, a process known as box punching, and the hot open-graded asphalt mixture 311 is poured into the installation space P. Note that after the open-graded asphalt mixture 311 has hardened, a recess may be formed by cutting, and this may be used as the installation space P.

[0044] Next, when the open-graded asphalt mixture 311 has hardened and its temperature has dropped, the coil case 13 is placed in the installation space P, as shown in Figure 4(b). This creates a gap between the anti-slip member 14 of the coil case 13 and the open-graded asphalt mixture 311, and also creates a space above the coil case 13.

[0045] As shown in Fig. 4(c), cold setting asphalt mixture 313 is poured with open grading into the gaps around these shear stoppers 14 and into the space above the coil case 13. After this, cement milk 312 is allowed to penetrate into the gaps in the cold setting asphalt mixture 313 and the gaps in the open-graded asphalt mixture 311, as shown in Fig. 4(d).

[0046] As a result, a semi-flexible pavement 31 is constructed on the roadbed 32, and a buried structure for the power supply device 10 is formed on the upper surface of the coil case 13, with a covering layer S made of a pavement made by infiltrating cement milk 312 into a room temperature hardening asphalt mixture 313 being laminated thereon.

[0047] According to the above procedure, as in the first embodiment, it is possible to embed the power supply device 10 in the semi-flexible pavement 31 without placing the power supply coil 11 housed in the coil case 13 in a high-temperature environment. In addition, the top surface of the coil case 13 is reinforced by the coating layer S. Therefore, as shown in FIG. 4(d), the thickness of the top side of the coil case 13 can be reduced to bring the power supply coil 11 closer to the road surface 33, which can also contribute to improving power transmission efficiency.

[0048] The covering layer S laminated on the top surface of the coil case 13 may be made of any material that is compatible with the semi-flexible pavement 31 and can stiffen the coil case 13.

[0049] <<Third Embodiment>> In the third embodiment, an embedded structure of the power supply device 10 is exemplified, in which the covering layer S is made of cement milk 312 and resin mortar 314 that form the semi-flexible pavement 31.

[0050] The construction procedure is the same as that of the second embodiment. First, as shown in Figure 5(a), an open-graded asphalt mixture 311 is poured onto the roadbed 32, and an installation space P is formed on top of it, deep enough to accommodate the coil case 13 laminated with the covering layer S. Next, when the open-graded asphalt mixture 311 has hardened and its temperature has dropped, the coil case 13 is placed in the installation space P, as shown in Figure 5(b).

[0051] <When using Cement Milk 312 for the coating layer S> Thereafter, when forming the coating layer S with cement milk 312, as shown in Fig. 5(c), the cement milk 312 is allowed to penetrate into the voids in the open-graded asphalt mixture 311. Furthermore, the cement milk 312 is filled into the gaps between the anti-slip members 14 of the coil case 13 and the open-graded asphalt mixture 311, and into the space above the coil case 13.

[0052] As a result, the semi-flexible pavement 31 is constructed on the roadbed 32, and a covering layer S made of cement milk 312 is laminated on the upper surface of the coil case 13, thereby forming an embedded structure for the power supply device 10.

[0053] <When Resin Mortar 314 is used for the coating layer S> On the other hand, when forming the covering layer S with resin mortar 314, as shown in Figure 5(b), after storing the coil case 13 in the installation space P, first, cement milk 312 is allowed to penetrate into the voids in the open-graded asphalt mixture 311 to construct the semi-flexible pavement 31. After this, resin mortar 314 is filled into the gaps between the shear stopper members 14 of the coil case 13 and the open-graded asphalt mixture 311, and into the space above the coil case 13.

[0054] It is also possible to use fiber-reinforced cement mortar or an inexpensive cement-based material instead of the resin mortar 314. The resin mortar 314 is known to have impact resistance and abrasion resistance, and the fiber-reinforced cement mortar is known to be a material with excellent toughness. By using these materials, the covering layer S can be made thinner to protect the coil case 13. For example, it is also possible to use both resin mortar 314 up to the surface of the coil case 13 and fiber-reinforced cement mortar above that, or both.

[0055] The embedding structure of the power supply device and the embedding method of the power supply device of the present invention are not limited to the above-described embodiments, and it goes without saying that various modifications are possible within the scope of the present invention.

[0056] For example, the coil case 13 may house not only the power supply coil 11 but also the equipment necessary for the power supply device 10. Furthermore, the coil case 13 may house the equipment necessary for the power supply device 10 alone.

[0057] Furthermore, there are no limitations on the mix ratio of aggregate and asphalt binder, or the void ratio, of the open-graded asphalt mixture 311 that makes up the semi-flexible pavement 31. Furthermore, the open-graded asphalt mixture 311 may be poured in multiple layers, or in one layer.

[0058] Furthermore, any type of cement milk 312 can be used as long as it is a material that can be used in the semi-flexible pavement 31. Therefore, if cement milk 312 whose main ingredient is low-carbon cement that can significantly reduce CO2 emissions is used, it becomes possible to make the buried structure of the power supply device 10 using the semi-flexible pavement 31 an environmentally friendly structure.

[0059] In addition, in this embodiment, a full permeation type in which the cement milk 312 permeates the entire semi-flexible pavement 31 has been exemplified, but this is not limiting. If the coil case 13 and the semi-flexible pavement 31 can be integrated, a semi-permeation type in which the cement milk 312 permeates only the upper half may be adopted.

[0060] Furthermore, although the present embodiment uses the "magnetic coupling method" as an example for the power supply coil 11 constituting the in-motion power supply system 100, it is also possible to adopt the "electrolytic coupling method." [Explanation of symbols]

[0061] 100 In-motion power supply system 10 Power supply device 11 Power supply coil 12 Power supply 13 Coil case 14 Shear stopper 20 Power receiving device 21 Receiving coil 22 Load 30 road 31 Semi-flexible pavement 311 Open-graded asphalt mixture 312 Cement Milk 313 Cold-setting asphalt mixture 314 Resin mortar 32 Roadbed 33 Road surface P Installation space (recess) C Cover material H Installation space S coating layer

Claims

1. A buried structure for a power supply device in which a power supply device that supplies power in a non-contact manner to a power receiving device provided on a moving body that moves on a traveling path is buried in the traveling path, the power supply device includes a coil case having a stopper member on an outer circumferential surface; a power supply coil housed in the coil case, The roadway is provided with a semi-flexible pavement body made of an open-graded asphalt mixture that has been hardened with a recess on the upper surface and cement milk that has been permeated into the open-graded asphalt, The buried structure of the power supply device, wherein the coil case is housed in the recess.

2. The buried structure for a power supply device according to claim 1, a coating layer is laminated on the upper surface of the coil case; The covering layer is continuous with the upper surface of the open-graded asphalt mixture and forms the road surface of the travel path.

3. The buried structure for a power supply device according to claim 2, The buried structure for a power supply device, wherein the covering layer is the cement milk.

4. The buried structure for a power supply device according to claim 2, 1. A buried structure for a power supply device, wherein the covering layer is made of cold-setting asphalt material and the cement milk filled into the gaps in the cold-setting asphalt.

5. The buried structure for a power supply device according to claim 2, The buried structure for a power supply device, wherein the covering layer is made of resin mortar.

6. The buried structure for a power supply device according to claim 2, The buried structure for a power supply device, wherein the covering layer is made of fiber-reinforced cement mortar.

7. The buried structure for a power supply device according to any one of claims 1 to 6, The buried structure for a power supply device, wherein the running path is a road.

8. A method for burying a power supply device for constructing the buried structure of the power supply device according to any one of claims 1 to 6, comprising: After pouring the open-graded asphalt mixture and creating a recess on its top surface, A method for burying a power supply device, characterized in that the coil case is stored in the recess and the cement milk is allowed to penetrate into the open-graded asphalt mixture.

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