Buried structure of power supply equipment

Abstract

The objective is to create a semi-flexible pavement structure suitable for burying a power supply device that provides non-contact power to a power receiving device installed on a moving body, while maintaining resistance to plastic deformation. [Solution] A buried structure for a power supply device that non-contactually supplies power to a power receiving device provided on a moving body, the power supply device comprising a power supply coil and a coil case housing the power supply coil, the road being made of a semi-flexible pavement body in which a cement-based solidification liquid is impregnated into an open-graded asphalt mixture layer, the cement-based solidification liquid impregnated into the lower layer contains a high thermal conductivity material having higher thermal conductivity than the cement-based solidification liquid, and the coil case is in contact with the lower layer of the semi-flexible pavement body.

Description

Technical Field

[0001] The present invention relates to a buried structure of a power supply device for non-contact power supply to a power receiving device provided on a moving body in a semi-flexible pavement.

Background Art

[0002] Conventionally, research and development of a wireless power transmission system that performs non-contact power transmission by utilizing a magnetic field resonance phenomenon (magnetic field resonance phenomenon) occurring between a power supply device and a power receiving device has been promoted. Such technology is utilized in various fields, and in particular, it is expected to be used for in-motion power supply that supplies power to a vehicle while it is running.

[0003] For example, Patent Document 1 discloses an in-wheel motor system that controls an in-wheel motor in which a drive source is arranged inside a wheel of an electric vehicle or the like, which is an example of in-motion power supply. The in-wheel motor supplies power from the vehicle body side to the wheel side. In addition to this, Patent Document 1 discloses a configuration that enables power supply from the road surface to the wheel side.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] As disclosed in Patent Document 1, if a power supply device is buried in a road surface to enable wireless power supply, it becomes possible to address problems of electric vehicles such as short cruising time and long charging time. Therefore, it is possible to promote the use of electric vehicles and contribute to reducing carbon dioxide emissions due to transportation. Considering power transmission efficiency, such a power supply device is preferably buried at a shallow depth near the road surface, that is, in the pavement.

[0006] However, it is known that pavement can sag and develop rutting over long periods of use. When rutting occurs, the distance between the road surface and the vehicle changes compared to immediately after the power supply equipment was installed, which may cause the power transmission efficiency from the road surface to decrease over time. For this reason, the application of a semi-flexible pavement, which has excellent resistance to plastic deformation and can suppress the occurrence of rutting, is desired for pavement in which power supply equipment is installed.

[0007] However, semi-flexible pavement does not have the ability to absorb and dissipate heat if the power supply equipment generates heat during use and heat accumulates inside the equipment, which may cause malfunctions in the power supply equipment.

[0008] The present invention has been made in view of the above problems, and its main objective is to provide a semi-flexible pavement body with a structure suitable for burying a power supply device that supplies power to a power receiving device installed on a moving body in a non-contact manner, while maintaining resistance to plastic deformation. [Means for solving the problem]

[0009] To achieve this objective, the present invention provides an embedded structure for a power supply device, which is embedded in a travel path and provides a power supply device that supplies power to a power receiving device provided on a mobile body in a non-contact manner, wherein the power supply device comprises a power supply coil and a coil case housing the power supply coil, and the travel path comprises a semi-flexible pavement body in which a cement-based solidification liquid is impregnated into an open-graded asphalt mixture layer, the cement-based solidification liquid impregnated into the lower part of the semi-flexible pavement body contains a high thermal conductivity material having higher thermal conductivity than the cement-based solidification liquid, and the coil case is embedded in contact with the lower part of the semi-flexible pavement body.

[0010] The buried structure of the power supply device of the present invention is characterized in that the cement-based solidification liquid that permeates the upper layer of the semi-flexible pavement contains a solar reflective material.

[0011] The buried structure of the power supply device of the present invention is characterized in that the high thermal conductivity material contains silicon waste material. Furthermore, the cement-based solidification liquid is characterized in that it contains concrete waste material.

[0012] The buried structure of the power supply device of the present invention is characterized in that the aforementioned travel path is a road.

[0013] Because the semi-flexible pavement of the present invention is permeated with a cement-based solidification liquid containing a highly thermally conductive material, it can diffuse the heat conducted from the road surface, whose surface temperature has risen due to solar radiation, into the roadbed, thereby lowering the temperature inside the semi-flexible pavement.

[0014] Furthermore, the semi-flexible pavement is constructed by impregnating at least the upper layer with a cement-based solidification liquid containing a solar-reflective material. This reduces the rise in surface temperature due to solar radiation due to increased surface reflectivity, thereby lowering the internal temperature of the entire semi-flexible pavement.

[0015] Furthermore, the inclusion of concrete waste maintains or improves the plastic deformation resistance of the semi-flexible pavement. Therefore, even when vertical loads such as those from moving bodies are repeatedly transmitted, deflection and rutting can be suppressed in the same way as with conventional semi-flexible pavements.

[0016] On the other hand, by including concrete waste, the amount of fresh cement-based solidifying agent used in the cement-based solidifying liquid can be reduced, thereby reducing the amount of carbon dioxide emitted during the manufacture of the cement-based solidifying agent. In addition, carbon dioxide from the atmosphere can be fixed to the semi-flexible pavement. Furthermore, in the initial stages after the construction of the semi-flexible pavement, the degree of alkalinity of rainwater drainage caused by rainfall can be reduced.

[0017] Furthermore, by using silicon waste materials, such as those used in solar panels, as a high thermal conductivity material, combined with the use of concrete waste, it becomes possible to create environmentally friendly pavement.

[0018] According to the embedding structure of the power supply device of the present invention, a coil case for housing a power supply coil is embedded in the above-mentioned semi-flexible pavement. Thus, if the coil case is arranged to contact the lower layer portion of the semi-flexible pavement containing a high thermal conductivity material, when the power supply coil generates heat and heat accumulates in the coil case, the heat of the coil case can be diffused into the semi-flexible pavement. Thereby, it becomes possible to quickly reduce the temperature inside the coil case and protect the power supply coil that is vulnerable to high temperatures.

[0019] In addition, since the semi-flexible pavement contains a solar radiation reflective material in its upper layer portion, when the road surface receives solar radiation, the rise in the internal temperature of the semi-flexible pavement is suppressed, and it becomes possible to protect the power supply coil housed in the coil case without exposing it to a high-temperature environment.

[0020] In addition, since the semi-flexible pavement contains waste concrete, the generation of rutting can be avoided by maintaining the plastic deformation resistance, and there is no large change over time in the distance between the moving body traveling on the road surface and the road surface. Therefore, the embedding structure of the power supply device can stably maintain the power transmission efficiency over a long period.

Effect of the Invention

[0021] According to the present invention, since the lower layer portion of the semi-flexible pavement contains a high thermal conductivity material, when a power supply device that supplies power non-contact to a power receiving device provided on a moving body generates heat and heat accumulates in the device, this heat can be absorbed and diffused into the semi-flexible pavement, and it becomes possible to make the semi-flexible pavement have a structure suitable for embedding the power supply device.

Brief Description of the Drawings

[0022] [Figure 1] It is a diagram showing a semi-flexible pavement provided on a road surface in an embodiment of the present invention. [Figure 2] It is a diagram showing an outline of a power supply system during traveling in an embodiment of the present invention. [Figure 3] It is a diagram showing another example of the embedding structure of the power supply device in an embodiment of the present invention.

Embodiment for Carrying out the Invention

[0023] The present invention can be adopted for any traveling road where a semi-flexible pavement can be provided, such as roads provided on general roads, highways, parking lots, factory sites, etc.

[0024] In addition, the power supply device embedded in the semi-flexible pavement may be any as long as it constitutes a power supply system during travel that continuously or intermittently supplies power to a moving body during travel. Furthermore, the moving body that moves using the power supply system during travel is not limited in any way as long as it is an electric vehicle that drives a motor by power to travel.

[0025] In the present embodiment, a case where the traveling road for embedding the power supply device is a road provided with a semi-flexible pavement is taken as an example, and the details of the semi-flexible pavement and the embedding structure of the power supply device will be described with reference to FIGS. 1 to 3.

[0026] ≪≪Semi-flexible Pavement≫≫ As shown in FIG. 1, on a road 30, a semi-flexible pavement 31 is constructed on a roadbed 32. The semi-flexible pavement 31 includes a high heat conduction layer 31a provided in the lower layer portion and a solar radiation reflective layer 31b provided in the upper layer portion.

[0027] The high heat conduction layer 31a is constructed by infiltrating cement milk 312 with high heat conduction performance into the voids of the open-graded asphalt mixture layer 311. On the other hand, the solar radiation reflective layer 31b is constructed by infiltrating cement milk 313 with solar radiation reflective performance into the voids of the open-graded asphalt mixture layer 311.

[0028] The open-graded asphalt mixture layer 311 is composed of aggregates (coarse aggregates, fine aggregates, and fillers) and an asphalt binder for both the high heat conduction layer 31a and the solar radiation reflective layer 31b, and their mixing ratios, void ratios, etc. are not limited in any way.

[0029] The cement milk 312, which is given high thermal conductivity, contains a high thermal conductivity material 14 in addition to a cement-based solidifying agent and water. The high thermal conductivity material 14 can be any granular or powder form that has a higher thermal conductivity than the cement milk 312 and does not hinder the fluidity of the cement milk 312. For example, silicon waste obtained from silicon-based panels used in solar power generation can be cited as an example of the high thermal conductivity material 14.

[0030] The cement milk 313, which has been given solar radiation reflecting properties, contains a solar radiation reflecting material 15 and concrete waste material 16 in addition to a cement-based solidifying agent and water. The concrete waste material 16 can be any granular or powder form that does not hinder the fluidity of the cement milk 313. For example, fine waste concrete powder remaining after removing recycled coarse aggregate from concrete can be used.

[0031] Furthermore, the solar reflective material 15 is a material generally used to reduce the surface temperature of asphalt pavement, improve the durability of the pavement, and mitigate or suppress the heat island effect. Any granular or powdery material that does not hinder the fluidity of the cement milk 313 may be used. For example, shell powder such as oyster shells or scallop shells can be cited as an example.

[0032] In the semi-flexible pavement 31 having the above configuration, the cement slurry 313 that has permeated into the solar radiation reflecting layer 31b contains concrete waste material 16, thus reducing the amount of fresh cement-based solidifying agent that needs to be added. This reduces the amount of carbon dioxide emitted during the production of the cement-based solidifying agent. Furthermore, the inclusion of concrete waste material 16 allows for the fixation of atmospheric carbon dioxide in the solar radiation reflecting layer 31b.

[0033] Furthermore, it becomes possible to make the semi-flexible pavement 31 an environmentally friendly structure, such as by reducing the degree of alkalinity of rainwater drainage caused by exposure to rainfall in the initial stages after the construction of the semi-flexible pavement 31.

[0034] Furthermore, because it contains a solar-reflective material 15, the amount of surface temperature rise due to solar radiation can be reduced by increasing the reflectivity of the surface. In addition, the reduction in the amount of surface temperature rise can suppress the temperature rise inside the semi-flexible pavement 31.

[0035] In addition, the high thermal conductivity layer 31a that constitutes the lower layer is permeated with cement grout 312 containing a high thermal conductivity material 14. Therefore, the heat from the solar reflectance layer 31b can be diffused to the roadbed 32, and the internal temperature of the semi-flexible pavement 31 can be reduced.

[0036] Furthermore, there are no restrictions on the thickness of the solar reflectance layer 31b and the high thermal conductivity layer 31a. In addition, the open-graded asphalt mixture layer 311 may use the same material for both the solar reflectance layer 31b and the high thermal conductivity layer 31a, or it may be modified as appropriate by changing the mix or the type of aggregate.

[0037] Furthermore, the construction method for the semi-flexible pavement 31 can follow general construction procedures. Roughly speaking, an open-graded asphalt mixture layer 311 is poured onto the road base 32. It is then spread, compacted, and cured to harden. After this, cement milk 312 and 313 are sequentially permeated into the pavement. At this time, the open-graded asphalt mixture layer 311 may be constructed in multiple layers or in a single layer.

[0038] Reinforcement materials such as reinforcing bars are not required for the semi-flexible pavement 31 described above. Therefore, concrete waste materials 16 as described above, or solar reflective materials 15 such as seashell powder can be added to the cement milk 313 to which solar reflective performance has been added.

[0039] Furthermore, while the semi-flexible pavement 31 has an environmentally friendly structure, its resistance to plastic deformation can be maintained or improved by including concrete waste 16 in the solar reflectance layer 31b. Therefore, this semi-flexible pavement 31 can be used in areas where vehicles congregate, such as bus stops, taxi stands, and intersections, where rutting is likely to occur in conventional asphalt pavements.

[0040] The semi-flexible pavement 31 having the above-described performance is suitable as a pavement in which a power supply device 10 that provides contactless power to a power receiving device 20 installed on an electric vehicle V moving on a road 30 is embedded, as shown in Figure 2(a). The embedded structure of the power supply device 10 using the above-described semi-flexible pavement 31 will be described below. Prior to that, a power supply system 100 that includes a power supply device 10 and a power receiving device 20 will be described.

[0041] <<<<On-Driving Power Supply System 100>>>> As shown in Figures 2(a) and (b), the in-vehicle 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 semi-flexible pavement 31 of the road 30.

[0042] 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.

[0043] 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-movement power supply system 100 can wirelessly supply power from the power supply device 10 embedded in the semi-flexible pavement 31 to the receiving device 20 mounted on the electric vehicle V.

[0044] <<<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(b) and embedded in the semi-flexible pavement 31 that constitutes the road 30.

[0045] The coil case 13 is made of an impact-resistant material (for example, polycarbonate, polypropylene, or hard rubber). Furthermore, the entire structure, including the exit point for the wires forming the power supply coil 11, is designed to enhance waterproofing.

[0046] <<The entire coil case 13 is embedded in the high thermal conductivity layer 31a>> As shown in Figure 2(a), the coil case 13 described above is entirely embedded within the high thermal conductivity layer 31a located below the solar reflectance layer 31b.

[0047] As a result, if the power supply coil 11 generates heat during operation and heat accumulates inside the coil case 13, this heat is conducted from the coil case 13 to the high thermal conductivity layer 31a and then diffused within the high thermal conductivity layer 31a. Therefore, the temperature inside the coil case 13 can be rapidly reduced, protecting the power supply coil 11, which is vulnerable to high temperatures.

[0048] Furthermore, the upper surface of the coil case 13 is covered with a solar reflective layer 31b. As described above, the solar reflective layer 31b reduces the temperature of the road surface 33 by increasing the reflectivity of its surface, and also suppresses high temperatures within the solar reflective layer 31b. Therefore, the heat conducted from the solar reflective layer 31b to the coil case 13 is also reduced compared to general semi-flexible pavement. This prevents the housed power supply coil 11 from being exposed to high-temperature environments on a daily basis.

[0049] Furthermore, vertical loads from electric vehicles V and other vehicles traveling on the road surface 33 are transmitted to the coil case 13 via the solar reflectance layer 31b, whose compressive strength has been increased by the application of concrete waste material 16. Therefore, the impact acting on the power supply coil 11 housed in the coil case 13 due to the vertical load can be reduced. In addition, the upper surface of the coil case 13 is stiffened by the covering layer S. Therefore, the thickness of the upper surface of the coil case 13 can be reduced, bringing the power supply coil 11 closer to the road surface 33, which can contribute to improving power transmission efficiency.

[0050] Furthermore, by embedding the coil case 13 in the semi-flexible pavement 31, which is less prone to rutting on the road surface 33, 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 running on the road surface 33 and the coil case 13, that is, the distance to the power supply coil 11 housed therein. Therefore, the embedded structure of the power supply device 10 can maintain stable power transmission efficiency over a long period of time.

[0051] <The coil case 13 is buried with the road surface 33 exposed.> The depth position of the coil case 13 embedded in the semi-flexible pavement 31 is not limited to within the high thermal conductivity layer 31a. For example, as shown in Figure 3(a), it may be embedded within the solar reflectance layer 31b in a manner that is continuous with the road surface 33, with its upper surface covered by a cover material C made of an elastic material such as rubber.

[0052] In this case, it is preferable to keep at least the lower surface of the coil case 13 in contact with the high thermal conductivity layer 31a. This allows the high thermal conductivity layer 31a to absorb and dissipate the heat when the inside of the coil case 13 becomes a high-temperature environment due to sunlight, or when the power supply coil 11 generates heat and heat accumulates inside the coil case 13, thereby rapidly lowering the temperature inside the coil case 13.

[0053] The above-described buried structure is suitable for roads 30 with low traffic volume, for example, and since vertical loads from electric vehicles V traveling on the road surface 33 are directly transmitted to the coil case 13, it is desirable to make the coil case 13 a robust structure.

[0054] ≪The entire coil case 13 is embedded within the solar reflectance layer 31b≫ On the other hand, on roads with heavy traffic 30, the entire coil case 13 may be embedded in the high thermal conductivity layer 31a as shown in Figure 2(a), or embedded in the solar reflectance layer 31b as shown in Figure 3(b). In this case as well, it is preferable to keep at least the lower surface of the coil case 13 in contact with the high thermal conductivity layer 31a.

[0055] Thus, when burying the entire coil case 13, the burying depth of the coil case 13 should be appropriately set so as to have minimal impact on the power transmission efficiency of the power supply coil 11.

[0056] As described above, the semi-flexible pavement 31, which has a solar reflecting layer 31b and a high thermal conductivity layer 31a, is suitable for installation in areas where vehicles are congested and for burying power supply equipment 10 that is vulnerable to vibration and heat.

[0057] The buried structure for a power supply device and the method for burying 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.

[0058] For example, in this embodiment, a configuration in which the coil case 13 is embedded in either the high thermal conductivity layer 31a or the solar reflectance layer 31b is illustrated, but the invention is not limited to this, and a configuration in which it is embedded at the boundary between the two is also possible.

[0059] Furthermore, although the example given illustrates a case where the semi-flexible pavement 31 has a two-layer structure consisting of a high thermal conductivity layer 31a and a solar reflectance layer 31b, the solar reflectance layer 31b may be omitted, for example. In this case, the upper layer may be constructed as a pavement layer in which a surface treatment material that increases solar reflectance is applied to a conventional semi-flexible pavement.

[0060] Furthermore, in this embodiment, concrete waste 16 was added to the cement grout 313 impregnated into the solar reflectance layer 31b. However, the concrete waste 16 may also be added to the cement grout 312 impregnated into the high thermal conductivity layer 31a. In addition, low-carbon cement may be used in the cement-based solidification material containing both cement grouts 312 and 313. Doing so can further contribute to reducing carbon dioxide emissions.

[0061] In addition, the coil case 13 constituting the power supply device 10 may have other configurations. For example, a shear-preventing member capable of increasing adhesion with cement grout 312 and 313 may be provided on its outer surface. This makes it possible to stably embed the coil case 13 near the road surface 33 of the semi-flexible pavement 31 without rattling, even when vertical loads such as those from electric vehicles V are repeatedly transmitted to the coil case 13.

[0062] Furthermore, any shear-preventing member can be used as long as it can ensure a degree of fixation between the cement grout 312 and 313. For example, examples include protrusions such as stud dowels or studs with heads, or perforated steel plates, which are used to improve the adhesion between concrete and steel.

[0063] Furthermore, the coil case 13 may house not only the power supply coil 11 but also the equipment necessary for the power supply device 10. Moreover, it may house other equipment used in the power supply equipment separately.

[0064] 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". [Explanation of symbols]

[0065] 100 In-Driving Power Supply System 10 Power supply device 11 Power supply coil 12 Power supply 13 Coil Cases 14. High thermal conductivity materials 15 Solar-reflective materials 16 Concrete waste 20 Power receiving equipment 21 Power receiving coil 22 load 30 road 31 Semi-flexible pavement 31a High thermal conductivity layer (lower part) 31b Solar reflecting layer (upper part) 311 Open-graded asphalt mixture layer 312 Cement Milk (with high thermal conductivity) 313 Cement Milk (with solar radiation reflectance properties) 32 Roadbed 33 Road surface 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 aforementioned roadway comprises a semi-flexible pavement formed by impregnating an open-graded asphalt mixture layer with a cement-based solidification liquid, and the cement-based solidification liquid impregnated into the lower portion of the semi-flexible pavement contains a high thermal conductivity material having a higher thermal conductivity than the cement-based solidification liquid. An embedded structure for a power supply device, characterized in that the coil case is embedded in contact with the lower layer of the semi-flexible pavement.

2. The buried structure for a power supply device according to claim 1, A buried power supply device structure characterized in that the cement-based solidification liquid impregnated into the upper layer of the semi-flexible pavement contains a solar radiation reflecting material.

3. A buried structure for a power supply device according to claim 1 or 2, A buried structure for a power supply device, characterized in that the aforementioned high thermal conductivity material contains silicon waste material.

4. A buried structure for a power supply device according to claim 1 or 2, A power supply device characterized in that the cement-based solidification liquid contains concrete waste material. Its buried structure.

5. The buried structure for a power supply device according to claim 1, A buried structure for a power supply device, characterized in that the aforementioned travel path is a road.

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