Non-contact power supply system and sheet member

Abstract

To provide a non-contact power supply system and a sheet member, capable of suppressing variation in inductance on the side of a power transmission device to stably supply power.SOLUTION: A non-contact power supply system comprises: a power transmission device 10 that is arranged along a movement path of a mobile and supplies high-frequency power to a power reception device 20 in a non-contact manner using magnetic coupling; and a sheet member 30 that is attachable to an opposite surface, which is a surface facing the power transmission device, of the mobile. The sheet member includes a first member 31 formed using soft magnetic material and a second member 32 formed using non-magnetic material that are arranged parallelly in a row along at least one direction of a movement direction of the mobile and a direction orthogonal to the movement direction of the mobile.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] An embodiment of the present invention relates to a contactless power supply system and a sheet member. [Background technology]

[0002] In recent years, attention has been focused on contactless power transfer devices that transmit power to electronic devices, electric mobility, and the like without using cables. Specifically, for example, a power receiving coil mounted on an automated guided vehicle traveling along a route in a factory is charged contactlessly using a power transmitting coil installed on the route of the automated guided vehicle. Furthermore, Patent Document 1 describes a technology in which a magnetic body is provided around a power receiving coil in order to suppress a decrease in the power receiving efficiency of the power receiving coil. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-033524 Summary of the Invention [Problem to be solved by the invention]

[0004] However, when transmitting and receiving power contactlessly using magnetic coupling due to magnetic field resonance in a high frequency band such as the HF band, if a magnetic body is provided in the power receiving device, the magnetic body may increase the inductance on the power transmitting side, which may cause problems such as increased loss due to a change in the resonance frequency, making it difficult to transmit and receive power stably.

[0005] Therefore, an embodiment of the present invention provides a contactless power supply system and a sheet member that can suppress fluctuations in inductance on the power transmission device side and supply power stably. [Means for solving the problem]

[0006] The contactless power supply system of the embodiment includes a power transmission device that is arranged along the movement path of a moving body and supplies high-frequency power to a power receiving device contactlessly using magnetic coupling, and a sheet member that can be attached to an opposing surface of the moving body that faces the power transmission device, and the sheet member has a first member made of a soft magnetic material and a second member made of a non-magnetic material that are arranged in a row along at least one of the movement direction of the moving body and a direction perpendicular to the movement direction of the moving body.

[0007] The sheet member of the embodiment is a sheet member applied to a contactless power supply system including a power transmission device arranged along the movement path of a moving body, and the sheet member is provided on an opposing surface of the moving body that faces the power transmission device, and a first member formed of a soft magnetic material and a second member formed of a non-magnetic material are formed in a row along at least one direction of the movement direction of the moving body and a direction perpendicular to the movement direction of the moving body. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a diagram illustrating an example of a configuration of a contactless power supply system according to a first embodiment. [Figure 2] 1A is a diagram illustrating an example of a configuration of a power transmitting device and a power receiving device in a contactless power supply system according to a first embodiment; FIG. 1B is a cross-sectional view illustrating an example of a state in which a power receiving coil is installed on a sheet member; [Figure 3] FIG. 10 is a plan view showing an example of a state in which a power receiving coil is installed on a sheet member in a contactless power supply system according to a second embodiment. [Figure 4] FIG. 10 is a diagram illustrating an example of the configuration of a power transmitting device and a power receiving device in a contactless power supply system according to a third embodiment. [Figure 5] FIG. 10 is a diagram schematically illustrating another example of the configuration of the sheet member in the contactless power supply system according to the third embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, several embodiments will be described with reference to the drawings. In each embodiment, substantially identical components are designated by the same reference numerals, and their description will be omitted. In the following embodiments, the terms "first" and "second" attached to components are merely used to distinguish between similar components, and do not indicate superiority or inferiority between the components. In each drawing, the dimensions of each component may be enlarged as necessary for ease of explanation, and the dimensional ratios between the components may not be the same as in reality.

[0010] (First embodiment) First, a first embodiment of the present invention will be described with reference to FIGS. 1 is for contactlessly supplying power to a load 91 such as a battery or a motor provided in a moving object 90. Hereinafter, the contactless power supply system 1 may be simply referred to as a system 1. The system 1 is made up of a power transmitting device 10 arranged along a travel path along which a plurality of moving objects 90 travel, and a power receiving device 20 mounted on the moving object 90.

[0011] The mobile object 90 can transport parts and the like within, for example, a factory or a logistics facility. The mobile object 90 is, for example, an automated guided vehicle that travels on a moving surface F. Automated guided vehicles include AGVs (Automated Guided Vehicles) that travel automatically along a predetermined travel path, as well as AMRs (Autonomous Mobile Robots) that travel automatically along a travel path that they determine themselves. The moving surface F constitutes a surface that faces the mobile object 90 when the mobile object 90 moves. The longitudinal direction of the mobile object 90 coincides with the direction of movement of the mobile object 90. The mobile object 90 has a housing 901 that forms the outer shell of the mobile object 90 and is made of, for example, metal. The mobile object 90 can be configured with a well-known component, such as a GPS, for acquiring location information of the current location of the mobile object 90.

[0012] The mobile body 90 includes a first mobile body 90a and a second mobile body 90b. The first mobile body 90a is provided with a power receiving device 20. The first mobile body 90a is driven by supplying power to a load 91 using the power transmission and reception caused by magnetic coupling between the power transmission device 10 and the power receiving device 20. In this embodiment, the power transmission device 10 can supply power to a plurality of power receiving devices 20 provided on the plurality of first mobile bodies 90a, respectively. On the other hand, the second mobile body 90b is not provided with a power receiving device 20 and drives autonomously without receiving or transmitting power from the power transmission device 10. The system 1 may also be applied to a linear conveyor that moves a slider, which is a mobile body, along a guide rail. In this case, the power transmission device 10 is provided on the guide rail side, and the power receiving device 20 is provided on the slider.

[0013] The power transmitting device 10 is buried or installed on a moving surface F in at least a part of the moving range of the moving body 90. The power transmitting device 10 supplies high-frequency power to the power receiving device 20 in a contactless manner using magnetic coupling. The power transmitting device 10 is connected to an external power source 2, such as a high-frequency power supply, via, for example, an inverter or a rectifier circuit (not shown). As shown in FIG. 2(a), the power transmitting device 10 has a power transmitting-side resonant circuit 11 configured as an LC resonant circuit. The power transmitting-side resonant circuit 11 includes a power transmitting coil 111 and a power transmitting capacitor 112. The power transmitting coil 111 is configured by insulating a conductor made of a copper foil pattern provided on a substrate made of, for example, a polyimide film. The conductor of the power transmitting coil 111 is not limited to this, and may be configured as a conductor wire.

[0014] The power transmitting device 10 generates AC power at approximately the same frequency as the self-resonant frequency. In this embodiment, the power transmitting device 10 generates high-frequency power corresponding to a high frequency band of 3 MHz to 30 MHz, the so-called HF band. The frequency of the power generated by the power transmitting device 10 is, for example, 13.56 MHz. The specifications of the power transmitting coil 111 and the power transmitting capacitor 112 are set appropriately according to the desired resonant frequency.

[0015] The power receiving device 20 is electrically connected to a load 91 of a mobile object 90 via, for example, a rectifier circuit (not shown). As shown in FIG. 2(a), the power receiving device 20 has a power receiving-side resonant circuit 21 configured as an LC resonant circuit. The power receiving-side resonant circuit 21 has the same resonant frequency as the power transmitting-side resonant circuit 11. As shown in FIG. 2(a), the power receiving-side resonant circuit 21 has a power receiving coil 211 and a power receiving capacitor 212. The power receiving coil 211 is configured by insulating a conductor made of a copper foil pattern provided on a substrate formed of, for example, a polyimide film. The conductor of the power receiving coil 211 is not limited to this, and may be configured, for example, by a conducting wire. The power receiving device 20 generates power when oscillations of a magnetic field generated in the power transmitting coil 111 of the power transmitting device 10 resonate in the power receiving-side resonant circuit 21.

[0016] Here, if the housing 901 of the first moving body 90a is made of metal, it becomes difficult to stably transmit power from the power transmitting device 10 to the power receiving device 20 due to a decrease in power supply efficiency, etc. In this case, it is conceivable to increase the power supply efficiency by providing a soft magnetic material such as ferrite between the housing 901 and the power receiving device 20 to enhance the coupling between the power transmitting coil 111 and the power receiving coil 211.

[0017] However, in a high frequency band such as the HF band, if the inductance on the power receiving device 20 side increases due to a soft magnetic material provided around the power receiving device 20, fluctuations in the inductance on the power transmitting device 10 side become noticeable. For this reason, it is necessary to suppress fluctuations in the inductance on the power transmitting device 10 side by canceling out the inductance on the power receiving device 20 side increased by the soft magnetic material. In addition, it is necessary to prevent fluctuations in the inductance on the power transmitting device 10 side from occurring depending on the presence or absence of a second moving object 90b on which the power receiving device 20 is not mounted within the area where the power transmitting device 10 is installed.

[0018] Therefore, in this embodiment, the system 1 includes a sheet member 30. As shown in FIG. 1 , the sheet member 30 is attached to a facing surface 902 of the moving body 90 that faces the power transmitting device 10. In this case, the facing surface 902 is the bottom surface of the moving body 90. The sheet member 30 is provided on both the first moving body 90a and the second moving body 90b of the moving body 90. In the first moving body 90a, the sheet member 30 is located, for example, between the facing surface 902 and the power receiving coil 211 of the power receiving-side resonant circuit 21.

[0019] The sheet member 30 is formed in a sheet shape, having a generally rectangular shape that is long in the longitudinal direction of the movable body 90. The sheet shape means that the dimension in the thickness direction is smaller than the dimension in the longitudinal direction and the dimension in the short direction perpendicular to the thickness direction and the longitudinal direction. The outer shape of the sheet member 30 is at least larger than the outer shape of the power receiving coil 211.

[0020] As shown in Fig. 2, the sheet member 30 is composed of a first member 31 and a second member 32. The widthwise dimensions of the first member 31 and the second member 32 are substantially the same as the widthwise dimension of the sheet member 30. The sheet member 30 is arranged such that the first members 31 and the second members 32 are aligned in a line along the longitudinal direction of the movable body 90. In this embodiment, the sheet member 30 is arranged such that the first members 31 and the second members 32 are alternately aligned. Note that in Fig. 2 and other figures, the second members 32 are indicated by hatching to clearly distinguish the first members 31 and the second members 32.

[0021] The first member 31 is made of a material having a relative permeability greater than 1 in the high frequency band used. The first member 31 is made of a soft magnetic material such as ferrite. The second member 32 is made of a material having a relative permeability of 1 or less in the high frequency band used. The second member 32 is made of a conductive non-magnetic material such as aluminum, gold, or silver. The second member 32 is intended to cancel out the inductance on the power receiving device 20 side increased by the first member 31. In other words, the sheet member 30 is made of a plurality of materials having different relative permeabilities in the high frequency band used, arranged in a line along the longitudinal direction of the moving body 90.

[0022] 2(b), the power receiving coil 211 is provided on one surface, in this case the lower surface, of the sheet member 30. In the region where the power receiving coil 211 and the first member 31 overlap, a magnetic field M is generated between the power transmitting side resonant circuit 11 and the power receiving side resonant circuit 21, as shown by the dashed line in FIG. 2(a). Therefore, in the first moving body 90a, the sheet member 30 constitutes a part of the power receiving device 20. On the other hand, in the region where the power receiving coil 211 and the second member 32 overlap, the generation of the magnetic field M between the power transmitting side resonant circuit 11 and the power receiving side resonant circuit 21 is suppressed.

[0023] In this way, it is possible to suppress fluctuations in inductance on the power transmission device 10 side due to increases in inductance on the power reception device 20 side, while increasing the coupling between the power transmission coil 111 and the power reception coil 211. Furthermore, by providing the sheet member 30 on the second moving body 90b, it is possible to keep the inductance on the power transmission device 10 side constant, regardless of the presence or absence of the second moving body 90b.

[0024] According to the embodiment described above, the contactless power supply system 1 includes the power transmission device 10 and the sheet member 30. The power transmission device 10 is arranged along a movement path of the mobile object 90, and supplies high-frequency power to the power receiving device 20 in a contactless manner using magnetic coupling. The sheet member 30 can be attached to an opposing surface 902 of the mobile object 90 that faces the power transmission device 10. The sheet member 30 has a first member 31 made of a soft magnetic material and a second member 32 made of a non-magnetic material that are arranged in a line along the movement direction of the mobile object 90.

[0025] According to this, the inductance increased by the first member 31 of the sheet member 30 attached to the moving body 90 can be offset by the second member 32. This makes it possible to keep the inductance of the power transmitting device 10 constant regardless of the presence or absence of the moving body 90. Therefore, the inherent resonance frequency can be maintained, enabling stable power supply.

[0026] The sheet member 30 also constitutes a part of the power receiving device 20. The power receiving device 20 has a power receiving coil 211 provided on one surface of the sheet member 30. This simplifies the configuration of the power receiving device 20 and suppresses fluctuations in inductance of the power transmitting device 10 due to changes in the distance between the power transmitting device 10 and the power receiving device 20, for example.

[0027] The sheet member 30 is arranged such that the first members 31 and the second members 32 are alternately arranged. This makes it possible to reduce the influence of the relative positional relationship of the moving body 90 with respect to the power transmitting device 10 when suppressing fluctuations in inductance of the power transmitting device 10.

[0028] (Second embodiment) Next, a second embodiment will be described with reference to FIG. 3. In this second embodiment, the structure of the sheet member 30 is different from that of the first embodiment. Specifically, in the first embodiment, the sheet member 30 is configured with first members 31 and second members 32 arranged alternately. In contrast, in this embodiment, the sheet member 30 is configured by dividing it into two parts, the first member 31 and the second member 32. In this case, the power receiving coil 211 of the power receiving device 20 provided on the first moving body 90a is provided within the area of ​​the first member 31. In other words, the power receiving coil 211 is not provided within the area of ​​the second member 32.

[0029] The second embodiment can also achieve the same effects as the first embodiment. Furthermore, by providing the power receiving coil 211 in a region corresponding to the first member 31, the power receiving coil 211 can be made smaller. This allows the power receiving device 20 to have an efficient device configuration.

[0030] (Third embodiment) Next, a third embodiment will be described with reference to Fig. 4. In this third embodiment, the direction in which the first member 31 and the second member 32 are aligned differs from that of the first embodiment. In this embodiment, the first member 31 and the second member 32 are aligned in a line along a direction perpendicular to the movement direction of the moving body 90. "Perpendicular to the movement direction" does not necessarily mean completely perpendicular to the movement direction of the moving body 90, but also includes being slightly inclined with respect to the direction perpendicular to the movement direction.

[0031] In this embodiment, the longitudinal dimensions of the first member 31 and the second member 32 match the longitudinal dimension of the sheet member 30. The first member 31 is located at both ends of the sheet member 30 in the width direction. In other words, the second member 32 is not present at both ends of the sheet member 30 in the width direction. In this case, a magnetic field M can be generated between the power transmitting resonant circuit 11 and the power receiving resonant circuit 21 at both ends of the sheet member 30 in the width direction, along the longitudinal direction of the sheet member 30.

[0032] According to the third embodiment, it is possible to achieve the same effects as those of the first embodiment, and it is also possible to stably supply power along the moving direction of the moving object 90 while suppressing fluctuations in inductance on the power transmitting device 10 side.

[0033] As shown in the example of FIG. 5 , the sheet member 30 may be configured with a checkerboard arrangement in which the first members 31 and the second members 32 are alternately arranged along a first movement direction of the moving body 90 and a second movement direction perpendicular to the first movement direction. The alternate arrangement means that the first members 31 and the second members 32 arranged along the first movement direction or the second movement direction of the moving body 90 are staggered. In this manner, even if the path along which the moving body 90 moves includes two directions perpendicular to each other in a plane, it is possible to stably supply power to the moving body 90 moving in each direction while suppressing fluctuations in inductance on the power transmitting device 10 side. Note that in FIG. 5 , for clarity, only some of the first members 31 and second members 32 are denoted by reference numerals, and the reference numerals of the remaining first members 31 and second members 32 are omitted.

[0034] The above-described embodiment is presented as an example and is not intended to limit the scope of the invention. This novel embodiment can be embodied in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. This embodiment and its modifications are included within the scope and spirit of the invention, and are also included in the inventions and their equivalents as defined in the claims. [Explanation of symbols]

[0035] 1... non-contact power supply system, 10... power transmission device, 20... power receiving device, 30... sheet member, 31... first member, 32... second member, 90... moving body, 902... opposing surface

Claims

1. a power transmitting device that is arranged along a moving path of the moving object and that supplies high-frequency power to a power receiving device in a non-contact manner using magnetic coupling; a sheet member that can be attached to an opposing surface of the moving body that faces the power transmission device, The sheet member includes a first member made of a soft magnetic material and a second member made of a non-magnetic material, and the first member and the second member are arranged side by side along at least one of the moving direction of the moving body and a direction perpendicular to the moving direction of the moving body. Contactless power supply system.

2. the sheet member constitutes a part of the power receiving device, The power receiving device has a power receiving coil provided on one surface of the sheet member. The contactless power supply system according to claim 1 .

3. The sheet member is arranged such that the first members and the second members are alternately arranged. The contactless power supply system according to claim 2 .

4. The sheet member is configured by being divided into two parts, the first member and the second member. The contactless power supply system according to claim 2 .

5. A sheet member applied to a contactless power supply system including a power transmission device arranged along a moving path of a moving object, The sheet member is provided on an opposing surface of the moving body that faces the power transmission device, and a first member made of a soft magnetic material and a second member made of a non-magnetic material are formed in a row along at least one direction of the moving direction of the moving body and a direction perpendicular to the moving direction of the moving body. Sheet member.

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