JP7328296B2 - Mobile and optical wireless power supply system - Google Patents

Description

The present invention relates to mobile bodies and optical wireless power supply systems.

In recent years, the electrification of moving bodies and the creation of new electric moving bodies are progressing. In order to extend the moving distance of an electric vehicle, a power supply method for supplying electric power to the electric vehicle is required. Wired power feeding is an example of a power feeding method, but since wired power feeding limits the movement range of an electric vehicle, a wireless power feeding method is desired in order to greatly expand the usability of electric vehicles.

As wireless power feeding methods, an electromagnetic induction method, a magnetic resonance method, an electric field coupling method, a microwave space transmission method, an optical wireless power feeding method, and the like have been known so far. Among these, an "optical wireless power supply system" using a solar cell has attracted attention as a power supply system for electric vehicles.

In the optical wireless power supply system, the use of various light sources has been studied, but it is known that laser light is the most efficient from the viewpoint of photoelectric conversion efficiency.

However, since laser light has high directivity and a narrow beam width, there is a problem that the light is difficult to uniformly hit the entire solar cell that converts the optical energy of the laser light into electrical energy. When only a part of the solar cell, for example, a half or less of the light receiving surface of the solar cell is exposed to light, the power generation efficiency is lower than when the entire solar cell is exposed to light. Therefore, in the optical wireless power supply system using a solar cell, it is necessary that the solar cell is irradiated with a light beam of the same size as the solar cell, that the light intensity distribution of the entire solar cell is uniform, and that the light leaking from the solar cell module less is required.

Until now, as a method of irradiating the entire solar cell with laser light evenly, a fly-eye lens or the like has been used to irradiate light with a certain wide beam width, such as that of a VCSEL (Vertical Cavity Surface Emitting Laser) or an LED. A method of irradiating according to the shape of is reported (for example, Patent Document 1). According to the invention described in Patent Document 1, by providing an optical system including a pair of fly-eye lenses and an imaging lens on the path of a light beam incident on the photoelectric conversion element, uniform light is emitted over the entire surface of the photoelectric conversion element. The beam can be irradiated and the performance of the receiving module can be improved. However, in such a configuration, due to the characteristics of the fly-eye lens, performance cannot be sufficiently exhibited unless the beam width of the light source is wide to some extent, and light with a narrow beam width cannot be applied.

Japanese Patent Application Laid-Open No. 2020-36480

An object of the present invention is to realize a mobile object and an optical wireless power supply system having a light receiving module that enables highly efficient power generation.

A moving object according to an embodiment of the present disclosure includes a photoelectric conversion unit that receives laser light and converts it into electric power, and a diffusion member that is arranged on the light receiving surface side of the photoelectric conversion unit and diffuses and transmits the laser light. a light-receiving unit, a power storage unit storing electric power converted by the photoelectric conversion unit, and a driving unit driving the power unit using the electric power stored in the power storage unit, and the diffusion member is a light-receiving surface of the photoelectric conversion unit. The laser light is diffused so that the laser light having a beam diameter smaller than the length of one side of the photoelectric conversion unit is irradiated on the entire light receiving surface of the photoelectric conversion unit.

In the mobile object according to an embodiment of the present disclosure, the diffusing member is preferably a diffusing lens.

In the mobile object according to an embodiment of the present disclosure, the diffusion member is preferably a diffusion film.

Preferably, the moving body according to an embodiment of the present disclosure further includes a housing that covers the photoelectric conversion section and the diffusion member.

In the mobile object according to an embodiment of the present disclosure, it is preferable that a reflective film is arranged inside the housing.

In the mobile object according to an embodiment of the present disclosure, the reflective film is preferably a metal film.

In the mobile object according to an embodiment of the present disclosure, the metal film preferably contains at least one of aluminum, gold, and silver.

In a moving object according to an embodiment of the present disclosure, an imaging unit that captures an image of a power supply device that emits laser light, a detection unit that detects the power supply device based on the captured image, and face the power supply device. and a control unit for controlling the position of the light receiving unit.

An optical wireless power supply system according to an embodiment of the present disclosure is an optical wireless power supply system that includes a power supply device and a mobile body that receives power from the power supply device, wherein the mobile body receives laser light and receives power. a photoelectric conversion unit that converts into a light-receiving surface of the photoelectric conversion unit, a light-receiving unit that includes a diffusion member that diffuses and transmits laser light, and a power storage unit that stores electric power converted by the photoelectric conversion unit; A driving unit that drives the power unit using electric power stored in the power storage unit, and a communication unit that transmits and receives information to and from the power supply device. The laser light having a beam diameter smaller than the length is diffused so that the entire light-receiving surface of the photoelectric conversion unit is irradiated with the laser light, and the power supply device includes a light source unit that emits the laser light to the moving body, a moving body an imaging unit that captures an image of a target area, a control unit that controls the position at which laser light is emitted based on the image captured by the imaging unit, and a communication unit that transmits and receives information to and from a moving object. Characterized by

In the wireless optical power supply system according to an embodiment of the present disclosure, the target area is preferably the light receiving section.

In the optical wireless power supply system according to an embodiment of the present disclosure, it is preferable that the power supply device further includes an image recognition section that recognizes an image of the light receiving section.

In the wireless optical power supply system according to an embodiment of the present disclosure, the power supply device preferably further includes a detection unit that detects the position of the moving body.

In the wireless optical power supply system according to an embodiment of the present disclosure, it is preferable that the controller controls the direction of the light source by following the position of the mobile object.

ADVANTAGE OF THE INVENTION According to this invention, the mobile body and optical wireless power supply system which have a light receiving module which enables highly efficient electric power generation are realizable.

1 is a diagram for explaining an overview of an optical wireless power feeding system according to an embodiment of the present disclosure; FIG. 1 is a block diagram of a moving body according to Example 1 of the present disclosure; FIG. FIG. 4 is a diagram for explaining how a light receiving unit of a moving body is irradiated with laser light according to the first embodiment of the present disclosure; FIG. 4 is a diagram for explaining a method of calculating a distance between a diffusion member and a photoelectric conversion unit that constitute a light receiving unit of a moving body according to the first embodiment of the present disclosure; FIG. 11 is a diagram for explaining how a light receiving unit of a moving object is irradiated with a laser beam according to the second embodiment of the present disclosure; FIG. 12A is a diagram for explaining how a light receiving portion of a moving body is irradiated with a laser beam according to the second embodiment of the present disclosure, and FIG. , and (b) shows an example in which the laser light is irradiated outward from the center of the diffusion member. FIG. 2 is a block diagram of a power supply device and a moving body that configure an optical wireless power supply system according to an embodiment of the present disclosure; FIG. FIG. 4 is a sequence diagram for explaining the operation of the wireless optical power feeding system according to the embodiment of the present disclosure; FIG. 4 is a diagram for explaining an overview of another example of the wireless optical power supply system according to an embodiment of the present disclosure;

Hereinafter, a mobile body and an optical wireless power supply system according to the present invention will be described with reference to the drawings. However, it should be noted that the technical scope of the present invention is not limited to those embodiments, but extends to the invention described in the claims and equivalents thereof.

First, an outline of an optical wireless power supply system according to an embodiment of the present disclosure will be described. FIG. 1 shows a diagram for explaining an outline of an optical wireless power supply system 300 according to an embodiment of the present disclosure. The optical wireless power supply system 300 has a power supply device 200 and a moving object 100 that receives power from the power supply device 200 . A mobile object (eg, drone) 100 can be charged in the power supply area 400 . The moving object 100 may move to the power supply area 400 and charge when the power for moving the moving object 100 is reduced and charging becomes necessary, or when an instruction to charge is received. The moving body 100 may store the position of the power supply area 400 in advance.

In the power supply area 400, for example, a power supply device 200 provided on a structure 500 such as a steel tower is arranged. The power supply device 200 includes a camera, which is the image capturing unit 22, and captures an image of the moving body 100. When it is determined that the moving body 100 is a power supply target based on the captured image, the light source unit 21 is irradiated with a laser beam L1. A photoelectric conversion unit is provided in the light receiving unit 1 of the moving body 100, and the photoelectric conversion unit converts the received laser light into electric energy, and stores the electric energy in the electric storage unit. The moving object 100 can continue moving using the stored power.

Laser light has high directivity, and even if the distance between the moving body 100 and the power supply device 200 is, for example, several kilometers, the beam diameter (several millimeters) does not increase. On the other hand, the photoelectric conversion unit forming the light receiving unit 1 of the moving body 100 has, for example, a rectangular shape with a side length of several cm to 10 cm. The photoelectric conversion section has a property that the energy conversion efficiency is lowered unless the laser light uniformly hits the entire photoelectric conversion section. Therefore, the light receiving unit 1 of the moving body 100 according to the embodiment of the present disclosure has a configuration such that the photoelectric conversion unit is evenly irradiated with laser light. The configuration of the light receiving section 1 of the moving body 100 will be described below.

[Example 1]
FIG. 2 shows a block diagram of the mobile object 100 according to the first embodiment of the present disclosure. The moving body 100 has a light receiving unit 1, a power storage unit 2, a driving unit 3, an imaging unit 4, a detecting unit 5, a control unit 6, a communication unit 7, and a storage unit 8, and these are connected by a bus 10 .

The light-receiving unit 1 includes a photoelectric conversion unit that receives laser light L1 and converts it into electric power, and a diffusion member that is arranged on the light-receiving surface side of the photoelectric conversion unit and diffuses and transmits the laser light L1. The photoelectric conversion section and diffusion member will be described later.

The power storage unit 2 stores electric power converted by the photoelectric conversion unit. The power storage unit 2 may be a storage battery such as a secondary battery. For example, a lithium ion battery or the like may be used as the storage battery.

Drive unit 3 drives the power plant using the electric power stored in power storage unit 2 . If the mobile object 100 is a drone, the drive unit 3 may be a motor that rotates the rotor blades.

The imaging unit 4 captures an image of the power supply device 200 that emits laser light. For example, a camera may be used as the imaging unit 4 .

The detection unit 5 detects the power supply device 200 based on the image captured by the imaging unit 4 . The detection unit 5 may detect the power supply device 200 included in the image by image recognition. By using image recognition, the moving body 100 can accurately grasp the position of the power supply device 200 .

The control unit 6 controls the position of the light receiving unit 1 of the moving body 100 so as to face the light source unit 21 of the power supply device 200 . In this case, the control unit 6 may control the position of only the light receiving unit 1, or may control the position of the moving body 100 as a whole. The controller 6 may use a microcomputer such as a CPU. The control unit 6 can control the orientation of the light receiving unit 1 by following the position of the power supply device 200 . Therefore, the control unit 6 can track the position of the power supply device 200 even when the relative positions of the power supply device 200 and the moving body 100 fluctuate while the light source unit 21 is emitting laser light. , the laser light emitted from the light source unit 21 can be accurately irradiated to the light receiving unit 1 of the moving body 100 . Tracking here refers to continuing to detect the detected power supply device 200 . The moving body 100 may track the power supply device 200 by any method such as radio waves, image recognition, sensors, or the like.

The communication unit 7 transmits and receives information to and from the power supply device 200 .

The storage unit 8 may be, for example, a semiconductor memory. The storage unit 27 may store position information of the power supply area 400 , identification information regarding the power supply device 200 , and a program for controlling the mobile object 100 .

FIG. 3 shows a diagram for explaining how the light receiving unit 1 of the moving body 100 according to the first embodiment of the present disclosure is irradiated with laser light.

A silicon solar cell may be used for the photoelectric conversion unit 11 . Silicon constituting a silicon solar cell can be used regardless of whether the crystal structure is single crystal, polycrystal, or amorphous. However, it is preferably made of single-crystal silicon in terms of high power conversion efficiency. The photoelectric conversion unit 11 includes solar cells using multi-element compound semiconductors (CIS (Copper Indium Selenium) solar cells, CIGS (Copper Indium Gallium Selenium) solar cells), III-V group multi-junction solar cells (GaAs group solar cells, battery, etc.) may be used.

In the case of silicon solar cells, since the electromotive voltage is about 0.8 V, it is necessary to connect a plurality of cells in series in order to increase the output voltage. When one silicon solar cell is divided into a plurality of cells, it is preferable that each cell has a uniform electromotive voltage, so that each cell is preferably uniformly irradiated with light. Therefore, it is preferable that the photoelectric conversion unit 11 is uniformly irradiated with laser light.

In the case of a silicon solar cell, since the wavelength corresponding to the bandgap of silicon (Si) is approximately 1.1 μm, light is not absorbed unless it has energy equal to or greater than the bandgap energy. Therefore, the wavelength of the irradiated laser light needs to be shorter than the wavelength corresponding to the bandgap. On the other hand, most of the energy of light with a wavelength much shorter than the wavelength corresponding to the bandgap causes heat generation in the silicon solar cell, resulting in a decrease in energy conversion efficiency. Therefore, in the silicon solar cell, considering the energy conversion efficiency, it is preferable that the wavelength of the laser light to be irradiated is about 1 μm, which is slightly shorter than the wavelength of 1.1 μm corresponding to the bandgap of silicon. . In addition, since the laser light with a wavelength of 1 μm has a longer wavelength than the range of visible light, it can be said that it is safe for the human body.

The diffusion member 12 diffuses and transmits the laser light L1 emitted from the light source unit 21 of the power supply device 200 . It is preferable that the laser light (hereinafter also referred to as “diffused light”) L2 diffused by the diffusion member 12 is diffused in a range of approximately the same size as the light receiving surface of the photoelectric conversion section 11 . That is, the diffusing member 12 is arranged such that the laser light L1 having a beam diameter (d) smaller than the length (h) of one side of the light receiving surface of the photoelectric conversion unit 11 irradiates the entire light receiving surface of the photoelectric conversion unit 11. , diffuse the laser light L1. As a result, the entire light receiving surface of the photoelectric conversion unit 11 is irradiated with the diffused light L2.

The width of the laser beam diffused by the diffusing member 12 is determined by the distance between the incident surface of the diffusing member 12 and the light receiving surface of the photoelectric conversion section 11 . FIG. 4 shows a diagram for explaining a method of calculating the distance between the diffusion member 12 and the photoelectric conversion unit 11 that constitute the light receiving unit 1 of the moving body according to the first embodiment of the present disclosure. Assuming that the distance between the incident surface of the diffusing member 12 and the light receiving surface of the photoelectric conversion unit 11 is L, and the diffusion angle is θ, the diffusion range x is calculated by the following formula (1).

ここで、レーザー光Ｌ１の光源発散角は０°としている。例えば、拡散範囲ｘを５０ｍｍとした場合、式（１）より、距離Ｌは４３．１ｍｍと算出される。拡散範囲ｘを光電変換部１１の受光面の１辺の長さｈ以上とする（ｘ≧ｈ）ことにより、拡散光Ｌ２を光電変換部１１の受光面全体に照射させることができる。

Here, the light source divergence angle of the laser light L1 is 0°. For example, if the diffusion range x is 50 mm, the distance L is calculated to be 43.1 mm from Equation (1). By setting the diffusion range x to be equal to or longer than the length h of one side of the light receiving surface of the photoelectric conversion unit 11 (x≧h), the entire light receiving surface of the photoelectric conversion unit 11 can be irradiated with the diffused light L2.

When the laser light L1 passes through the diffusion member 12, it is diffused according to the size of the photoelectric conversion section 11, and the entire photoelectric conversion section 11 is irradiated with the laser light L2, thereby enabling more efficient power supply.

A diffusion lens or a diffusion film can be used for the diffusion member 12 . As a diffusion lens, for example, a Fresnel lens may be used. Since it is sufficient to use one Fresnel lens, the loss of light due to the lens can be minimized compared to the case of using a plurality of lenses.

As the diffusion film, for example, a lens diffusion plate (LSD (Light Shaping Diffuser)), a holographic diffuser, an engineered diffuser, or the like may be used. By using these diffusion films, the intensity profile of the incident light can be controlled and homogenized, and diffused light L2 is generated by widening the laser light L1 with a narrow beam width to the size of the light receiving surface of the photoelectric conversion unit 11. can do.

According to the moving body 100 according to the first embodiment, the diffusion member 12 diffuses the laser light L1 whose beam width is narrower than the size of the photoelectric conversion unit 11, and the entire photoelectric conversion unit 11 can be irradiated with the diffused light L2. Therefore, it is not necessary to match the beam width of the laser light L1 to the size of the photoelectric conversion unit 11. FIG. In addition, since laser light has little light attenuation even when the distance between the power supply device 200 and the moving body 100 is long, highly efficient optical wireless power supply can be performed. Furthermore, by using only one diffusing member 12, optical wireless power feeding can be performed while minimizing loss in the diffusing member 12. FIG.

[Example 2]
Next, a mobile body according to a second embodiment of the present disclosure will be described. FIG. 5 shows a diagram for explaining how laser light is applied to the light-receiving unit of the moving object according to the second embodiment of the present disclosure. FIGS. 6A and 6B are diagrams for explaining how laser light is applied to the light-receiving unit of the moving body according to the second embodiment of the present disclosure. FIG. 6(a) shows an example in which the laser light is irradiated to the center of the diffusion member, and FIG. 6(b) shows an example in which the laser light is irradiated from the center to the outside of the diffusion member. . The light-receiving unit 1′ of the moving object according to the second embodiment differs from the light-receiving unit 1 of the moving object according to the first embodiment in that it further includes a housing 13 that covers the photoelectric conversion unit 11 and the diffusion member 12. be. Since other configurations of the moving object according to the second embodiment are the same as those of the moving object according to the first embodiment, detailed description thereof will be omitted.

A photoelectric conversion unit 11 and a diffusion member 12 are arranged inside the housing 13 . An opening 131 is provided in a part of the housing 13 , and the surface 121 of the diffusion member 12 is arranged in the opening 131 of the housing 13 . Therefore, the laser light L1 incident on the diffusion member 12 is diffused by the diffusion member 12, and the diffused light L2 is incident on the light receiving surface 11S of the photoelectric conversion section 11. FIG.

As shown in FIG. 5, when the laser light L1 is irradiated from the light source unit 21 of the power supply device 200 to the light receiving unit 1′ of the moving body, the laser light L1 is directed in a predetermined direction perpendicular to the surface 121 of the diffusion member 12. is shifted by an angle α. In this case, part of the diffused light (for example, L21 and L22) does not directly enter the light receiving surface 11S of the photoelectric conversion unit 11 but enters the inner wall 13W of the housing 13 . Part of the diffused light (L21, L22) is reflected by the inner wall 13W of the housing 13, and the reflected light (L21', L22') enters the light receiving surface 11S of the photoelectric conversion section 11. FIG. Therefore, in the absence of the housing 13, part of the diffused light (L21, L22) that did not enter the light receiving surface 11S of the photoelectric conversion unit 11 and did not contribute to power generation is reflected by the inner wall 13W of the housing 13. Thus, the reflected light (L21', L22') can be made incident on the light receiving surface 11S of the photoelectric conversion unit 11 to contribute to power generation. By covering the photoelectric conversion unit 11 and the diffusion member 12 with the housing 13 in this way, even when the laser light L1 does not enter the surface 121 of the diffusion member 12 perpendicularly, it is possible to suppress a decrease in power generation efficiency. can.

In order to increase the reflectance of the laser beam incident on the inner wall 13W of the housing 13, it is preferable to dispose the reflecting film 14 inside the housing 13. FIG. The reflective film 14 may be a metal film. The metal film may contain at least one of aluminum, gold and silver.

As in the mobile object according to the second embodiment of the present disclosure, the diffusion member 12 and the photoelectric conversion unit 11 are sealed in the housing 13 made of a reflective material, so that the laser beam protruding from the photoelectric conversion unit 11 is Since the light is reflected inside the housing 13, light loss can be minimized.

FIG. 6A shows an example in which the laser beam L1 enters substantially the center of the diffusion member 12. FIG. Even in such a case, when the distance between the surface 121 of the diffusion member 12 and the light receiving surface 11S of the photoelectric conversion unit 11 is longer than a predetermined distance, the diffused light L2 exceeds the light receiving surface 11S. It may spread. As described above, even when the diffused light L2 spreads from the light receiving surface 11S of the photoelectric conversion unit 11, it is reflected by the reflecting film 14 provided on the inner wall of the housing 13, so that the diffused light spreads from the light receiving surface 11S. A decrease in power generation efficiency can be suppressed by allowing the light L2 to enter the light receiving surface 11S.

FIG. 6B shows an example in which the laser beam L1 is incident on a position offset from the center of the diffusion member 12. FIG. In such a case, even if the distance between the surface 121 of the diffusion member 12 and the light receiving surface 11S of the photoelectric conversion unit 11 is appropriate, the diffused light L2 may spread over the light receiving surface 11S. As described above, even when the diffused light L2 spreads from the light receiving surface 11S of the photoelectric conversion unit 11, it is reflected by the reflecting film 14 provided on the inner wall of the housing 13, so that the diffused light spreads from the light receiving surface 11S. A decrease in power generation efficiency can be suppressed by allowing the light L2 to enter the light receiving surface 11S.

In the moving body 100 according to the second embodiment, even if the tracking accuracy is low, the transmission power hardly changes as long as the laser light is within the diameter of the diffusion member. Therefore, it can be said that the configuration of the light receiving unit 1 of the moving body 100 according to the second embodiment is suitable for tracking.

(Optical wireless power supply system)
Next, an optical wireless power supply system according to an embodiment of the present disclosure will be described. FIG. 7 shows a block diagram of a power supply device and a moving body that configure an optical wireless power supply system according to an embodiment of the present disclosure. The optical wireless power supply system 300 has a power supply device 200 and a moving body 100 that receives power from the power supply device 200 . Since the configuration of the moving body 100 shown in FIG. 7 is the same as the configuration of the moving body 100 (FIG. 2) according to the first embodiment, detailed description thereof will be omitted.

The power supply device 200 includes a light source unit 21 , an imaging unit 22 , a control unit 23 , a communication unit 24 , an image recognition unit 25 , a detection unit 26 and a storage unit 27 . It is connected.

The light source unit 21 emits laser light to the moving body. Various lasers such as a semiconductor laser (LD) and a fiber laser can be used as the light source unit 21 . When the photoelectric conversion unit 11 used in the light receiving unit 1 of the moving body 100 is a silicon solar cell, the laser light emitted by the light source unit 21 may be near-infrared light with a central wavelength of 900 to 1000 nm. However, it is not limited to such an example, and the wavelength of the laser light may be set according to the type of the photoelectric conversion section 11 included in the light receiving section 1 of the moving body 100 . Further, the laser emitted from the light source unit 21 may be focused by a lens or the like so that the beam emitted from the light source unit 21 is parallel light.

The imaging unit 22 images the target area of the moving body 100 . For example, a camera may be used as the imaging unit 22 . The target area may be the light receiving section 1 of the moving body 100 . Alternatively, the target area may be a marker provided on the moving body 100 .

The control unit 23 controls the position from which the laser light L1 is emitted based on the image captured by the image capturing unit 22 . A microcomputer such as a CPU may be used for the control unit 23 . The control unit 23 can control the orientation of the light source unit 21 by following the position of the moving body 100 . Therefore, even if the position of the moving body 100 fluctuates while the light source part 21 is irradiating laser light, the control part 23 tracks the position of the moving body 100 and emits laser light from the light source part 21 . It is possible to accurately irradiate the light receiving portion 1 of the moving body 100 with laser light. Tracking here refers to continuing to detect the detected moving object 100 . The power supply device 200 may track the moving object 100 by any method such as radio wave, image recognition, sensor, or the like.

The communication unit 24 transmits and receives information to and from the mobile object 100 . For example, the communication unit 24 can receive a signal requesting power supply from the mobile object 100 .

The image recognition section 25 recognizes the image of the light receiving section 1 of the moving body 100 . The image recognition unit 25 can determine whether or not the moving body 100 is a power supply target by performing image recognition using the captured image of the light receiving part 1 of the moving body 100 .

The detection unit 26 detects the position of the moving body 100 . The detection unit 26 may detect at least one of the distance to the mobile object 100 and the angle with respect to the mobile object 100 in addition to the position of the mobile object 100 . For the detector 26, a sensor such as LiDAR (Light Detection and Ranging) or radar, or a combination thereof may be used. By using a sensor such as LiDAR, the position of the mobile object 100, the distance from the power supply device 200 to the mobile object 100, and the angle with respect to the mobile object 100 can be accurately detected.

The storage unit 27 may be, for example, a semiconductor memory. The storage unit 27 can store identification information about the mobile object 100 and a program for operating the power supply device 200 .

FIG. 8 shows a sequence diagram for explaining the operation of the optical wireless power supply system according to one embodiment of the present disclosure. First, in step S101, the moving object 100 moves to a nearby power supply area 400 (see FIG. 1) when the remaining charge is low. Alternatively, the mobile object 100 may move to the power supply area 400 when receiving an instruction to charge the mobile object 100 . The position of the power supply area 400 may be stored in advance in the storage unit 8 of the moving body 100 .

Next, in step S<b>102 , the moving body 100 detects the power supply device 200 . The moving body 100 may capture an image of the power supply device 200 using the imaging unit 4, and the detection unit 5 may detect the position of the power supply device 200 based on the captured image.

Next, in step S<b>103 , the moving body 100 controls the direction of the light receiving section 1 . Since the moving body 100 detects the position of the power supply device 200 , the control unit 6 controls the direction of the light reception unit 1 so that the light reception unit 1 faces the position of the power supply device 200 . The control unit 6 may control only the orientation of the light receiving unit 1 without changing the position of the moving body 100 . Alternatively, the control unit 6 may control the driving unit 3 to change the direction of the moving body 100 as a whole so that the light receiving unit 1 faces the power supply device 200 .

Next, in step S<b>104 , the moving body 100 requests power supply from the power supply device 200 . For example, the communication unit 7 of the moving object 100 may request power supply by transmitting a signal requesting power supply to the power supply apparatus 200 . However, when the power supply device 200 detects that the mobile body 100 has entered the power supply area 400, power may be automatically supplied to the mobile body 100. In this case, the mobile body 100 may not request power supply to the power supply apparatus 200 .

Next, in step S<b>105 , the power supply device 200 detects the light receiving section 1 of the moving body 100 . For example, the imaging unit 22 of the power supply device 200 captures an image of the light receiving unit 1 of the moving body 100, the image recognition unit 25 performs image processing based on the captured image, and the detection unit 26 detects the position of the light receiving unit 1. may be detected.

Next, in step S<b>106 , the power supply device 200 controls the direction of the light source section 21 . The control unit 23 of the power supply device 200 may control only the light source unit 21 to direct the direction of the light source unit 21 toward the light receiving unit 1 of the moving body 100. By controlling the direction of the entire power supply device 200 , the direction of the light source unit 21 may be directed toward the light receiving unit 1 of the moving body 100 . Alternatively, the controller 23 may control the direction of the laser light by controlling the angle of a mirror that reflects the laser light.

Next, in step S<b>107 , the power supply device 200 irradiates the moving body 100 with laser light.

Next, in step S108, the laser light hits the diffusion member 12 and is diffused in a circular or rectangular shape.

Next, in step S109, the entire photoelectric conversion unit 11 is irradiated with the diffused light, and the photoelectric conversion unit 11 converts the energy of the laser light into electrical energy. The converted electric energy is stored in the power storage unit 2 .

As described above, optical wireless power feeding to the moving body 100 is performed by the laser light emitted from the light source unit 21 of the power feeding device 200 . Note that when sufficient power is stored in the power storage unit 2 of the moving body 100, the communication unit 7 may notify the power supply device 200 that power supply is completed.

(Modification)
In the above description, a case where the mobile object 100 is a drone has been described as an example, but the mobile object is not limited to flying objects such as drones, and may be mobile objects such as electric vehicles. Here, a case where the moving object is an electric vehicle will be described as an example. FIG. 9 shows a diagram for explaining an overview of another example of the wireless optical power supply system according to an embodiment of the present disclosure.

First, electric vehicle 600 enters power supply area 400 . The electric vehicle 600 receives radio waves emitted by the power supply device 200 installed on the utility pole 700 , grasps the position of the light source section 21 , and controls the orientation of the light receiving section 1 .

After detecting the position of the light receiving unit 1 and controlling the orientation of the light source unit 21 , the power supply device 200 irradiates the light receiving unit 1 with the laser light L<b>1 . As described above, optical wireless power feeding from the power feeding device 200 to the electric vehicle 600 can be executed.

Note that the electric vehicle 600 may be moving in the direction of arrow A, for example, while the power supply device 200 is supplying power to the electric vehicle 600 . Since the power supply device 200 tracks the position of the light receiving unit 1 of the electric vehicle 600, the light receiving unit 1 can be irradiated with the laser light L1 emitted from the light source unit 21 even when the electric vehicle 600 is moving. It's for. In this case, power supply device 200 and electric vehicle 600 may track each other.

1 Light Receiving Unit 2 Power Storage Unit 3 Driving Unit 4 Imaging Unit 5 Detecting Unit 6 Control Unit 7 Communication Unit 8 Storage Unit 11 Photoelectric Conversion Unit 12 Diffusion Member 100 Moving Body 200 Power Supply Device

Claims (11)

a photoelectric conversion unit that receives laser light and converts it into electric power; and a light receiving unit that is disposed on the light receiving surface side of the photoelectric conversion unit and includes a diffusion member that diffuses and transmits the laser light;
a power storage unit that stores electric power converted by the photoelectric conversion unit;
a drive unit that drives a power unit using the electric power stored by the power storage unit;
has
the diffusing member diffuses laser light having a beam diameter smaller than the length of one side of the light receiving surface of the photoelectric conversion unit so that the entire light receiving surface of the photoelectric conversion unit is irradiated with the laser light;
further comprising a housing that covers the photoelectric conversion unit and the diffusion member;
A reflective film is arranged on the inner wall of the housing,
A moving body characterized by: 2. The moving body according to claim 1, wherein said diffusion member is a diffusion lens. 3. The moving body according to claim 1, wherein said diffusion member is a diffusion film. 2. The moving body according to claim 1, wherein said reflective film is a metal film. 5. The moving body according to claim 4, wherein said metal film contains at least one of aluminum, gold and silver. an imaging unit that captures an image of the power supply device that emits the laser light;
a detection unit that detects the power supply device based on the image;
a control unit that controls the position of the light receiving unit so as to face the power supply device;
The moving body according to any one of claims 1 to 5, further comprising: An optical wireless power supply system having a power supply device and a mobile body that receives power from the power supply device,
The moving body is
a photoelectric conversion unit that receives laser light and converts it into electric power; and a light receiving unit that is disposed on the light receiving surface side of the photoelectric conversion unit and includes a diffusion member that diffuses and transmits the laser light;
a power storage unit that stores electric power converted by the photoelectric conversion unit;
a drive unit that drives a power unit using the electric power stored by the power storage unit;
a communication unit that transmits and receives information to and from the power supply device;
has
the diffusing member diffuses laser light having a beam diameter smaller than the length of one side of the light receiving surface of the photoelectric conversion unit so that the entire light receiving surface of the photoelectric conversion unit is irradiated with the laser light;
further comprising a housing that covers the photoelectric conversion unit and the diffusion member;
A reflective film is arranged on the inner wall of the housing,
The power supply device
a light source unit that emits a laser beam to the moving object;
an imaging unit that captures an image of a target area of the moving body;
a control unit that controls a position from which laser light is emitted based on the image captured by the imaging unit;
a communication unit that transmits and receives information to and from the mobile object;
An optical wireless power feeding system characterized by comprising: 8. The optical wireless power feeding system according to claim 7, wherein said target area is said light receiving section. 9. The optical wireless power supply system according to claim 7, wherein said power supply device further has an image recognition section for recognizing an image of said light receiving section. The optical wireless power supply system according to any one of claims 7 to 9, wherein the power supply device further includes a detection unit that detects the position of the moving object. The optical wireless power supply system according to any one of claims 7 to 10, wherein said control unit controls the direction of said light source unit by following the position of said moving object.

Images