WO2021145141A1 - Inspection system and inspection method - Google Patents

Abstract

This inspection system inspects a solar-power-generating device that has an array, and a tracking device that changes the orientation of the array according to the movement of the sun, the inspection system comprising: a flight device, an imaging unit, a calculation unit, and a control unit. The flight device can fly and hover. The imaging unit is provided in the flight device, performs an aerial shoot of the array from a first position, and acquires a first image. The calculation unit calculates orientation information related to the orientation of the array on the basis of the first image. The control unit performs a first flight control that flies the flight device to the first position, and a second flight control that, based on the orientation information, brings the flight device closer to the array than the first position.

Description

Inspection system and inspection method

The present disclosure relates to an inspection system and an inspection method.
This application claims priority based on Japanese Application No. 2020-003552 filed on January 14, 2020, and incorporates all the contents described in the Japanese application.

The condensing type photovoltaic power generation device is a device that generates electricity by condensing sunlight on a power generation element (cell) by a condensing unit including a lens (for example, Patent Document 1). In a concentrating photovoltaic power generation device, if the tracking operation of the array with respect to the sun deviates, the condensing position shifts and power cannot be generated. Therefore, it is necessary to inspect the presence or absence of tracking deviation. Patent Document 1 discloses a technique for obtaining a change in the amount of power generated before and after a tracking operation in a concentrating photovoltaic power generation device and determining whether or not there is a tracking deviation to be corrected based on the change.

Also, in recent years, technology related to flying devices such as drones has been rapidly developing. For example, in Patent Document 2, a sign detected from an aerial image (or a composite image of a plurality of aerial images) obtained by performing aerial photography at each position on a predetermined aerial image path using an unmanned aerial vehicle is to be collected. A technique for collecting a cargo when it is determined that the sign corresponds to the luggage of the vehicle is disclosed.

Patent Document 3 discloses a technique for controlling the flight position or flight route of a flying object using a flying object guiding sheet. Patent Documents 4 and 5 disclose a technique related to delivery using a drone.

Japanese Unexamined Patent Publication No. 2015-22340 Japanese Unexamined Patent Publication No. 2019-6356 Japanese Unexamined Patent Publication No. 2018-12208 Japanese Unexamined Patent Publication No. 2019-131332 Japanese Unexamined Patent Publication No. 2018-51279

The inspection system of the present disclosure is an inspection system that inspects a solar power generation device having an array and a tracking device that changes the attitude of the array with the movement of the sun, and includes a flight device, an imaging unit, and an image pickup unit. The flight device includes a calculation unit and a control unit, and the flight device can fly and stand still in the air. The image pickup unit is provided in the flight device, and the array is aerial photographed from a first position to obtain a first image. Is acquired, the calculation unit calculates attitude information regarding the attitude of the array based on the first image, and the control unit has a first flight control for flying the flight device to the first position, and the above. This is an inspection system that performs a second flight control that brings the flight device closer to the array than the first position based on the attitude information.

The inspection method of the present disclosure is an inspection method for inspecting a photovoltaic power generation device having an array for tracking the sun, the first moving step of flying the flight device having an image pickup unit to a first position, and the first position. Based on the image obtained by aerial photography of the array by the imaging unit, the calculation step of calculating the attitude information regarding the attitude of the array, and based on the attitude information, the flight device is moved from the first position. An inspection including a second moving step of approaching the array and, after the second moving step, an inspection step of inspecting the photovoltaic power generation device by the flying device from a position closer to the array than the first position. The method.

It is explanatory drawing which shows the inspection system which concerns on this embodiment. It is a perspective view which looked at the condensing type photovoltaic power generation apparatus in a completed state which concerns on embodiment from the light receiving surface side. It is a perspective view which looked at the condensing type photovoltaic power generation apparatus in the state of being assembled which concerns on embodiment from the light receiving surface side. It is a perspective view which shows the structure of the condensing type photovoltaic power generation module which concerns on embodiment. It is sectional drawing which shows the structure of the light receiving part which concerns on embodiment. It is sectional drawing which shows the structure of the condensing type photovoltaic power generation unit which concerns on embodiment. It is explanatory drawing which shows the schematic structure of the flight apparatus which concerns on this embodiment. It is a block diagram which shows typically the functional structure of the inspection system which concerns on this embodiment. It is a flowchart which shows the procedure of the inspection method which concerns on this Embodiment. It is explanatory drawing which shows roughly the positional relationship between the flight apparatus and the solar power generation apparatus at the end of the 1st moving process. It is explanatory drawing which shows an example of a 1st image and a model image. It is explanatory drawing which shows an example of the 1st image and the model image when the tracking of an array is deviated. It is explanatory drawing which shows an example of the 1st image at the time of misalignment of a flight apparatus. It is explanatory drawing which shows roughly the positional relationship between the flight apparatus and the solar power generation apparatus at the end of the 2nd moving process. It is explanatory drawing which shows how the flight apparatus scans an array along the path P1. It is explanatory drawing which shows the mode that the flight apparatus inspects an array at the position P2 on the upstream side of the path P1 shown in FIG. It is explanatory drawing which shows the mode that the flight apparatus inspects an array at the position P3 on the downstream side of the path P1 shown in FIG. It is a block diagram which shows typically the functional structure of the inspection system which concerns on 1st modification. It is explanatory drawing which shows the flight apparatus and the solar power generation apparatus which concerns on the inspection system which concerns on 2nd modification. It is a block diagram which shows typically the functional structure of the inspection system which concerns on the 2nd modification. It is a perspective view which shows the structure of the module which has the shielding plate which concerns on 3rd modification. It is explanatory drawing which shows the state of the 1st moving process which concerns on 4th modification.

[Problems to be solved by the invention]
In a photovoltaic power generation system, a plurality of (for example, 100 or more) photovoltaic power generation devices that perform a tracking operation may be arranged on a vast site. As the number of photovoltaic power generation devices included in the photovoltaic power generation system increases, the total amount of power generation increases, but there is also a problem that the management burden such as maintenance and inspection increases.

For example, using the technique according to Patent Document 1, it is possible to determine the presence or absence of tracking deviation in the photovoltaic power generation device based on the change in the amount of power generation before and after the tracking operation, but it is possible to know the cause of the tracking deviation. For that purpose, the manager needs to visually inspect the photovoltaic power generation device.

Here, it is conceivable to perform an inspection by taking an aerial photograph of the solar power generation device using a flight device such as a drone. For example, in the case of a fixed-type photovoltaic power generation device that does not track the sun, the attitude of the array does not change, so the flight route of the flight device does not change either. Therefore, the aerial photography technique using the conventional flight device can be directly applied to the inspection of the fixed type photovoltaic power generation device. However, in the case of a photovoltaic power generation device that performs a sun tracking operation, the attitude of the array changes depending on the season and time, so conventional aerial photography technology cannot perform a precise inspection of the photovoltaic power generation device that performs a tracking operation. ..

In view of such issues, the purpose of the present disclosure is to reduce the management burden on the maintenance and inspection of the photovoltaic power generation device in the inspection system and the inspection method for inspecting the photovoltaic power generation device.

[Effect of the invention]
According to the present disclosure, it is possible to reduce the management burden on the maintenance and inspection of the photovoltaic power generation device.

[Explanation of Embodiments of the present disclosure]
The embodiments of the present disclosure include at least the following as a gist thereof.
(1) The inspection system of the present disclosure is an inspection system that inspects a solar power generation device having an array and a tracking device that changes the attitude of the array with the movement of the sun, and is an inspection system that inspects a flight device and an image pickup system. A unit, a calculation unit, and a control unit are provided, the flight device can fly and stand still in the air, and the image pickup unit is provided in the flight device to take an aerial photograph of the array from a first position. The first image is acquired, the calculation unit calculates attitude information regarding the attitude of the array based on the first image, and the control unit controls the first flight to fly the flight device to the first position. And, based on the attitude information, it is an inspection system that performs a second flight control that brings the flight device closer to the array than the first position.

According to such a configuration, the control unit performs the first flight control for flying the flight device to the first position and the second flight control for bringing the flight device closer to the array than the first position based on the attitude information. .. This makes it possible to inspect the array from a closer position while avoiding collisions between the array and the flight device, even if the attitude of the array changes with the movement of the sun. The flight device flies when the control unit issues an operation command based on various information. That is, so-called automatic flight is performed. Therefore, the manager of the photovoltaic power generation device does not need to control the flight of the flight device by a remote controller or the like, and the manager only gives an instruction to start the inspection and brings the flight device closer to the array for the inspection. be able to. Therefore, it is possible to reduce the management burden on the maintenance and inspection of the photovoltaic power generation device.

(2) Preferably, the attitude information includes plane information about the plane to which the array belongs, and the second flight control moves the flight device between the first position and the plane based on the plane information. Includes control to position. According to such a configuration, since the flight device is brought close to the array based on the plane information, the array can be inspected from a closer position while avoiding a collision between the array and the flight device.

(3) Preferably, the calculation unit extracts a plurality of first feature units from the array captured in the first image, extracts a second feature portion from the immovable portion captured in the first image, and then extracts the second feature unit. The plane information is calculated based on the coordinates of the plurality of first feature portions, the coordinates of the second feature portion, and the size of the array. According to such a configuration, the plane information can be calculated by a total of three or more feature portions including the plurality of first feature portions and the second feature portion.

(4) Preferably, the immovable portion is a portion of the tracking device located on the same plane as the array. According to such a configuration, since the immovable portion for extracting the second feature portion is located on the same plane as the array, the plane information can be acquired more accurately.

(5) Preferably, the first feature portion is a first mark provided on the array. According to such a configuration, the first feature portion can be extracted more accurately regardless of the imaging conditions for acquiring the first image.

(6) Preferably, the array has a plurality of modules, and the module includes a light receiving unit including a power generating element, a light collecting unit that collects sunlight on the light receiving unit, and the light receiving unit and the collecting unit. It has a shielding portion that is provided between the light portion and shields sunlight that does not collect light on the light receiving portion, and the first mark is provided on the surface of the shielding portion on the light collecting portion side. .. According to such a configuration, since the first mark is provided at a position that does not block the sunlight collected on the light receiving portion, it is possible to acquire the plane information more accurately while maintaining the power generation performance in the light receiving portion. can.

(7) Preferably, the second feature portion is a second mark provided on the immovable portion, and at least one of the shape and color of the second mark is different from the first mark. According to such a configuration, the first mark and the second mark can be easily distinguished in the first image, so that the plane information can be acquired more accurately.

(8) Preferably, the first position is located above the portion that is the center of the change in the posture of the array in the vertical direction. According to such a configuration, it is not necessary to predict the attitude of the array when positioning the flight device at the first position, and the processing load in the calculation unit can be reduced.

(9) Preferably, the calculation unit calculates deviation information indicating whether or not there is a deviation in the tracking of the array based on the attitude information, and the control unit does not have the deviation from the calculation unit. When the deviation information indicating that is output, the second flight control is performed based on the attitude information. With such a configuration, the flight device can be brought closer to the array while more reliably avoiding an unexpected collision between the flight device and the array.

(10) Preferably, the attitude information includes normal information about the normal of the array, and the second flight control sets the flight device along the normal based on the normal information. Includes a third flight control that brings it closer to. With such a configuration, the flight device is brought closer to the array along the normal of the array, so that the flight device can be brought closer to the array while more reliably avoiding an unexpected collision with the array.

(11) Preferably, the calculation unit calculates the current attitude information regarding the attitude of the array at the current time based on the attitude information and the current time, and the control unit calculates the current attitude information regarding the attitude of the array at the current time, and the control unit performs the above after the second flight control. Based on the current attitude information, the fourth flight control for flying the flight device in the direction along the array is performed, and the imaging unit empties the solar power generation device while the control unit performs the fourth flight control. Take a picture and acquire a plurality of second images. According to such a configuration, the flight device can take aerial shots of a plurality of second images while flying in the direction along the array while keeping the distance from the array constant.

(12) Preferably, an inspection unit for inspecting whether or not there is an abnormality in the photovoltaic power generation device is further provided based on the plurality of second images. According to such a configuration, since the inspection is performed based on a plurality of second images taken aerial while keeping the distance from the array constant, various comparative inspections using the second images become easy. A more accurate inspection can be performed.

(13) The inspection method of the present disclosure is an inspection method for inspecting a photovoltaic power generation device having an array for tracking the sun, the first moving step of flying the flight device having an imaging unit to a first position, and the above-mentioned. A calculation step of calculating attitude information regarding the attitude of the array based on an image obtained by aerial photography of the array by the imaging unit from the first position, and the first flight device based on the attitude information. A second moving step of moving closer to the array than the position, and an inspection step of inspecting the photovoltaic power generation device by the flying device from a position closer to the array than the first position after the second moving step. It is an inspection method to prepare.

According to such a configuration, a first moving step of flying the flight device to the first position and a second moving step of bringing the flight device closer to the array than the first position based on the attitude information are performed. This makes it possible to inspect the array from a closer position while avoiding collisions between the array and the flight device, even if the attitude of the array changes with the movement of the sun. In the second moving step, the flight device approaches the array based on the attitude information. That is, the flight device performs so-called automatic flight. Therefore, the manager of the photovoltaic power generation device does not need to control the flight of the flight device by a remote controller or the like, and the manager only gives an instruction to start the inspection and brings the flight device closer to the array for the inspection. be able to. Therefore, it is possible to reduce the management burden on the maintenance and inspection of the photovoltaic power generation device.

[Details of Embodiments of the present disclosure]
Hereinafter, specific examples of the inspection system and inspection method of the present disclosure will be described with reference to the drawings.

<< Main configuration of inspection system >>
FIG. 1 is an explanatory diagram showing an inspection system 1 according to the present embodiment. The inspection system 1 is an inspection system that inspects a plurality of (for example, 100) photovoltaic power generation devices 100, and includes a flight device 4 and a management device 6. Although two solar power generation devices 100a and 100b are typically shown in FIG. 1, a larger number of solar power generation devices 100 actually exist. In the present embodiment, the photovoltaic power generation device 100 is a concentrating photovoltaic power generation device that performs two-axis tracking as described later, but may be a photovoltaic power generation device that performs one-axis tracking.
<< Configuration of photovoltaic power generation equipment >>
2 and 3 are perspective views of one example of the photovoltaic power generation device 100 as viewed from the light receiving surface side, respectively. FIG. 2 shows the photovoltaic power generation device 100 in the completed state, and FIG. 3 shows the photovoltaic power generation device 100 in the state of being assembled. FIG. 3 shows the state in which the skeleton of the tracking mount 25 can be seen in the right half, and the state in which the photovoltaic power generation module (hereinafter, also simply referred to as “module”) 1M is attached is shown in the left half. When actually attaching the module 1M to the tracking pedestal 25, the tracking pedestal 25 is attached while lying on the ground.

Refer to Fig. 2. The photovoltaic power generation device 100 supports an array 10 which is continuous on the upper side and is divided into left and right on the lower side to form a planar light receiving surface as a whole, and supports the array 10 so that the posture of the array 10 (light receiving surface) is changed to that of the sun. It is provided with a tracking device 2 that changes with movement. The array 10 is configured by arranging the modules 1M on the tracking mount 25 (FIG. 3) on the back side. In the example of FIG. 2, the array 10 is an aggregate of 200 modules 1M in total, consisting of (96 (= 12 × 8) × 2) pieces constituting the left and right wings and 8 pieces in the central crossover portion. It is configured.

The tracking device 2 includes a support column 21, a foundation 22, a drive unit 23, a horizontal axis 24 (FIG. 3) as a drive axis, and a tracking stand 25. The lower end of the support column 21 is fixed to the foundation 22, and the upper end is provided with a drive unit 23.

The foundation 22 is firmly buried in the ground so that only the upper surface can be seen. With the foundation 22 buried in the ground, the columns 21 are vertical and the horizontal axis 24 (FIG. 3) is horizontal. With the horizontal shaft 24 inserted, the drive unit 23 has an azimuth angle (angle with the support column 21 as the central axis) and an elevation angle of the horizontal shaft 24 by a drive mechanism (for example, a motor) provided inside the drive unit 23. It can be rotated in two directions (an angle with the horizontal axis 24 as the central axis). That is, the array 10 is a biaxial tracking type array that tracks the sun in two directions, an azimuth angle and an elevation angle, by the tracking device 2.

As shown in FIG. 3, a reinforcing material 25a for reinforcing the tracking mount 25 is attached to the horizontal shaft 24. Further, a plurality of horizontal rails 25b are attached to the reinforcing member 25a. The module 1M is attached so as to fit into the rail 25b. If the horizontal axis 24 rotates in the direction of the azimuth or elevation, the array 10 also rotates in that direction.

As shown in FIG. 2, the light receiving surface of the array 10 usually follows the vertical direction before dawn and sunset. During the daytime, the drive unit 23 operates so that the light receiving surface of the array 10 always faces the sun, and the array 10 performs the tracking operation of the sun.

Array 10 has four first marks 15a, 15b, 15c, 15d. The respective first marks 15a, 15b, 15c and 15d are simply referred to as "first mark 15" unless otherwise specified. The first mark 15 is provided on the surface 12a of the condensing unit 12, which will be described later, in the array 10. In this embodiment, the four first marks 15 are arranged at the corners of the array 10. In FIG. 2, the upper left corner is the first mark 15a, the lower left corner is the first mark 15b, the upper right corner is the first mark 15c, and the lower right corner is the first mark 15d. The number of the first marks 15 is not limited to four, and for example, only two of the first marks 15a and 15c may be provided. Two or more first marks 15 may be provided on the light receiving surface of the array 10.

The shape of the first mark 15 is not particularly limited as long as the center of the mark can be easily identified. In the present embodiment, the shape of the first mark 15 is a shape obtained by adding a ring shape and a cross shape, as typically shown in the first mark 15c of FIG. However, the shape of the first mark 15 may be a simple ring shape, a circular shape, or a polygonal shape. The color of the first mark 15 is also not particularly limited as long as it is a color that makes it easy to identify the mark in the image acquired by the imaging unit 43 described later. In the present embodiment, the color of the first mark 15 is red.

The tracking device 2 has one second mark 16. The second mark 16 is provided on an immovable portion of the tracking device 2 whose position does not change significantly with a change in the posture of the array 10. Specifically, the second mark 16 is provided on a portion of the tracking device 2 located on the same plane as the array 10 (light receiving surface). More specifically, as shown in FIG. 2, the second mark 16 is provided on a portion of the outer peripheral portion of the drive unit 23 that faces the same direction as the array 10. Even if the posture of the array 10 is changed by the tracking device 2, the spatial position (that is, the height and the horizontal position) of the portion of the drive unit 23 does not change significantly, and is always located on the same plane as the array 10. .. In other words, the second mark 16 is provided at the portion of the drive unit 23 that is the center of the change in the posture of the array 10.

In the present embodiment, the shape and color of the second mark 16 are the same as those of the first mark 15. However, the second mark 16 may have a different shape and color from the first mark 15 as in the modified example described later.

<< Configuration example of photovoltaic power generation module >>
FIG. 4 is a perspective view showing the configuration of the module 1M according to the present embodiment. In FIG. 4, only the flexible printed wiring board 13 is shown on the bottom surface 11b side of the housing 11, and other components (light receiving unit 3, etc.) are omitted.

The module 1M includes, for example, a rectangular flat-bottomed container-shaped housing 11 made of metal or resin, a plurality of light receiving portions 3 (see FIG. 5) provided on the bottom surface 11b of the housing 11, and an upper portion of the housing 11. It includes a rectangular condensing unit 12 that can be attached like a lid.

The housing 11 has a bottom plate 111 which is a rectangular flat plate, and a frame 112 provided on the peripheral edge of the bottom plate 111. The surface of the bottom plate 111 that faces the light collecting portion 12 is the bottom surface 11b. A support portion that comes into contact with the light collecting portion 12 is provided on the upper portion of the frame body 112, and the frame body 112 supports the light collecting portion 12 upward by the support portion. On the bottom surface 11b, for example, in each of the left half and the right half of the housing 11, one elongated flexible printed wiring board 13 is arranged so as to be aligned while changing the direction as shown in the drawing. The flexible printed wiring board 13 has a relatively wide portion and a narrow portion. The cell 34 (see FIG. 5) included in the light receiving unit 3 is mounted on a wide portion.

The light collecting unit 12 has a glass plate and a plurality of resin-made Fresnel lenses 12f. The glass plate and the Fresnel lens 12f mainly transmit light having a wavelength of 300 nm to 2800 nm in sunlight. The light collecting unit 12 has a front surface 12a facing the direction of the sun and a back surface 12b located on the opposite side of the surface 12a and facing the direction of the plurality of light receiving units 3.

The plurality of Fresnel lenses 12f are provided on the back surface 12b. For example, each of the illustrated square regions (14 × 10 in the present embodiment, but the quantity is only an example) is a region having one Fresnel lens 12f. Each of the plurality of regions can converge the sunlight to the focal position. It should be noted that the grid-like dotted lines are lines for convenience for expressing the area, and it is not necessary that such a partition line actually exists.

A shielding plate 14 is attached between the flexible printed wiring board 13 and the condensing unit 12. In this embodiment, the shielding plate 14 is made of metal. The shielding plate 14 is formed with a square (or circular) opening 14a similar to the square of the Fresnel lens 12f at a position corresponding to the center of each Fresnel lens 12f. If the array 10 accurately tracks the sun and the angle of incidence of the sunlight on the module 1M is 0 degrees, the light collected by the Fresnel lens 12f passes through the aperture 14a and is incident on the light receiving unit 3. When the tracking is significantly deviated, the collected light is shielded by the shielding plate 14. That is, the shielding plate 14 has a function of shielding sunlight that does not collect light on the light receiving unit 3. However, if the tracking deviation is slight, the focused light passes through the opening 14a.

<< Configuration example of the light receiving part >>
FIG. 5 is a cross-sectional view showing a configuration example of the light receiving unit 3 of the condensing type photovoltaic power generation module. It should be noted that each part shown in FIG. 5 is enlarged as appropriate for the convenience of structural explanation, and is not necessarily a view proportional to the actual dimensions (the same applies to the drawings after FIG. 6).

In FIG. 5, the light receiving portion 3 includes a ball lens 30, a protective plate 31, a support portion 32, a package 33, a cell 34, a lead frame 35 on the P side, a gold wire 36, a lead frame 37 on the N side, and a sealing portion 38. I have. The light receiving unit 3 is mounted on the flexible printed wiring board 13. A bypass diode is connected in parallel to the cell 34, but the illustration is omitted here.

The ball lens 30 is supported by the inner peripheral edge 31e of the upper end portion of the protective plate 31 mounted on the support portion 32 so that a gap in the optical axis Ax direction is formed between the ball lens 30 and the cell 34. The protective plate 31 is, for example, a metal washer. The support portion 32 is, for example, cylindrical and made of resin. The support portion 32 is fixed on the flat package 33. The package 33 is made of resin and holds the cell 34 and the lead frames 35 and 37. The cell 34 is a power generation element that converts light energy into electromotive force, and includes a semiconductor having a PN junction. The output of the cell 34 is drawn out to the lead frame 35 on the P side and to the lead frame 37 via the gold wire 36 on the N side. The sealing portion 38 is a light-transmitting silicone resin, and is provided so as to fill the space formed between the ball lens 30 and the cell 34 inside the protective plate 31 and the support portion 32.

<< Configuration example of concentrating solar power generation unit >>
FIG. 6 is a cross-sectional view showing an example of a condensing photovoltaic power generation unit (hereinafter, appropriately referred to as a “unit”) 1U as a basic configuration of an optical system constituting the module 1M. FIG. 6 shows a state in which the unit 1U faces the sun as the array 10 tracks the sun, and the angle of incidence of the sunlight on the unit 1U is 0 degrees. In this state, the ball lens 30 and the cell 34 of the light receiving unit 3 are on the optical axis Ax of the Fresnel lens 12f, and the light collected by the Fresnel lens 12f passes through the opening 14a of the shielding plate 14 and the ball of the light receiving unit 3. It is taken into the lens 30 and guided to the cell 34. That is, the plurality of Fresnel lenses 12f are arranged in a state where each of the plurality of light receiving portions 3 and the optical axis Ax are aligned with each other.

<< Details of flight equipment >>
FIG. 7 is an explanatory diagram showing a schematic configuration of the flight device 4 according to the present embodiment. The flight device 4 in this embodiment is an unmanned flying robot called a drone. The flight device 4 may be a small unmanned helicopter. The flight device 4 has a main body 41 and a drive unit 42. The flight device 4 includes an imaging unit 43, a position information acquisition unit 44, a control unit 45, a storage unit 46, and a communication unit 47.

The main body 41 includes a resin or metal frame. The drive unit 42 includes a plurality of (for example, four) propeller units 421, an arm unit 422 that changes the line-of-sight direction D1 of the image pickup unit 43, and an irradiation unit 423 that irradiates a laser. The propeller unit 421 can rotate or drive the flight device 4 to fly or stand still in the air (hovering). The propeller unit 421, the arm unit 422, and the irradiation unit 423 are electrically connected to the control unit 45, respectively.

The image pickup unit 43 is a camera that acquires an image, and is, for example, a two-dimensional image sensor using a CCD (Charge-Coupled Device) or a CMOS (Complementary Metal-Oxide Sensor). The imaging unit 43 according to the present embodiment is a color camera that acquires a color image of two or more colors, but may be a monochrome camera that acquires a monochrome image of only one color. The imaging unit 43 has a function of photographing the array 10 from the air (that is, taking an aerial image) and acquiring various images by an inspection method described later.

The position information acquisition unit 44 is, for example, a GPS (Global Positioning System) receiver, and has a function of acquiring position information (for example, a GPS signal) related to the position of the flight device 4. The position information acquisition unit 44 is not limited to the GPS receiver, and may be a signal receiver that receives signals transmitted from a plurality of base stations installed on the ground as position information.

FIG. 8 is a block diagram schematically showing the functional configuration of the inspection system 1 according to the present embodiment. The control unit 45 is electrically connected to each unit of the flight device 4 (drive unit 42, image pickup unit 43, and position information acquisition unit 44), and outputs an operation command to each unit of the flight device 4. In particular, the control unit 45 controls the flight of the flight device 4 by outputting a predetermined operation command to the propeller unit 421. In addition, signals transmitted from each unit of the flight device 4 are input to the control unit 45. The control unit 45 is composed of a computer having a calculation unit and a storage unit.

The control unit 45 has a clock inside. With the clock, the control unit 45 acquires information about the current time. The control unit 45 may be configured to acquire information on the current time from the outside without having a clock inside. For example, information on the current time may be acquired based on the time information included in the GPS signal acquired by the position information acquisition unit 44.

The storage unit 46 has a function of electrically connecting to the control unit 45 and storing information input by the control unit 45. The storage unit 46 is, for example, a non-volatile memory, and more specifically, an SD memory card. The information input from the control unit 45 to the storage unit 46 includes an image acquired by the imaging unit 43 and position information acquired by the position information acquisition unit 44.

The communication unit 47 is electrically connected to the control unit 45, and transmits / receives information by wireless communication with the communication unit 65 of the management device 6 described later. The communication unit 47 transmits the information input by the control unit 45 to the management device 6, and outputs the information received from the communication unit 65 to the control unit 45.

<< Details of management device >>
See FIG. The management device 6 is a device that manages the overall control of the inspection system 1, and is located in a place away from the plurality of photovoltaic power generation devices 100 (for example, in the building of the management building that manages the plurality of photovoltaic power generation devices 100). It is provided. The management device 6 includes a control unit 61, an input unit 62, a display unit 63, a storage unit 64, a communication unit 65, and a reading unit 66. The control unit 61 is electrically connected to the input unit 62, the display unit 63, the storage unit 64, the communication unit 65, and the reading unit 66, respectively. The control unit 61 has a calculation unit 611 and an inspection unit 612. The control unit 61 is composed of a computer having a calculation unit and a storage unit, and the computer operates according to a program to realize functions as a calculation unit 611 and an inspection unit 612, respectively.

The input unit 62 is a device for the administrator to input various settings of the inspection system 1, for example, a mouse and a keyboard. The information input to the input unit 62 is output to the control unit 61. The display unit 63 is a device for displaying information about the inspection system 1, for example, a display. The display unit 63 may have a speaker in addition to the display, and may generate an alarm sound from the speaker when an abnormality of the photovoltaic power generation device 100 is detected by an inspection method described later.

The storage unit 64 has a function of storing information input by the control unit 61. Further, the storage unit 64 stores a program 641 for executing the inspection method described later. The storage unit 64 is, for example, an HDD (Hard Disk Drive) or an SSD (Solid State Drive). The information input from the control unit 61 to the storage unit 64 includes an image acquired by the imaging unit 43, position information acquired by the position information acquisition unit 44, and information regarding the size (for example, design dimensions) of the array 10. , Information about the shapes of the first mark 15 and the second mark 16.

The communication unit 65 transmits / receives information by wireless communication with the communication unit 47 mounted on the flight device 4. The communication unit 65 transmits the information input by the control unit 61 to the communication unit 47, and outputs the information received from the communication unit 47 to the control unit 61. Further, the communication unit 65 transmits / receives information to / from the photovoltaic power generation device 100 by wireless communication or wired communication. The communication unit 65 transmits the information input by the control unit 61 to the photovoltaic power generation device 100. As a result, the management device 6 controls the photovoltaic power generation device 100.

The reading unit 66 reads information from a computer-readable recording medium 661 (for example, an optical disk, a magnetic disk, etc.). The information read from the reading unit 66 is stored in the storage unit 64 via the control unit 61. The program 641 is read from the recording medium 661 via the reading unit 66 and stored in the storage unit 64 before the execution of the inspection method described later.

The calculation unit 611 calculates the posture information regarding the posture of the array 10 based on the image captured by the image pickup unit 43. The inspection unit 612 inspects whether or not there is an abnormality in the photovoltaic power generation device 100 based on the image captured by the imaging unit 43. Details of the calculation unit 611 and the inspection unit 612 will be described later.

<< Inspection method by inspection system >>
Next, an inspection method of the photovoltaic power generation device 100 by the above inspection system 1 will be described. FIG. 9 is a flowchart showing the procedure of the inspection method according to the present embodiment. In the present embodiment, when the administrator of the photovoltaic power generation device 100 gives an instruction to execute the inspection method using the input unit 62, the program 641 is read out by the control unit 61, and the inspection method is started based on the program 641. Will be done.

In the inspection method according to the present embodiment, the takeoff step S101 is first executed. At the time when the takeoff step S101 is started, as shown in FIG. 1, the flight device 4 stands by at the position (X1, Y1, Z1) without flying. The position information regarding the positions of the plurality of photovoltaic power generation devices 100 (for example, the information regarding the positions (Xa, Ya, Za) of the second mark 16 in the drive unit 23 of the photovoltaic power generation device 100a) is stored in advance in the storage unit of the management device 6. It is stored in 64.

When the takeoff step S101 is started, the control unit 61 issues an operation command to the control unit 45 via the communication units 65 and 47, and then the control unit 45 issues an operation command to the drive unit 42. The flight device 4 starts flying and rises to a predetermined height (for example, a height of 10 m or more and 500 m or less).

Next, the first movement step S102 for flying the flight device 4 to the first position is executed. When the first moving step S102 is started, the position information of the photovoltaic power generation device 100 (for example, the photovoltaic power generation device 100a) to be inspected is transmitted from the management device 6 to the control unit 45. Next, the control unit 45 predicts the orientation (optical axis Ax) of the array 10 at the current time based on the position information of the photovoltaic power generation device 100 and the current time. Then, a position separated from the array 10 by a first distance L11 on the predicted optical axis Ax is calculated as the first position.

Finally, the control unit 45 performs the first flight control for flying the flight device 4 to the first position based on the position information of the flight device 4 by the position information acquisition unit 44 and the information regarding the first position. Further, the control unit 45 directs the line-of-sight direction D1 of the image pickup unit 43 in a direction parallel to the predicted optical axis Ax by the arm unit 422. As a result, the first moving step S102 is completed.

FIG. 10 is an explanatory diagram schematically showing the positional relationship between the flight device 4 and the photovoltaic power generation device 100 at the end of the first moving step S102. In this embodiment, the first position is located between the sun 9 and the array 10. In FIG. 10, since the case where there is no tracking deviation in the array 10 (that is, the case where the predicted optical axis Ax and the actual optical axis Ax are in the same direction) is illustrated, the line-of-sight direction D1 of the imaging unit 43 and the actual optical axis Ax are illustrated. The optical axis Ax has a parallel relationship. However, when the array 10 has a tracking deviation, the line-of-sight direction D1 and the actual optical axis Ax are in a non-parallel relationship.

The first distance L11 is a distance such that the flight device 4 does not come into contact with the array 10 in consideration of the deviation of the flight position of the flight device 4 and the deviation of the tracking of the array 10. The first distance L11 is, for example, a distance (L11 = L12 + L13) obtained by adding the maximum deviation amount L12 of the array 10 and the maximum deviation amount L13 of the flight position of the flight device 4.

The maximum deviation amount L12 of the array 10 is the distance from the central portion of the change in the posture of the array 10 (drive unit 23 in this embodiment) to the farthest end of the array 10 (drive unit 23 in this embodiment). The distance from the first mark 15b to the corner where the first mark 15b or 15d is located), which corresponds to the distance reached by the array 10 when the tracking deviation is the largest. The maximum deviation amount L13 of the flight position of the flight device 4 is the distance obtained by adding the error of the position information such as GPS and the position deviation amount in the flight performance of the flight device 4.

In the first moving step S102, the first position is a position predicted based on the position information of the photovoltaic power generation device 100 and the current time, and the actual state of the photovoltaic power generation device 100 (presence or absence of tracking deviation, etc.). ) Will not be known until the flight device 4 arrives and the image actually captured by the flight device 4 is confirmed. In the present embodiment, the array is set to a position separated from the array 10 by the first distance L11 in consideration of the maximum deviation amount L12 of the array 10 and the maximum deviation amount L13 of the flight position of the flight device 4. The flight device 4 can be brought closer to the array 10 while avoiding an unexpected collision with the 10.

Next, the calculation step S103 for calculating the posture information regarding the posture of the array 10 is executed based on the image obtained by aerial photography of the array 10 by the imaging unit 43 from the first position. When the calculation step S103 is started, first, the first image Im1 is acquired by taking an aerial image of the array 10 from the first position by the imaging unit 43 (first image acquisition step). Next, the calculation unit 611 generates a model image Md1 by performing image processing on the first image Im1 (model image generation step). Finally, the calculation unit 611 calculates the posture information based on the coordinates extracted from the model image Md1 (posture information calculation step). As a result, the calculation step S103 is completed.

FIG. 11 is an explanatory diagram showing an example of the first image Im1 and the model image Md1. In the first image Im1, four first marks 15 provided on the array 10 are shown. Further, the first image Im1 shows the second mark 16 provided on the drive unit 23. In the first image acquisition step, the first image Im1 captured by the imaging unit 43 is transmitted to the management device 6.

In the model image generation step, the calculation unit 611 performs image processing (for example, the shape of the mark) on the first image Im1 based on the information regarding the first mark 15 and the second mark 16 stored in the storage unit 64 (for example, the shape of the mark). For example, by performing pattern matching) and generating the model image Md1, four first marks 15 and second marks 16 are extracted from the first image Im1. It should be noted that the generation of the model image Md1 is not essential, and the first mark 15 and the second mark 16 may be directly extracted from the first image Im1.

In the posture information calculation step, first, the calculation unit 611 acquires the coordinates of the four first mark 15 and the second mark 16 (for example, the coordinates of the center of the mark) from the model image Md1. Here, since the first image Im1 is an image acquired by the two-dimensional image sensor, the coordinates of the four first mark 15 and the second mark 16 are two-dimensional coordinates, respectively. For example, the coordinates of the second mark 16 are (x, y). Next, the two-dimensional coordinates are based on the actual spatial coordinates (Xa, Ya, Za) provided with the second mark 16, information on the size of the array 10, and the line-of-sight direction D1 of the imaging unit 43. Then, it is converted into spatial coordinates (three-dimensional coordinates). As a result, the spatial coordinates of the four first marks 15 are acquired.

As described above, the actual spatial coordinates on which the second mark 16 is provided, the information on the size of the array 10, and the line-of-sight direction D1 of the imaging unit 43 are stored in the storage unit 64 in advance and are known. Is the value of. The information regarding the size of the array 10 is, for example, the distance between the first mark 15 and the second mark 16.

Next, the calculation unit 611 calculates the spatial plane to which the array 10 belongs by using the obtained spatial coordinates. Here, if the spatial coordinates of three or more points are known, the spatial plane can be calculated. In the present embodiment, the spatial plane is calculated using the spatial coordinates of the four first marks 15 and the second marks 16 (that is, the spatial coordinates of five points). The space plane is obtained, for example, by the following equation (1).
AX + BY + CZ + D = 0 ... (1)

Here, A, B, C and D are constants, and X, Y and Z are arbitrary coordinates of the space plane to which the array 10 belongs. Then, the calculation unit 611 outputs the constants A, B, C, and D as plane information regarding the plane to which the array 10 belongs, and stores the constants A, B, C, and D in the storage unit 64.

In the present embodiment, since the spatial plane is calculated based on the spatial coordinates of 5 points, which is more than 3 points, the error of the calculated spatial plane can be further reduced. Further, by arranging the known (that is, stored in the storage unit 64) first mark 15 and second mark 16 on the light receiving surface of the array 10, regardless of the imaging conditions of the first image Im1, the first mark 15 and the second mark 16 are arranged. The spatial coordinates on the light receiving surface of the array 10 can be extracted more accurately. This makes it possible to more accurately calculate the spatial plane to which the array 10 belongs.

Further, the calculation unit 611 calculates the normal vector of the plane to which the array 10 belongs based on the equation (1), and stores the normal vector in the storage unit 64 as normal information related to the normal of the array 10. Here, the normal vector has a direction parallel to the optical axis Ax of the array 10.

In the above, the calculation of the posture information when there is no deviation in the tracking of the array 10 has been described, but the attitude information can be calculated in the same manner even when there is a deviation in the tracking of the array 10.

FIG. 12 is an explanatory diagram showing an example of the first image Im2 and the model image Md2 when the tracking of the array 10 is deviated. In this case, the line-of-sight direction D1 of the imaging unit 43 is oriented in a direction non-parallel to the optical axis Ax of the array 10, and the array 10 has a shape different from the rectangular shape in the first image Im2 (in the case of this embodiment, the table). Shape). Even in this case, the plane information is the same as described above based on the coordinates of the four first marks 15 extracted by the model image Md2 generated from the first image Im2 and the coordinates of the second mark 16. And normal information can be obtained.

FIG. 13 is an explanatory diagram showing an example of the first image Im3 when there is no deviation in the tracking of the array 10 but there is a deviation in the flight position of the flight device 4. In this case, the line-of-sight direction D1 of the imaging unit 43 is oriented in a direction parallel to the optical axis Ax of the array 10, and the array 10 appears in a rectangular shape in the first image Im3. However, since the flight position of the flight device 4 deviates from the original first position, the array 10 looks different from the first image Im1 in the first image Im3.

In the example of FIG. 13, the first image Im3 is shown when the flight position of the flight device 4 is higher than the original first position and is deviated in the right-hand direction (direction of the first mark 15c, 15d side) of the array 10. ing. Therefore, the array 10 captured in the first image Im3 is smaller than the array 10 captured in the first image Im1, and is captured in a state shifted to the left from the center of the image. Even in this case, the plane information and the normal information can be acquired in the same manner as described above based on the coordinates of the four first marks 15 and the coordinates of the second mark 16 from the first image Im3. .. That is, even if the array 10 has a tracking deviation or the flight position of the flight device 4 has a deviation, the attitude information regarding the attitude of the array 10 can be calculated according to the inspection method according to the present embodiment.

Refer to FIG. Next, a determination step S104 is performed to determine whether or not there is a large deviation in the tracking of the array 10 based on the attitude information obtained in the calculation step S103. When the determination step S104 is started, first, the calculation unit 611 determines that there is no tracking deviation based on the current time and the actual spatial coordinates (Xa, Ya, Za) in which the second mark 16 is provided. The reference posture information regarding the posture of the array 10 is calculated.

If there is no tracking deviation in the array 10, the normal vector of the array 10 faces the direction of the sun. The direction of the sun with respect to the array 10 is calculated from the current time and the actual spatial coordinates provided with the second mark 16, and by setting the direction of the sun as the direction of the normal vector, the tracking of the array 10 is deviated. The reference plane to which the array 10 belongs can be calculated in the absence of. Then, the calculation unit 611 stores the reference plane information regarding the reference plane in the storage unit 64. The reference plane information is the reference attitude information according to the present embodiment.

Next, the calculation unit 611 compares the posture information calculated in the calculation step S103 with the reference posture information. For example, the difference between the plane information included in the attitude information and the reference plane information included in the reference attitude information is calculated. Then, when the difference is larger than the predetermined threshold value, it is determined that there is a deviation in the tracking of the array 10, and when the difference is equal to or less than the predetermined threshold value, there is no deviation in the tracking of the array 10. Is determined. As described above, the calculation unit 611 calculates the deviation information indicating whether or not there is a deviation in the tracking of the array 10, outputs the deviation information, and stores the deviation information in the storage unit 64.

When the calculation unit 611 outputs deviation information indicating that there is a deviation in the tracking of the array 10 (YES flow in FIG. 9), the control unit 61 issues an operation command to perform the notification step S107 described later. With such a configuration, a collision between the array 10 and the flight device 4 can be more reliably avoided. When the calculation unit 611 outputs deviation information indicating that there is no deviation in the tracking of the array 10 (NO flow in FIG. 9), the control unit 61 issues an operation command to perform the second movement step S105 described later. ..

Next, based on the attitude information obtained in the calculation step S103, the second moving step S105 that brings the flight device 4 closer to the array 10 than the first position is executed. In the present embodiment, the second moving step S105 is executed only when the calculation unit 611 outputs deviation information indicating that there is no deviation in the tracking of the array 10 in the determination step S104.

When the second moving step S105 is started, the calculation unit 611 is provided with the plane information obtained by the calculation step S103 and the position information of the photovoltaic power generation device 100 (specifically, the second mark 16). Based on the spatial coordinate information), a position separated from the array 10 by a second distance L14 on the optical axis Ax of the array 10 is calculated as an inspection position. Then, the control unit 61 outputs the information regarding the inspection position to the control unit 45 via the communication unit 65 and the communication unit 47.

The control unit 45 performs a second flight control for flying the flight device 4 to the inspection position based on the position information of the flight device 4 by the position information acquisition unit 44 and the information regarding the inspection position. In the second flight control, the control unit 45 performs a third flight control that brings the flight device 4 closer to the array 10 along the normal line of the array 10 based on the normal information. By bringing the flight device 4 closer along the normal of the array 10 in this way, the flight device can be brought closer to the array while more reliably avoiding an unexpected collision with the array.

Further, the control unit 45 directs the line-of-sight direction D1 of the image pickup unit 43 to the direction parallel to the normal vector included in the attitude information (that is, the direction of the actually measured optical axis Ax) by the arm unit 422. As a result, the second moving step S105 is completed.

FIG. 14 is an explanatory diagram schematically showing the positional relationship between the flight device 4 and the photovoltaic power generation device 100 at the end of the second moving step S105. In this embodiment, the inspection position is located between the sun and the array 10. The second distance L14 is shorter than the first distance L11 (see FIG. 10). That is, the inspection position is closer to the array 10 than the first position. More preferably, the second distance L14 is a distance shorter than the maximum deviation amount L12 of the array 10. Due to the second flight control of the control unit 45, the flight device 4 is closer to the array 10 than the first position and is positioned at the inspection position.

In the inspection step S106 described later, the inspection is performed based on the image obtained by aerial photography of the array 10 from the inspection position by the imaging unit 43. Therefore, the second distance L14, which is the distance between the array 10 and the inspection position, is determined according to the resolution of the image required for the inspection. That is, when the array 10 is inspected in more detail, the required image resolution is increased, so that the second distance L14 is shortened.

After the second moving step S105, the inspection step S106 for inspecting the photovoltaic power generation device 100 by the flight device 4 is executed from a position closer to the array 10 than the first position. When the inspection step S106 is started, the flight apparatus 4 empties the array 10 a plurality of times while scanning the array 10 along a predetermined path P1 while maintaining the second distance L14 from the array 10. Take a picture. FIG. 15 is an explanatory diagram showing how the flight device 4 scans the array 10 along the path P1. FIG. 16 is an explanatory diagram showing how the flight device 4 inspects the array 10 at the position P2 on the upstream side of the path P1 shown in FIG. FIG. 17 is an explanatory diagram showing how the flight device 4 inspects the array 10 at the position P3 on the downstream side of the path P1 shown in FIG.

While the flight device 4 scans the array 10 along the path P1, the array 10 is tracking the sun due to the tracking operation of the tracking device 2. Therefore, the posture of the array 10 changes from moment to moment, and the position separated from the array 10 by the second distance L14 also changes from moment to moment. Therefore, the calculation unit 611 calculates the current posture information regarding the posture of the array 10 at the current time based on the posture information calculated in the calculation step S103 and the current time. The calculation unit 611 may calculate the current posture information at intervals of 1 minute to 5 minutes, or may calculate the current posture information at intervals of 1 second.

Specifically, the current plane information is acquired by calculating the amount of movement of the sun between the time when the plane information was calculated and the current time, and changing the plane information based on the movement amount. Further, the calculation unit 611 calculates the normal vector of the plane to which the array 10 belongs at the current time based on the current plane information. Then, the normal vector is stored in the storage unit 64 as the current normal information regarding the current normal of the array 10. Here, the normal vector is in a direction parallel to the optical axis Ax of the current time of the array 10. The current attitude information includes the current plane information and the current normal information.

The control unit 45 performs the fourth flight control to fly the flight device 4 in the direction along the array 10 based on the current attitude information output from the calculation unit 611. As a result, even when the attitude of the array 10 changes, the flight device 4 can fly while maintaining the distance from the array 10 at the second distance L14. Then, the image pickup unit 43 takes an aerial photograph of the array 10 and acquires a plurality of second images while the flight device 4 flies in the direction along the array 10. Further, by irradiating the laser from the irradiation unit 423 and incident the laser reflected from the array 10 on the image pickup unit 43, shape information regarding the surface shape of the array 10 is acquired.

The plurality of second images and shape information acquired by the imaging unit 43 are transmitted from the flight device 4 to the management device 6. Then, the inspection unit 612 included in the control unit 61 of the management device 6 inspects the abnormality of the array 10 based on the plurality of second images and the shape information. The inspection unit 612 inspects the abnormality of the array 10 by comparing the reference image with the second image, for example. Examples of the abnormality of the array 10 include damage, dirt, and bending of the array 10, tracking deviation in units of 1M of modules, and the like.

Specifically, as shown in FIG. 16, the flight device 4 takes an aerial image of the array 10 by the imaging unit 43 at a position P2 separated from the array 10 by a second distance L14, and acquires a second image. Further, by irradiating the laser light B1 from the irradiation unit 423 and incident the laser light B1 reflected from the array 10 on the imaging unit 43, the distance from the irradiation unit 423 to the array 10 is measured, and the surface shape of the array 10 is measured. Get information about.

Since the position P2 is located on the upstream side of the path P1, it is a position where the flight device 4 passes relatively quickly after approaching the array 10 by the second moving step S105. Therefore, the time from the time when the first image Im1 is acquired until the flight device 4 reaches the position P2 is short, and the above-mentioned current plane information and the plane information acquired by the calculation step S103 are almost the same information. Therefore, when the time from the acquisition of the first image Im1 to the inspection is short, the flight device 4 may be flown based on the plane information acquired in the calculation step S103 instead of the current plane information.

Refer to FIG. FIG. 17 shows how the array 10 is tilted in the elevation angle direction by an angle An1 while the flight device 4 flies from the position P2 to the position P3. In FIG. 17, the position of the array 10 when the flight device 4 reaches the position P2 is shown by a chain double-dashed line, and the position of the array 10 when the flight device 4 reaches the position P3 is shown by a solid line.

As shown in FIG. 17, the flight device 4 flies based on the current plane information output from the calculation unit 611, so that even if the attitude of the array 10 changes, the second distance to and from the array 10 is changed. It is positioned at the position where L14 is maintained. Further, the flight device 4 rotates the arm unit 422 based on the current normal information output from the calculation unit 611, and makes the line-of-sight direction D2 of the image pickup unit 43 parallel to the optical axis Ax of the array 10.

As a result, even if the posture of the array 10 changes from moment to moment, the imaging unit 43 can always take aerial images from a direction parallel to the optical axis Ax of the array 10. Since the array 10 is captured at the same angle on the plurality of second images acquired by the imaging unit 43, it becomes easier to compare with other images (for example, the second images acquired in the past inspection) at the time of inspection. The accuracy of inspection can be improved. Further, even if the posture of the array 10 changes from moment to moment, the angle of incidence and reflection of the laser light B2 emitted from the irradiation unit 423 on the array 10 is the same as that of the laser light B1. Therefore, the surface shape of the array 10 can be acquired more accurately.

Refer to FIG. When the inspection unit 612 determines in the inspection step S106 that there is an abnormality in the array 10, the notification step S107 is executed. When the notification step S107 is started, the display unit 63 displays that there is an abnormality in the array 10.

Subsequently, the recording step S108 is executed. When the recording step S108 is started, a plurality of second images, shape information, and inspection information regarding the inspection results by the inspection unit 612 are stored in the storage unit 64.

Finally, the landing process S109 is executed. When the landing step S109 is executed, the flight device 4 rises from the inspection position to a predetermined height, then returns to the position (X1, Y1, Z1) shown in FIG. 1 and lands. This completes the inspection method according to this embodiment.

As described above, the inspection system 1 according to the present embodiment flies the flight device 4 to the first position based on the GPS signal and the current time. After that, the first image Im1 is acquired by taking an aerial image of the array 10 from the first position. Then, the attitude information regarding the attitude of the array 10 is calculated by the calculation unit 611 based on the first image Im1, and the flight device 4 is brought closer to the array 10 than the first position based on the attitude information.

Since the flight device 4 is brought closer based on the attitude information, even if the attitude of the array 10 changes with the movement of the sun, the array from a closer position while avoiding a collision between the array 10 and the flight device 4. 10 can be inspected. The flight device 4 flies when the control unit 45 issues an operation command based on various information. That is, so-called automatic flight is performed. Therefore, the administrator of the photovoltaic power generation device 100 does not need to control the flight of the flight device 4 by a remote controller or the like, and the administrator only gives an instruction to start the inspection, and a plurality of second images for the inspection are used. Can be obtained. Therefore, it is possible to reduce the management burden on the maintenance and inspection of the photovoltaic power generation device 100.

<< Modification example >>
Although the embodiments of the present disclosure have been described above, the present disclosure can be modified in various ways other than the above-described embodiments. Hereinafter, a modified example according to the embodiment of the present disclosure will be described. In the following modification, the same components as those in the embodiment are designated by the same reference numerals and the description thereof will be omitted.

<< First modification >>
FIG. 18 is a block diagram schematically showing a functional configuration of the inspection system 1a according to the first modification. This modification is different from the above embodiment in that the control unit 45a of the flight device 4a has a calculation unit 451 and an inspection unit 452, and other points are common. The calculation unit 451 has the same function as the calculation unit 611 according to the above embodiment. The inspection unit 452 has the same function as the inspection unit 612 according to the above embodiment. That is, in this modification, the flight device 4a performs calculations associated with calculation and inspection of attitude information. As a result, the amount of information transmitted and received between the flight device 4a and the management device 6a can be reduced.

<< Second variant >>
FIG. 19 is an explanatory diagram showing a flight device 4 and a photovoltaic power generation device 101 according to the inspection system 1b according to the second modification. FIG. 20 is a block diagram schematically showing the functional configuration of the inspection system 1b according to the second modification. This modification is different from the above embodiment in that the photovoltaic power generation device 101 has a communication unit 71 and a storage unit 72, and other points are common. The communication unit 71 transmits / receives information to / from the communication unit 47 and the communication unit 65. That is, the communication unit 71 has a function of relaying the transmission / reception of information between the communication unit 47 and the communication unit 65. The storage unit 72 stores the information received by the communication unit 71.

The flight device 4 operates each unit by supplying electric power from a battery (not shown) to the drive unit 42, the image pickup unit 43, and the communication unit 47. In order to make the flight device 4 fly for a longer time, it is necessary to take measures such as reducing the power consumption in the communication unit 47. In this modification, the communication unit 47 of the flight device 4 and the communication unit 65 of the management device 6 transmit and receive information via the communication unit 71 of the photovoltaic power generation device 101. As a result, the communication unit 47 may directly communicate with the communication unit 71 located closer than the communication unit 65, so that the strength of the signal transmitted for communication can be further weakened. Therefore, the power consumption in the communication unit 47 can be reduced, and the flight device 4 can be flown for a longer time. The information transmitted from the communication unit 65 may be directly received by the communication unit 47 or may be received by the communication unit 47 after passing through the communication unit 71, as in the above embodiment.

<< Third variant >>
FIG. 21 is a perspective view showing the configuration of the module 1M having the shielding plate 140 according to the third modification. This modification is different from the above embodiment in that a plurality of first marks 150 are provided on the surface of the shielding plate 140 on the light collecting portion 12 side, and other points are common. When a plurality of openings 140a are formed in the shielding plate 140 and the incident angle of sunlight with respect to the module 1M is 0 degrees, the light collected by the Fresnel lens 12f passes through the openings 140a and is incident on the light receiving unit 3. ..

In the inspection method according to this modification, the imaging unit 43 takes an aerial image of the first image Im1 including the plurality of first marks 150 and the second mark 16, and the first mark 150 and the second mark 150 acquired from the first image Im1 are taken aerial. The plane information of the array 10 is calculated based on the coordinates of the mark 16. The surface of the shielding plate 140 on the condensing portion 12 side does not block the sunlight condensing on the light receiving portion 3. Therefore, the first mark 150 is provided at a position that does not block the sunlight that is focused on the light receiving unit 3. Therefore, the plane information can be acquired more accurately while maintaining the power generation performance of the light receiving unit 3.

<< Fourth variant >>
FIG. 22 is an explanatory diagram showing a state of the first moving step S105 according to the fourth modified example. In this modification, regardless of the posture of the array 10, a position separated from the drive unit 23 in the vertical direction by a first distance L15 is set as the first position.

The first distance L15 is a distance (L15 = L12 + L13) obtained by adding the maximum deviation amount L12 of the array 10 and the maximum deviation amount L13 of the flight position of the flight device 4 as in the first distance L11 of the above embodiment. be. Further, at the first position, the arm portion 422 directs the line-of-sight direction D3 of the imaging unit 43 downward in the vertical direction. In the example of FIG. 22, the optical axis Ax of the array 10 faces the direction of the sun 9, and is inclined in the elevation angle direction by an angle An2 from the vertical direction (that is, the line-of-sight direction D3).

The array 10 changes its posture around the drive unit 23. Therefore, if the array 10 is aerial photographed from above the drive unit 23 in the vertical direction, the light receiving surface of the array 10 can be imaged on the first image Im except when the array 10 is along the vertical direction as shown in FIG. can. The array 10 is usually along the vertical direction before dawn and sunset. Since the above inspection is performed during the daytime, the light receiving surface of the array 10 can be imaged on the first image Im regardless of the posture of the array 10. Therefore, it is not necessary to predict the attitude of the array 10 when positioning the flight device 4 at the first position, and the processing load on the calculation unit 611 can be reduced.

<< Fifth variant >>
In the above embodiment, the shape and color of the second mark 16 are the same as those of the first mark 15. However, in the practice of the present disclosure, the present invention is not limited to this, and at least one of the shape and color of the second mark 16 may be different from that of the first mark 15. For example, when the first mark 15 is a red mark, the second mark 16 may be a black mark.

In the calculation step S103, the first is by associating the two-dimensional coordinates (x, y) of the second mark 16 reflected in the first image Im1 with the known spatial coordinates (Xa, Ya, Za) of the second mark 16. The two-dimensional coordinates of the plurality of first marks 15 appearing in the image Im1 are converted into spatial coordinates. By making at least one of the shape and color of the second mark 16 different from the first mark 15, the first mark and the second mark can be easily distinguished in the first image, so that the plane information can be more accurately defined. Can be obtained.

<< 6th variant >>
In the above embodiment, the plane information regarding the plane to which the array 10 belongs was calculated by using a plurality of first marks 15 and second marks 16 provided on the array 10. However, it is not essential that the array 10 is provided with the plurality of first marks 15 and that the drive unit 23 is provided with the second marks 16.

For example, even if characteristic parts of the array 10 such as the corners of the array 10 are stored in the storage unit 64 in advance and these characteristic parts are extracted from the first image Im1 as a plurality of first feature parts by pattern matching. good. Further, the shape of the drive unit 23 may be stored in the storage unit 64 and extracted from the first image Im1 as the second feature unit. Then, based on the coordinates of the plurality of first feature portions and the coordinates of the second feature portion in the first image Im1, the spatial coordinates of the second feature portion and the size of the array stored in advance in the storage unit 64. , Plane information about the plane to which the array 10 belongs may be acquired.

That is, a plurality of first feature portions may be extracted from the array 10 captured in the first image Im1, and the first feature portion may be the first mark 15 provided on the array 10 or the array. It may be a characteristic part of the array 10 itself, such as a corner of 10. Similarly, the second feature portion may be extracted from the immovable portion captured in the first image Im1, and the second feature portion may be the second mark 16 provided in the drive unit 23 or may be driven. It may be a characteristic part of the part 23 itself.

Further, when a plurality of first marks 15 are provided, they may be provided on a surface other than the light receiving surface of the array 10. For example, a plurality of ear-shaped portions may be further provided from the peripheral edge of the array 10, and the first mark 15 may be provided on each of the plurality of portions.

<< 7th variant >>
In the above embodiment, the array 10 is inspected based on a plurality of second images obtained by aerial photography of the array 10 by the imaging unit 43. However, the content of the inspection of the array 10 is not limited to this, and for example, the imaging unit 43 may be further provided with an infrared camera, and the infrared camera may be used to inspect the abnormal heat generation in the array 10. With this configuration, it is possible to detect defects in the array 10 that cannot be found by visual inspection.

<< Eighth variant >>
In the above embodiment, the array 10 is inspected by taking an aerial image of the array 10 by the imaging unit 43 along the path P1. However, for example, the tracking device 2 may be inspected by aerial photography of the tracking device 2, or the array 10 may be inspected by aerial photography of the array 10 from the back surface side of the array 10 (that is, the side that becomes the shadow of the sun). You may inspect the back side of the.

If the attitude information of the array 10 can be acquired by the calculation step S103, it is possible to take an aerial photograph of an arbitrary part of the photovoltaic power generation device 100 while avoiding a collision between the array 10 and the flight device 4. Therefore, in the inspection step S106, the photovoltaic power generation device 100 may be inspected by taking an aerial photograph of the photovoltaic power generation device 100 from an inspection position closer to the first position.

"others"
In the above embodiment, in the determination step S104, if there is a large deviation in the tracking of the array 10, the inspection step S106 is not performed. However, even if there is a large deviation in the tracking of the array 10, if the attitude information can be acquired, it is possible to approach the array 10 while avoiding a collision with the flight device 4. Therefore, the second moving step S105 and the inspection step S106 may be performed as they are after calculating the posture information without performing the determination step S104.

In the above embodiment, the GPS receiver is installed in the vicinity of the position where the second mark 16 is provided in the drive unit 23, and the coordinates (Xa) of the second mark 16 are based on the GPS signal received by the GPS receiver. , Ya, Za) may be acquired.

In the above embodiment, an example in which the tracking device 2 changes the posture of the array 10 from moment to moment has been described. However, the tracking device 2 may perform an intermittent operation of intermittently changing the posture of the array 10, for example, changing the posture of the array 10 only once per minute. In this case, the storage unit 64 stores information regarding the content of the intermittent operation by the tracking device 2 (for example, the tracking interval and the like), and the flight control of the flight device 4 is performed based on the information.

Further, in the above embodiment, when the array 10 has no tracking deviation, the optical axis Ax of the array 10 faces the direction of the sun. However, the tracking device 2 may perform an offset operation that shifts the optical axis Ax of the array 10 by a small amount from the direction of the sun in order to absorb an error in the construction of the array 10 (for example, bending). In this case, the storage unit 64 stores information (for example, an offset amount, etc.) regarding the content of the offset operation by the tracking device 2, and the flight control of the flight device 4 is performed based on the information.

<< Supplement >>
It should be noted that at least a part of the above-described embodiment and various modifications may be arbitrarily combined with each other. In addition, the embodiments disclosed this time should be considered to be exemplary in all respects and not restrictive. The scope of the present disclosure is indicated by the claims and is intended to include all modifications within the meaning and scope equivalent to the claims.

1, 1a, 1b Inspection system 10 Array 11 Housing 11b Bottom 111 Bottom plate 112 Frame 12 Condensing unit 12a (Condensing unit 12) Front surface 12b (Condensing unit 12) Back surface 12f Fresnel lens 13 Flexible printed wiring board 14 , 140 Shielding plate 14a, 140a Opening 15, 15a, 15b, 15c, 15d, 150 1st mark (1st feature part)
16 2nd mark (2nd feature part)
100, 100a, 100b, 101 Photovoltaic power generation device 1M Photovoltaic power generation module 1U Photovoltaic power generation unit 2 Tracking device 21 Strut 22 Foundation 23 Drive unit 24 Horizontal axis 25 Tracking mount 25a Reinforcing material 25b Rail 3 Light receiving part 30 Ball lens 31 Plate 31e Upper end Inner peripheral edge 32 Support 33 Package 34 Cell 35 Lead frame 36 Gold wire 37 Lead frame 38 Sealing part 4, 4a Flying device 41 Main body 42 Drive part 421 Propeller part 422 Arm part 423 Irradiation part 43 Imaging part 44 Position Information acquisition unit 45, 45a Control unit 451 Calculation unit 452 Inspection unit 46 Storage unit 47 Communication unit 6, 6a Management device 61 Control unit 611 Calculation unit 612 Inspection unit 62 Input unit 63 Display unit 64 Storage unit 641 Program 65 Communication unit 66 Reading Part 661 Recording medium 71 Communication part 72 Storage part 9 Sun D1, D2, D3 Line-of-sight direction L11 1st distance L12 Maximum deviation of array 10 L13 Maximum deviation of flight position of flight device 4 L14 2nd distance L15 1st distance Im1 , Im2, Im3 1st image Md1, Md2 Model image P1 Path P2 Position P3 Position B1 Laser light B2 Laser light An1 Angle An2 Angle Ax Optical axis

Claims (13)

1. An inspection system that inspects a photovoltaic power generation device having an array and a tracking device that changes the attitude of the array as the sun moves.
   Flying equipment and
   Imaging unit and
   Calculation part and
   Control unit and
   With
   The flight device is capable of flying and stationary in the air.
   The image pickup unit is provided in the flight device, and the array is aerial photographed from a first position to acquire a first image.
   The calculation unit calculates posture information regarding the posture of the array based on the first image.
   The control unit
   The first flight control for flying the flight device to the first position, and
   A second flight control that brings the flight device closer to the array than the first position based on the attitude information.
   Inspection system to do.
2. The attitude information includes plane information about the plane to which the array belongs.
   The second flight control includes a control for positioning the flight device between the first position and the plane based on the plane information.
   The inspection system according to claim 1.
3. The calculation unit
   A plurality of first feature portions are extracted from the array shown in the first image, and a plurality of first feature portions are extracted.
   The second feature portion is extracted from the immovable portion shown in the first image, and the second feature portion is extracted.
   The plane information is calculated based on the coordinates of the plurality of first feature portions, the coordinates of the second feature portion, and the size of the array.
   The inspection system according to claim 2.
4. The immovable portion is a portion of the tracking device located on the same plane as the array.
   The inspection system according to claim 3.
5. The first feature portion is a first mark provided on the array.
   The inspection system according to claim 3 or 4.
6. The array has multiple modules
   The module is provided between a light receiving unit including a power generating element, a condensing unit that collects sunlight on the light receiving unit, and the light receiving unit and the condensing unit, and does not condense sunlight on the light receiving unit. Has a shielding part, which shields the light
   The first mark is provided on the surface of the shielding portion on the light collecting portion side.
   The inspection system according to claim 5.
7. The second feature portion is a second mark provided on the immovable portion.
   At least one of the shape and color of the second mark is different from the first mark.
   The inspection system according to claim 5 or 6.
8. The first position is located above the portion of the array that is the center of the change in posture in the vertical direction.
   The inspection system according to any one of claims 1 to 7.
9. Based on the attitude information, the calculation unit calculates deviation information indicating whether or not there is a deviation in the tracking of the array.
   When the deviation information indicating that there is no deviation is output from the calculation unit, the control unit performs the second flight control based on the attitude information.
   The inspection system according to any one of claims 1 to 8.
10. The attitude information includes normal information about the normal of the array.
    The second flight control includes a third flight control that brings the flight device closer to the array along the normal based on the normal information.
    The inspection system according to any one of claims 1 to 9.
11. The calculation unit calculates the current posture information regarding the posture of the array at the current time based on the posture information and the current time.
    After the second flight control, the control unit performs a fourth flight control to fly the flight device in a direction along the array based on the current attitude information.
    The imaging unit acquires a plurality of second images by aerial photography of the photovoltaic power generation device while the control unit performs the fourth flight control.
    The inspection system according to any one of claims 1 to 10.
12. Further, an inspection unit for inspecting whether or not there is an abnormality in the photovoltaic power generation device based on the plurality of second images is provided.
    The inspection system according to claim 11.
13. An inspection method that inspects photovoltaic power generation equipment that has an array that tracks the sun.
    The first moving step of flying the flight device having the image pickup unit to the first position, and
    A calculation step of calculating posture information regarding the posture of the array based on an image obtained by aerial photography of the array by the imaging unit from the first position.
    A second moving step of bringing the flight device closer to the array than the first position based on the attitude information.
    After the second moving step, an inspection step of inspecting the photovoltaic power generation device by the flight device from a position closer to the array than the first position,
    The inspection method.
    

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