Facility inspection device and facility inspection method

Abstract

The objective of the present disclosure is to use an unmanned aerial vehicle to capture an inspection video that allows an inspection of a wind-powered electricity generation facility to be carried out with a high degree of accuracy. A facility inspection device (101) comprises a position acquiring unit (11) that acquires position information of an unmanned aerial vehicle (201), a condition acquiring unit (12) that acquires imaging conditions necessary for inspection imaging of a wind-powered electricity generation facility (401), an inspecting unit (13) that, on the basis of the imaging conditions, determines an inspection state, which is the state of the wind-powered electricity generation facility (401) to be adopted during the inspection imaging, and determines an inspection route, which is the flight route of the unmanned aerial vehicle (201) during the inspection imaging, a facility control unit (15) that controls the wind-powered electricity generation facility (401) to adopt the inspection state, and a flight control unit (14) that causes the unmanned aerial vehicle (201) to fly along the inspection route on the basis of the position information in a state in which the wind-powered electricity generation facility (401) has been controlled to adopt the inspection state, wherein the inspecting unit (13) causes an imaging device (24) to image the wind-powered electricity generation facility (401) while the unmanned aircraft (201) is flying along the inspection route.

Description

Equipment inspection device and equipment inspection method

[0001] The present disclosure relates to inspection of wind power generation equipment.

[0002] Conventionally, inspectors have had to travel to the installation site to inspect wind power generation facilities, but because wind power generation facilities are usually installed in coastal or offshore locations far from urban areas, there is a problem of the cost and time required for inspectors to travel there.

[0003] To address this issue, Patent Document 1 introduces a system for inspecting wind power generation facilities using an unmanned aerial vehicle equipped with a camera. This system photographs the wind power generation facility using the unmanned aerial vehicle while rotating and stopping the blades of the wind power generation facility, and inspects the wind power generation facility using the photographed images.

[0004] Special Publication No. 2020-512629

[0005] However, the system of Patent Document 1 takes photographs without any consideration of how to control each part of the wind power generation equipment according to the conditions required for photographing the wind power generation equipment, such as the inspection content of the wind power generation equipment or environmental conditions, so there is a problem that optimal images may not be obtained, which could reduce the accuracy of the inspection and analysis of the wind power generation equipment.

[0006] The present disclosure has been made to solve the above-mentioned problems, and aims to use an unmanned aerial vehicle to capture inspection footage that enables highly accurate inspection of wind power generation equipment.

[0007] The equipment inspection device disclosed herein comprises a position acquisition unit that acquires position information of an unmanned aerial vehicle that performs inspection photography while flying and photographing inspection points of wind power generation equipment using an onboard photographing device; a condition acquisition unit that acquires the photographing conditions necessary for inspecting and photographing the wind power generation equipment; an inspection unit that determines the inspection state, which is the state of the wind power generation equipment that should be taken during inspection photography based on the photographing conditions, and determines the inspection route, which is the flight route of the unmanned aerial vehicle during inspection photography; an equipment control unit that controls the wind power generation equipment to be in the inspection state; and a flight control unit that causes the unmanned aerial vehicle to fly the inspection route based on the position information while the wind power generation equipment is controlled to the inspection state, and the inspection unit causes the photographing device to photograph the wind power generation equipment while the unmanned aerial vehicle is flying along the inspection route.

[0008] The equipment inspection device of the present disclosure controls the wind power generation equipment to be in an inspection state based on the shooting conditions, and then flies the unmanned aerial vehicle along the inspection route, making it possible to capture inspection footage that is optimal for inspecting the wind power generation equipment with high precision. Objects, features, aspects, and advantages of the present disclosure will become more apparent from the following detailed description and the accompanying drawings.

[0009] 1 is a block diagram showing the configuration of an equipment inspection system according to a first embodiment. FIG. 2 is a schematic diagram of the structure of a wind power generation facility. FIG. 3 is a flowchart showing the operation of an equipment inspection device according to the first embodiment. FIG. 4 is a diagram showing a list of inspection items according to the first embodiment. FIG. 5 is a diagram showing shadows cast on blades of a wind power generation facility. FIG. 6 is a diagram showing the position of an unmanned aerial vehicle before the start of an overall inspection. FIG. 7 is a diagram showing the position of an unmanned aerial vehicle at the start of an overall inspection. FIG. 8 is a diagram showing an example of an inspection route for an overall inspection. FIG. 9 is a diagram showing an example of an inspection route for a nacelle inspection. FIG. 10 is a diagram showing an example of an inspection route for a nacelle inspection. FIG. 11 is a diagram showing an example of an inspection route for a blade inspection. FIG. 12 is a diagram showing an example of an inspection route for a blade inspection. FIG. 13 is a diagram showing an example of an inspection route for a blade inspection. FIG. 14 is a diagram showing an example of an inspection route for a blade inspection taking into account wind direction. FIG. 15 is a diagram showing an example of an inspection route for a blade inspection taking into account wind direction and the direction of the sun. FIG. 16 is a diagram showing an example of an inspection route for a blade inspection taking into account wind direction and the direction of the sun. 1 is a diagram showing a list of inspection items according to embodiment 2. FIG. 2 is a diagram showing an example of an inspection route for blade inspection by close-range flight. FIG. 3 is a diagram showing an example of an inspection route for blade inspection by close-range flight. FIG. 4 is a block diagram showing the configuration of an equipment inspection system according to a first modified example of embodiment 2. FIG. 5 is a diagram showing the yaw angle, roll angle, and pitch angle of an offshore wind power generation facility. FIG. 6 is a diagram showing the yaw angle of an offshore wind power generation facility. FIG. 7 is a diagram showing the roll angle of an offshore wind power generation facility. FIG. 8 is a diagram showing the pitch angle of an offshore wind power generation facility. FIG. 9 is a diagram showing the hardware configuration of an equipment inspection device. FIG. 10 is a diagram showing the hardware configuration of an equipment inspection device.

[0010] <A. Embodiment 1> <A-1. Configuration> Fig. 1 is a diagram showing the configuration of an equipment inspection system 1001 according to embodiment 1. The equipment inspection system 1001 is configured to include an unmanned aerial vehicle 201 such as a drone, a command center 301 provided on the ground, and a wind power generation facility 401 to be inspected.

[0011] The unmanned aerial vehicle 201 is configured with a Global Navigation Satellite System (GNSS) 21, a flight device 22, a communication device 23, an imaging device 24, and an equipment inspection device 101. The GNSS 21 performs satellite positioning of the position information of the unmanned aerial vehicle 201. The flight device 22 is a driving device that causes the unmanned aerial vehicle 201 to fly, and corresponds to a propeller and a motor. The communication device 23 communicates with the command center 301 and the wind power generation facility 401. The imaging device 24 is a camera that inspects and photographs the wind power generation facility.

[0012] The command center 301 is configured to include a communication unit 31, an inspection planning unit 32, a data collection unit 33, and a video analysis unit 34. The communication unit 31 communicates with the communication device 23 of the unmanned aerial vehicle 201 and the communication unit 41 of the wind power generation facility 401. The inspection planning unit 32 plans the inspection of the wind power generation facility 401 to be inspected, and provides the inspection details and information about the wind power generation facility 401 to the facility inspection device 101 via the communication unit 31. The data collection unit 33 collects inspection video captured by the unmanned aerial vehicle 201 via the communication unit 31. The video analysis unit 34 analyzes the inspection collected by the data collection unit 33 and obtains information about whether the wind power generation facility 401 is damaged and the state of the damage.

[0013] FIG. 2 shows an outline of the structure of a wind power generation facility 401. The wind power generation facility 401 is a device that generates electricity by receiving wind and is configured with a communication unit 41, a control unit 42, an attitude control unit 43, multiple blades 44, a nacelle 45, a tower 46, and a hub 47. Although FIG. 2 shows three blades 44A, 44B, and 44C as the multiple blades 44, the number of blades 44 is not limited to this. The blades 44 rotate when receiving wind. A hub 47 connects the three blades 44. The configuration consisting of the multiple blades 44 and the hub 47 is also referred to as a rotor. The nacelle 45 transmits the rotation of the rotor to an internal generator to generate wind power. The horizontal rotation angle φ of the nacelle 45 is referred to as yaw, and this can be changed depending on the wind direction. The tower 46 supports the nacelle 45.

[0014] The communication unit 41 communicates with the command center 301 and the unmanned aerial vehicle 201. The control unit 42 controls the entire wind power generation facility 401. The attitude control unit 43 controls the drive, stop, rotation angle θ, pitch angle α, and yaw φ of the nacelle 45 of the multiple blades 44. The stop of the multiple blades 44 controlled by the attitude control unit 43 also includes setting the rotation angle at the time of stop. FIG. 2 shows the rotation angle θa of the blade 44A when the upward direction is set to 0 degrees. The pitch angle α of the blade 44 is the angle of the blade 44 relative to the wind direction. The rotation speed of the blade 44 is adjusted by the pitch angle α. The yaw φ of the nacelle 45 is determined, for example, with the angle at which the hub 47 faces north being set to 0 degrees. In FIG. 2, the height of the tower 46 is 100 m, the length of the blade 44 is 50 m, the length of the nacelle 45 is 10 m, and the length from the center of rotation of the nacelle 45 to the hub 47 is 4 m.

[0015] The equipment inspection device 101 is configured with a position acquisition unit 11, a condition acquisition unit 12, an inspection unit 13, a flight control unit 14, and an equipment control unit 15.

[0016] The position acquisition unit 11 acquires position information of the unmanned aerial vehicle 201 from the GNSS 21. The condition acquisition unit 12 acquires imaging conditions for the wind power generation facility 401. The imaging conditions are conditions necessary for the imaging device 24 to properly image the wind power generation facility 401. The imaging conditions include the inspection location, the inspection content, and the direction of the sun.

[0017] The inspection unit 13 acquires inspection details from the command center 301 via the communication device 23, and determines the route that the unmanned aerial vehicle 201 will fly during inspection (hereinafter referred to as the "inspection route") and the state, including the operating state or attitude, of the wind power generation facility 401 during inspection according to the acquired inspection details. Furthermore, the inspection unit 13 controls the flight control unit 14, the facility control unit 15, and the imaging device 24 according to these decisions, thereby causing the wind power generation facility 401 to assume an optimal state during inspection, flying the unmanned aerial vehicle 201 along the inspection route, and causing the imaging device 24 to photograph the wind power generation facility 401. The inspection unit 13 transmits inspection video captured by the imaging device 24 to the command center 301 via the communication device 23.

[0018] The flight control unit 14 controls the flight device 22 to cause the unmanned aerial vehicle 201 to fly and hover along a specific route. The flight control unit 14 also causes the unmanned aerial vehicle 201 to fly along the inspection route determined by the inspection unit 13. The equipment control unit 15 controls the wind power generation equipment 401 in accordance with the state of the wind power generation equipment 401 determined by the inspection unit 13.

[0019] <A-2. Operation> Figure 3 is a flowchart showing the operation of the equipment inspection device 101. Below, the operation of the equipment inspection device 101 will be explained in accordance with the flow in Figure 3. In the following explanation, for simplicity, it is assumed that the nacelle 45 before control by the equipment control unit 15 faces north (nacelle yaw φ = 0°) and that the sun is at its zenith and located due south.

[0020] First, an inspection plan for the wind power generation facility 401 is created in the inspection planning unit 32 of the command center 301, and an inspection photography instruction in accordance with the inspection plan is sent to the inspection unit 13 via the communication unit 31 and the communication device 23. Thus, in step S101, the inspection unit 13 receives the inspection photography instruction. This inspection photography instruction includes the ID, location information, and inspection items of the wind power generation facility 401 to be inspected.

[0021] Next, in step S102, the inspection unit 13 creates a flight plan from the current position of the unmanned aerial vehicle 201 to the wind power generation facility 401, and causes the flight control unit 14 to fly the unmanned aerial vehicle 201 in accordance with the flight plan. Based on the position information of the unmanned aerial vehicle 201, the flight control unit 14 causes the unmanned aerial vehicle 201 to fly to a specific position near the wind power generation facility 401, for example, to a position 100 m above the nacelle 45. This state is shown in Figure 6. In order to measure the specific position near the wind power generation facility 401, the flight control unit 14 may use, in addition to the GNSS 21, images captured by the imaging device 24 or other distance sensors mounted on the unmanned aerial vehicle 201.

[0022] Thereafter, in step S103, the condition acquisition unit 12 acquires the photographing conditions. Here, the photographing conditions may be inspection details included in the inspection photographing instruction received by the inspection unit 13. The photographing conditions may also include the solar azimuth angle at the wind power generation facility 401. In this case, the photographing device 24 photographs the sun while the unmanned aerial vehicle 201 is parked at a specific position near the wind power generation facility 401. The condition acquisition unit 12 acquires video photographed by the photographing device 24 and acquires the solar azimuth angle from the orientation at the time of photographing by the photographing device 24. Note that the condition acquisition unit 12 may also acquire the solar azimuth angle by other methods. For example, the condition acquisition unit 12 may calculate the solar azimuth angle at the location of the wind power generation facility 401 from the current date and time and location information of the wind power generation facility 401.

[0023] The inspection photography instruction received by the inspection unit 13 includes an inspection number corresponding to the inspection item to be carried out. FIG. 4 shows a list of inspection items. For each inspection item with inspection number n=1-8, the inspection route for the unmanned aerial vehicle 201 and the inspection state that the wind power generation facility 401 should be in during the inspection are defined. In the following explanation, it is assumed that the inspection photography instruction in step S101 includes inspection numbers n=1, 2, and 3. The maximum value of inspection number n is 3. Inspection items with n=4-8 will be described later in a modified example.

[0024] Therefore, in step S104, the inspection unit 13 selects an inspection item to be processed. Here, the inspection item with inspection number n=1 is selected. Then, in step S105, the inspection unit 13 determines the inspection state that the wind power generation facility 401 should take and the inspection route for the unmanned aerial vehicle 201 so that the photographing state is suitable for n=1.

[0025] n=1 is a dynamic visual inspection for inspecting the power generation driving status. As shown in Fig. 4, the inspection unit 13 determines an inspection route that goes around the wind power generation equipment 401 twice. The inspection unit 13 also determines the rotor to be in a driving state as the state that the wind power generation equipment 401 should be in.

[0026] Next, in step S106, the equipment control unit 15 controls the wind power generation equipment 401 to an inspection state so that it is in a state suitable for photographing n=1. Since the rotor is controlled to a driving state, the blades 44 continue to rotate. In addition, the nacelle yaw φ remains at 0°.

[0027] Then, in step S107, inspection photography is performed by the unmanned aerial vehicle 201. In this step, first, the flight control unit 14 moves the unmanned aerial vehicle 201 to the start position of the inspection route. The start position of the inspection route is set, for example, 100 m north of the center position of the hub so that the three blades 44 can be photographed from the front. From there, the unmanned aerial vehicle 201 circles the wind power generation facility 401 twice, maintaining a constant distance from the wind power generation facility 401, for example, 100 m. At the same time, the photography device 24 photographs the wind power generation facility 401.

[0028] When inspection photography for n=1 is completed, in step S108 the inspection unit 13 determines whether there are any unprocessed inspection items. Since inspection items n=2 and 3 still remain, the inspection unit 13 returns to step S104 and selects inspection item n=2. Then, in step S105, the inspection unit 13 determines the inspection status of the wind power generation facility 401 and the inspection route for the unmanned aerial vehicle 201 so that the photography conditions are suitable for n=2.

[0029] Inspection number n=2 is a static visual inspection. As shown in FIG. 4 , inspection unit 13 determines the inspection route as a route that circles wind power generation equipment 401 twice. In addition, inspection unit 13 determines the rotor to be in a stopped state as the inspection state that wind power generation equipment 401 should be in. Unmanned aerial vehicle 201 is controlled to maintain a fixed distance, for example, 100 m, from wind power generation equipment 401. The starting position of the inspection route is the same as for n=1.

[0030] Next, in step S106, the equipment control unit 15 controls the wind power generation equipment 401 to an inspection state so that it is in a state suitable for taking images of n=2. Since the rotor is controlled to be in a stopped state, the blades 44 are stopped. In addition, the nacelle yaw φ remains at 0°.

[0031] Then, in step S107, inspection photography is performed by the unmanned aerial vehicle 201. In this step, first, the flight control unit 14 moves the unmanned aerial vehicle 201 to the start position of the inspection route. The start position of the inspection route is set, for example, 100 m north of the center position of the hub so that the three blades 44 can be photographed from the front. From there, the unmanned aerial vehicle 201 circles the wind power generation facility 401 twice, maintaining a constant distance from the wind power generation facility 401, for example, 100 m. At the same time, the photography device 24 photographs the wind power generation facility 401.

[0032] When inspection photography for n=2 is completed, in step S108 the inspection unit 13 determines whether there are any unprocessed inspection items. Since inspection item n=3 still remains, the inspection unit 13 returns to step S104 and selects inspection item n=3. Then, in step S105, the inspection unit 13 determines the inspection status of the wind power generation facility 401 and the inspection route for the unmanned aerial vehicle 201 so that the photography conditions are suitable for n=3.

[0033] Inspection number n=3 is a static visual inspection that takes shadows into consideration. In this inspection, the shooting conditions include the solar orientation. If shadows are included in the captured video of the wind power generation facility 401, the accuracy of detecting failures or damage to the wind power generation facility 401 through video analysis may decrease. Therefore, this inspection aims to obtain inspection video without shadows.

[0034] 5 shows, by means of a matte finish, the shadows cast on various parts of the wind power generation facility 401 depending on the solar orientation. Basically, the side of the wind power generation facility 401 facing away from the sun is in shadow. In addition, there are cases where a specific blade 44 casts a shadow on another blade 44 or the nacelle 45, or where the shadow is cast on the blade 44 depending on the position of the nacelle 45.

[0035] The inspection unit 13 determines the inspection route as a route that circles the wind power generation facility 401 twice. The inspection unit 13 also determines the rotor to be in a stopped state as the inspection state that the wind power generation facility 401 should be in, and determines the nacelle yaw φ to match the solar orientation. When the sun is at its highest point in the sky, the nacelle 45 faces south, so the nacelle yaw φ is determined to be 180°. In this way, the nacelle yaw is determined so that the inspection point of the wind power generation facility 401 faces the sun.

[0036] Next, in step S106, the equipment control unit 15 controls the wind power generation equipment 401 to an inspection state suitable for photographing n=3. The rotor is controlled to a stopped state, and the blades 44 are stopped. In addition, the nacelle yaw φ is adjusted to 180°, and the nacelle 45 faces the sun as shown in FIG. 7. This prevents shadows from falling on the front surfaces of the blades 44.

[0037] Then, in step S107, inspection photography is performed by the unmanned aerial vehicle 201. In this step, the flight control unit 14 first moves the unmanned aerial vehicle 201 to the start position of the inspection route. The start position of the inspection route is set 100 m south of the center position of the hub with the nacelle 45 inverted (nacelle yaw φ = 180°). This makes it possible to photograph the three blades 44 from the front. This state is shown in FIG. 7. From there, as shown in FIG. 8, the unmanned aerial vehicle 201 makes two laps around the wind power generation facility 401 along an inspection route 81 with a radius of 200 m. The unmanned aerial vehicle 201 photographs the blades 44 and nacelle 45 and acquires inspection video (moving or still images) while circling the wind power generation facility 401 from the start position of the inspection route 81 on the same plane at the same height. Thereafter, unmanned aerial vehicle 201 moves to a position higher by half the blade length and again circles around wind power generation facility 401, photographing blades 44 and nacelle 45 and acquiring inspection footage. When unmanned aerial vehicle 201 takes still images as inspection footage, it may take the images while standing still at the shooting position.

[0038] When the inspection photography for n=3 is completed, in step S108, the inspection unit 13 determines whether there are any unprocessed inspection items. Since all inspection items have been completed, the processing of the equipment inspection device 101 proceeds from step S108 to step S109. In step S109, the inspection unit 13 transmits the inspection video captured by the photography device 24 to the command center 301 via the communication device 23. At this time, the inspection unit 13 may associate the inspection date and time, illuminance, the ID of the wind power generation equipment 401, the position of each part of the wind power generation equipment 401, its operating status, the position of the unmanned aerial vehicle 201, and the like as attribute information with the inspection video. In this way, the inspection video is accumulated in the data collection unit 33 of the command center 301. The video analysis unit 34 analyzes the inspection video using a predetermined analysis logic to detect abnormalities in the wind power generation equipment. A convolutional neural network (CNN) that has learned the damage state may be used as the predetermined analysis logic. Furthermore, the video analysis unit 34 may analyze the likelihood of damage rather than determining whether or not damage exists. In this case, if the analyzed likelihood of damage is equal to or greater than a predetermined threshold, an image of the relevant location may be presented to the user, and the user may check the image to make a final determination as to whether or not damage exists.

[0039] Thereafter, in step S110, the flight control unit 14 receives an instruction from the inspection unit 13 and returns the unmanned aerial vehicle 201 to a predetermined location. The return location of the unmanned aerial vehicle 201 may be the command center 301 or another location. Note that in the case of an inspection plan that includes inspecting multiple wind power generation facilities 401, the flight control unit 14 may fly the unmanned aerial vehicle 201 to the next wind power generation facility 401 to be inspected and continue similar inspection filming. The process of transmitting the inspection video in step S109 may be executed during or after the return in step S110. This completes the processing of the equipment inspection device 101.

[0040] <A-3. First Modification> For the inspection item n=3, inspection photography was performed with the nacelle 45 facing the sun. In this case, the front surfaces of the blades 44 were unshadowed, but the back surfaces were shadowed. Therefore, the nacelle 45 may be oriented not only toward the sun but also in multiple directions, such as 90°, 180°, or 270° relative to the sun, and two rounds of inspection photography may be performed with the nacelle 45 facing each direction. This makes it possible to obtain inspection footage without shadows over the entire wind power generation facility 401. In other words, the inspection state of the wind power generation facility 401 includes multiple inspection states with different yaw angles of the nacelle 45, and the flight control unit 14 flies the unmanned aerial vehicle 201 along the inspection route based on the position information each time the state of the wind power generation facility 401 switches between multiple inspection states.

[0041] Furthermore, when photographing by rotating the nacelle 45 in multiple directions, the nacelle yaw angle does not need to be determined based on the direction of the sun. For example, the nacelle yaw φ = φs at the time the unmanned aerial vehicle 201 arrives near the wind power generation facility 401 may be used as the base point, and the nacelle yaw φ may be set to φs, φs + 90°, φs + 180°, and φs + 270°, and inspection photographing may be performed two times with the nacelle 45 facing each direction. This reduces the number of times the nacelle 45 needs to be rotated, thereby saving energy and shortening the inspection time. In this case, the condition acquisition unit 12 does not need to acquire the sun's orientation as a photographing condition. Instead, the condition acquisition unit 12 acquires whether or not the wind power generation facility 401 is exposed to sunlight as a photographing condition. Whether or not sunlight is irradiated can be acquired by analyzing video of the sun or the wind power generation facility 401 captured by the unmanned aerial vehicle 201 that has arrived near the wind power generation facility 401.

[0042] <A-4. Second Modification> In the second modification, inspection numbers n=4 and 5 will be described. Inspection numbers n=4 and 5 are partial inspections. In the partial inspection of n=4, each part, such as the blade 44, nacelle 45, and tower 46, is photographed individually. The inspection route is a route that allows each of these parts to be photographed individually, and is closer to the subject to be photographed, for example, up to 25 m, compared to the inspection routes of n=1, 2, and 3. This allows the part to be inspected to appear larger in the inspection video.

[0043] 9 shows an example of an inspection route 81 for the unmanned aerial vehicle 201 during a partial inspection of the nacelle 45. The inspection route 81 is a route that traces a circle with a radius of 25 m from the center of the nacelle 45 on a vertical plane that includes the center of the nacelle 45. Note that photography is omitted below the circle to prevent the unmanned aerial vehicle 201 from colliding with the tower 46. For example, there is a 45-degree notch, and the inspection route 81 is an arc of 135°. If the nacelle yaw φ=0°, the shadow of the blade 44 will not be cast on the nacelle 45.

[0044] 10 shows another example of inspection route 81 of unmanned aerial vehicle 201 during partial inspection of nacelle 45. This inspection route 81 is a circular route with a radius of 25 m from the center of nacelle 45 on a horizontal plane including the center of nacelle 45. In addition, at this time, the rotation direction of blade 44 is adjusted so that one of blades 44 faces directly downward so that unmanned aerial vehicle 201 does not collide with blade 44.

[0045] Furthermore, if the inspection route 81 is a route that circles the wind power generation facility 401 at a lower position than that shown in FIG. 10, it is possible to perform a partial inspection of the tower 46.

[0046] 11 and 12 show examples of inspection route 81 of unmanned aerial vehicle 201 for partial inspection of blade 44. When photographing the underside of blade 44, inspection route 81 is an orbital circle with a radius of 20 m and a radius of 40 m, centered at a position 25 m away from the hub in the opposite direction to the nacelle, as shown in FIG. 11 . At this time, nacelle yaw φ remains at 0°. When photographing the front side of blade 44, nacelle 45 is rotated toward sun 80 (nacelle yaw φ = 180°), as shown by arrow 71 in FIG. 12 . Inspection route 81 is an orbital circle with a radius of 20 m and a radius of 40 m, centered at a position 25 m away from the hub in the direction of the nacelle, as shown in FIG. 12 .

[0047] The inspection route 81 shown in Figures 11 and 12 is merely an example, and other inspection routes 81 may be used in accordance with the inspection specifications. For example, a spiral inspection route 81 may be used instead of two circular inspection routes. Also, as shown in Figure 13, an inspection route 81 that flies along the longitudinal direction of each blade 44 may be used. Also, as shown in Figure 14, an inspection route 81 that circumnavigates the blades 44 one by one may be used.

[0048] In the partial inspection where n=5, the blades 44 are photographed while changing the pitch angle α of the blades 44. The inspection route 81 is a route that allows the blades 44 to be photographed individually, and for example, the inspection route 81 shown in Figure 13 or 14 is adopted. The unmanned aerial vehicle 201 approaches the blades 44 to within 25 m, for example.

[0049] <A-5. Third Modification> In the third modification, the wind direction is taken into consideration when controlling the orientation of the nacelle 45. That is, the imaging condition information includes information about the wind direction in the wind power generation facility 401.

[0050] From the viewpoint of improving inspection accuracy, it is desirable for the unmanned aerial vehicle 201 to take photographs as close as possible to the wind power generation facility 401. However, if the unmanned aerial vehicle 201 gets too close, there is a possibility that the unmanned aerial vehicle 201 will be blown by the wind and come into contact with the wind power generation facility 401.

[0051] Therefore, in this modification, the condition acquisition unit 12 acquires information about the wind direction at the wind power generation facility 401 from a sensor mounted on the unmanned aerial vehicle 201, a sensor provided at the wind power generation facility 401, or the command center 301. Based on the wind direction information, the inspection unit 13 determines the nacelle yaw φ so that the inspection portion of the wind power generation facility 401 faces downwind, and determines an inspection route 81 for photographing the inspection portion from downwind. In this way, the inspection unit 13 determines, as the inspection state, the yaw angle of the nacelle of the wind power generation facility so that the inspection portion of the wind power generation facility 401 faces a predetermined direction with respect to the wind direction.

[0052] Figure 15 shows a case where the underside of blade 44 is the inspection part. In Figure 15, the wind direction is from north to south, as indicated by arrow 82. The nacelle yaw φ is set to 0°, and unmanned aerial vehicle 201 photographs the underside of blade 44 from a position 20 m downwind. As a result, even if the wind suddenly becomes stronger, unmanned aerial vehicle 201 simply moves away from wind power generation equipment 401, and there is no risk of it coming into contact with wind power generation equipment 401.

[0053] Figure 16 shows a case where the inspection part is the front surface of blade 44. In Figure 16, the wind direction is also assumed to be from north to south, as indicated by arrow 82. The nacelle yaw φ is set to 180°, and unmanned aerial vehicle 201 photographs the front surface of blade 44 from a position 20 m downwind.

[0054] 15 and 16, the distance between unmanned aerial vehicle 201 and blade 44 is set to 20 m. This distance may be increased as the wind speed increases. In other words, the shooting condition information may include information on wind speed in addition to wind direction.

[0055] Alternatively, the nacelle yaw φ may be adjusted so that the nacelle 45 is perpendicular to the wind direction, and the unmanned aerial vehicle 201 may photograph the front or back surfaces of the blades 44 from a position 20 m away, directly facing them. In this case, because the photographing direction of the unmanned aerial vehicle 201 is perpendicular to the wind direction, there is little chance of the unmanned aerial vehicle 201 coming into contact with the wind power generation facility 401 even if the wind strength suddenly increases or decreases and the unmanned aerial vehicle 201 is no longer able to maintain its position.

[0056] <A-6. Fourth Modification> In the fourth modification, the attitude and inspection route of the wind power generation facility 401 are determined taking into consideration both the solar orientation and wind direction. That is, the imaging condition information includes information on the solar orientation and wind direction at the wind power generation facility 401.

[0057] 17 and 18 show inspection routes for blade inspections that take into account both the sun's direction and the wind direction. In these figures, the sun's direction is south. By orienting the nacelle 45 south (nacelle yaw φ = 180°), shadows are avoided on the front surfaces of the blades 44. Furthermore, the rotation angle θ of the blades 44 to be inspected is controlled so that the blades 44 face directly upward. An inspection route 81 is defined as an elliptical route that circles the blades 44. The wind direction, represented by the arrow 82, is from north to south in FIG. 17 and from south to north in FIG. 18. The distance from the blades 44 on the inspection route 81 is set to 20 m in the downwind direction and 30 m in the upwind direction. In this way, by ensuring a larger margin from the blades 44 in the upwind direction than in the downwind direction, the possibility of the unmanned aerial vehicle 201 coming into contact with the blades 44 can be reduced.

[0058] As described above, in locations where the shooting direction of the unmanned aerial vehicle 201 is perpendicular to the wind direction, the possibility of the unmanned aerial vehicle 201 coming into contact with the wind power generation facility 401 is low. Therefore, in the examples of Figures 17 and 18, in locations on the inspection route 81 where the shooting direction of the unmanned aerial vehicle 201 is perpendicular to the wind direction, the distance to the blades 44 may be shorter than in locations on the downwind side. Figure 19 shows such an inspection route 81.

[0059] <A-7. Fifth Modification> In the fifth modification, inspection number n=6 will be described. Inspection number n=6 is a detailed inspection of a cautionary area. A cautionary area is an area that has been determined to be suspected of damage based on the inspection footage of n=1 and 2. In this case, information about the cautionary area is included in the imaging condition information. In this inspection, the equipment control unit 15 stops the rotation of the blades 44. The pitch angle α of the blades 44 may be changed to make it easier to image the cautionary area. The nacelle yaw may also be changed according to the orientation of the sun 80. The inspection route 81 is a route that allows imaging of the cautionary area, and the unmanned aerial vehicle 201 approaches to within 10 m of the cautionary area, for example.

[0060] <A-8. Sixth Modification> In the sixth modification, inspection number n=7 will be described. Inspection number n=7 is a drive system inspection. In the drive system inspection, it is inspected whether the nacelle 45 or the rotor is operating normally. In this case, the imaging condition information includes information that the drive system will be inspected as part of the inspection content of the wind power generation equipment 401. The inspection planning unit 32 may decide to carry out inspection number n=7 when sensor information indicating an abnormality in the drive system is acquired from the wind power generation equipment 401, or may decide to carry out inspection number n=7 based on the analysis results of the inspection video of inspection number n=1.

[0061] The inspection route is a route that allows the drive system to be photographed, and the subject to be photographed is approached to a distance of, for example, 20 m.

[0062] To check the rotation of the nacelle 45, the unmanned aerial vehicle 201 is caused to hover in a position suitable for checking the operation of the nacelle 45, for example, 20 m above the nacelle 45, and then the equipment control unit 15 issues a drive command to the wind power generation equipment 401 to rotate the nacelle 45. The imaging device 24 takes video of the rotation status of the nacelle 45. This allows the video analysis unit 34 to inspect whether the nacelle 45 is operating in accordance with the drive command and whether there is any rattle in the rotation.

[0063] To check rotor rotation, the unmanned aerial vehicle 201 is hovered in a position suitable for checking rotor operation, for example, 20 m away from the hub 47, facing the rotor. Then, the equipment control unit 15 issues a command to the wind power generation equipment 401 to change the rotor from a stopped state to a rotating state, and then to a stopped state again. The camera device 24 captures video of the rotor rotation. This allows the video analysis unit 34 to inspect whether the rotor is operating as instructed and whether there is any rattle in the rotation.

[0064] When checking the drive of the pitch angle α of the blades 44, the unmanned aerial vehicle 201 is caused to hover at a position suitable for checking the drive of the pitch angle α, for example, a position 20 m away from the center position of the blades 44 in the longitudinal direction and directly facing the blades 44, and then the equipment control unit 15 issues a drive command to the wind power generation equipment 401 to change the pitch angle α of the blades 44. The imaging device 24 captures images of the drive of the pitch angle α of the blades 44. This allows the image analysis unit 34 to inspect whether the blades 44 are changing the pitch angle α as instructed.

[0065] <A-9. Seventh Modification> In the seventh modification, inspection number n=8 will be described. Inspection number n=8 is a sensor system inspection. In the sensor system inspection, it is inspected whether sensors that measure the rotation angle or rotation speed of the nacelle 45 or rotor are operating normally. In this case, the imaging condition information includes information that the drive system sensors will be inspected as part of the inspection content of the wind power generation facility 401.

[0066] The control of the inspection route 81 and the wind power generation facility 401 is the same as in the case of n=7.

[0067] When inspecting the sensors of the nacelle 45, the video analysis unit 34 acquires sensor information related to the operation of the nacelle 45 from the wind power generation equipment 401, such as information from an azimuth sensor (geomagnetic sensor) or a rotational speed sensor, and compares this with the inspection video captured by the imaging device 24 to detect any sensor abnormalities.

[0068] When inspecting the rotor sensor, the video analysis unit 34 acquires sensor information related to the rotor operation from the wind power generation equipment 401, such as measurement information from a rotation angle sensor or rotation speed sensor, and compares this with the inspection video captured by the imaging device 24 to detect any sensor abnormalities.

[0069] <A-10. Other Modifications> The wind power generation facility 401 may be equipped with a power supply facility for the unmanned aerial vehicle 201. The power supply facility performs authentication in response to a request from the unmanned aerial vehicle 201, and supplies power to the unmanned aerial vehicle 201 with or without contact before, during, or after inspection photography. The flight control unit 14 controls the flight of the unmanned aerial vehicle 201 so that the unmanned aerial vehicle 201 can receive power from the power supply facility. The cruising range of the unmanned aerial vehicle 201 is limited by the amount of stored power. By receiving a power supply from the wind power generation facility 401, the unmanned aerial vehicle 201 can expand the service area in which the unmanned aerial vehicle 201 can perform inspection photography, centered on the standby facility.

[0070] It is not necessary to provide power supply equipment for all of the multiple wind power generation facilities 401 in the facility inspection system 1001. For example, if multiple wind power generation facilities 401 are installed in close proximity, such as within a 10 km radius, only one of the wind power generation facilities 401 may be provided with power supply equipment.

[0071] The inspection video captured by the unmanned aerial vehicle 201 is transmitted from the unmanned aerial vehicle 201 to the command center 301, but may also be transmitted from the unmanned aerial vehicle 201 to the command center 301 via the wind power generation facility 401. In this case, the unmanned aerial vehicle 201 transmits the inspection video to the wind power generation facility 401, so the communication distance is shorter than when transmitting to the command center 301, and power consumption of the unmanned aerial vehicle 201 is reduced.

[0072] In addition, communication between the unmanned aerial vehicle 201 and the wind power generation facility 401 may be performed via the command center 301.

[0073] The equipment inspection system 1001 may include, in addition to the unmanned aerial vehicle 201 that performs inspection photography, another unmanned aerial vehicle (hereinafter referred to as a "monitoring unmanned aerial vehicle") that monitors the unmanned aerial vehicle 201. The monitoring unmanned aerial vehicle monitors and photographs the unmanned aerial vehicle 201 that is performing inspection photography.

[0074] The monitoring unmanned aerial vehicle waits at a predetermined position relative to the unmanned aerial vehicle 201, for example, 200 meters above the ground, captures video or still images of the relative positions of the unmanned aerial vehicle 201 and the wind power generation facility 401 during inspection filming, and transmits these to the command center 301 as evidence video of the inspection status. At this time, information on the date and time the evidence video was captured may be linked to the evidence video as attribute information of the evidence video. Additionally, location information of the monitoring unmanned aerial vehicle and the unmanned aerial vehicle 201 and status information of the wind power generation facility may be linked to the evidence video as attribute information. This allows the video analysis unit 34 to compare inspection video captured at the same time with the evidence video to determine the authenticity of the inspection video and to inspect the wind power generation facility 401 using only highly authentic inspection video. Furthermore, the video analysis unit 34 can quickly detect abnormalities, such as abnormal attitude or position, in the unmanned aerial vehicle 201.

[0075] 1 , the inspection unit 13 and the equipment control unit 15 are installed in the unmanned aerial vehicle 201, but they may also be installed in the command center 301. The components of the position acquisition unit 11, the condition acquisition unit 12, the inspection unit 13, the flight control unit 14, the equipment control unit 15, the data collection unit 33, the inspection planning unit 32, and the video analysis unit 34 may be installed in any of the command center 301, the unmanned aerial vehicle 201, and the wind power generation facility 401, as long as there is no contradiction. For example, the video analysis unit 34 may be installed in the wind power generation facility 401 or the unmanned aerial vehicle 201.

[0076] The inspection unit 13 may acquire future weather information for the wind power generation facility 401 and determine the departure time of the unmanned aerial vehicle 201 from its departure point based on the future weather information and the time required for the unmanned aerial vehicle 201 to reach the wind power generation facility 401 from its departure point. The weather information may include, for example, information on wind speed or precipitation. For example, a wind speed of less than 5 m / s is set as an acceptable condition for photography, and the time required for the unmanned aerial vehicle 201 to reach the wind power generation facility 401 is set to 15 minutes. According to the weather information, the wind speed at the wind power generation facility 401 is currently 5 m / s or higher and will be less than 5 m / s in one hour. In this case, the inspection unit 13 sets the departure time of the unmanned aerial vehicle 201 to 45 minutes in the future. This allows the unmanned aerial vehicle 201 to begin inspection photography immediately after arriving at the wind power generation facility 401.

[0077] The inspection unit 13 may acquire future weather information for the wind power generation facility 401 during inspection photography, and may stop the inspection photography by the unmanned aerial vehicle 201 based on a comparison of the current weather information with the future weather information. For example, if better weather conditions are expected within an allowable time, the unmanned aerial vehicle 201 may suspend the inspection photography and wait, and then resume the inspection photography once the better weather conditions are achieved. Here, the allowable time is, for example, one hour. It is desirable to stop the inspection photography when the wind speed is high or when there is heavy rainfall.

[0078] The shooting condition information may include information on the solar altitude in addition to the solar azimuth. In this case, the inspection unit 13 can prevent the shadow of the unmanned aerial vehicle 201 from being included in the inspection video by determining the inspection route for the unmanned aerial vehicle 201 so that the unmanned aerial vehicle 201 does not come between the sun and the inspection location of the wind power generation facility 401.

[0079] In the first embodiment, the control of the orientation of the nacelle 45 taking into account the solar azimuth has been described. This assumes a sunny weather. In cloudy weather, no shadows are cast, so there is no need to control the orientation of the nacelle 45 taking into account the solar azimuth. The unmanned aerial vehicle 201 is equipped with lighting, and in dark conditions, inspection photography can be performed by illuminating the inspection area of ​​the wind power generation facility 401 with the lighting.

[0080] <A-11. Effects> The equipment inspection device 101 according to the first embodiment includes a position acquisition unit 11 that acquires position information of the unmanned aerial vehicle 201 that performs inspection photography while flying and photographing inspection points of the wind power generation equipment 401 using the mounted imaging device 24, a condition acquisition unit 12 that acquires imaging conditions necessary for inspecting and photographing the wind power generation equipment, an inspection unit 13 that determines an inspection state, which is the state of the wind power generation equipment 401 that should be taken during inspection photography based on the imaging conditions, and determines an inspection route, which is the flight route of the unmanned aerial vehicle 201 during inspection photography, an equipment control unit 15 that controls the wind power generation equipment 401 to be in the inspection state, and a flight control unit 14 that causes the unmanned aerial vehicle 201 to fly the inspection route based on the position information while the wind power generation equipment 401 is controlled to be in the inspection state. The inspection unit 13 causes the imaging device 24 to photograph the wind power generation equipment 401 while the unmanned aerial vehicle 201 is flying along the inspection route. In this way, the equipment inspection device 101 controls the wind power generation equipment 401 so that the inspection location is easy to photograph, and then performs inspection photography, so that inspection footage can be captured that makes it easy to inspect the wind power generation equipment 401, and high-precision inspection can be performed using this inspection footage.

[0081] <B. Embodiment 2> <B-1. Configuration> Fig. 20 is a diagram showing the configuration of an equipment inspection system 1002 according to embodiment 2. The equipment inspection system 1002 is configured to include an unmanned aerial vehicle 202 such as a drone, a command center 301, and a wind power generation facility 402 to be inspected.

[0082] The unmanned aerial vehicle 202 is configured to include a first GNSS 25, a flight device 22, a communication device 23, an imaging device 24, and an equipment inspection device 102. The wind power generation facility 402 includes a second GNSS 48 in addition to the configuration of the wind power generation facility 401 according to embodiment 1. The equipment inspection device 102 has the same configuration as the equipment inspection device 101 according to embodiment 1.

[0083] Thus, in this embodiment, a GNSS is provided in both the unmanned aerial vehicle 202 and the wind power generation facility 402. The first GNSS 25 and the second GNSS 48 have superior positioning accuracy to the GNSS 21 provided in the unmanned aerial vehicle 201 according to embodiment 1, and have positioning performance on the order of several centimeters. The first GNSS 25 and the second GNSS 48 may use any high-precision positioning method, such as a method compatible with the Centimeter Level Augmentation Service (CLAS) or a Real Time Kinematic (RTK) method.

[0084] The equipment inspection device 102 detects the exact relative positions of the unmanned aerial vehicle 202 measured by the first GNSS 25 and the wind power generation equipment 402 measured by the second GNSS 48 based on the position information of the unmanned aerial vehicle 202 and the position information of the wind power generation equipment 402 measured by the second GNSS 48, and causes the unmanned aerial vehicle 202 to perform inspection photography.

[0085] <B-2. Operation> Unmanned aerial vehicle 202 can approach wind power generation facility 402 much closer than unmanned aerial vehicle 201 according to embodiment 1. For example, unmanned aerial vehicle 202 can approach wind power generation facility 402 to a distance of 5 m or 10 m. If there is no wind, unmanned aerial vehicle 202 can also come into contact with or land on wind power generation facility 402. When unmanned aerial vehicle 202 comes into contact with or lands on wind power generation facility 402, unmanned aerial vehicle 202 is preferably equipped with a proximity sensor or an image processing measurement sensor, and information from these sensors is also used to measure the precise relative position of unmanned aerial vehicle 202 to wind power generation facility 402.

[0086] Fig. 21 is a flowchart showing the operation of the equipment inspection device 102. Compared with the flow of Fig. 4 described in the first embodiment, the flow of Fig. 21 includes step S107A instead of step S107.

[0087] 22 shows the coordinate system of the local system. The point where the longitudinal direction of the nacelle 45 intersects with the center of rotation of the nacelle 45 is defined as the origin O, the direction toward the hub 47 is defined as the x direction, and the direction directly above is defined as the z direction. The second GNSS 48 may be installed anywhere in the wind power generation facility 402, but here it is assumed to be installed at an absolute position Q (-6 m, 0, 0) at the rear of the nacelle 45.

[0088] The inspection unit 13 acquires attitude information from the wind power generation equipment 402, and based on the nacelle yaw φ included in the attitude information, can calculate the absolute position 6 m ahead along the direction of the nacelle 45 from the absolute position Q as the origin O of the local system. Therefore, the relative position PR of the unmanned aerial vehicle 202 with the origin O as the base point can be determined from the absolute position P of the first GNSS 25 installed on the unmanned aerial vehicle 202, the absolute position Q, and the nacelle yaw φ.

[0089] Furthermore, the inspection unit 13 can determine the accurate relative positions of the unmanned aerial vehicle 202 and each part of the wind power generation facility 402 by using the rotation angle θ and pitch angle α of the blades 44 included in the attitude information of the wind power generation facility 402 and specification information related to the shape of the wind power generation facility 402. If the positional accuracy of the first GNSS 25 and the second GNSS 48 is insufficient, the inspection unit 13 can also move the position of the unmanned aerial vehicle 202 and supplement the positional accuracy by using specific photographing positions of the wind power generation facility 402 photographed from multiple absolute positions Pn.

[0090] If the second GNSS 48 is installed at the position of the origin O, the absolute position of the second GNSS 48 can be set as the origin O.

[0091] In step S107A, the flight control unit 14 moves the unmanned aerial vehicle 202 to the start position of the inspection route and flies the unmanned aerial vehicle 202 along the inspection route. At the same time, the imaging device 24 captures an image of the wind power generation facility 401.

[0092] At this time, the flight control unit 14 obtains the absolute position Q of the second GNSS 48 and attitude information of the wind power generation facility 402 from the wind power generation facility 402 via the communication device 23. The attitude information of the wind power generation facility 402 includes the rotation angle θ and pitch angle α of the blades 44, and the nacelle yaw φ. Furthermore, the flight control unit 14 obtains the absolute position P(x, y, z) of the unmanned aerial vehicle 202 from the first GNSS 25, and calculates the relative position of each part of the wind power generation facility 402 and the unmanned aerial vehicle 202 with an accuracy of centimeters, based on the relative position PR of the unmanned aerial vehicle 202 with respect to a specific position O of the wind power generation facility 402 as the origin, and the specifications and attitude information of the wind power generation facility 402.

[0093] As a result, unmanned aerial vehicle 202 can perform inspection and photography at a much closer distance to each part of wind power generation facility 402 than in embodiment 1, for example, at a distance of approximately 5 m. FIG. 23 shows a list of inspection items in this embodiment. In this embodiment, in the partial inspections of inspection numbers n=4 and 5 and the detailed inspection of inspection number n=6 when an abnormality occurs, unmanned aerial vehicle 202 can perform inspection and photography at a distance of approximately 5 m to the inspection points of wind power generation facility 402. As a result, clear inspection images can be obtained, improving the accuracy of failure analysis by video analysis unit 34.

[0094] 24 and 25 show inspection route 81 of unmanned aerial vehicle 202 for inspection number n=6 (detailed inspection of suspicious areas). In these figures, suspicious area QX exists on the front surface of blade 44.

[0095] In the example of Figure 24, the inspection route 81 approaches the caution area QX to a distance of 5 m, and is a route that flies in a straight line along the length of the blade 44. The rotation angle θ of the blade 44 where the caution area QX is located is adjusted to 90° in Figure 24. This makes the inspection route 81 a route that does not change vertically, making flight control easier for the unmanned aerial vehicle 202.

[0096] In the example of Figure 25, the inspection route 81 approaches the caution area QX to a distance of 5 m and circles around the blade 44. The rotation angle θ of the blade 44 where the caution area QX is located is adjusted to 0° in Figure 25. This makes the inspection route 81 a route with no vertical changes, making flight control easier for the unmanned aerial vehicle 202.

[0097] 24 and 25, the caution area QX is located on the front surface of the blade 44, and therefore the nacelle 45 faces the sun so as not to cast a shadow on the front surface of the blade 44. If the caution area QX is located on the rear surface of the blade 44, the nacelle 45 may be rotated 180° so as not to cast a shadow on the rear surface of the blade 44.

[0098] Furthermore, if required by the inspection specifications, the rotor may be rotated while the unmanned aerial vehicle 202 follows the rotation of the rotor to photograph a specific portion.

[0099] <B-3. First Modification> Figure 26 is a block diagram showing the configuration of unmanned aerial vehicle 202A according to a first modification of embodiment 2. Unmanned aerial vehicle 202A includes support mechanism 26 in addition to the configuration of unmanned aerial vehicle 202. Support mechanism 26 is a mechanism that supports inspection photography by unmanned aerial vehicle 202A. Support mechanism 26 includes, for example, a wiper mechanism that wipes away raindrops or dirt adhering to an inspection location of wind power generation facility 402, a blowing mechanism, or a contact sensor mechanism that checks for unevenness in the inspection location. The processing performed by support mechanism 26 is also referred to as support processing.

[0100] For example, a location that the video analysis unit 34 determines to be a caution area after analyzing the inspection video may simply be covered in raindrops or dirt. Therefore, when a caution area is found, the inspection unit 13 controls the wiper mechanism to wipe the caution area. The inspection unit 13 then controls the flight control unit 14 and the imaging device 24 to photograph the caution area again. If the caution area is simply a location where raindrops or dirt have been attached, the wiper mechanism will remove the raindrops or dirt, and the video analysis unit 34 can determine that there is no damage to the caution area by checking the inspection video in the cleaned state.

[0101] The inspection unit 13 may also use a contact sensor to sense the presence or absence of unevenness in the caution area. The presence or absence of unevenness may be linked to the inspection video as attribute information. This allows the video analysis unit 34 to determine that the caution area is damaged if it is uneven.

[0102] When a contact sensor is used to detect a critical area of ​​blade 44 or a wiper mechanism is used to wipe it, unmanned aerial vehicle 202A may land on blade 44. In this case, blade 44 may have its rotation angle θ or pitch angle α adjusted so that unmanned aerial vehicle 202A can easily land horizontally.

[0103] <B-4. Second Modification> As shown in Fig. 27 , the tower 46 is subject to roll, pitch, or yaw due to the influence of wind. When the wind power generation facility 402 is installed offshore, the tower 46 is not necessarily fixed, and therefore the above phenomenon becomes particularly pronounced due to the influence of waves or wind. Figs. 28 to 30 respectively show the yaw, roll, and pitch that occur in the tower 46 of the offshore wind power generation facility 402. Figs. 28 to 30 show the absolute position measured by the second GNSS 48 at a certain time as Q, the absolute position measured by the second GNSS 48 at the next time as Q', and the time-series change Q'-Q=Q(t) that is the fluctuation in absolute position between these two times.

[0104] The inspection unit 13 predicts fluctuations in roll, pitch, or yaw of the tower 46 based on the time-series change Q(t) in the absolute position measured by the second GNSS 48. The pitch and roll fluctuations (amplitude or frequency) of the tower 46 can be found from the displacement of the absolute position Q on a spherical surface centered on the bottom surface of the tower 46. If the second GNSS 48 is installed at a position away from the center of rotation of the nacelle 45, the yaw of the tower 46 can be found from the displacement of the absolute position Q in the horizontal plane. Furthermore, even when pitch, roll, and yaw fluctuations are combined, they can be found from an equation using each parameter as a variable.

[0105] The inspection unit 13 then predicts changes in the absolute position of each part of the wind power generation facility 402 based on the predicted roll, pitch, or yaw fluctuations of the tower 46. In this way, the inspection unit 13 acquires a time series of position information from the second GNSS 48, predicts the future pitch angle and roll angle of the tower 46 of the wind power generation facility 402 based on the time series of position information from the second GNSS 48, and creates an inspection route based on the future pitch angle and roll angle of the tower 46, the position information of the unmanned aerial vehicle 202, the position information of the second GNSS 48, and the operating state of the wind power generation facility 402. Alternatively, the second GNSS 48 is installed to avoid the center of rotation of the nacelle 45 of the wind power generation facility 402, and the inspection unit 13 acquires a time series of position information from the second GNSS 48, predicts a future yaw angle of the nacelle 45 based on the time series of the position information from the second GNSS, and creates an inspection route for the unmanned aerial vehicle 202 based on the future yaw angle of the nacelle 45, the position information of the unmanned aerial vehicle 202, the position information of the second GNSS 48, and the operating status of the wind power generation facility 402. This allows the flight control unit 14 to fly the unmanned aerial vehicle 202 while tracking changes in the position of the inspection location. By using the first GNSS 25 installed on the unmanned aerial vehicle 202 and performing high-precision positioning, and the second GNSS 48 installed on the wind power generation facility 402 and performing high-precision positioning, inspection photography can be performed by moving the position of the unmanned aerial vehicle 202 to track movements of the tower 46.

[0106] <B-5. Effects> In the equipment inspection device 102 according to the second embodiment, the position acquisition unit 11 acquires position information of the unmanned aerial vehicle 202 measured by a first GNSS 25 installed on the unmanned aerial vehicle 202 and having a positioning accuracy on the order of centimeters, and the inspection unit 13 acquires, from the wind power generation facility 402, position information of the specific position measured by a second GNSS 48 installed at a specific position of the wind power generation facility 402 and having a positioning accuracy on the order of centimeters, and the operating status of the wind power generation facility 402, and determines a flight route based on the position information of the unmanned aerial vehicle 202, the position information of the specific position, and the operating status of the wind power generation facility 402. As a result, the equipment inspection device 102 can perform inspection photography by bringing the unmanned aerial vehicle 202 close to the wind power generation facility 402 within a distance of several meters.

[0107] <C. Hardware Configuration> The position acquisition unit 11, condition acquisition unit 12, inspection unit 13, flight control unit 14, and equipment control unit 15 in the above-described equipment inspection devices 101, 102 are realized by a processing circuit 91 shown in FIG. 31. That is, the processing circuit 91 includes the position acquisition unit 11, condition acquisition unit 12, inspection unit 13, flight control unit 14, and equipment control unit 15 (hereinafter referred to as the position acquisition unit 11, etc.). The processing circuit 91 may be implemented by dedicated hardware, or may be implemented by a processor that executes a program stored in memory. Examples of the processor include a central processing unit, processing unit, arithmetic unit, microprocessor, microcomputer, DSP (Digital Signal Processor), etc.

[0108] When the processing circuitry 91 is dedicated hardware, the processing circuitry 91 may be, for example, a single circuit, a composite circuit, a programmed processor, a parallel programmed processor, an ASIC (Application Specific Integrated Circuit), an FPGA (Field-Programmable Gate Array), or a combination thereof. Each function of the position acquisition unit 11 and other units may be realized by multiple processing circuits 91, or the functions of each unit may be realized together by a single processing circuit.

[0109] When the processing circuit 91 is a processor, the functions of the position acquisition unit 11 and the like are realized by a combination of software, etc. (software, firmware, or software and firmware). The software, etc. is written as a program and stored in memory. As shown in FIG. 32 , the processor 92 applied to the processing circuit 91 realizes the functions of each unit by reading and executing a program stored in the memory 93. That is, the equipment inspection devices 101, 102 include a memory 93 for storing a program that, when executed by the processing circuit 91, results in the execution of the functions of the position acquisition unit 11 and the like. In other words, this program can be said to cause a computer to execute the procedure or method of the position acquisition unit 11 and the like. Here, the memory 93 may be, for example, a non-volatile or volatile semiconductor memory such as a RAM (Random Access Memory), a ROM (Read Only Memory), a flash memory, an EPROM (Erasable Programmable Read Only Memory), or an EEPROM (Electrically Erasable Programmable Read Only Memory), a HDD (Hard Disk Drive), a magnetic disk, a flexible disk, an optical disk, a compact disk, a mini disk, a DVD (Digital Versatile Disk) and its drive device, or any storage medium that will be used in the future.

[0110] The above describes a configuration in which each function of the position acquisition unit 11 and the like is realized either by hardware or software, etc. However, the present invention is not limited to this, and a configuration in which part of the position acquisition unit 11 and the like is realized by dedicated hardware and another part is realized by software, etc. For example, the function of the inspection unit 13 can be realized by a processing circuit as dedicated hardware, and the other functions can be realized by the processing circuit 91 as the processor 92 reading and executing programs stored in the memory 93.

[0111] As described above, the processing circuit can realize each of the above-described functions by hardware, software, or a combination of these.

[0112] It should be noted that the embodiments can be freely combined, and each embodiment can be modified or omitted as appropriate. The above description is an example in all respects. It is understood that countless variations not illustrated can be envisioned.

[0113] 11 Position acquisition unit, 12 Condition acquisition unit, 13 Inspection unit, 14 Flight control unit, 15 Equipment control unit, 21 GNSS, 22 Flight device, 23 Communication device, 24 Photography device, 25 First GNSS, 26 Support mechanism, 31 Communication unit, 32 Inspection planning unit, 33 Data collection unit, 34 Image analysis unit, 41 Communication unit, 42 Control unit, 43 Attitude control unit, 44 Blade, 45 Nacelle, 46 Tower, 47 Hub, 48 Second GNSS, 80 Sun, 81 Inspection route, 101, 102 Equipment inspection device, 201, 202, 202A Unmanned aerial vehicle, 301 Command center, 401, 402 Wind power generation equipment, 1001, 1002 Equipment inspection system.

Claims

1. An equipment inspection device comprising: a position acquisition unit that acquires position information of an unmanned aerial vehicle that flies and performs inspection photography while photographing inspection points of wind power generation equipment using an on-board photographing device; a condition acquisition unit that acquires the photographing conditions necessary for inspecting and photographing the wind power generation equipment; an inspection unit that determines the inspection state, which is the state of the wind power generation equipment to be taken during the inspection photography based on the photographing conditions, and determines the inspection route, which is the flight route of the unmanned aerial vehicle during the inspection photography; an equipment control unit that controls the wind power generation equipment to be in the inspection state; and a flight control unit that causes the unmanned aerial vehicle to fly the inspection route based on the position information while the wind power generation equipment is controlled in the inspection state, wherein the inspection unit causes the photographing device to photograph the wind power generation equipment while the unmanned aerial vehicle flies along the inspection route.

2. The equipment inspection device according to claim 1, wherein the photographing conditions include whether or not the wind power generation equipment is exposed to sunlight.

3. The equipment inspection device described in claim 2, wherein the inspection state includes a plurality of inspection states having different yaw angles of a nacelle of the wind power generation equipment, and the flight control unit flies the unmanned aerial vehicle along the inspection route based on the position information each time the state of the wind power generation equipment switches between the plurality of inspection states.

4. The equipment inspection device described in claim 1, wherein the photographing conditions include a solar orientation at the wind power generation equipment, and the inspection unit determines, based on the solar orientation, a yaw angle of a nacelle of the wind power generation equipment as the inspection state so that the inspection point of the wind power generation equipment faces the sun.

5. The equipment inspection device according to claim 1, wherein the photographing conditions include a wind direction at the wind power generation facility, and the inspection unit determines, as the inspection state, a yaw angle of a nacelle of the wind power generation facility so that an inspection point of the wind power generation facility faces a predetermined direction relative to the wind direction.

6. An equipment inspection device as described in any one of claims 1 to 5, wherein the photographing conditions include a wind speed at the wind power generation facility, and the inspection unit moves the inspection route away from the wind power generation facility as the wind speed increases.

7. An equipment inspection device as described in any one of claims 1 to 6, wherein the photographing conditions include an inspection location of the wind power generation equipment, and the inspection unit determines the posture of the wind power generation equipment as the inspection state based on the inspection location.

8. An equipment inspection device as described in any one of claims 1 to 7, wherein the photographing conditions include inspection contents of the wind power generation equipment, and when the inspection contents are inspection of a drive system of the wind power generation equipment, the inspection unit determines a state in which the drive system is driven as the inspection state.

9. An equipment inspection device as described in any one of claims 1 to 8, wherein the photographing condition information includes the inspection contents of the wind power generation equipment, and when the inspection contents are inspection of a sensor of the drive system of the wind power generation equipment, the inspection unit determines the state in which the drive system is driven as the inspection state, and acquires measurement information of the sensor of the drive system from the wind power generation equipment.

10. An equipment inspection device as described in any one of claims 1 to 9, wherein the position acquisition unit acquires position information of the unmanned aerial vehicle measured by a first GNSS with centimeter-order positioning accuracy installed on the unmanned aerial vehicle, and the inspection unit acquires from the wind power generation equipment position information of the specific position measured by a second GNSS with centimeter-order positioning accuracy installed at a specific position of the wind power generation equipment and the operating status of the wind power generation equipment, and determines the inspection route based on the position information of the unmanned aerial vehicle, the position information of the specific position, and the operating status of the wind power generation equipment.

11. The equipment inspection device described in claim 10, wherein the wind power generation equipment is installed offshore, and the inspection unit acquires a time series of position information of the second GNSS, predicts future pitch angle and roll angle of the tower of the wind power generation equipment based on the time series of position information of the second GNSS, and creates the inspection route based on the future pitch angle and roll angle of the tower, the position information of the unmanned aerial vehicle, the position information of the second GNSS, and the operating status of the wind power generation equipment.

12. The equipment inspection device described in claim 10, wherein the wind power generation equipment is installed offshore, the second GNSS is installed avoiding the center of rotation of a nacelle of the wind power generation equipment, and the inspection unit acquires a time series of position information of the second GNSS, predicts a future yaw angle of the nacelle based on the time series of position information of the second GNSS, and creates an inspection route for the unmanned aerial vehicle based on the future yaw angle of the nacelle, the position information of the unmanned aerial vehicle, the position information of the second GNSS, and the operating status of the wind power generation equipment.

13. An equipment inspection device as described in any one of claims 1 to 12, wherein the wind power generation facility is equipped with a power supply facility that supplies power to the unmanned aerial vehicle, and the flight control unit controls the unmanned aerial vehicle to receive power from the power supply facility before, during or after the inspection photography.

14. An equipment inspection device as described in any one of claims 1 to 13, wherein the equipment control unit is mounted on the unmanned aerial vehicle and controls the wind power generation equipment to the inspection state by directly communicating with the wind power generation equipment.

15. An equipment inspection device as described in any one of claims 1 to 14, wherein the inspection unit is mounted on the unmanned aerial vehicle, communicates directly with the wind power generation equipment, and transmits images captured by the imaging device to a ground command center via the wind power generation equipment.

16. An equipment inspection device as described in any one of claims 1 to 15, wherein the unmanned aerial vehicle flies from a departure point to the wind power generation facility, and then performs the inspection photography along the inspection route, and the inspection unit acquires future weather information and controls the departure time of the unmanned aerial vehicle from the departure point based on the future weather information and the time required for the unmanned aerial vehicle to travel from the departure point to the wind power generation facility.

17. An equipment inspection device as described in any one of claims 1 to 16, wherein the inspection unit acquires future weather information during the inspection photography, and stops the inspection photography by the unmanned aerial vehicle based on a comparison between the current weather information and the future weather information.

18. An equipment inspection device as described in any one of claims 1 to 17, wherein the inspection unit communicates with a monitoring unmanned aerial vehicle flying in a location where it can photograph the unmanned aerial vehicle during the inspection and photography, and obtains footage of the unmanned aerial vehicle captured by the monitoring unmanned aerial vehicle as evidence footage.

19. An equipment inspection device as described in any one of claims 1 to 18, wherein the unmanned aerial vehicle is equipped with a support mechanism that performs a support process of wiping the surface of the wind power generation equipment or detecting unevenness on the surface of the wind power generation equipment using a contact sensor, and the inspection unit causes the support mechanism to perform the support process on areas of the wind power generation equipment suspected of being damaged.

20. An equipment inspection method comprising: acquiring position information of an unmanned aerial vehicle that flies and performs inspection photography while photographing inspection points of a wind power generation equipment with an on-board camera; acquiring photography conditions necessary for inspecting and photographing the wind power generation equipment based on the photography conditions; determining an inspection state, which is the state of the wind power generation equipment to be taken during the inspection photography, and determining an inspection route, which is the flight route of the unmanned aerial vehicle during the inspection photography; controlling the wind power generation equipment to the inspection state; with the wind power generation equipment controlled to the inspection state, causing the unmanned aerial vehicle to fly the inspection route based on the position information; and having the camera photograph the wind power generation equipment while the unmanned aerial vehicle is flying along the inspection route.

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