JP2009191807A - Flying object collision avoiding system, and control method and computer program for the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a flying object collision avoiding system for efficiently reducing bird strikes in a wind power generator. <P>SOLUTION: This system comprises a wind power generator, which comprises a tower stood on the ground, a nacelle fixed to the tower and a plurality of blades rotatably fixed to the nacelle through hubs, an obstacle search device capable of detecting a flying object in the periphery of the wind power generator, and a blade angle control means for controlling angle change of the blades including a rotation stop position. The obstacle search device comprises a dome mirror and continuously searches flying objects by photographing images reflected by the dome mirror. When a flying object is detected, the blade angle control means controls the blades so as to be changed to the rotation stop position. This system is structured of a plurality of wind power generators and the obstacle search device in a smaller number than the wind power generators. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a technique for avoiding a situation in which a flying object collides with a blade when there is a flying object (mainly birds) approaching the wind power generator, and a technique related thereto.

In recent years, wind power generators have become larger in order to improve the output per unit. A typical large wind power generator is installed in a tower about 30 to 80 meters in height, and the blade of such a wind power generator is 20 to 50 meters, so the highest level reaches 130 meters from the ground. .
Such a height may reach the flying height of birds (such as raptors) that inhabit the vicinity of the place where the wind power generator is installed, or the height of cruise flight of migratory birds. And it is difficult for the flying birds to see the blade rotating at high speed, or an accident (bird strike) occurs that hits the blade and ends its life.

  As a technique for preventing a bird strike or a collision accident of a flying object, there is a technique disclosed in Patent Document 1.

JP 2006-125266 A

  As shown in FIG. 5, the wind power generator disclosed in Patent Document 1 includes an obstacle search device that can detect a flying object in front of the windward and a blade that controls the angle change of the blade including the rotation stop position. Angle control means. When it is determined that the flying object is approaching, the blade angle control means changes the blade to the rotation stop position.

When adopting a device for confirming the presence of flying objects based on imaging and image analysis for the obstacle search device of the wind power generator disclosed in Patent Document 1, it relies on image capture by natural light. Birds have a high flight speed (about 20 meters / second), so it may not be possible to search for obstacles at dusk or cloudy weather. If an irradiation apparatus that irradiates laser light is employed, the equipment cost and the operation cost will increase enormously.
Moreover, although the said obstacle search apparatus is supposed to catch the flying object in the windward front, there may be a case where only forward is not enough. A large number of camera modules (C-MOS sensors, etc.) are required to cover a wide area as a region for catching flying objects. In this case, the control-related system becomes large and maintenance becomes complicated.
Further, when a large number of wind power generators are installed like a wind farm, an area to be explored is widened, and more and more camera modules are required.

The problem to be solved by the present invention is to provide a technology capable of efficiently covering a wide area while improving exploration performance in a wind turbine generator capable of reducing blade damage and bird strike caused by flying objects. is there.
An object of the invention described in claims 1 to 4 is to provide a flying object collision avoidance system capable of reducing blade damage and bird strike caused by flying objects.

Another object of the present invention is to provide a flying object collision avoidance control process capable of reducing blade damage and bird strike caused by flying objects.
Another object of the present invention is to provide a flying object collision avoidance control program capable of reducing blade damage and bird strike caused by flying objects.

(Claim 1)
According to a first aspect of the present invention, there is provided a wind turbine generator including a tower erected on the ground, a nacelle fixed to the tower, and a plurality of blades fixed to the nacelle via a hub so as to be rotatable. The present invention relates to a flying object collision avoidance system including an obstacle searching apparatus capable of detecting flying objects around the wind turbine generator and blade angle control means for controlling blade angle change including a rotation stop position.
The obstacle search device is provided with a dome mirror to continuously search for flying objects by capturing images reflected by the dome mirror, and when the flying object is detected, the blade angle control means The blade is controlled to change to the rotation stop position.

(Glossary)
The “flying object” includes an object flying in the wind in addition to a creature such as a bird.
The “obstacle search device” is a device that confirms the presence of flying objects based on imaging and image analysis. The wind turbine generator is directed to the windward in order to maximize the power generation efficiency, but the “obstacle search device” does not need to move in synchronization with the wind turbine generator.
The “dome mirror” is a mirror having a hemispherical curved surface as a mirror surface. 360 degree vision can be obtained on the extension of the vertex.

“Rotation stop position” refers to a position where the blade does not rotate even if it receives wind. Typically, it is a feathering position or a sufficient deceleration of the rotation speed, but assists the brake to stop the blade rotation. In the case of use, the case where the rotation of the blade is stopped with the brake as the main is also included. As a rotation deceleration control means, a pitch controller that changes the pitch angle of the entire blade, and a blade shape and a pitch angle that loses lift, are selected, and the blade tip changes its direction by 90 degrees when stopped to serve as a brake. There is a stall controller.
In addition to the feathering position, the wind power generator is often formed so that a position that reduces the rotational efficiency according to the strong wind can be selected. This is because, if the rotation is completely stopped, it takes time to restart the operation. However, in the case of sufficient deceleration, it is easy to restart the operation, so that the power generation loss can be reduced.

(Function)
The wind power generator according to the present invention generates power by receiving wind and rotating the blade. The obstacle search device continuously searches for flying objects by capturing images reflected by the dome mirror. Therefore, it is possible to capture a wide area as well as upwind.
When a flying object is detected by the search by the obstacle search device, the blade angle control means controls to change the blade to the rotation stop position. As a result, the rotation of the blade stops or slows down sufficiently.
If the blade is stopped or sufficiently slowed down, the flying bird is easy to see, so the possibility of avoiding it increases. Further, since many blades are formed in a thin shape fixed about three radially from the hub, even if the flying object is a simple object other than a bird, the probability of colliding with the blade can be reduced.

(Claim 2)
The invention according to claim 2 limits the flying object collision avoidance system according to claim 1,
In the plurality of wind turbine generators provided, the obstacle search device is configured with a smaller number than the wind turbine generator.

(Function)
A single wind power generator may be installed alone, but in many cases, a plurality of wind power generators are installed in one area to form a wind farm. In this case, all the wind turbine generators may be provided with obstacle search devices, and each may independently control the wind turbine generator, but the equipment cost will increase.
According to the invention of this claim, the obstacle search device is a single wind power generator, and when the obstacle search device detects a flying object, the blade angle control means rotates the blade. The change control to the stop position is output to all the wind power generators in charge. As a result, the equipment cost and the cost for its operation can be suppressed.
For example, if there are four wind generators in a row, installing an obstacle survey device between the first and second wind generators and between the third and fourth wind generators To do. Since the obstacle exploration device includes a dome mirror with a wide vision, it can be configured with a smaller number than the wind power generation device.

(Claim 3)
The invention according to claim 3 limits the flying object collision avoidance system according to claim 1 or claim 2.
That is, the obstacle exploration apparatus relates to a flying object collision avoidance system in which a monochrome C-MOS sensor is used.

(Glossary)
The reason why the “C-MOS sensor” is adopted is that it is easier to control the exposure time than the CCD element and is suitable for capturing images of birds having a high flight speed. In addition, facilities such as laser light irradiation are not required.
Also, it is more suitable than a CCD element when natural light is insufficient due to cloudy weather.
The reason for limiting it to “monochrome” is that it can extract about three times as much sensitivity as a color C-MOS sensor. For example, a monochrome C-MOS sensor that can capture still images at a high speed of 500 fps with low noise and dynamic range can be used for shooting at a shutter speed of about 30 fps in cloudy weather.

(Function)
Since the obstacle search device functions by imaging with a monochrome C-MOS sensor, it is suitable for capturing images of birds with high flight speed. In addition, it is possible to shoot when the natural light is weak, such as when it is cloudy or dusk.

(Claim 4)
The invention according to claim 4 limits the flying object collision avoidance system according to any one of claims 1 to 3.
That is, it has an arrival time calculation means for calculating the expected arrival time of the flying object detected by the obstacle exploration device, and the blade angle control means changes the blade angle to the rotation stop position before reaching the expected arrival time. It is characterized by controlling to.

(Glossary)
The “arrival time calculation means” is a means in which the obstacle exploration device continuously explores flying objects and predicts the arrival time of the flying objects from the speed and distance of the flying objects.
In other words, when the approach of the flying object is detected and the rotation is determined to be stopped, the blade angle control means secures the time required for changing the blade angle and stopping the rotation of the blade (for example, around 3 seconds). It is necessary to search for flying objects as far away as possible.

(Function)
The arrival time calculation means calculates the expected arrival time of the flying object detected by the obstacle search device. Then, the blade angle control means controls to change the blade angle to the rotation stop position before reaching the expected arrival time. As a result, it is possible to increase the probability of preventing blade breakage and bird strike due to flying objects.

(Claim 5)
According to a fifth aspect of the present invention, there is provided a wind turbine generator including a tower erected on the ground, a nacelle fixed to the tower, and a plurality of blades fixed to the nacelle via a hub so as to be rotatable. In a plurality of wind farms, there is an obstacle search device capable of detecting flying objects around the wind farm, and a flying object collision avoidance equipped with blade angle control means for controlling the blade angle change including the rotation stop position. The present invention relates to a system control method.
That is, an imaging procedure for capturing a dome mirror and an image reflected by the dome mirror, a flying object detection procedure for detecting a flying object by analyzing the image captured by the imaging procedure, and a flying object detection procedure. And a rotation stop procedure for controlling the blade to change to a rotation stop position when an object is detected.

(Claim 6)
The invention according to claim 6 limits the control method of the flying object collision avoidance system according to claim 5.
That is, in the plurality of wind turbine generators, the obstacle search device is configured with a smaller number than the wind turbine generator. And when the obstacle search device detects a flying object in the flying object detection procedure, the rotation stopping procedure controls the corresponding wind power generator to change the blade to the rotation stop position. It is characterized by that.

(Claim 7)
According to a seventh aspect of the present invention, there is provided a wind turbine generator comprising a tower erected on the ground, a nacelle fixed to the tower, and a plurality of blades fixed to the nacelle via a hub so as to be rotatable. In a plurality of wind farms, there is an obstacle search device capable of detecting flying objects around the wind farm, and a flying object collision avoidance equipped with blade angle control means for controlling the blade angle change including the rotation stop position. It relates to the system control program.
The control program includes an imaging procedure for capturing a dome mirror and an image reflected by the dome mirror, a flying object detection procedure for detecting a flying object by analyzing the image captured by the imaging procedure, and the flying object detection procedure. When a flying object is detected at, a computer program that causes a computer to execute a rotation stop procedure for controlling the blade to change to a rotation stop position.

(Claim 8)
The invention according to claim 8 limits the computer program according to claim 7.
That is, in the plurality of wind turbine generators, the obstacle search device is configured with a smaller number than the wind turbine generator. And when the obstacle search device detects a flying object in the flying object detection procedure, the rotation stopping procedure controls the corresponding wind power generator to change the blade to the rotation stop position. It is characterized by that.

The computer program according to claims 7 to 8 can be made into a chip and used as a blade control device of a wind turbine generator.
It can also be stored in a recording medium and provided. Here, the “recording medium” is a medium that can carry a program that cannot occupy space by itself, such as a flexible disk, a hard disk, a CD-R, an MO (magneto-optical disk), a DVD- R and the like.

According to the first to fourth aspects of the present invention, it is possible to provide a flying object collision avoidance system capable of reducing blade damage and bird strike caused by flying objects. According to the invention described in the sixth aspect, it is possible to provide a control process for avoiding a flying object collision that can reduce blade damage and bird strike caused by the flying object.
Further, according to the inventions described in claims 7 to 8, it is possible to provide a control program for avoiding flying object collision that can reduce blade damage and bird strike caused by flying objects.

Embodiments of the present invention will be described with reference to the drawings.
The drawings used here are FIGS. 1 to 5. FIG. 1 is a conceptual diagram showing the first embodiment, and FIG. 2 is an enlarged view of a main part thereof. FIG. 3 is a flowchart showing the control process. FIG. 4 is a graph showing wind speed and power generation amount. FIG. 5 is an image diagram of the emitted wave and the reflected wave when there is a flying object.

(First embodiment)
The first embodiment shown in FIG. 1 shows a flying object collision avoidance system in four wind power generators (A, B, C, D). Each wind power generator (A, B, C, D) includes a tower standing on the ground, a nacelle fixed to the tower, and a plurality of rotatably fixed to the nacelle via a hub. It has a blade. In addition, the two wind turbine generators (A, B) are provided with an obstacle search device that can detect flying objects around the wind turbine generator.
Since the obstacle exploration device is provided as a single unit for a plurality of wind power generators, the equipment cost and the cost for its operation can be suppressed.

  The obstacle exploration device is provided with a dome mirror and continuously explores flying objects by photographing an image reflected by the dome mirror. When a flying object is detected, the blade angle change including the rotation stop position of each wind power generator (A, B, C, D) is controlled. This control is performed by the blade angle control means, which is not shown. Obstacle exploration device is one in plural wind power generators, and when the obstacle exploration device detects a flying object, the blade angle control means is in charge of changing control to the blade rotation stop position. Output to all of the wind power generators.

As shown in detail in FIG. 2, the obstacle exploration apparatus includes a dome mirror, a digital camera (monochrome C-MOS sensor) that captures an image reflected by the dome mirror, and a camera moving body shown in FIG. Prepare.
The dome mirror is a mirror having a hemispherical curved surface as a mirror surface, and 360 degree vision can be obtained on extension of the apex. However, it may be difficult to calculate the exact distance when there is a flying object. In such a case, processing such as distance calculation is performed by interpolating data with images obtained by other obstacle exploration devices. To do.
Moreover, it is good also as acquiring the data regarding the flight route of a bird, accumulate | stored in the bird flight route database, and using the data. Specifically, for example, it is determined whether or not the observer is a bird with moving image data regarding a flying object, and if the flying object is a bird, it is stored in the bird flight route database as bird flight data. is there. When it is difficult to calculate an accurate distance when there is a flying object, the bird flight route database is accessed, and a calculation such as predicting a bird's flight is executed, and used for distance calculation.

  The reason why the monochrome C-MOS is used is that it is suitable for photographing when the natural light is insufficient due to cloudy weather or the like than the CCD, and about 3 times higher sensitivity than the color C-MOS sensor can be obtained. For example, a monochrome C-MOS sensor that can capture still images at a high speed of 500 fps with low noise and dynamic range can be used for shooting at a shutter speed of about 30 fps in cloudy weather.

  Although not shown, an arrival time calculating means for calculating the expected arrival time of the flying object detected by the obstacle searching device is provided. The blade angle control means described above controls to change the blade angle to the rotation stop position before reaching the expected arrival time. When the approach of the flying object is detected and the rotation is determined to be stopped, the blade angle control means secures a time (for example, around 3 seconds) necessary for changing the blade angle to stop the rotation of the blade.

This will be described in more detail with reference to FIG. FIG. 3 is a flowchart showing an example of control.
The wind power generator generates electricity by receiving wind and rotating the blades. Here, if the obstacle search device does not detect a flying object on the windward, the operation is continued.
Here, it is assumed that a flying object is detected. Then, by continuously searching for flying objects, data relating to flying objects is stored for a predetermined time or compared with the immediately preceding data. When the flying object approaches, the predicted arrival time of the flying object is calculated from the flight speed V and the distance X, and the blade angle control means controls the blade to change to the rotation stop position (feathering). To do. Then, the rotation of the blade is stopped before the predicted arrival time of the flying object.
The control program as described above is incorporated in the blade control device.

  If the blade is stopped, it is easy to see the flying bird, so the possibility of avoiding it increases. In addition, since many blades have a thin shape that is fixed about three radially from the hub, even if the flying object is a simple object other than a bird, the probability of colliding with the blade can be reduced. Since the flying object collision avoidance system determines whether or not it has approached, once it has been detected that the flying object has not been approached, there is little possibility of a collision and it is not necessary to stop power generation wastefully.

Obstacle exploration device is not only a device that confirms the presence of flying objects based on imaging and image analysis, but also a device that confirms the presence of flying objects by oscillating sound waves or electromagnetic waves and capturing the reflected waves, or A heat sensing device can also be used in combination.
If a heat sensing device is used, only flying objects with higher temperatures than the surroundings, such as birds and other creatures, can be detected. There is an advantage that can be accurately detected.

  FIG. 4 shows the relationship between the wind speed and the power generation amount. The blade is adjusted so that it can be operated at the rated wind speed. When the wind speed exceeds a predetermined level (cutout wind speed), power generation is stopped by feathering. In the present embodiment, the change to feathering is executed even when a flying object approaches.

As described above, since the flight speed of birds is as fast as about 20 meters / second, the CCD camera may not be able to search for obstacles at dusk or cloudy weather. For example, obstacle search is possible without using a laser beam irradiation device.
In addition, since the obstacle search apparatus used in this embodiment uses a dome mirror, the area for capturing flying objects is broadened and reasonably covered.
Furthermore, although many wind power generators are installed, it is not necessary to provide an obstacle search device in each wind power generator.

The obstacle search apparatus using not only imaging and image analysis but also reflection of ultrasonic waves will be described in more detail with reference to FIG.
The obstacle exploration device in the figure transmits ultrasonic waves and receives reflected waves if there are flying objects. If the launch wave f1, the flying speed V of flying objects (birds), and the reflected wave f2,
The equation V = (1-f2 / f1) × sound speed holds, and the distance X from the return time of f2 to the flying object can be measured.

Note that the obstacle exploration device emits to the windward because the ultrasonic emission angle is limited. For this reason, it is built in the nacelle that faces the windward in conjunction with the anemometer.
When the measured value of the wind speed is greater than or equal to a predetermined value by measuring the anemometer, it is possible to prevent the blade from being damaged due to a gust by controlling the blade angle and the like.

  The present invention can be used in the manufacturing industry of wind power generators and flying object collision avoidance devices, the maintenance business of wind power generators or flying object collision avoidance devices, the software development industry for flying object collision avoidance systems, etc. .

It is a conceptual diagram which shows 1st embodiment. It is an enlarged view of the principal part. It is a flowchart which shows a control process. It is a graph which shows a wind speed and electric power generation amount. It is an image figure of the emitted wave and reflected wave in the case of a flying object.

Claims (8)

A wind turbine generator comprising a tower erected on the ground, a nacelle fixed to the tower, and a plurality of blades rotatably fixed to the nacelle via a hub. A flying object collision avoidance system comprising an obstacle exploration device capable of detecting flying objects and blade angle control means for controlling blade angle change including a rotation stop position,
The obstacle exploration device has a dome mirror and continuously explores flying objects by photographing an image reflected by the dome mirror.
A flying object collision avoidance system in which when the flying object is detected, the blade angle control means controls to change the blade to the rotation stop position. In the wind power generator provided with a plurality,
2. The flying object collision avoidance system according to claim 1, wherein the obstacle search device is configured with a smaller number than a wind power generation device.   The flying object collision avoidance system according to claim 1, wherein a monochrome C-MOS sensor is used for the obstacle search device. It has an arrival time calculation means for calculating the expected arrival time of the flying object detected by the obstacle exploration device,
The flying object collision avoidance system according to any one of claims 1 to 3, wherein the blade angle control means controls to change the angle of the blade to the rotation stop position before reaching the expected arrival time. In a wind farm comprising a plurality of wind power generators comprising a tower erected on the ground, a nacelle fixed to the tower, and a plurality of blades fixed to the nacelle via a hub so as to be rotatable. A control method for a projectile collision avoidance system comprising an obstacle search device capable of detecting a projectile around a wind farm and a blade angle control means for controlling a blade angle change including a rotation stop position,
An imaging procedure for shooting a dome mirror and an image reflected by the dome mirror;
A flying object detection procedure for detecting a flying object by analyzing the image captured by the imaging procedure,
A method for controlling a flying object collision avoidance system, comprising: a rotation stopping procedure for controlling the blade to change to a rotation stopping position when a flying object is detected by the flying object detection procedure. In the wind power generator provided with a plurality, the obstacle exploration device is configured with a smaller number than the wind power generator,
When the obstacle exploration device detects a flying object in the flying object detection procedure, the rotation stopping procedure is to control the corresponding wind power generator to change the blade to the rotation stop position. The method for controlling the flying object collision avoidance system according to claim 5. In a wind farm comprising a plurality of wind power generators comprising a tower erected on the ground, a nacelle fixed to the tower, and a plurality of blades fixed to the nacelle via a hub so as to be rotatable. A control program for a projectile collision avoidance system comprising an obstacle search device capable of detecting a projectile around a wind farm and a blade angle control means for controlling a change in blade angle including a rotation stop position,
The control program includes an imaging procedure for capturing a dome mirror and an image reflected by the dome mirror,
A flying object detection procedure for detecting a flying object by analyzing the image captured by the imaging procedure,
A computer program for causing a computer to execute a rotation stopping procedure for controlling the blade to change to a rotation stopping position when a flying object is detected by the flying object detection procedure. In the plurality of wind power generators provided, the obstacle exploration device is configured with a smaller number than the wind power generator,
When the obstacle exploration device detects a flying object in the flying object detection procedure, the rotation stopping procedure is to control the corresponding wind power generator to change the blade to the rotation stop position. The computer program according to claim 7.

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