JP2014025428A - Wind-power generation apparatus with lightning protection system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wind-power generation apparatus with a relatively simple lightning protection system that makes a lightning strike current upon lightning flow to the ground surface without breaking a blade nor entering a support column side including a nacelle.SOLUTION: A wind-power generation apparatus 1 includes a support column 3 provided fixedly on the ground, a nacelle 4 which has at least a rotor of a power generator inside and is mounted on a top of the support column, blades 2a, 2b, and 2c for rotating the rotor provided in the nacelle 4 by wind force, and a hub 5 which connects the blades 2a, 2b, and 2c and the rotary shaft of the rotor. Further, while a metal material layer 6 and a nonlinear resistance material layer 7 are formed alternately on surfaces of the blades 2a, 2b, and 2c partially in contact to each other and the metal material layer 6 is arranged at tip parts of the blades 2a, 2b, and 2c, a nonlinear resistance material layer 7 is arranged at a part adjoining the hub 5.

Description

  Embodiments of the present invention relate to a wind turbine generator having a lightning protection system for reducing the effects of lightning strikes.

  Various types of wind turbines are used in the wind turbine generator, but a blade type wind turbine is known as a wind turbine having a large capacity and good power generation efficiency.

FIG. 4 shows a schematic configuration of a wind turbine generator using a conventional blade type windmill.
In this wind power generator 50, a nacelle 4 containing a generator rotor, a control system device, electronic equipment, and the like is provided at the top of the column 3, and the generator rotor in the nacelle 4 is connected via a hub 5. The blade 2 (blade) outside the nacelle is connected. In such a windmill, the blade 2 receives wind to rotate the hub 5, and the rotation is transmitted to the rotor of the generator to generate electricity.

  In the wind power generator 50, when a wind turbine for large-scale power generation is used, the height of the support column 3 is about 50 meters, and the length of the blade 2 is very large at several tens of meters. Because of this size, it is not just a generator, it also creates landmark value and can be a tourist destination.

  As the blade 2, wood has been used so far when the output of the wind power generator 50 is small, and the inside is an air layer for weight reduction. However, in recent years, fiber reinforced plastics (FRP: Fiber Reinforced Plastics) have come to be used in order to increase the area that is exposed to wind for a long time as wind power generators with high output are developed. By using FRP for the blade 2, it is possible to manufacture a strong wind power generator 50 that exceeds 250 kW even if it is light and strong.

  As described above, the blade 2 is very large, is located at a high position, and is often installed on a vast land that is easily affected by wind. For this reason, there are many damages caused by lightning strikes, for example, damage to the blade 2 or the like due to lightning strikes, or failure of the control system device due to lightning strikes, which is said to account for a quarter of the failure factors.

  The damage to the blade 2 is caused by the fact that lightning penetrates the blade 2 and a large current flows through the blade 2, so that the air layer in the inside expands with the amount of heat generated by the lightning strike current and generates high pressure in a short time. To do. In addition, since the wind power generator 50 is large, not only the cost of the blade 2 alone is expensive, but also the replacement of the blade 2 requires the use of a large crane, and the repair cost is enormous.

  In order to prevent the blade 2 from being damaged by lightning, it is considered to install a lightning rod in the portion of the nacelle 4 of the wind power generation device 50. Even if the blade 2 can be prevented from being destroyed by lightning, the nacelle 4 Electronic components such as the control system inside may be destroyed and the function of the device may be lost.

  As another method for preventing the blade 2 from being damaged by lightning, a method of applying a conductive particle layer to a structure has been proposed. In this method, the lightning strike current during lightning strikes to the ground without destroying the structure by forming a conductive lightning protection auxiliary coating on the surface of the blade 2, hub 5, nacelle 4 and column 3 in FIG. It is a method of flowing.

  However, in the method of applying a lightning protection auxiliary coating film as described above and causing the lightning current to flow to the ground, there is a risk that the lightning current will continue to flow through only one path, and even the lightning protection coating film and the blade 2 body may be destroyed. was there.

Japanese Patent No. 3948469 Japanese Patent No. 4828177

  In view of such a problem, the embodiment of the present invention is relatively simple in that a lightning strike current at the time of a lightning strike can flow to the ground without destroying the blade and without entering the column side including the nacelle. An object of the present invention is to provide a wind turbine generator equipped with a lightning protection system.

  In order to achieve the above-described object, a wind turbine generator having a lightning protection system according to an embodiment of the present invention includes a support column fixed to the ground and at least a generator rotor, and is mounted on the top of the support column. A wind turbine generator comprising: a nacelle installed; a blade for rotating the rotor provided in the nacelle by wind power; and a hub connecting the blade and a rotating shaft of the rotor. The metal material layer and the non-linear resistance material layer are alternately formed on the surface of the blade, and the metal material layer is disposed at the tip portion of the blade while the blade is adjacent to the hub. A non-linear resistance material layer is disposed on the surface.

It is a front view which shows schematic structure of the wind power generator provided with the lightning protection system of one Embodiment of this invention. It is a side view of the wind power generator of FIG. It is an enlarged view of the blade part of the wind power generator of FIG. It is a side view which shows schematic structure of the conventional wind power generator.

Embodiments of the present invention will be specifically described below with reference to the drawings.
(Constitution)
As shown in FIGS. 1 to 3, the wind turbine generator 1 of the present embodiment includes a support column 3 fixed to the ground, a generator rotor, a control system device, an electronic device, and the like. A nacelle 4 placed on the top of the blade, blades (blades) 2a, 2b, 2c for rotating the rotor of the generator provided in the nacelle 4 by wind power, blades 2a, 2b, 2c and rotation And a hub 5 for connecting a shaft (not shown). Further, as shown in FIG. 2, the hub 5 is connected to the ground by a lead wire 8 and serves as a lightning current path as will be described later.

(Blade 2a, 2b, 2c)
In the wind power generator 1, the blades 2a, 2b, and 2c rotate by receiving wind, and the rotation is transmitted to the rotor of the generator via the hub 5 or the like to generate electric power. These blades 2a, 2b, 2c are preferably formed of FRP.

  As shown in FIG. 3, metal material layers 6a, 6b, 6c and nonlinear resistance material layers 7a, 7b, 7c are alternately formed on the surface of the blade 2. Here, the nonlinear resistance material layers 7a, 7b, and 7c can be formed using ZnO. In the blade 2, a metal material layer 6 a is formed at the tip portion, and a nonlinear resistance material layer 7 c is formed at a portion adjacent to the hub 5. Further, the nonlinear resistance material layer 7c and the hub 5 are electrically connected at a portion not shown.

  The metal material layer 6 and the non-linear resistance material layer 7 are preferably brought into contact with each other at a boundary line. Moreover, it is preferable that the number of the metal material layers 6 and the nonlinear resistance material layers 7 is the same.

  The width of the metal material layer 6 is desirably 10 mm to 1000 mm. If it is less than 10 mm, the effect of dispersing the lightning current may not be sufficiently exhibited, and if it exceeds 1000 mm, the range of radio interference may be widened.

  The width of the nonlinear resistance material layer 7 is desirably 10 mm or more. If the thickness is less than 10 mm, the lightning current may not discharge through the non-linear resistance material layer 7 and may be discharged along the creepage surface, and there is a risk that the non-linear resistance material layer 7 is destroyed and loses its function. Further, the thickness of the nonlinear resistance material layer 7 is desirably 1 mm or more. If it is less than 1 mm, there is a risk that the non-linear resistance material layer 7 will break down due to the lightning current and the blade 2 will be broken.

(Function)
In the wind turbine generator 1 having the above configuration, for example, when a lightning strike occurs at the tip of the blade 2, a voltage is applied to the nonlinear resistance material layer 7a, and a lightning current flows. Next, in the metal material layer 6b, the entire potential of the metal is the same, so that a voltage is uniformly applied to the nonlinear resistance material layer 7b.

  In general, between metal flat plates, an electric field concentrates on minute protrusions existing on the metal flat plates, and a discharge current flows from the protrusions as a starting point. However, according to the above configuration, since the non-linear resistance material layer 7 is disposed between the metal material layers 6 disposed in parallel, the electric field is alleviated even if there are minute protrusions. For this reason, the electric field applied between the metal material layers 6 is close to an equal electric field, and there is a high possibility that a current flows uniformly through the nonlinear resistance material layer 7.

  Therefore, in the wind turbine generator 1, until the lightning current reaches the hub 5 from the tip of the blade 2, the metal material layer 6 and the non-linear resistance material layer 7 flow uniformly, and further to the ground via the lead wire 8. A lightning current can flow.

(effect)
Therefore, according to the wind turbine generator 1, the blade 2 is not destroyed by the lightning current when a lightning strikes, and the lightning current is allowed to flow to the ground without entering the column side including the nacelle 4 with a relatively simple configuration. be able to.

(Other embodiments)
The present invention also includes other embodiments as follows.
(1) The blade 2 is composed of three blades 2a, 2b, and 2c as shown in FIG. 1, but may have one or two blades, or may have four or more blades. .

(2) Although the number of the metal material layers 6 and the nonlinear resistance material layers 7 is three in FIG. 3, the tip portion of the blade 2 is the metal material layer 6 and the portion adjacent to the hub 5 is the nonlinear resistance material layer 7. 3 and the number and shape of the metal material layers 6 and the nonlinear resistance material layers 7 are shown in FIG. It is not restricted to a thing, It can change suitably.

(3) Although the embodiment of the present invention has been described above, this embodiment is presented as an example and is not intended to limit the scope of the invention. This embodiment can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the spirit of the invention. This embodiment and its modifications are included in the scope of the present invention and the gist thereof, and are also included in the invention described in the claims and the equivalent scope thereof.

DESCRIPTION OF SYMBOLS 1 ... Wind power generator 2 ... Blade 2a, 2b, 2c ... Blade 3 ... Strut 4 ... Nacelle 5 ... Hub 6 ... Metal material layer 6a, 6b, 6c ... Metal material layer 7 ... Nonlinear resistance material layer 7a, 7b, 7c ... Nonlinear resistance material layer 8 ... Lead wire

Claims (4)

A support column fixed to the ground, a nacelle at least including a generator rotor and mounted on the top of the support column, and a blade for rotating the rotor provided in the nacelle by wind power And a hub for connecting the blade and the rotating shaft of the rotor,
A metal material layer and a non-linear resistance material layer are alternately formed on the surface of the blade while being in contact with each other, and the metal material layer is disposed at a tip portion of the blade while adjacent to the hub of the blade. A wind power generator equipped with a lightning protection system, wherein a non-linear resistance material layer is disposed on the portion to be operated.   The wind power generator equipped with the lightning protection system according to claim 1, wherein the thickness of the nonlinear resistance material layer is 1 mm or more.   The wind power generator equipped with the lightning protection system according to claim 1, wherein a width of the nonlinear resistance material layer is 10 mm or more.   The wind power generator equipped with the lightning protection system according to any one of claims 1 to 3, wherein a width of the metal material layer is 10 mm to 1000 mm.

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