JPH03271566A - Wind mill blade - Google Patents

Abstract

PURPOSE:To obtain a wind mill blade, prevented from easily causing a trouble and also easily manufactured inexpensively with no complicated device of variable pitch mechanism or the like required, by forming the blade, made into a laminated structure, partly into the laminated structure having at least one layer of asymmetrical orientation angle. CONSTITUTION:A wind mill blade 2, requiring strength, rigidity and lightness against wind force, is formed of a plurality of layers of fiber reinforced compound material. Normally the more required are the rigidity and the strength, the larger a number of layers of this fiber reinforced compound material is increased. Accordingly, normally the number of laminated layers in a base part 2a is increased larger than that in a point end part 2b, of the wind mill blade 2. A fiber orientation angle of the layer is given symmetrical orientation of + or -theta with theta=0 as the main orientation in order to increase strength and rigidity and further to ensure the symmetry of deformation. Here the point end part 2b is partly molded by laminating the layer of asymmetrical orientation. That is, of the plurality of layers of fiber reinforced compound material 2c, a single or plurality of layers of fiber reinforced compound material 2c on a surface part are formed by laminating the layer so as to provide the orientation angle thetaat 10 deg. through 50 deg. and further the asymmetrical orientation.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a wind turbine blade used in a wind power generator or the like.

[Prior Art] Conventionally, in order to improve the power generation efficiency of a wind power generation device using a wind turbine, a variable pitch wind turbine that changes the pitch of the wind turbine blades according to the wind speed is known.

[Problem to be solved by the invention] However, conventional wind turbine blades of this type change the pitch of the blades depending on the wind speed, which makes the equipment configuration complicated, requires a control device, and is prone to failure. , and it is expensive.

The problems of the present invention are to provide a wind turbine blade that automatically changes the pitch angle according to the wind speed, eliminates the need for complicated equipment such as a variable pitch mechanism, prevents the wind turbine from malfunctioning, and that is inexpensive and easy to manufacture. Our goal is to provide the following.

[Means for Solving the Problems] The present invention provides a wind turbine blade formed by laminating multiple layers of fiber-reinforced composite materials, in which a part of the blade having a laminated structure has at least one layer with an asymmetric orientation angle. A special vehicle blade characterized in that it has a laminated structure, and an asymmetrical orientation angle of the at least one layer of fiber reinforced composite material of 10 degrees to 5 degrees.
By creating a windmill blade characterized by a temperature of 0 degrees.

By generating torsional deformation in the wind turbine blades in proportion to the bending deformation caused by wind power, it is possible to perform control equivalent to partially variable pitch control of the wind turbine blades while keeping the wind turbine blades mechanically fixed. This is what I did.

[Example code] Next, embodiments of the present invention will be described in detail based on the drawings.

FIG. 1 shows a rotor portion of a wind turbine, and in the figure, reference numeral 1 indicates a hub of the wind turbine.

A plurality of wind turbine blades 2 are fixed to the hub 1 at predetermined intervals, and the wind force acting on the wind turbine blades 2 is transmitted to the hub as rotational force.

Power is generated by driving a generator via a power transmission system (not shown).

The wind turbine blade 2 is required to have sufficient strength and rigidity to withstand wind force, and to be lightweight, so it is made of a multi-layered fiber reinforced composite material. The number of layers of this fiber-reinforced composite material usually increases as the rigidity and strength of the wind turbine blade 2 is required.

Therefore, the base part 2g (for example, area CL-1 in FIG. 2) of the 1 normal wind turbine blade 2 is
The number of laminated layers is larger than in the area g in the figure). In addition, the fiber orientation angle θ increases the strength and rigidity of the blade, and in order to further ensure the symmetry of deformation, symmetrical orientations of ±θ (for example, +45°, -45') are added to the main orientation of θ-0. It is formed by The wind turbine blade of the present invention is characterized in that the tip part (2b) is laminated in an asymmetrical orientation with respect to such a basic laminated structure.

That is, as shown in FIG. 3, multiple layers (for example, 3 to 6 layers)
One or more layers of the fiber reinforced composite material 2c on the surface of the fiber reinforced composite material 2c have an orientation angle θ of 10 degrees to 5 degrees.
They are formed by stacking them so that they are oriented at 0 degrees and asymmetrically.

The number n of laminated layers, orientation angle θ, and asymmetric orientation area of the asymmetrically oriented portion are appropriately designed according to the required characteristics of the blade 2. The asymmetrical orientation angle θ is preferably selected in the range of 10 degrees to 50 degrees because the effect (effect) reaches its maximum when the orientation angle θ is 30 degrees and is extremely reduced (becomes small) when the orientation angle θ is less than 10 degrees or 51 degrees or more.

Next, the present invention will be explained in detail.

As shown in Figure 1, the cross section of the wind turbine blade 2 is in the rotational direction (
In order to increase the efficiency of the wind turbine, the tip must be made as small as shown in Figure 4, in order to increase the efficiency of the wind turbine. Therefore, the wind turbine blade 2 has a helix angle. This curved angle at the tip is generally called the pitch angle, and the power generation characteristics change depending on this pitch angle.

Conventionally, a method called in-shell variable pitch control maintains the generator's capacity limit by mechanically changing the tucking angle of all or part of the wind turbine blades in strong wind regions where the rotor generates more power than its generating capacity. This makes it possible to sustain power generation even in areas with strong winds.

However, in this case, the structure and control of the rotor portion become extremely complicated. - In the case of the wind turbine blade 2 of the invention, due to the characteristics of the structure having an asymmetrically maintained orientation, torsional deformation occurs in proportion to the bending moment on the wind turbine blade 2 caused by the drag action of Ml, as shown in Figure 4. The pitch angle will decrease by Δ. As shown in FIG. 5, the pitch angle increases with the strength of the pitch angle change, and this effect can suppress (stall) the power generation efficiency in a region with strong winds.

Moreover, it also has the effect of improving power generation efficiency in the medium wind speed region.
Although it is a fixed wing, it is possible to achieve the same performance as a variable pitch wing. Note that 1 power generation efficiency characteristics are determined by the asymmetric orientation angle θ, the number n of stacked layers of the asymmetric orientation part, and the asymmetric orientation area g.
You can design it freely.

Figure 6 shows the wind speeds of wind turbine generators using wind turbines with a power generation capacity of 200 kW, one with conventional fixed pitch wind turbine blades, one with wind turbine blades 2 of the present invention, and one with wind turbine blades 2 of the present invention. This shows the relationship between the amount of power generated and the amount of power generated.

In the same figure, the solid line E shows the relationship between the wind speed and the amount of power generated in a wind power generator using a wind turbine having seven present invention and the dashed-dot line F using a conventional wind turbine having fixed wind turbine blades 2.

The experimental example shown by this solid line E is at a stall wind speed of V-50MP.
Δy-10 degrees at H, L-10m+ (173rn.

The rotational speed of the wind turbine is Ω-6ORPM.

As can be seen from this example, the wind turbine blade 2 of the present invention deforms to suppress the rotation of the wind turbine when the wind speed V approaches a set value (50 MPH), so it can be used even in a high wind speed range.

On the other hand, if the same conditions were used to generate electricity using a conventional wind turbine with fixed pitch wind turbine blades.

When the wind speed V reaches 50 MPM, the set power generation amount (ν to 200) is exceeded, as shown by the dashed line F in Figure 6, and one generator becomes overloaded, so one power generation has to be stopped. .

It can be seen that the power generation efficiency of the wind power generation device using the wind turbine having the wind turbine blades 2 of the present invention is much higher in the high wind speed region than the power generation efficiency of the wind power generation device using the wind turbine having the conventional fixed pitch wind turbine blades.

[Effects of the Invention] According to the present invention, since the pitch angle automatically changes according to the wind speed, a complicated device such as a variable pitch mechanism is not required, and the wind turbine is less likely to break down and is inexpensive to manufacture. It's easy.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing the main parts of a wind turbine having wind turbine blades according to the present invention, FIG. 2 is a front view showing the same wind turbine blade, and FIG. 3 is a diagram for explaining the configuration of the tip of the same wind turbine blade. FIG. 4 is a diagram for explaining the angle of engagement between the wind turbine blade of the present invention and a conventional fixed pitch wind turbine blade, FIG. The figure is a diagram showing the relationship between wind speed and power generation amount in a wind power generation device using a wind turbine having wind turbine blades of the present invention and a wind power generation device using a wind turbine having conventional fixed pitch wind turbine blades. 1... Hub, 2... Wind turbine blade, 2c... Fiber reinforced composite material. Figure 1 Figure 2 -X Figure 3

Claims (2)

[Claims] (1) A wind turbine blade formed by laminating multiple layers of fiber-reinforced composite material, characterized in that a part of the laminated blade has a laminated structure having at least one layer with an asymmetric orientation angle. blade. (2) The wind turbine blade according to claim 1, wherein the asymmetric orientation angle is between 10 degrees and 50 degrees.