JP2022042027A - Wind turbine facility and wind turbine blade - Google Patents

Abstract

To provide wind turbine blades and a wind turbine facility capable of easily obtaining activation torque at the time when a wind turbine is stationary or rotating at low speed, and also capable of suppressing air resistance of blades at the time when the wind turbine is rotating at high speed to obtain high energy efficiency.SOLUTION: A wind turbine facility is configured so that a rotational shaft 1 is horizontal and intersects a wind direction, where blades 2 rotate from upwind to leeward above the rotational shaft, and comprises a lid 4 that can freely open and close from a support shaft on a surface near the rotation shaft of the blades to a stopper 5 with its rear side in a rotation traveling direction directed to the rotation shaft side. When the rotation speed of a wind turbine is low, the lid of the blade above the rotation shaft opens to become a wind receiving surface and generate activation torque, and the lid of the blade below the rotation shaft closes to reduce the air resistance of rotation. When the rotation speed is high, the lids are closed by centrifugal force and rotation traveling wind to suppress the air resistance.SELECTED DRAWING: Figure 5

Description

The present invention relates to a blade for a wind turbine and a wind turbine including the blade.

Examples of the wind turbine that receives power from the wind include a horizontal axis wind turbine represented by a propeller type wind turbine and a vertical axis wind turbine such as a Darius type wind turbine and a gyromill wind turbine. Each has a rotating shaft and one or more blades provided around the rotating shaft.

The types of blades of a wind turbine are classified into a lift type that rotates by using the lift generated by the blade by the wind and a drag type that rotates by using the force that the wind pushes the blade.

Vertical-axis wind turbines that utilize the lift generated by the blades are difficult to obtain rotational torque and have poor startability. On the other hand, a vertical-axis wind turbine that utilizes drag on the blades can be activated even in a weak wind, but the rotation of the blades can only increase to the same level as the wind speed, resulting in poor energy efficiency. Therefore, the lift type wind turbine is often used in combination with the drag type wind turbine. Although the startability is improved, when the wind turbine starts to rotate, the drag type wind turbine portion becomes a resistance to rotation, and the rotation efficiency is lowered.

Solidity is one of the important characteristic coefficients that characterize the performance of a wind turbine. Solidity is defined as "the ratio of the total projected area of the rotor blades to the swept area of the wind turbine". However, the projected area here means projection on a plane perpendicular to the wind direction.

Generally, the drag type wind turbine has a larger solidity than the lift type wind turbine, so the torque generated in the blade is larger than that of the lift type wind turbine. The drag-type wind turbine is better for starting from a stationary state to a weak wind. However, it cannot rotate at a peripheral speed higher than the wind speed acting on the wind turbine.

On the other hand, although the lift type wind turbine has a small solidity, it can rotate at a high peripheral speed ratio that is several times higher than the wind speed because the lift generated by the blade is used. Therefore, the energy efficiency obtained is higher in the lift type wind turbine than in the drag type wind turbine. However, for example, the vertical type Darius type wind turbine belonging to the lift type wind turbine has a demerit that the startability is poor. It is often devised by combining it with the Savonius type of drag-type wind turbine (Patent Document 1).

In a vertical-axis wind turbine, a method has been proposed in which a lift-type wind turbine unit and a drag-type wind turbine unit are arranged above and below the rotation axis to be mechanically connected or disconnected (Patent Document 2).

As an improvement of the Savonius type wind turbine, which is a vertical axis wind turbine, the wind receiving surface is divided into a plurality of vertically long blades, each of which has a rotation axis on one of its vertical sides, and the direction of rotation of the wind receiving surface is behind. It can be opened and closed freely on the side, and when the wind receiving surface is a tail wind, each wing closes and receives the wind, and when the wind is headwind, each wing opens to reduce the wind resistance (Patent Document 3). ). Drag-type wind turbines cannot obtain large energy efficiency because the receiving surface cannot move faster than the wind speed.

A proposal is made in which a lift type wind turbine blade is combined with the proposal of Patent Document 3 (Patent Document 4). In the high-speed rotating wind region, the vertical blade is in an open state regardless of the wind direction. However, the vertical blade becomes a resistance to rotation, even if it is a little, and reduces energy efficiency.

The beam that supports the expandable and contractible wind element from both sides has a sharp angle at the joint with each rotation axis, and the support beam is parallel to the rotation axis on the lower side and receives on the upper side. A technique for a wind turbine rotating device capable of maximizing the wind surface is described (Patent Document 5). Although it is illustrated to be installed on a floating structure on the water, if the floating structure is shaken or tilted due to disturbance, the vertical upper wind receiving surface does not reach the maximum receiving area.

Japanese Patent Application Laid-Open No. 56-143367 JP 2016-205255 JP 2012-017729 JP 2015-7417 Korean Registered Patent No. 10-1034924

An object of the present invention is to provide a wind turbine having excellent startability and high energy efficiency.

The wind turbine has a structure in which the axis of rotation is horizontal and intersects the wind direction, for example, a straight-wing vertical-axis wind turbine is tilted sideways.

The direction of rotation of the wind turbine is such that the blade is from windward to leeward on the upper side of the rotation axis, and the blade is from leeward to leeward on the lower side.

The wind turbine blade is provided with a lid that can be freely opened and closed toward the rotating shaft on the inside of the blade rotation, that is, on the surface on the rotating shaft side. For example, in a form in which the lid is opened and closed using a support shaft, the support shaft for opening and closing the lid is the rotation progress side, and the free side is the rotation rear side. The opening angle of the lid is restricted within a desired range.

When the wind turbine is stationary or at a low rotation speed, the lid of the blade above the rotation shaft opens downward within the range limited by its own weight, and the opened lid becomes the wind receiving surface and generates the starting torque of the wind turbine.

When the wind turbine is stationary or the blade is below the axis of rotation when the rotation speed is low, the lid is pushed by its own weight and the wind to close.

When the rotation speed of the wind turbine is high enough, the blade lid will not open. This is because the centrifugal force acting on the lid and the traveling wind pressure that the blade rotates presses against the blade.

According to the present invention, when the blade is located above the rotation axis when the wind turbine is stationary or the rotation speed is low, the lid on the rotation axis side of the blade hangs down and opens due to its own weight. The opening angle of the lid is limited by the stopper, and the lid becomes the wind receiving surface, increasing the solidity and improving the maneuverability of the wind turbine. On the other hand, when the blade is located below the axis of rotation, the lid receives its own weight or wind and closes to the blade side. When the blade moves to the headwind side, the wind receiving surface becomes smaller.

When the number of rotations of the wind turbine becomes sufficiently large, the lid of the blade is always closed to the blade side regardless of the positional relationship with the rotation shaft due to the centrifugal force received and the traveling wind of rotation. Since the solidity is small and the blade continues to generate lift, it can rotate at high speed and improve energy efficiency.

The wind turbine installed on the floating structure is shaken by the influence of the disturbance caused by the wind and the waves on the water surface. For example, FIG. 7 shows a state in which the wind turbine is inclined to the windward side or the leeward side. Since the opening and closing of the lid provided on the blade is generated by its own weight and the traveling wind pressure, it functions according to the vertical vertical positional relationship without being affected by the tilted state of the wind turbine.

According to the first embodiment of the present invention, the wind turbine is stationary or has a low speed rotation range, and the blade is above the rotation axis. Perspective view of the open state from the rotation axis side In the first embodiment of the present invention, a state in which the wind turbine is in the high speed rotation range and the lid on the inner surface of the rotation of the blade above the rotation axis is closed to the blade side is viewed from the rotation axis side. Perspective view In the first embodiment of the present invention, the wind turbine is stationary or in the low speed rotation range, and the lid on the inner surface of the rotation of the blade above the rotation axis opens by its own weight and is lowered to the position of the stopper. , Side view of a schematic configuration example in which the lid of the blade below the rotation axis is closed by its own weight. The first embodiment of the present invention is a schematic configuration in which the wind turbine rotates at a high speed clockwise in the figure around the axis of rotation, and the lids on the inner surface of the rotation of all the blades are closed. Side view of the example. The lid is shown slightly away from the blade for the sake of clarity, but in actual operation it is integrated with the blade and does not become a resistance to rotation. A perspective view of a schematic configuration example according to the first embodiment of the present invention, showing a state in which a wind turbine to which a blade with a lid is applied is loaded on a floating body on water. A perspective view of a schematic configuration example showing a state in which a wind turbine to which a blade with a lid is applied is loaded on a rotary table according to a second embodiment of the present invention. It is a perspective view when the wind turbine part of this invention is inclined to the windward side or the leeward side.

(First embodiment)
FIGS. 1 and 2 show the open / closed state of the blade and the lid of the present invention.

The blade 2 applied to the wind turbine equipment of the present invention has an airfoil shape. The opened lid 4a is connected to the blade by a support shaft 7 and can be freely opened and closed. The position of the support shaft 7 on the blade is arbitrary, and may be close to the leading edge portion of the blade or close to the trailing edge portion. The position of the support shaft 7 on the blade is also included to be on the outside of the rotation, which is the opposite side of the rotation axis. The position of the free end of the lid is also free, and may be the trailing edge of the blade, or any position between the trailing edge and the support shaft. The longer the length between the support shaft and the free end of the lid, the larger the area used as the wind receiving part.

The length of the lid with respect to the blade length direction may be one piece over the entire length, may be divided into a plurality of pieces, or may be arranged intermittently.

When the lid is closed, there should be as little unevenness as possible so as not to cause air resistance.

When the lid is closed, it is desirable that the surface of the lid be shaped to be part of the airfoil profile of the entire blade.

3 and 4 show the configuration of the first embodiment of the present invention.

In the blade 2 applied to the wind turbine equipment of the present invention, one or a plurality of blades are laid at equal intervals around the rotation shaft 1 of the wind turbine via the arm 3. The axis of rotation is horizontal and has a positional relationship that intersects the wind direction of the wind 31. The leading edge of the blade should face leeward when the blade is at the top of the rotation. A lid 4 (the open lid is 4a) is attached to the surface of the blade near the rotation axis, with an axis parallel to the rotation axis as a support axis and freely opening and closing toward the rotation axis. The lid is integrated with the blade in the closed state, and the maximum opening angle is up to the stopper 5 in the open state. When the wind turbine rotates, electricity is generated by the generator 15 connected to the rotating shaft.

The stopper may be attached to the arm 3, for example. A method of connecting the lid and the blade with a wire to limit the maximum opening angle of the lid may also be used. By limiting the maximum opening angle of the lid with a stopper or the like, an appropriate wind receiving surface can be obtained.

FIG. 3 shows a side view of the first embodiment in the case where the wind is weak and the wind turbine is stopped or the rotation speed is low. The lid of the blade above the axis of rotation opens by its own weight. The maximum opening angle is limited by the position of the stopper. Compared to the state where the lid is not opened, the solidity is increased because the wind receiving area is increased by the amount that the lid is opened, and the starting torque of the wind turbine rotation is increased.

The lid of the blade located below the axis of rotation closes to the blade side due to its own weight. Since the wind receiving area is smaller than when the lid is open, the wind resistance when the blade returns to the windward side can be reduced.

FIG. 4 shows a state when the wind speed is sufficiently high. The lid of the blade is pressed against the blade by the centrifugal force of the wind turbine and the traveling wind of rotation, and it is always closed regardless of the position. That is, the solidity becomes smaller. It is possible to eliminate the restriction of the rotation speed due to the wind resistance of the wind receiving portion as seen in the vertical axis drag type wind turbine.

FIG. 5 shows a state in which the first embodiment of the present invention is installed in a floating structure.

Both ends of the rotating shaft of the wind turbine are supported by columns 13 and connected to the floating body 11. In the present embodiment, the floating body is a catamaran composed of two bodies, and the two floating bodies are connected by a connecting stand 12 to form a wind turbine facility. The wind turbine equipment is moored to the seabed, surrounding structures, ships, etc. by the mooring line 14, and is blown away by the wind so that the wind turbine rotation axis and the wind direction always intersect each other.

When the wind turbine rotates, the generator 15 connected to the rotating shaft 1 is rotated to generate electricity. Further, the rotation of the wind turbine may be used as direct power.

The electricity generated by the generator is stored in a storage battery loaded in the floating body and used to drive the equipment loaded in the floating body, or the surrounding water is electrolyzed to generate hydrogen and stored in a tank. It can be supplied to the outside through electric wires.

FIG. 7 shows a state in which the floating structure is swaying back and forth in the wind direction with the first embodiment of the present invention placed on the floating structure. When the floating structure is shaken, the support column 13 is tilted. However, the attitude of the wind turbine and its axis of rotation does not change with respect to the wind direction. In addition, the sweeped area of the wind turbine equipment does not change.

(Second embodiment)
FIG. 6 shows the overall configuration of the second embodiment of the present invention.

In the blade 2 applied to the wind turbine equipment of the present embodiment, a plurality of blades are laid at equal intervals around the rotation shaft 1 of the wind turbine via the wind turbine wheel 6. The axis of rotation is horizontal and has a positional relationship that intersects the wind direction of the wind 31. The leading edge of the blade should face leeward when the blade is at the top of the rotation. A lid 4 (the open lid is 4a) that freely opens and closes toward the rotation axis is attached to the surface of the blade near the rotation axis with the opening / closing shaft in a direction parallel to the rotation axis as a fulcrum. The lid is integrated with the blade in the closed state, and the maximum opening angle is up to the stopper 5 mounted on the wind turbine wheel in the open state. When the windmill rotates, the windmill wheel turns the generator wheel, and the generator 15 connected to the generator wheel generates electricity.

Both ends of the rotary shaft are supported by the columns 13 via bearings 21 and fixed to the wind turbine stand 22 to form the wind turbine equipment. By laying the tail feathers 24 in the wind turbine equipment, the positional relationship is always such that the wind turbine rotation axis and the wind direction intersect. The windmill wheel is located off the center of rotation of the generator wheel, and the center of rotation of the windmill pedestal is coaxial with the center of rotation of the generator wheel, so even if the wind direction changes and the direction of the windmill equipment changes, the generator Can generate electricity with its position fixed.

The electricity generated by the generator can be stored in a storage battery and used as an independent power source, or can be connected to a wiring system and used over a wide area.

The wind turbine equipment and the wind turbine blade of the present invention may be used in a floating offshore wind turbine for a horizontal and horizontal axis wind turbine in which the crossing relationship between the rotation axis of the wind turbine and the wind direction does not change even if the floating body is shaken. ..

1 Rotating shaft 2 Blade 3 Arm 4 Lid 4a Open lid 4b Closed lid 5 Stopper 6 Windmill wheel 7 Lid support shaft 11 Floating body 12 Connecting pedestal 13 Pillar 14 Mooring line 15 Generator 21 Bearing 22 Windmill pedestal Rotating table 23 Generator wheel 24 Ou 31 Wind 41 Wind turbine unit of the equipment of the present invention tilted forward with respect to the wind direction 42 Wind turbine unit of the equipment of the present invention at a reference position with respect to the wind direction 43 Wind turbine unit of the equipment of the present invention tilted backward with respect to the wind direction.

Claims (2)

The rotation axis 1 is horizontal and is in a positional relationship intersecting the wind direction, and at least one blade 2 is provided around the rotation axis, and the blade is a windmill that rotates from the wind to the leeward above the rotation axis. It is a facility, and a lid 4 that can freely open and close a part or all of the surface of the blade near the rotation axis within a predetermined range is provided on the rotation axis side, and is above the rotation axis when the rotation speed of the wind turbine is low. The lid of the blade opens to become a wind receiving surface and generates starting torque, the lid of the blade below the rotation axis closes to reduce the resistance of the head wind, and when the rotation speed is high, the lid moves to the blade side due to centrifugal force and traveling wind pressure. A windmill blade and its windmill equipment characterized by being closed to suppress rotational air resistance. Floating wind turbine equipment in which the wind turbine equipment is loaded on a mooring type floating body.

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