CN217602833U - Wind turbine blade damping device and large wind turbine blade comprising same - Google Patents

Abstract

The utility model relates to a wind energy conversion system blade damping device and contain device's large-scale wind energy conversion system blade, wherein shake the loss-resistant device and include the supporter, first spring, the second spring, third spring and fourth spring, first spring, the second spring, the one end of third spring and fourth spring is connected to the supporter respectively, all springs and supporters are on a plane, and the direction of first spring and third spring is the same, second spring and fourth spring are on a straight line and perpendicular with first spring, the second spring, all be equipped with the connecting piece that is used for connecting wind energy conversion system blade inner wall on the other end of third spring and fourth spring. Compared with the prior art, the utility model has the advantages of improve leaf point portion anti vibration damage resistance ability.

Description

Wind turbine blade damping device and large wind turbine blade containing the same

technical field

The utility model relates, in particular, to a wind turbine blade damping device and a large wind turbine blade containing the device.

Background technique

Since the 21st century, with the increasingly serious energy problems, the utilization of wind energy in various countries has reached a stage of rapid development. Wind rotor blades are the core components of wind turbines that convert wind energy into mechanical energy. The reliability of wind rotor blades plays a crucial role in the safe operation of wind turbines. Due to the change of wind speed and direction, the working environment of wind turbines is very complicated. The wind turbine is exposed to a series of complex loads such as aerodynamic load, centrifugal load, and gravity load for a long time. The tower has its own natural frequency, and the generator works to generate vibration frequencies. If the frequency of the blades resonates with any of these frequencies, it will cause fatigue damage. One of the main factors of blade damage is the resonance phenomenon of the blade, which will aggravate the fatigue of the blade material, reduce its effective service life, and even lead to damage and fracture of the blade in severe cases. The load on the mechanism will be amplified due to the resonance phenomenon, and the fuselage or blade will shake seriously, affecting its power generation efficiency, and even causing serious damage. Therefore, the structural dynamic design of the blade is particularly critical. Modal analysis is a common method for studying the dynamic characteristics of modern structures, and it is also an important application of the system identification method in the field of engineering vibration. According to the research results of the natural vibration characteristics, it can effectively avoid the resonance caused by the same frequency of the external excitation and the natural vibration, and prevent the damage of the mechanical structure.

Many systematic studies have been made on the natural frequencies and modal shapes of wind turbines at home and abroad. There are very few additional reinforcements on the blade structure to resist vibration. The blade, the most easily damaged structure in wind turbines, is very necessary to strengthen its structure to resist vibration and damage, especially in complex environments, wind turbine blades are likely to resonate with the external environment, causing wind damage to the wind turbine, reducing the service life of the wind turbine.

SUMMARY OF THE INVENTION

The purpose of the utility model is to provide a wind turbine blade damping device and a large wind turbine blade containing the device.

The purpose of the present utility model can be achieved through the following technical solutions:

A wind turbine blade damping device, comprising a support body, a first spring, a second spring, a third spring and a fourth spring, one end of the first spring, the second spring, the third spring and the fourth spring are respectively connected to the support All springs and the supporting body are on the same plane, the first spring and the third spring are in the same direction, the second spring and the fourth spring are on a straight line and perpendicular to the first spring, the first spring, the second spring The other ends of the spring, the third spring and the fourth spring are all provided with connecting pieces for connecting the inner wall of the wind turbine blade.

The connecting pieces on the first spring, the second spring and the third spring are cone connecting pieces, and the connecting pieces on the fourth spring are column connecting pieces.

The first spring and the third spring are in a straight line.

The basic stiffness of the first spring, the second spring, the third spring and the fourth spring is 1500N/m ³ -20000N/m ³ .

The basic stiffness of the first spring, the second spring, the third spring and the fourth spring is 10000 N/m ³ .

The support body is a cube.

A large wind turbine blade is provided with two anti-vibration and anti-damage devices as described in any one of the above, and the anti-vibration and anti-damage devices are parallel to the blade section of the blade.

One anti-vibration and anti-loss device is arranged at a position relative to the blade height of 0.47-0.5, and the other anti-vibration and anti-loss device is arranged at a position relative to the blade height of 0.86-0.91.

The first spring is connected to the inner wall of the top end of the pressure surface, the third spring is connected to the inner wall of the top end of the suction surface, and the second spring is connected to the inner wall of the leading edge of the blade element.

The fourth spring is connected to the inner wall of the pressure surface.

Compared with the prior art, the utility model has the following beneficial effects:

1) Each wind turbine blade is equipped with two cross elastic anti-vibration and anti-loss devices. Through modal analysis, it is found that the natural frequency of the wind turbine blade is increased, which is higher than most frequencies in the environment, which reduces the number of wind turbine blades. The possibility of damage to the wind turbine due to resonance.

2) The wind turbine blade with cross elastic anti-vibration and anti-loss device is installed. Through modal analysis, it is found that the maximum deformation of the wind turbine blade when resonance occurs is greatly reduced, which makes the wind turbine blade have stronger anti-resonance ability. The damage to the wind turbine blades by resonance is reduced, and the service life of the wind turbine is prolonged.

3) Compared with the non-installed wind turbine blade with the cross elastic anti-vibration and damage resistance device installed, the maximum deformation of the wind turbine blade without the installation is located at the blade tip, while the cross elastic anti-vibration resistance device is installed. The maximum modal deformation of the wind turbine blade with damage device moves from the tip to the middle of the blade. This enhances the anti-vibration and damage resistance of the most fragile blade tip, and prolongs the service life of the wind turbine.

Description of drawings

1 is a schematic diagram of the structure of a 5MW wind turbine blade equipped with a cross elastic anti-vibration and anti-loss device of the present utility model;

Fig. 2 is the schematic diagram of blade section;

Fig. 3 is the installation schematic diagram of the anti-vibration and anti-loss device;

Figure 4 is a graph showing the comparison of the modal frequency and the maximum deformation of the first three modes under different spring foundation stiffnesses under the static state of the wind turbine and the comparison of the cross-vibration and loss-resistance device without the installation of the cross-resistance and loss-resisting device, in which, (a) is the static wind turbine. The line graph comparing the next-order modal frequency of different spring foundation stiffness and the first-order modal frequency without cross anti-vibration and anti-damage device under different conditions. The line graph comparing the second-order modal frequency with that without the cross anti-vibration and anti-loss device, (c) is the third-order modal frequency of the wind turbine under different spring foundation stiffness in the static state and the third-order modal frequency without the cross anti-vibration and anti-loss device. The modal frequency comparison chart; (d) is the maximum deformation of the first three modes under different spring stiffness under the static state of the wind turbine and the maximum deformation of the first three modes without the cross anti-vibration and damage device. picture;

Figure 5 is a broken line chart comparing the modal frequency and the maximum deformation of the first three modes under different spring foundation stiffnesses under the rated working state of the wind turbine and the cross-vibration and loss-resisting device without the installation. Among them, (a) is the wind turbine. The line graph comparing the next-order modal frequency of different spring foundation stiffness under rated working condition and the first-order modal frequency without cross anti-vibration and anti-loss device installed, (b) is the second-order modal frequency under different spring foundation stiffness under rated working condition of wind turbine The line chart comparing the modal frequency and the second-order modal frequency without the cross anti-vibration and damage device, (c) is the third-order modal frequency under the different spring foundation stiffness under the rated working state of the wind turbine and the cross-vibration-resistant device without The broken line diagram of the comparison of the third-order modal frequency of the damage device, (d) the maximum deformation of the first three-order mode under different spring foundation stiffness under the rated working state of the wind turbine and the first three-order mode without the cross-vibration and damage-resistant device. Maximum deformation comparison line chart;

Figure 6 is a scatter plot of the relative blade height position of the maximum deformation of the wind turbine when the spring is at a basic stiffness of 10,000 N/m ³ in a static or rated working state and a cross-vibration and loss-resistant device without the installation.

Among them: 1. Blade body, 2. Anti-vibration and anti-damage device, 3. Anti-vibration and anti-damage device, 4, 5, 7, Cone connection, 6, First spring, 8, Second spring, 9, Column connection , 10, support body, 11, leaf element, 12, third spring, 13, fourth spring, A, the inner wall of the leading edge of the blade element, B, the inner wall of the top of the suction surface, C, the inner wall of the trailing edge of the blade element, D, the inner wall of the leading edge of the blade element and The connecting line between the inner wall of the leading edge of the blade element, the inner wall of the top of the pressure surface, and the inner wall of the top of the suction surface is perpendicular to the inner wall of a point on the pressure surface, E, the inner wall of the top of the pressure surface.

Detailed ways

The present utility model will be described in detail below with reference to the accompanying drawings and specific embodiments. This embodiment is implemented on the premise of the technical solution of the present invention, and provides a detailed implementation manner and a specific operation process, but the protection scope of the present invention is not limited to the following embodiments.

A wind turbine blade damping device, as shown in Figures 1 to 3, includes a support body 10, a first spring 6, a second spring 8, a third spring 12 and a fourth spring 13, the first spring 6, the second spring One ends of the spring 8, the third spring 12 and the fourth spring 13 are respectively connected to the support body 10, all the springs and the support body are on a plane, and the first spring 6 and the third spring 12 are in the same direction, the second spring 8 and The fourth spring 13 is on a straight line and is perpendicular to the first spring 6, and the other ends of the first spring 6, the second spring 8, the third spring 12 and the fourth spring 13 are all provided with connections for connecting to the inner wall of the wind turbine blade pieces. The support body 10 is a cube.

In some embodiments, the connectors on the first spring 6 , the second spring 8 and the third spring 12 are cone connectors, and the connectors on the fourth spring 13 are column connectors 9 .

In some embodiments, the first spring 6 and the third spring 12 are in a straight line.

In some embodiments, the basic stiffnesses of the first spring 6 , the second spring 8 , the third spring 12 and the fourth spring 13 are 1500 N/m ³ -20000 N/m ³ . In a certain embodiment, the basic stiffness of the first spring 6 , the second spring 8 , the third spring 12 and the fourth spring 13 is 10000 N/m ³ .

A large-scale wind turbine blade is provided with two anti-vibration and anti-loss devices as above, and the anti-vibration and anti-loss devices are parallel to the blade section of the blade. One anti-vibration and anti-loss device is arranged at a position relative to the blade height of 0.47-0.5, and the other anti-vibration and anti-loss device is arranged at a position relative to the blade height of 0.86-0.91. The first spring 6 is connected to the inner wall of the top end of the pressure surface, the third spring 12 is connected to the inner wall of the top end of the suction surface, and the second spring 8 is connected to the inner wall of the leading edge of the blade element. The fourth spring 13 is connected to the inner wall of the pressure surface.

Specifically, FIG. 1 shows a schematic structural diagram of the horizontal axis wind turbine blade body 1 and the cross elastic anti-vibration and anti-loss devices 2 and 3 of the present invention. Two cross elastic anti-vibration and anti-loss devices are arranged on one wind turbine blade. device. Two cross elastic anti-vibration and anti-damage devices are installed at positions of 0.48 and 0.89 relative to the blade height, respectively. Both units are installed in the same way.

Figures 2 and 3 show the schematic diagram of the blade element for installing the cross elastic anti-vibration and anti-loss device of the present invention. A cone connecting piece 4, 5, 7 and a column connecting piece 9 are composed. The blade element outer contour curve ABC is the suction surface, and the blade element outer contour curve AEC is the pressure surface. The chord line is the straight line AC between the leading edge point A and the trailing edge point C, the inner wall E at the top of the pressure surface is the farthest point from the vertical distance of the pressure surface inner wall from the chord line, and the inner wall B at the top of the suction surface is the vertical distance between the inner wall of the suction surface and the chord line. Further. The three conical connectors 4, 5, and 7 are respectively located on the top inner wall B of the suction surface of the wind turbine blade, the top inner wall E of the pressure surface, and the inner wall A of the leading edge of the blade element. Connect BE, pass the point A as the vertical line of BE and cross the pressure surface on the inner wall at point D. AD is perpendicular to BE, and D is a point on the inner wall of the pressure plane. A post connector 9 is used to connect the end of the spring to the inner wall D. The springs 6, 8, 12, and 13 are in a free state, which can be compressed or pulled, and the basic stiffness of the springs is 1500N/m ³ -20000N/m ³ . where the base stiffness is defined as the pressure value that produces the normal deformation of the base unit. The support body 10 is a cube of 40×40×40 mm. The three conical connecting pieces 4, 5, 7 are smoothly connected with the inner wall of the wind turbine blade, and the springs 6, 8, 12, 13 are also smoothly and fixedly connected with the four connecting pieces 4, 5, 7, 9 and the support body 6.

Referring to Fig. 3, the springs 6, 8, 12, 13 are arranged in a cross circumferential direction, which makes when the wind turbine blades resonate, the springs 6, 8, 12, 13 will give a tension or pressure to the blades that will be twisted and deformed , to prevent the blade from being twisted and deformed due to resonance, and at the same time to increase the resonance frequency, reduce the possibility of resonance with the outside world, and prolong the service life. At the same time, it is also very important for the basic stiffness of the springs 6, 8, 12, 13 to be at an appropriate value. If the basic stiffness of the springs 6, 8, 12, and 13 is too low, the springs 6, 8, 12 arranged in the cross circumferential direction when resonance occurs. , 13 will be laterally twisted and deformed, which will destroy the cross elastic anti-vibration and anti-damage device. If the basic stiffness of the springs 6, 8, 12, and 13 is too high, the springs 6, 8, 12, and 13 will give a pulling force or pressure to the blades that will be twisted and deformed, and the twisting amplitude of the wind turbine will be large. Therefore, it is very important to find out the appropriate value of the basic stiffness of the springs 6, 8, 12 and 13 for the present utility model.

The modal analysis of wind turbine blades with and without cross elastic anti-vibration and damage-resistant device was carried out under the conditions of static and rated operating speed of 1.266 rad/s and different spring foundation stiffness selection conditions. Since the first three orders concentrate the main energy of the vibration, the first three order modal frequencies can be regarded as the natural frequencies of the wind turbine blade. Figures 4 and 5 show the comparison of the first three-order modal frequencies and the maximum deformation of the wind turbine under different spring stiffnesses in the static state of the wind turbine and the comparison of the cross-vibration and anti-loss device without the addition of the broken line diagram and the difference in the rated working state of the wind turbine. The comparison line chart of the first three-order modal frequency and the maximum deformation amount under the spring stiffness and without the cross-vibration and damage-resistance device. Through the modal analysis calculation, it is found that when the spring foundation stiffness is lower than 1500N/m ³ , the spring will undergo lateral torsional failure during resonance. When the spring foundation stiffness is higher than 20000N/m ³ , the twisting amplitude of the wind turbine is too large at this time. Therefore, the device of the utility model is suitable for the spring foundation stiffness between 1500N/m ³ -20000N/m ³ . Through (a), (b), (c) of Figure 4 and (a), (b), (c) of Figure 5, it is found that the first three times when the wind turbine is rotating and stationary without the cross anti-vibration and anti-loss device are installed. The first-order modal frequencies are all about 0.6HZ, and the first three-order modal frequencies are about 2.5-2.7HZ when the cross anti-vibration and anti-loss device is installed under different basic stiffnesses when the wind turbine is rotating and stationary. Therefore, the natural frequency of the wind turbine is about 0.6HZ when the cross anti-vibration and anti-loss device is not installed. After adding the cross elastic anti-vibration and anti-loss device, the natural frequency of the wind turbine becomes 2.5-2.7HZ under different basic stiffness. , the natural frequency is increased by about 77%. At the same time, it can be seen that with the increase of the foundation stiffness, the first three modal frequencies of the wind turbine also increase with a small increase. According to Fig. 4(d) and Fig. 5(d), it is found that the maximum deformation of the static wind turbine blade decreases by about 26%-40% when resonance occurs. The maximum deformation of the wind turbine blade is reduced by about 20%-40% during rated operation. All of this reduces the possibility that the wind turbine blades are greatly damaged due to resonance, and increases the service life of the wind turbine.

In addition, because the spring foundation stiffness has a wide range of application, the spring is analyzed here under the basic stiffness of 10000N/ ^m3 , and the same conclusion can be obtained under other applicable basic stiffness conditions. Figure 6 shows a scatter plot comparing the maximum deformation of the wind turbine relative to the position of the blade height when the spring is at a basic stiffness of 10,000 N/m ³ under the static or rated working state of the wind turbine and that without the cross anti-vibration and anti-damage device. It can be seen that the maximum deformation of the blade when the resonance occurs when the cross anti-vibration and damage-resistant device is installed is compared with the non-installed device, and the maximum deformation of the blade moves from the position of the blade tip to the middle of the blade, which makes the fragile blade tip protected when resonance occurs. the service life of the wind turbine.

The above are only the preferred embodiments of the present invention. The present invention is not limited to the above examples, and does not limit the scope of implementation of the present invention. It can be understood that researchers in the field do not deviate from the spirit and Other improvements and changes directly derived or thought of under the premise of the concept should be considered to be included in the protection scope of the present invention.

Claims (10)

1. The utility model provides a wind turbine blade damping device, a serial communication port, including supporter (10), first spring (6), second spring (8), third spring (12) and fourth spring (13), first spring (6), second spring (8), the one end of third spring (12) and fourth spring (13) is connected to supporter (10) respectively, all springs and supporters are on a plane, and the direction of first spring (6) and third spring (12) is the same, second spring (8) and fourth spring (13) are on a straight line and perpendicular with first spring (6), all be equipped with the connecting piece that is used for connecting wind turbine blade inner wall on the other end of first spring (6), second spring (8), third spring (12) and fourth spring (13).

2. The wind turbine blade damping device according to claim 1, wherein the connecting members of the first spring (6), the second spring (8) and the third spring (12) are cone connecting members, and the connecting member of the fourth spring (13) is a column connecting member (9).

3. A wind turbine blade damping device according to claim 1, characterised in that the first spring (6) and the third spring (12) are in a straight line.

4. A wind turbine blade damping device according to claim 1, characterised in that the base stiffness of the first spring (6), the second spring (8), the third spring (12) and the fourth spring (13) is 1500N/m ³ --20000N/m ³ 。

5. A wind turbine blade damping device according to claim 4, characterised in that the base stiffness of the first (6), second (8), third (12) and fourth (13) springs is 10000N/m ³ 。

6. A wind turbine blade damping device according to claim 1, characterised in that the support body (10) is a cube.

7. A large wind turbine blade incorporating a device as claimed in any one of claims 1 to 6 wherein there are two anti-vibration and anti-damage devices arranged parallel to the cross-section of the blade.

8. The large wind turbine blade according to claim 7, wherein one of the anti-vibration and anti-damage devices is disposed at 0.47-0.5 of the relative blade height, and the other anti-vibration and anti-damage device is disposed at 0.86-0.91 of the relative blade height.

9. Large wind turbine blade according to claim 7, characterised in that the first spring (6) is attached to the pressure side tip inner wall, the third spring (12) is attached to the suction side tip inner wall and the second spring (8) is attached to the leaflet leading edge inner wall.

10. Large wind turbine blade according to claim 9, characterised in that the fourth spring (13) is attached to the pressure surface inner wall.

Images