A tuned mass damper for a floating offshore wind turbine

Abstract

The application discloses a tuned mass damper device for a floating offshore wind turbine, which comprises a top plate and a bottom plate installed on the inner wall of a wind turbine tower, and a mass block arranged between the top plate and the bottom plate; a plurality of rigid connecting rods are hingedly connected on the inner wall of the wind turbine tower at equal intervals in the circumferential direction, the ends of the rigid connecting rods are hingedly connected with the mass block, and dampers are installed on the rigid connecting rods; upper and lower vertical damping mechanisms are respectively installed on the upper and lower ends of the mass block, the end of the upper vertical damping mechanism is connected with the top plate, and the end of the lower vertical damping mechanism is connected with the bottom plate. The application carries out multi-dimensional vibration control on the wind turbine; the tuned mass damper composed of the mass block, the rigid connecting rods and the dampers is used to slow down the movement of the wind turbine in the horizontal direction, and when the wind turbine moves vertically, the dampers inhibit the vertical movement of the wind turbine by energy dissipation through the movement of the mass block, the upper vertical damping mechanism and the lower vertical damping mechanism, so that the wind turbine is kept stable.

Description

Technical Field

[0001] This invention relates to the field of vibration control technology, and in particular to a tuned mass damping vibration reduction device for floating offshore wind turbines. Background Technology

[0002] Wind energy, as a clean, pollution-free, renewable, widely distributed, and abundant energy source, has attracted much attention and importance. Offshore wind energy, compared to onshore wind energy, has advantages such as longer power generation time and higher wind resource quality, making it a current hot topic in wind energy development. To obtain more wind resources, offshore wind turbines are gradually being developed towards larger scale and deeper waters, with increasingly longer turbine blades and taller towers. The long, flexible characteristics of the turbine blades and towers make vibration problems more prominent in the complex marine environment, directly affecting the safety and stability of the turbines.

[0003] Deep-sea wind turbines typically use floating foundations. However, floating wind turbines experience more pronounced vibration issues due to the combined effects of wind, waves, and currents. Without proper control, this poses a significant threat to the safe operation of the turbine. Relying on increasing the strength and rigidity of the turbine itself to resist fatigue loads caused by vibration would greatly increase the investment cost of the wind turbine. Therefore, vibration control has become an effective method to address this problem. There are three main vibration control strategies: passive, semi-active, and active. Passive control is widely used due to its simplicity and lack of energy input requirement.

[0004] As a tall structure, wind turbines can draw on the vibration control methods of existing high-rise buildings in terms of vibration control technology. However, the ordinary tuned mass dampers used in high-rise buildings transfer some of the energy of structural vibration to the auxiliary mass-spring-damping cylinder system connected to the main structure. Ordinary tuned mass dampers provide vibration reduction in a single direction, and their function is limited under complex environmental loads. They cannot avoid vibration in the heave direction, and the displacement of the oscillator is large, so they cannot play a role in wind turbines with limited space.

[0005] While there are existing technologies that incorporate hysteretic dampers in tower structures for vibration reduction, these devices simply add a mass ring and a ring-shaped soft steel damper to the traditional tuned mass damper structure. When wind and water loads are applied, the load is transferred to the ring-shaped soft steel damper through the mass sphere and mass ring, reducing the damper oscillator displacement. However, this device can only dissipate the unit's sway and roll vibration energy; it cannot improve the unit's heave motion.

[0006] Therefore, there is an urgent need to propose a tuned mass damping vibration reduction device for floating offshore wind turbines to solve the above-mentioned technical problems. Summary of the Invention

[0007] The purpose of this invention is to provide a tuned mass damping vibration reduction device for floating offshore wind turbines, so as to solve the problems existing in the prior art.

[0008] To achieve the above objectives, the present invention provides a tuned mass damping vibration reduction device for a floating offshore wind turbine, comprising a top plate and a bottom plate fixedly installed on the inner wall of the wind turbine tower, wherein a mass block is disposed between the top plate and the bottom plate;

[0009] Multiple rigid connecting rods are hinged at equal intervals along the circumference of the inner wall of the wind turbine tower. The ends of the rigid connecting rods are hinged to the mass block, and dampers are installed on the rigid connecting rods.

[0010] An upper vertical damping mechanism and a lower vertical damping mechanism are respectively installed at the upper and lower ends of the mass block. The end of the upper vertical damping mechanism is connected to the top plate, and the end of the lower vertical damping mechanism is connected to the bottom plate.

[0011] Preferably, the lower vertical damping mechanism includes multiple spring bases mounted on the base plate, with a spring installed at the top of each spring base and the top of the spring connected to the bottom of the mass block; multiple hydraulic rods are hingedly mounted on the base plate, with the ends of the hydraulic rods hinged to the mass block, and the hydraulic rods are evenly spaced along the circumference of the mass block.

[0012] Preferably, the upper vertical damping mechanism includes a central hanging column installed in the middle of the top plate, and multiple damper groups are arranged at equal intervals along the circumference of the central hanging column. The damper groups are connected to ropes, and the ends of the ropes are fixedly connected to the bottom of the side wall of the mass block.

[0013] Preferably, multiple side columns are fixedly connected at equal intervals along the circumference of the central column on the top plate, and the side columns are arranged in a one-to-one correspondence with the damper group;

[0014] The damper assembly includes an upper damper and a lower damper fixedly installed on the side wall of the central column. A movable pulley is fixedly installed at the end of the lower damper away from the central column. An upper fixed pulley and a lower fixed pulley are fixedly installed on the side column. The movable pulley is located between the upper fixed pulley and the lower fixed pulley. The end of the rope away from the mass block passes sequentially around the lower fixed pulley, the movable pulley, and the upper fixed pulley and is fixedly connected to the upper damper.

[0015] Preferably, the top of the lower fixed pulley is flush with the bottom of the movable pulley, the top of the movable pulley is flush with the bottom of the upper fixed pulley, and the top of the upper fixed pulley is flush with the upper damper.

[0016] Preferably, a plurality of fixing rings are fixedly connected at equal intervals along the circumference of the side wall of the mass block, and the fixing rings are arranged in a one-to-one correspondence with the ropes. The lower end of the ropes is connected to the bottom of the side wall of the mass block through the fixing rings.

[0017] Preferably, the rope is in a taut state when the fan is stationary.

[0018] Preferably, the damper, the upper damper, and the lower damper are all viscous dampers.

[0019] Preferably, both the top plate and the bottom plate are circular structures.

[0020] Preferably, the weight of the mass block accounts for 2% to 5% of the total weight of the fan.

[0021] Compared with the prior art, the present invention has the following advantages and technical effects:

[0022] 1. This invention provides multi-dimensional vibration control for wind turbines. It uses a tuned mass damper consisting of a mass block, a rigid connecting rod, and a damper to reduce the horizontal movement of the wind turbine. At the same time, when the wind turbine moves vertically, the damper suppresses the vertical movement of the wind turbine through the energy dissipation of the mass block, the upper vertical damping mechanism, and the lower vertical damping mechanism, thereby keeping the wind turbine stable.

[0023] 2. This invention can efficiently consume energy. When controlling the sway, lateral and heave motion of the wind turbine, the movement of the mass block in any direction drives the movement of the rope. The adjustment system composed of the rope, viscous damper and pulley block suppresses the movement of the mass block in any direction, so that the mass block can efficiently consume the energy of the movement in each direction in a small space inside the tower without causing the damper oscillator displacement to exceed the limit, thus slowing down the sway, lateral and heave motion of the wind turbine. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is an isometric schematic diagram of the overall structure of the present invention;

[0026] Figure 2 This is a front view schematic diagram of the overall structure of the present invention;

[0027] Figure 3 This is a top view of the overall structure of the invention;

[0028] Figure 4 This is a partial structural schematic diagram of the present invention;

[0029] In the diagram: 1. Wind turbine tower; 2. Top plate; 3. Bottom plate; 31. Mass block; 32. Hydraulic rod; 33. Spring base; 34. Spring; 4. Damper; 41. Rigid connecting rod; 5. Central hanging column; 51. Side hanging column; 521. Upper damper; 522. Lower damper; 53. Moving pulley; 541. Upper fixed pulley; 542. Lower fixed pulley; 6. Rope; 61. Fixing ring. Detailed Implementation

[0030] It should be noted that, unless otherwise specified, the embodiments and features described in this invention can be combined with each other. The described embodiments are merely some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of this invention. The invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0031] like Figures 1 to 4 As shown, the present invention provides a tuned mass damping vibration reduction device for a floating offshore wind turbine, including a top plate 2 and a bottom plate 3 fixedly installed on the inner wall of the wind turbine tower 1, and a mass block 31 is provided between the top plate 2 and the bottom plate 3.

[0032] Multiple rigid connecting rods 41 are installed at equal intervals along the circumference of the inner wall of the wind turbine tower 1 via ball joints. The ends of the rigid connecting rods 41 are connected to the mass block 31 via ball joints, and dampers 4 are installed on the rigid connecting rods 41.

[0033] The upper and lower vertical damping mechanisms are respectively installed at the upper and lower ends of the mass block 31. The end of the upper vertical damping mechanism is connected to the top plate 2, and the end of the lower vertical damping mechanism is connected to the bottom plate 3.

[0034] In use, the present invention moves horizontally within the wind turbine tower 1. Due to the presence of a damper 4 around the mass block 31, the movement of the mass block 31 generates a damping force, dissipating the energy of the horizontal movement of the wind turbine tower 1. Vertically, the mass block 31 moves vertically, and the lower vertical damping mechanism at the bottom of the mass block 31 dissipates the energy of the vertical movement of the wind turbine tower 1. Regardless of whether it is horizontal or vertical, the movement of the mass block 31 in any direction will drive the upper vertical damping mechanism to generate a damping force, thereby assisting in dissipating the energy of the wind turbine tower 1 in any direction.

[0035] Further optimization of the scheme: the lower vertical damping mechanism includes multiple spring bases 33 mounted on the base plate 3, with springs 34 mounted on the top of the spring bases 33, and the top of the springs 34 connected to the bottom of the mass block 31; multiple hydraulic rods 32 are mounted on the base plate 3 by means of ball joints, and the ends of the hydraulic rods 32 are connected to the mass block 31 by means of ball joints, with the hydraulic rods 32 evenly spaced along the circumference of the mass block 31.

[0036] Further optimization of the scheme: the upper vertical damping mechanism includes a central hanging column 5 installed in the middle of the top plate 2, and multiple damper groups 4 are evenly spaced along the circumference of the central hanging column 5. The damper groups 4 are connected to ropes 6, and the ends of the ropes 6 are fixedly connected to the bottom of the side wall of the mass block 31.

[0037] The scheme is further optimized by fixing multiple side columns 51 at equal intervals along the circumference of the central column 5 on the top plate 2. The side columns 51 are set one-to-one with the damper 4 groups.

[0038] The damper group 4 includes an upper damper 521 and a lower damper 522 fixedly installed on the side wall of the central column 5. A movable pulley 53 is fixedly installed at the end of the lower damper 522 away from the central column 5. An upper fixed pulley 541 and a lower fixed pulley 542 are fixedly installed on the side column 51. The movable pulley 53 is located between the upper fixed pulley 541 and the lower fixed pulley 542. The end of the rope 6 away from the mass block 31 passes through the lower fixed pulley 542, the movable pulley 53, and the upper fixed pulley 541 in sequence and is fixedly connected to the upper damper 521.

[0039] In a further optimized design, the top of the lower fixed pulley 542 is flush with the bottom of the movable pulley 53, the top of the movable pulley 53 is flush with the bottom of the upper fixed pulley 541, and the top of the upper fixed pulley 541 is flush with the upper damper 521.

[0040] In a further optimized design, multiple fixing rings 61 are fixedly connected at equal intervals along the circumference of the side wall of the mass block 31. The fixing rings 61 are set one-to-one with the ropes 6, and the lower end of the ropes 6 is connected to the bottom of the side wall of the mass block 31 through the fixing rings 61.

[0041] The scheme was further optimized so that rope 6 is in a taut state when the wind turbine is stationary.

[0042] To further optimize the design, damper 4, upper damper 521 and lower damper 522 all adopt viscous dampers.

[0043] The design was further optimized so that both the top plate 2 and the bottom plate 3 are circular structures.

[0044] Further optimization of the scheme resulted in the weight of mass block 31 accounting for 2%-5% of the overall weight of the fan.

[0045] The tuned mass damping vibration reduction device for floating offshore wind turbines provided by this invention has the following working principle:

[0046] The tuned mass damping vibration reduction device for floating offshore wind turbines provided by this invention is installed inside the wind turbine tower 1. The wind turbine tower 1 is made of welded steel plates and has a cylindrical structure. The tuned mass damping vibration reduction device of this invention is installed at the top of the wind turbine tower 1 to maximize the use of the internal space of the wind turbine tower 1, thereby generating the optimal oscillation restoring force and damping force of the mass block 31 inside the tuned mass damping vibration reduction device to achieve the best vibration reduction effect. A top plate 2 is provided at the upper end of the inner side of the wind turbine tower 1, and a bottom plate 3 is provided at the lower end of the inner side of the wind turbine tower 1. The top plate 2 and the bottom plate 3 are welded to the inner wall of the wind turbine tower 1.

[0047] A hydraulic rod 32 and a spring base 33 are installed on the base plate 3. A spring 34 is installed on the spring base 33. Both the hydraulic rod 32 and the spring 34 are connected to the bottom of the mass block 31. The hydraulic rod 32 and the spring 34 jointly bear the weight of the mass block 31, and the tensile strength meets the vibration reduction requirements of the system.

[0048] The mass block 31 is horizontally connected to the damper 4 via a rigid connecting rod 41, and the damper 4 is connected to the wind turbine tower 1 via the rigid connecting rod 41.

[0049] A central hanging column 5 and a side hanging column 51 are installed below the top plate 2. An upper damper 521 and a lower damper 522 are installed on the side wall of the central hanging column 5. A movable pulley 53 is connected to the outside of the lower damper 522. An upper fixed pulley 541 is installed on the side of the side hanging column 51, and a lower fixed pulley 542 is installed at the bottom. The lower end of the rope 6 is connected to the bottom of the mass block 31 through a fixed ring 61. The upper end of the rope 6 is connected to the upper damper 521 through the lower fixed pulley 542, the movable pulley 53 and the upper fixed pulley 541.

[0050] In the initial state, several dampers 4 are arranged in a circular array; the dampers 4 are evenly arranged on the outer wall of the mass block 31, one end of the damper 4 is fixed to the inner wall of the wind turbine tower 1, and the other end is fixed to the outer wall of the vertical mass block 31. The number of dampers 4 is determined according to the design requirements.

[0051] The central column 5 and the mass block 31 are coaxially fixed to the bottom of the top plate 2. The side wall of the central column 5 is fixed with 4 sets of dampers arranged in a circular array. The 4 sets of dampers are divided into upper dampers 521 and lower dampers 522. The number of dampers 4 sets is determined according to the design requirements. The movable pulley 53 is connected to the lower damper 522 and can move in the horizontal direction.

[0052] Several side hanging columns 51 are fixed to the bottom of the top plate 2 in a circular array, and the number is equal to the number of dampers 4 sets. The upper fixed pulley 541 is fixed to the side wall of the side hanging column 51 facing the central hanging column 5, and the top of the upper fixed pulley 541 is flush with the upper viscous damper. The bottom of the upper fixed pulley 541 is flush with the top of the movable pulley 53. The lower fixed pulley 542 is fixed to the bottom of the side hanging column 51, and the top of the lower fixed pulley 542 is flush with the bottom of the movable pulley 53.

[0053] Rope 6 is in a taut state when the fan is stationary, but it does not bear the weight of mass block 31. Rope 6 is arranged in a circular array and its number is equal to the number of side hanging columns 51.

[0054] Dampers 4, 521 (upper damper), and 522 (lower damper) are all viscous dampers. The viscous fluid used in the viscous dampers can be dimethyl silicone oil with a density of 930 kg / m³. 3 ~975kg / m 3 Dynamic viscosity is controlled between 10 and 3 × 10⁻⁶. 5 The viscosity can be adjusted between CST and the relative amount of chain terminator. In addition to dimethyl silicone oil, other types of damping media can also be used. The damping media must meet the following requirements: good viscosity, strong chemical stability, low compressibility, poor temperature sensitivity of liquid viscosity, non-flammable, non-volatile, non-toxic and anti-aging properties.

[0055] This invention relates to a tuned mass damping vibration reduction device for floating offshore wind turbines. The optimal control effect is achieved when the weight of mass block 31 is 2%–5% of the total weight of the wind turbine. Since floating wind turbines are simultaneously affected by multiple environmental loads, such as wind loads and wave loads, and are not limited to a single direction, when subjected to external environmental loads, the wind turbine tower 1 vibrates in both longitudinal and transverse directions. Mass block 31 oscillates back and forth within the wind turbine tower 1, causing friction between the damping medium molecules in the surrounding viscous damper and between the piston and the damping medium. This friction, along with the vibration of the damping medium, causes friction to occur between the damping medium molecules in the surrounding viscous damper. The piston hole generates significant damping, and the resultant force of these actions is the damping force, which can absorb and dissipate structural vibration energy, thereby reducing structural response. At the same time, when the wind turbine is subjected to vibration in the heave direction, the inertia of the mass block 31 and the restoring force of the spring 34 buffer the vibration in the heave direction. When the wind turbine tower vibrates in any direction, the rope 6 drives the damper 4 group through the pulley system to participate in the vibration reduction of the mass block 31, limit the displacement of the damper 4 oscillator, dissipate vibration energy more efficiently, ensure the safety of the tuned mass damping vibration reduction device itself, and improve the adaptability of the floating wind turbine to complex environmental loads.

[0056] The above are merely preferred embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A tuned mass damper vibration reduction device for a floating offshore wind turbine, characterized in that, It comprises a top plate (2) and a bottom plate (3) fixedly installed on the inner wall of a fan tower (1), and a mass block (31) is arranged between the top plate (2) and the bottom plate (3); A plurality of rigid connecting rods (41) are hingedly installed on the inner wall of the fan tower (1) at equal intervals in the circumferential direction, the ends of the rigid connecting rods (41) are hingedly connected with the mass block (31), and dampers (4) are installed on the rigid connecting rods (41); Upper and lower vertical damping mechanisms are respectively installed on the upper and lower ends of the mass block (31), the end of the upper vertical damping mechanism is connected with the top plate (2), and the end of the lower vertical damping mechanism is connected with the bottom plate (3); The lower vertical damping mechanism comprises a plurality of spring bases (33) installed on the bottom plate (3), the top end of each spring base (33) is provided with a spring (34), the top end of the spring (34) is connected with the bottom end of the mass block (31), a plurality of hydraulic rods (32) are hingedly installed on the bottom plate (3), the ends of the hydraulic rods (32) are hingedly connected with the mass block (31), and the hydraulic rods (32) are arranged at equal intervals in the circumferential direction of the mass block (31); The upper vertical damping mechanism comprises a central lifting column (5) installed in the middle of the top plate (2), a plurality of damper (4) groups are arranged at equal intervals in the circumferential direction of the central lifting column (5), a rope (6) is connected to the damper (4) groups, and the end of the rope (6) is fixedly connected with the bottom of the side wall of the mass block (31); A plurality of side lifting columns (51) are fixedly connected to the top plate (2) at equal intervals in the circumferential direction of the central lifting column (5), and the side lifting columns (51) are arranged in one-to-one correspondence with the damper (4) groups; Each damper (4) group comprises an upper damper (521) and a lower damper (522) fixedly installed on the side wall of the central lifting column (5), one end of the lower damper (522) away from the central lifting column (5) is fixedly provided with a movable pulley (53), an upper fixed pulley (541) and a lower fixed pulley (542) are fixedly installed on the side lifting column (51), the movable pulley (53) is located between the upper fixed pulley (541) and the lower fixed pulley (542), and one end of the rope (6) away from the mass block (31) is sequentially wound around the lower fixed pulley (542), the movable pulley (53), the upper fixed pulley (541) and fixedly connected with the upper damper (521).

2. A tuned mass damper device for a floating offshore wind turbine according to claim 1, characterized in that, The top of the lower fixed pulley (542) is flush with the bottom of the movable pulley (53), the top of the movable pulley (53) is flush with the bottom of the upper fixed pulley (541), and the top of the upper fixed pulley (541) is flush with the upper damper (521).

3. A tuned mass damper device for a floating offshore wind turbine according to claim 1, characterized in that, A plurality of fixing rings (61) are fixedly connected to the side wall of the mass block (31) at equal intervals in the circumferential direction, and the fixing rings (61) are arranged one by one in correspondence with the ropes (6), and the lower ends of the ropes (6) are connected to the bottom of the side wall of the mass block (31) through the fixing rings (61).

4. A tuned mass damper device for a floating offshore wind turbine according to claim 3, characterized in that The ropes (6) are in a tension state when the fan is stationary.

5. A tuned mass damper device for a floating offshore wind turbine according to claim 1, characterized in that, The damper (4), the upper damper (521) and the lower damper (522) are all viscous dampers.

6. A tuned mass damper device for a floating offshore wind turbine according to claim 1, characterized in that The top plate (2) and the bottom plate (3) are both circular structures.

7. A tuned mass damper device for a floating offshore wind turbine according to claim 1, characterized in that, The mass block (31) has a weight ratio of 2% to 5% to the overall weight of the fan.

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