Damping cable vibration reduction device of offshore floating type wind turbine

Abstract

The utility model discloses a damping cable vibration reduction device of an offshore floating type wind turbine. The damping cable vibration reduction device comprises a floating platform, a tower, a spring damping device and a mooring cable. The floating platform comprises three floating barrels and a tower barrel; every two adjacent buoys are connected through a connecting rod I; each buoy is connected with the tower drum through a connecting rod II; a fixed pulley rod and a mooring rope are mounted at the bottom of each buoy, and a fixed pulley is mounted at the lower end of each fixed pulley rod; the tower frame is installed in the tower drum, three flexible cables I are connected to the tower frame, the lower ends of the flexible cables I are connected with the upper ends of the spring damping devices, and the lower ends of the spring damping devices are connected with the corresponding mooring cables through flexible cables II. The damper is simple in structure, the energy consumption characteristic of the damper is utilized, vibration of a wind turbine platform is effectively reduced, the stability of a wind turbine is improved, and the service life of the wind turbine is prolonged. The damping device is high in response speed and capable of rapidly providing a damping effect when the wind turbine platform rotates.

Description

Technical Field

[0001] The utility model belongs to the technical field of offshore wind turbines, and in particular relates to a damping cable vibration reduction device for an offshore floating wind turbine. Background Art

[0002] Environmental pollution caused by traditional petrochemical energy is becoming more and more serious. Against this background, the use of wind energy has developed rapidly around the world. The sea has the advantages of high wind speed, short calm period, no land resources and no need to consider noise pollution. Therefore, offshore wind turbines are gradually developing in the deep sea. Since the foundation of the floating wind turbine platform is not fixed, the floating wind turbine will cause the platform to sway under the combined action of wind, wave and flow loads. Compared with onshore wind turbines, the swaying of floating wind turbines significantly increases the dynamic response and deformation of key components such as blades, towers, and generator shafts, and may even cause safety accidents such as fatigue failure, tilting or capsizing.

[0003] At present, the vibration reduction of offshore floating wind turbine platforms is mainly tuned mass damper vibration reduction, which relies on setting a mass block inside the wind turbine and supporting the mass block with springs and dampers to form a power system, namely TMD. When its frequency is consistent with the frequency of wind turbine vibration, the TMD will vibrate greatly. The periodic power of TMD on the wind turbine is in reverse phase with the power of external load on the wind turbine, so as to reduce the vibration of floating wind turbine. However, since floating wind turbines are subject to multiple loads of wind, waves and currents in the deep sea, the structure may have multi-modal and low-frequency responses. Since TMD is very sensitive to structural frequency, the vibration control effect of floating wind turbines is limited.

[0004] The vibration control effect of the damping cable and energy dissipation damper vibration reduction structure is good. The damping cable and energy dissipation damper (including various fluid dampers, friction dampers, rubber dampers, metal dampers, eddy current dampers and other energy dissipation elements) vibration reduction structure is easily used to suppress the vibration of the land wind turbine tower. However, since the floating wind turbine is located in the deep sea environment, the damping cable connecting the floating platform and the seabed is easily vibrated by the ocean current, and its application is limited. Therefore, the energy dissipation damper cannot be used for vibration reduction of floating offshore wind turbines at present. Summary of the invention

[0005] In order to solve the above technical problems, the utility model provides a damping cable vibration reduction device for an offshore floating wind turbine which has a simple structure, good vibration control effect and can improve the stability and service life of the wind turbine.

[0006] The technical solution adopted by the utility model is: a damping cable vibration reduction device for an offshore floating wind turbine, comprising a floating platform, a tower, a spring damping device and a mooring cable; the floating platform is connected to the seabed through three mooring cables;

[0007] The floating platform includes three buoys and a tower; two adjacent buoys are connected by a connecting rod I to form an equilateral triangle; each buoy is connected to the tower through a connecting rod II; the three buoys are respectively located at the three vertices of the equilateral triangle, the tower is located at the center of the equilateral triangle, and the axes of the buoys and the tower are both vertically arranged; a fixed pulley rod and a mooring cable are installed at the bottom of each buoy, and a fixed pulley is installed at the lower end of the fixed pulley rod; the tower is installed in the tower, and three flexible cables I are connected to the tower, the lower end of the flexible cable I is connected to the upper end of the spring damping device, the lower end of the spring damping device is connected to the upper end of the flexible cable II, and the lower end of the flexible cable II bypasses the corresponding fixed pulley and is connected to the corresponding mooring cable.

[0008] Furthermore, the connecting rod I is located at the top of the buoy; the connecting rod II is located at the bottom of the buoy, and the connecting rod I and the connecting rod II are arranged horizontally.

[0009] Furthermore, a connecting rod III is provided between each buoy and the tower, and the connecting rod III and the connecting rod II connected to the same buoy are located in the same vertical plane, and an angle is formed between the connecting rod III and the connecting rod II.

[0010] Furthermore, the spring damping device includes a damper and a spring connected in parallel between the flexible cable I and the flexible cable II.

[0011] Furthermore, a reinforcing rod is provided between the fixed pulley rod and the bottom of the tower.

[0012] Compared with the prior art, the beneficial effects of the utility model are:

[0013] The utility model has a simple structure, utilizes the energy consumption characteristics of the damper, effectively reduces the vibration of the wind turbine platform, and improves the stability and service life of the wind turbine. The utility model adopts damping rope vibration reduction, has a fast response speed, and can quickly provide a vibration reduction effect when the wind turbine platform rotates. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is the front view of the utility model.

[0015] Figure 2 It is a top view of the utility model after the wind turbine is removed.

[0016] Figure 3 It is a structural diagram of the utility model when vibrating.

[0017] Figure 4 yes Figure 3 Enlarged view of point I in FIG. DETAILED DESCRIPTION

[0018] The utility model is further described below in conjunction with the accompanying drawings.

[0019] like Figure 1-2As shown, the utility model comprises a floating platform, a tower 8, a spring damping device and a mooring cable 9; the tower 8 is installed on the floating platform, and the floating platform is connected to the seabed through three mooring cables 9; the three mooring cables 9 are evenly arranged along the circumferential direction. The wind turbine 7 is installed on the top of the tower 8.

[0020] The floating platform includes three buoys 10 and a tower 12; two adjacent buoys 10 are connected by a connecting rod I11 to form an equilateral triangle; each buoy 10 is connected to the tower 12 by a connecting rod II13. The three buoys 10 are respectively located at the three vertices of the equilateral triangle, the tower 12 is located at the center of the equilateral triangle, and the axes of the buoys 10 and the tower 12 are both arranged vertically; a fixed pulley rod 1 and a mooring cable 9 are installed at the bottom of each buoy 10, and a fixed pulley 5 is installed at the lower end of the fixed pulley rod 1; a reinforcing rod 6 is arranged between the fixed pulley rod 1 and the bottom of the tower 12. The connecting rod I11 is located at the top of the buoy; the connecting rod II13 is located at the bottom of the buoy, and the connecting rods I11 and II13 are arranged horizontally. A connecting rod III14 is also arranged between each buoy 10 and the tower 12, and the connecting rod III14 connected to the same buoy and the connecting rod II13 are located in the same vertical plane, and an angle is formed between the connecting rod III and the connecting rod II13.

[0021] The tower 8 is installed in the tower 12, and three flexible cables I are connected to the tower 8, and the three flexible cables I are respectively arranged corresponding to the three fixed pulleys. The lower end of the flexible cable I is connected to the upper end of the spring damping device, and the lower end of the spring damping device is connected to the upper end of the flexible cable II2, and the lower end of the flexible cable II2 bypasses the corresponding fixed pulley 5 and is connected to the corresponding mooring cable 9. The spring damping device includes a damper 4 and a spring 3 connected in parallel between the flexible cable I and the flexible cable II2.

[0022] The working principle of the utility model is as follows:

[0023] like Figure 3 As shown in the figure, the working principle is explained by taking the working condition when the floating platform rotates counterclockwise as an example. Under normal circumstances, a single mooring cable 9 bears hundreds of tons of load, and the cable force of the flexible cable I and the flexible cable II2 is less than 1 ton. The influence of the tension change of the flexible cable I and the flexible cable II2 on the deformation of the mooring cable can be ignored. When the floating wind turbine platform rotates counterclockwise, assuming that its rotation angle is △θ, as shown in Figure 4As shown, when the floating wind turbine rotates, the dotted line in the figure changes to the solid line, and the length of the BC section cable Ⅱ2 decreases by △θ×AB. Point A is the upper end of the fixed pulley rod 1, and point B is the center point of the fixed pulley; AB is the distance between point A and point B, point C is the connection point between the cable Ⅱ2 and the mooring cable 9, point B1 is the position to which point B moves after the floating platform rotates, and point C1 is the position to which point C moves after the floating platform rotates. Since the cables I and II2 have large stiffness and small deformation, the pre-tensioned reset spring shrinks to ensure that the total length of the cables I and II2 remains basically unchanged, and at the same time, the damper 4 is driven to have a compression stroke of △θ×AB, and the damper 4 does negative work on the floating platform, consuming the mechanical energy of the floating platform. Similarly, the left cable I, cable II2, and spring 3 are stretched, and the spring 3 and damper 4 will be stretched quickly, and the damper 4 also consumes the mechanical energy of the system.

Claims

1. A damping cable vibration reduction device for an offshore floating wind turbine, comprising a floating platform, a tower, a spring damping device and a mooring cable; the floating platform is connected to the seabed through three mooring cables; Its characteristics are: The floating platform includes three buoys and a tower; two adjacent buoys are connected by a connecting rod I to form an equilateral triangle; each buoy is connected to the tower through a connecting rod II; the three buoys are respectively located at the three vertices of the equilateral triangle, the tower is located at the center of the equilateral triangle, and the axes of the buoys and the tower are both vertically arranged; a fixed pulley rod and a mooring cable are installed at the bottom of each buoy, and a fixed pulley is installed at the lower end of the fixed pulley rod; the tower is installed in the tower, and three flexible cables I are connected to the tower, the lower end of the flexible cable I is connected to the upper end of the spring damping device, the lower end of the spring damping device is connected to the upper end of the flexible cable II, and the lower end of the flexible cable II bypasses the corresponding fixed pulley and is connected to the corresponding mooring cable.

2. The damping cable vibration reduction device for an offshore floating wind turbine according to claim 1 is characterized in that: The connecting rod I is located at the top of the buoy; the connecting rod II is located at the bottom of the buoy, and the connecting rod I and the connecting rod II are arranged horizontally.

3. The damping cable vibration reduction device for an offshore floating wind turbine according to claim 1 is characterized in that: A connecting rod III is also provided between each buoy and the tower. The connecting rod III and the connecting rod II connected to the same buoy are located in the same vertical plane, and an angle is formed between the connecting rod III and the connecting rod II.

4. The damping cable vibration reduction device for an offshore floating wind turbine according to claim 1 is characterized in that: The spring damping device comprises a damper and a spring which are connected in parallel between the flexible cable I and the flexible cable II.

5. The damping cable vibration reduction device for an offshore floating wind turbine according to claim 1 is characterized in that: A reinforcing rod is arranged between the fixed pulley rod and the bottom of the tower.

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