Single-pile type offshore wind turbine vibration reduction and toughening control system and control method thereof

Abstract

The invention discloses a single pile type offshore wind turbine damping and toughening control system and method, and the system comprises a plurality of layers of damping and toughening assemblies which are used for providing wind turbine tower support and are symmetrically arranged on each layer along a wind turbine tower, and a control system. The upper end anchoring part, the anchor cable and the lower end anchoring part are sequentially connected, the displacement sensor is connected with the control system and used for detecting a horizontal displacement signal of the fan tower, and the upper end anchoring part comprises an anchoring cylinder, a spring, a damper, a bolt, a gear transmission assembly and a fixing piece. A hole with a clamping groove is reserved in the central axis of the damper so that the anchor cable can penetrate through and be clamped. The control system controls the gear transmission assembly to rotate according to the horizontal displacement signal, the tightness degree of the bolt is adjusted, and tensioning of the damping and toughening assembly is controlled. The problem of structural damage caused by structural micro-vibration in the ocean long-term power environment is solved, the overall natural vibration frequency of the structure under long-term wind wave flow can be effectively regulated and controlled, and the micro-vibration of the offshore wind power structure is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of vibration reduction, and in particular to a single-pile offshore wind turbine vibration reduction and toughening control system and a control method thereof. Background Art

[0002] In recent years, offshore wind power construction and operation have been large in scale and wide in scope. However, under the action of long-term dynamic cyclic loads, the wind turbine structure will produce long-term micro-vibrations during its service life, and its overall structural dynamic response parameters and the control performance of the vibration reduction and toughening device may change, thus failing to achieve the optimal effect; when the total cumulative damage exceeds the maximum range that the structure can withstand, it is very likely to cause safety accidents.

[0003] Therefore, it is urgent to solve the above problems. Summary of the invention

[0004] Purpose of the invention: The first purpose of the present invention is to propose a single-pile offshore wind turbine vibration reduction and toughening control system to solve the problem of structural damage caused by structural micro-vibration in the long-term dynamic environment of the ocean, which can effectively regulate the overall natural frequency of the structure under long-term wind and wave flow and reduce the micro-vibration of the offshore wind power structure.

[0005] A second object of the present invention is to provide a control method for a single-pile offshore wind turbine vibration reduction and toughening control system.

[0006] Technical solution: To achieve the above objectives, the present invention discloses a single-pile offshore wind turbine vibration reduction and toughening control system, comprising several layers of vibration reduction and toughening components and a control system for providing support for the wind turbine tower and each layer being symmetrically arranged along the wind turbine tower, the vibration reduction and toughening components comprising an upper anchor, an anchor cable and a lower anchor connected in sequence, and a displacement sensor connected to the control system and used to detect a horizontal displacement signal of the wind turbine tower, the upper anchor comprising an anchor cylinder, a spring located on a bottom plate inside the anchor cylinder, a damper located inside the anchor cylinder and above the spring, a bolt located inside the anchor cylinder and in contact with the damper at the bottom, a gear transmission assembly for driving the bolt to rotate, and a fixing plate connected to the anchor cylinder and used to ensure that the spring force is transmitted to the wind turbine tower, wherein a hole with a slot is reserved on the central axis of the damper for passing and clamping the anchor cable; the control system controls the rotation of the gear transmission assembly according to the horizontal displacement signal, adjusts the tightness of the bolt, and controls the tensioning of the vibration reduction and toughening assembly.

[0007] Optionally, the control system determines the direction and maximum amplitude of the horizontal displacement |w| according to the horizontal displacement signal. j,max Occurrence location, when the jth layer w j,max When the displacement is greater than the design allowable displacement, the gear transmission component is controlled to rotate. ij , control the tightness of the bolts, squeeze the damper and spring deformation, adjust the clamping position of the anchor cable and the spring deformation, and apply a vertical preload force P to the wind turbine tower.j,new , by asymmetrically regulating the tension P of the j-th layer and the i-th vibration-damping and toughening component ij,new Method to adjust the additional moment M of the wind turbine tower j,new .

[0008] Optionally, the wind turbine tower includes an upper wind turbine tower, a base and a lower wind turbine tower, the upper end of the upper anchor is connected to the upper wind turbine tower or the lower wind turbine tower, and the lower anchor is connected to the seabed surface.

[0009] Optionally, the wind turbine tower includes an upper wind turbine tower, a base and a lower wind turbine tower, the upper end of the upper anchor is connected to the upper wind turbine tower, and the lower anchor is connected to the base.

[0010] Optionally, the gear transmission assembly includes a gear coaxially arranged with the bolt and a conveyor belt for driving the gear to rotate.

[0011] Based on the same inventive concept, the present invention discloses a control method for a single-pile offshore wind turbine vibration reduction and toughening control system, comprising the following steps:

[0012] S1: Real-time monitoring of the horizontal displacement of the wind turbine tower through displacement sensors j and cross-sectional rotation angle φ j , j=,1,2,…m, j is the number of layers of displacement sensors, the direction of horizontal displacement, the number of layers j, horizontal displacement and rotation response spectrum within the time period are obtained, and then the horizontal displacement direction and maximum amplitude |w| are determined according to the response spectrum and wind direction. j,max Occurrence location;

[0013] S2: When the jth layer w j,max When the displacement is greater than the design allowable displacement, the dynamic response balance calculation of the overall structure of the wind turbine tower under the dynamic state is performed to determine the overall natural frequency of the wind turbine tower structure and the pile response, and a control signal is output to drive the gear transmission assembly to rotate;

[0014] S3: According to the control signal, the gear transmission component corresponding to the j-th layer and the i-th vibration reduction and toughening component is regulated to rotate the conveyor belt clockwise, driving the gear to rotate clockwise s ij ; wherein clockwise rotation causes tensioning of the vibration-damping and toughening component;

[0015] S4: At the end of the first regulation, a regulation cycle is set. At each regulation cycle, the monitoring data of the displacement sensor is used to determine the horizontal displacement w. j Is the factor a permanent factor? If yes, then every other adjustment cycle, return to step S1 to re-adjust; if no, after a set period of time, output a control signal to rotate the conveyor belt counterclockwise, driving the gear to rotate counterclockwise for s ij, counterclockwise rotation causes the vibration damping and toughening component to relax, so that the vibration damping and toughening component returns to its initial state until the next regulation cycle, and the regulation is repeated.

[0016] Optionally, the step S2 specifically includes the following steps:

[0017] Step S21: Input the parameters of the wind turbine tower, piles and soil layer, the external loads during the operation phase, and the direction and maximum amplitude of the horizontal displacement |w| obtained in step S1. j,max Occurrence location;

[0018] Step S22: Setting the conveyor belt displacement s ij The value range is 0 to s ij,max , the iteration step is Δs ij,max , the number of iterations is ijs ij,max / Δs ij,max , so as to obtain the current conveyor belt displacement s at each iteration ij , j is the number of vibration reduction and toughening components, i is the number of vibration reduction and toughening components in each layer; set the upper anchor arrangement position of each layer of vibration reduction and toughening components, the distance between the lower anchor point and the pile wall, the number of vibration reduction and toughening components in each layer, and the initial combined tension P j,old ;

[0019] Step S23: Calculate the total tension P of the j-th layer of vibration reduction and toughening components j,new , the additional moment M provided by the j-th layer of vibration reduction and toughening component system j,new and the horizontal external force F provided by the j-th layer of vibration reduction and toughening component system j,new ;

[0020] Step S24: assembling the overall stiffness matrix and the load matrix according to the input parameters of step S21, and determining the boundary conditions at the location of the upper anchor of the vibration reduction and toughening assembly;

[0021] Step S25: Assuming that the load matrix is ​​a zero matrix, the natural frequency and the corresponding vibration mode are calculated using the classical dynamic equation calculation method; according to the load matrix and the natural frequencies of each order, the pile body response of the wind turbine is calculated;

[0022] Step S26: Store the pile body response obtained in step S25 and find the horizontal displacement w new,max Absolute value;

[0023] Step S27: Determine w new,max Is it less than the design allowable displacement? If so, go to step S28. If not, update the current conveyor belt displacement s according to the iterative step size. ij And return to step S22;

[0024] Step S28: Output control signal conveyor belt displacement s ij.

[0025] Optionally, the combined tension P of the j-th layer of vibration reduction and toughening components in step S23 is j,new The feed amount x of the bolts of each vibration damping and toughening component ij and conveyor belt displacement s ij The relationship between them is:

[0026]

[0027] Where: k spring,ij is the elastic modulus of the spring in the j-th layer and the i-th vibration reduction and toughening component; R ij is the outer diameter of the j-th layer and the i-th gear; P j,old is the tension of the j-th layer of vibration reduction and toughening components in the previous iteration;

[0028] The additional moment M provided by the jth layer of vibration damping and toughening components j,new The calculation formula is:

[0029]

[0030] Where: M j,old is the additional moment of the j-th layer of vibration reduction and toughening components in the previous iteration; l ij is the distance from the j-th layer, the i-th vibration reduction and toughening component to the central axis of the wind turbine tower along the horizontal displacement direction;

[0031] The horizontal external force F provided by the j-th layer of vibration-damping and toughening components j,new The calculation formula is:

[0032]

[0033] Where: θ ij is the angle between the jth layer, the ith vibration reduction and toughening component and the z direction, 0≤θ ij <2π; F old The horizontal external force provided by the j-th layer of vibration reduction and toughening component system in the previous iteration;

[0034] K spring,ij The calculation formula is:

[0035]

[0036] Where: k spring,ij is the elastic modulus of the spring in the j-th layer and the i-th vibration reduction and toughening component; k string,ij is the elastic modulus of the anchor cable in the jth layer and the ith vibration reduction and toughening component; c ij is the comprehensive damping coefficient of the damper in the j-th layer and the i-th vibration reduction and toughening component; φ is the shear rotation angle of the pile section; w(z,t) is the horizontal displacement of the pile body; ΔLij The change in length of the cable in the i-th vibration damping and toughening component of the j-th layer during vibration;

[0037] The change in length ΔL of the cable in the i-th vibration damping and toughening component of the j-th layer during vibration ij The calculation formula is:

[0038]

[0039] In the formula: r j is the radius of the rod where the upper anchor of the vibration damping and toughening component of the j-th layer is located; r s is the distance from the lower anchor to the central axis of the rod; υ is the angle formed by the direction of the horizontal displacement w and the anchoring coordinate system of the vibration damping and toughening device.

[0040] Optionally, the dynamic control equation required for assembling the stiffness matrix and the load matrix in step S24 is:

[0041] -L T1 -L T2 ≤z≤-L T2 When

[0042]

[0043] -L T2 <z<0 When

[0044]

[0045] 0<=z<L p When

[0046]

[0047] z>L p When

[0048]

[0049] In the formula: z is the coordinate in the z direction, m w is the unit mass of water inside the wind turbine tower, F(t) and M(t) are the external horizontal load and external moment respectively; ρ T1 is the density of the wind turbine tower; A T1 is the cross-sectional area of the wind turbine tower; κ is the cross-sectional shear coefficient of the variable cross-section Timoshenko beam; G T1 is the stiffness of the wind turbine tower; w is the horizontal displacement of the variable cross-section Timoshenko beam; φ is the rotation angle of the variable cross-section Timoshenko beam; P is the axial force of the variable cross-section Timoshenko beam; E T1 is the elastic modulus of the wind turbine tower; I T1 is the moment of inertia of the wind turbine tower; ρT2 is the density of the connecting segment; A T2 G is the cross-sectional area of ​​the connecting section; T2 is the stiffness of the connecting section; E T2 is the elastic modulus of the connecting section; I T2 is the moment of inertia of the connecting segment; ρ p is the pile density; A p is the cross-sectional area of ​​the pile; G p is the pile body stiffness; E p is the elastic modulus of the pile body; I p is the inertia moment of the pile body; n1 is the mass of the water displaced by the pile body; n2 is the inertia moment caused by the mass of the water displaced by the pile body; n 1,end is the mass of water displaced by the pile body below the pile bottom, n 2,end is the inertia moment caused by the mass of the water displaced by the pile body below the pile bottom; ρ soil is the density of the soil core in the pile; t is the shear stiffness of the soil layer caused by the horizontal displacement of the pile body; t4 is the shear stiffness of the soil layer caused by the rotation between soil layers; k is the compression stiffness of the soil layer caused by the horizontal displacement of the pile body; κ is the section shear coefficient; k1 is the compression stiffness of the soil layer caused by the rotation between soil layers, k3 is the coupling stiffness caused by soil layer compression and interlayer rotation; t end is the shear stiffness of the soil layer caused by the horizontal displacement of the pile body below the pile bottom; 4,end k is the shear stiffness of the soil layer caused by the rotation of the soil layers below the pile bottom; 1,end is the soil compression stiffness caused by the rotation of the soil layers below the pile bottom, k 3,end It is the coupling stiffness caused by soil compression and interlayer rotation below the pile bottom.

[0050] Optionally, the boundary condition at the location of the upper anchor of the vibration reduction and toughening assembly in step S24 is:

[0051]

[0052] Where: A is the cross-sectional area of ​​the structure at the location of the upper anchor of the vibration reduction and toughening assembly; κ is the cross-sectional shear coefficient; G is the stiffness of the structure at the location of the upper anchor of the vibration reduction and toughening assembly; E is the elastic modulus of the structure at the location of the upper anchor of the vibration reduction and toughening assembly; I is the inertia moment of the structure at the location of the upper anchor of the vibration reduction and toughening assembly; P j,new 、M j,new , and F j,new Obtained by step S23.

[0053] Beneficial effects: Compared with the prior art, the present invention has the following significant advantages: the present invention can not only effectively solve the problem of structural damage caused by structural micro-vibration under long-term marine dynamic environment, but also take into account permanent displacement of the structure caused by changes in the foundation under scouring and cyclic loads or transient displacement caused by extreme environment, and accurately control the overall natural frequency of the structure and the degree of reduction of the micro-vibration amplitude under long-term wind and wave flow in real time, and at the same time play a role in correcting deviation and improving the bearing capacity of the foundation to a certain extent. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] Figure 1 It is a schematic diagram of an overall arrangement of the present invention;

[0055] Figure 2 It is a schematic diagram of the dynamic response computational mechanics model of the present invention;

[0056] Figure 3 It is a cross-sectional view of the upper anchor member of the present invention;

[0057] Figure 4 It is a cross-sectional view of the conveyor belt and bolts of the present invention;

[0058] Figure 5 It is a cross-sectional view of the arrangement of the upper anchor member in the present invention;

[0059] Figure 6 It is a flow chart of the control system in the present invention;

[0060] Figure 7 It is another overall schematic diagram of the arrangement of the present invention. DETAILED DESCRIPTION

[0061] The technical solution of the present invention is further described below in conjunction with the accompanying drawings.

[0062] like Figure 1 As shown, the present invention is a single pile offshore wind turbine vibration reduction and toughening control system, including a control system and a plurality of layers of vibration reduction and toughening components 3 symmetrically arranged along the wind turbine tower. The vibration reduction and toughening components 3 provide support for the wind turbine tower. The vibration reduction and toughening components 3 include an upper anchor 31, an anchor cable 32, a lower anchor 33 and a displacement sensor. The displacement sensor is connected to the control system and is used to detect the horizontal displacement signal of the wind turbine tower. Figure 3As shown, the upper anchor 32 includes an anchor tube 316, a spring 314, a damper 313, a bolt 312, a gear transmission assembly 311 and a fixing plate 315. The anchor tube 316 is a structure that is closed on all sides and has a hollow interior. The central axis of the gear 3112 of the gear transmission assembly 311 has a hole reserved for passing the bolt 312. The bottom end of the bolt 312 is in close contact with the top end of the damper 313. The central axis of the damper 313 has a hole with a slot reserved for passing and clamping the anchor cable 32. The bottom end of the damper 313 is fixedly connected in series with the top end of the spring 314. The bottom end of the spring 314 is fixedly connected to the bottom plate of the anchor tube 316. The bottom end of the lower plate of the anchor tube 316 has a hole opened to pass the anchor cable 32. A top view of the positional relationship between the gear transmission assembly 311 and the bolt 312 is shown in FIG. Figure 4 As shown. The gear transmission assembly 311 includes a conveyor belt 3111 and a gear 3112. The conveyor belt 3111 drives the gear 3112 to rotate clockwise and counterclockwise, which is converted into the up and down movement of the bolt 312. The fixing plate 315 is connected to the anchor tube 316 and is used to ensure that the spring force is transmitted to the wind turbine tower. The lower end anchor 33 is a micro pile inserted into the soil. The top of the micro pile is hinged to the anchor cable, and the lower end anchor only plays a pulling and fixing role; the lower end anchor 33 can be constructed according to actual conditions. If the lower end anchor 33 cannot provide sufficient bearing capacity, grouting treatment can also be performed.

[0063] The control system controls the rotation of the gear transmission assembly 311 according to the horizontal displacement signal monitored by the displacement sensor, adjusts the tightness of the bolts, and controls the tension of the vibration reduction and toughening assembly 3. The control system determines the direction of horizontal displacement and the maximum amplitude |w| according to the horizontal displacement signal. j,max Occurrence location, when the jth layer w j,max When the displacement is greater than the design allowable displacement, the rotation displacement s of the control gear transmission component 311 ij , control the tightness of the bolt 312, squeeze the damper 313 and the spring 314 to deform, adjust the clamping position of the anchor cable 32 and the deformation of the spring 314, and apply a vertical preload force P to the wind turbine tower j,new , by asymmetrically regulating the tension P of the j-th layer and the i-th vibration-damping and toughening component 3 ij,new Method to adjust the additional moment M of the wind turbine tower j,new .

[0064] like Figure 1 As shown, the wind turbine tower includes an upper wind turbine tower 1, a support platform and a lower wind turbine tower 2. The upper end of the upper anchor 31 is connected to the upper wind turbine tower or the lower wind turbine tower, and the lower anchor 33 is connected to the seabed surface. Figure 1 As shown in the figure, it can be adjusted according to the site conditions and design requirements. Figure 7As shown, the vibration reduction and toughening assembly is arranged in one layer, the wind turbine tower includes an upper wind turbine tower, a base and a lower wind turbine tower, the upper end of the upper anchor 31 is connected to the upper wind turbine tower, and the lower anchor 33 is connected to the base.

[0065] During the normal use of the structure, for the vibration reduction and toughening component 3, the control system judges and calculates the horizontal displacement signal of the displacement sensor 34, outputs a control signal, controls the transmission belt 3111 in the upper anchor 31 to drive the gear 3112 to rotate clockwise or counterclockwise, controls the tightness of the bolt 312, and thus changes the support effect formed by the vibration reduction and toughening component 3 system according to the environment, such as Figure 2 As shown, the natural frequency and dynamic response of the upper wind turbine tower 1 and the lower wind turbine tower 2 are changed to achieve the purpose of integrated and precise intelligent control of dynamic response.

[0066] like Figure 1 As shown, during the normal use of the structure, a displacement sensor 34 is arranged at the midpoint of the upper anchor 31 to monitor the horizontal displacement w of the upper wind turbine tower 1 and the lower wind turbine tower 2 in real time. j and cross-sectional rotation angle φ j , j = 1, 2, ... m, and obtain the direction, horizontal displacement and angular response spectrum of the horizontal displacement in the time period. In the embodiment, 3 layers of vibration reduction and toughening components are arranged, 8 vibration reduction and toughening components are arranged on each layer, and 3 layers of displacement sensors are arranged at the same time, 8 displacement sensors are arranged on each layer, that is, j = 3, i = 8, as Figure 5 shown.

[0067] The present invention provides a control method for a single-pile offshore wind turbine vibration reduction and toughening control system, comprising the following steps:

[0068] S1: Real-time monitoring of the horizontal displacement w of the wind turbine tower through the displacement sensor 34 j and cross-sectional rotation angle φ j , j=,1,2,…m, j is the number of layers of displacement sensors, the direction of horizontal displacement, the number of layers j, horizontal displacement and rotation response spectrum within the time period are obtained, and then the horizontal displacement direction and maximum amplitude |w| are determined according to the response spectrum and wind direction. j,max Occurrence location;

[0069] S2: When the jth layer w| j,maxWhen it is greater than the design allowable displacement, the design allowable displacement can be set to 0.2m, and the allowable displacement needs to ensure that the power equipment inside the wind turbine cabin is within the maximum allowable horizontal displacement and allowable rotation angle range; the overall structural dynamic response balance calculation of the wind turbine tower under the dynamic state is performed to determine the overall natural frequency of the wind turbine tower structure and the pile body response, and output a control signal to drive the gear transmission component 311 to rotate; the upper wind turbine tower 1 and the lower wind turbine tower 2 of the wind turbine tower both adopt a variable-section Timoshenko beam unit model, and each layer of the vibration reduction and toughening component 3 is simplified to a lateral spring support;

[0070] Step S2 specifically includes the following steps:

[0071] Step S21: Input the parameters of the wind turbine tower, piles and soil layer, the external loads during the operation phase, and the direction and maximum amplitude of the horizontal displacement |w| obtained in step S1. j,max Occurrence location; soil layer parameters such as soil initial stiffness G0, soil Poisson's ratio υ, porosity e, plasticity index I p ; Various parameters of the wind turbine tower are shown in Table 1;

[0072] Table 1 Parameters of wind power structure

[0073] Parameters Belwind <![CDATA[m RNAJ (kg)]]> 130.8 Tower height (m) 53 Diameter of tower bottom(m) 4.3 Minimum diameter of tower top (m) 2.3 Thickness of tower top (mm) 28 Tower bottom thickness 28 Tower elastic modulus (GPa) 210 Tower weight (t) 120 Platform height above mud surface (m) 37 Single pile diameter (m) 5 Single pile wall thickness (mm) 60 Buried depth(mm) 35 Elastic modulus of single pile 210 Single pile density (kg / m3) 7860

[0074] Step S22: Set the conveyor belt 3111 displacement s ij The value range is 0 to s ij,max ,s ij,max Can be set to 0.5m, iteration step is Δs ij,max , the number of iterations is ijs ij,max / Δs ij,max , so as to obtain the current conveyor belt displacement s at each iteration step ij , j is the number of layers of vibration reduction and toughening components 3, i is the number of vibration reduction and toughening components 3 in each layer; set the upper anchor arrangement position of each layer of vibration reduction and toughening components, the distance between the anchor point of the lower anchor and the pile wall, the number of vibration reduction and toughening components in each layer, and the initial combined tension P j,old ; In this embodiment, j = 3, i = 8, Δs ij,max =0.1cm, the number of iteration steps is 12000, and the setting parameters of each layer of vibration reduction and toughening component are shown in Table 2.

[0075] Table 2 Case layout strategy related parameters

[0076] parameter Layer 1 (j=1) Layer 2 (j=2) Layer 3 (j=3) Layout location (m) -45 -30 -15 Distance from lower anchor point to pile wall (m) 6 6 6 Arrangement number i 8 8 8 <![CDATA[Initial tension P j,old (kN)]]> 40 40 40

[0077] Step S23: Calculate the total tension P of the j-th layer of vibration reduction and toughening component 3 j,new , the additional moment M provided by the j-th layer vibration reduction and toughening component 3 system j,newand the horizontal external force F provided by the j-th layer vibration reduction and toughening component 3 system j,new ;

[0078] The total tension P of the jth layer of vibration damping and toughening component 3 j,new The feed amount x of the bolt 312 of each vibration damping and toughening component 3 ij And conveyor belt displacement 3111s ij The relationship between them is:

[0079]

[0080] Where: k spring,ij is the elastic modulus of the spring 314 in the j-th layer and the i-th vibration reduction and toughening component 3; R ij is the outer diameter of the j-th layer, i-th gear 3112; P j,old is the tension of the j-th layer of vibration-damping and toughening component 3 in the previous iteration;

[0081] The additional moment M provided by the jth layer of vibration damping and toughening component 3 j,new The calculation formula is:

[0082]

[0083] Where: M j,old is the additional moment of the j-th layer of vibration reduction and toughening component 3 in the previous iteration; l ij is the distance from the j-th layer, the i-th vibration reduction and toughening component 3 to the central axis of the wind turbine tower along the horizontal displacement direction;

[0084] The horizontal external force F provided by the jth layer of vibration reduction and toughening component 3 j,new The calculation formula is:

[0085]

[0086] Where: θ ij is the angle between the jth layer, the ith vibration reduction and toughening component and the z direction, 0≤θ ij <2π; F old The horizontal external force provided by the j-th layer of vibration reduction and toughening component 3 system in the previous iteration;

[0087] K spring,ij The calculation formula is:

[0088]

[0089] Where: k spring,ij k is the elastic modulus of the spring 314 in the j-th layer and the i-th vibration reduction and toughening component 3; string,ij is the elastic modulus of the anchor cable 32 in the j-th layer and the i-th vibration reduction and toughening component 3; c ijis the comprehensive damping coefficient of the damper 313 in the j-th layer and the i-th vibration damping and toughening component 3; φ is the shear rotation angle of the pile section; w(z,t) is the horizontal displacement of the pile body; ΔL ij is the length change of the cable 32 in the j-th layer and the i-th vibration damping and toughening component 3 during the vibration process;

[0090] The length change ΔL of the cable 32 in the j-th layer and the i-th vibration damping and toughening component 3 during the vibration process ij The calculation formula is:

[0091]

[0092] In the formula: r j is the radius of the rod where the upper anchor of the j-th layer of vibration damping and toughening component 3 is located; r s is the distance from the lower anchor to the central axis of the rod; υ is the angle formed by the direction of the horizontal displacement w and the anchoring coordinate system of the vibration damping device 3;

[0093] Step S24: According to the input parameters in step S21, assemble the overall stiffness matrix and the load matrix. The dynamic control equations required for the assembly of the two matrices are:

[0094] -L T1 -L T2 ≤z≤-L T2 When

[0095]

[0096] -L T2 <z<0 When

[0097]

[0098] 0<=z<L p When

[0099]

[0100] z>L p When

[0101]

[0102] In the formula: z is the coordinate in the z direction, m w is the unit mass of the water inside the wind turbine tower; F(t) and M(t) are the external horizontal load and external moment respectively; ρ T1 is the density of the wind turbine tower; A T1 is the cross-sectional area of the wind turbine tower; κ is the cross-section shear coefficient of the variable cross-section Timoshenko beam; G T1is the wind turbine tower stiffness; w is the horizontal displacement of the variable-section Timoshenko beam; φ is the rotation angle of the variable-section Timoshenko beam; P is the axial force of the variable-section Timoshenko beam; E T1 is the elastic modulus of the wind turbine tower; I T1 is the moment of inertia of the wind turbine tower; T2 is the density of the connecting segment; A T2 G is the cross-sectional area of ​​the connecting section; T2 is the stiffness of the connecting section; E T2 is the elastic modulus of the connecting section; I T2 is the moment of inertia of the connecting segment; ρ p is the pile density; A p is the cross-sectional area of ​​the pile; G p is the pile body stiffness; E p is the elastic modulus of the pile body; I p is the inertia moment of the pile body; n1 is the mass of the water displaced by the pile body; n2 is the inertia moment caused by the mass of the water displaced by the pile body; n 1,end is the mass of water displaced by the pile body below the pile bottom, n 2,end is the inertia moment caused by the mass of the water displaced by the pile body below the pile bottom; ρ soil is the density of the soil core in the pile; t is the shear stiffness of the soil layer caused by the horizontal displacement of the pile body; t4 is the shear stiffness of the soil layer caused by the rotation between soil layers; k is the compression stiffness of the soil layer caused by the horizontal displacement of the pile body; κ is the section shear coefficient; k1 is the compression stiffness of the soil layer caused by the rotation between soil layers, k3 is the coupling stiffness caused by soil layer compression and interlayer rotation; t end is the shear stiffness of the soil layer caused by the horizontal displacement of the pile body below the pile bottom; 4,end k is the shear stiffness of the soil layer caused by the rotation of the soil layers below the pile bottom; 1,end is the soil compression stiffness caused by the rotation of the soil layers below the pile bottom, k 3,end It is the coupling stiffness caused by soil compression and interlayer rotation below the pile bottom.

[0103] Boundary conditions at the location of the upper anchor of the vibration reduction and toughening component 3:

[0104]

[0105] Where: A is the cross-sectional area of ​​the structure at the location of the upper anchor of the vibration reduction and toughening component 3; κ is the cross-sectional shear coefficient; G is the stiffness of the structure at the location of the upper anchor of the vibration reduction and toughening component 3; E is the elastic modulus of the structure at the location of the upper anchor of the vibration reduction and toughening component 3; I is the inertia moment of the structure at the location of the upper anchor of the vibration reduction and toughening component 3; P j,new 、M j,new , and F j,newObtained by step S23; wherein, the assembly process of the structural overall stiffness matrix and the load matrix is ​​within the scope of the published dynamic theory;

[0106] Step S25: Assuming that the load matrix is ​​a zero matrix, the natural frequency and the corresponding vibration mode are calculated using the classical dynamic equation calculation method; according to the load matrix and each order of natural frequency in step S24, the pile body response of the wind turbine is calculated;

[0107] Step S26: Store the pile body response obtained in step S25 and find the horizontal displacement w new,max Absolute value;

[0108] Step S27: Determine w new,max Is it less than the design allowable displacement? If so, proceed to step S28. If not, update the current conveyor belt 3111 displacement s according to the iteration step. ij And return to step S22;

[0109] Step S28: Output control signal conveyor belt 3111 displacement s ij Drive the gear transmission assembly 311 to rotate;

[0110] S3: According to the control signal, the gear transmission component 311 corresponding to the j-th layer and the i-th vibration reduction and toughening component 3 rotates the conveyor belt 3111 clockwise, driving the gear 3112 to rotate clockwise for s. ij ; wherein clockwise rotation causes the vibration damping and toughening component 3 to be tensioned; as shown in Table 3, in this embodiment, it is recommended to adjust the vibration damping and toughening component 3 according to the PID control method. The purpose of using the PID control method is to improve the system stability of the vibration damping and toughening component 3 during the adjustment process and to suppress excessive deviations in the transition process.

[0111] Table 3 s corresponding to each layer of vibration reduction and toughening device ij

[0112]

[0113]

[0114] S4: At the end of the first regulation, set the regulation cycle, which can be set to 10 days. At each regulation cycle, the monitoring data of the displacement sensor is used to determine the horizontal displacement w j Is the factor a permanent factor? If yes, then every other adjustment cycle, return to step S1 to re-adjust; if no, then after a set period of time, such as 24 hours, output a control signal to rotate the conveyor belt 3111 counterclockwise, driving the gear 3112 to rotate counterclockwise for s ij , counterclockwise rotation causes the vibration damping and toughening component 3 to relax, so that the vibration damping and toughening component 3 returns to its initial state until the next regulation cycle, and the regulation is repeated.

[0115] In this embodiment, personnel judge the horizontal displacement w by monitoring data. j The factor is not a permanent factor, so 24 hours after the adjustment is completed, the conveyor belt 3111 in the gear transmission component 311 corresponding to the j-th layer and the i-th vibration reduction and toughening component 3 is regulated to rotate counterclockwise, driving the gear 3112 to rotate counterclockwise s ij , so that the vibration reduction and toughening component 3 is restored to its initial state, and then ends, until 9 days later, the personnel are prompted again to judge the cause of the horizontal displacement w through the monitoring data j Whether the factor is a permanent factor.

[0116] The axial tension force applied to each layer is 200kN, and the tension P of each layer of vibration reduction and toughening component is ij The parameters are shown in Table 4. Through calculation, the solution provided by this embodiment has the following characteristics: the direction of horizontal displacement and the maximum amplitude |w| j,max The reduction is greater than 10%, and the natural frequency is increased by more than 6%, which effectively reduces the micro-vibration of offshore wind power structures. At the same time, it plays a role in correcting deviations and improving the bearing capacity of the foundation to a certain extent.

[0117] Table 4 Tension P of each layer of vibration reduction and toughening device ij

[0118]

[0119]

Claims

1. A single-pile offshore wind turbine vibration reduction and toughening control system, characterized in that: The invention comprises a plurality of layers of vibration reduction and toughening components (3) for providing support for a wind turbine tower and each layer is symmetrically arranged along the wind turbine tower, and a control system. The vibration reduction and toughening components (3) comprise an upper anchor (31), an anchor cable (32) and a lower anchor (33) connected in sequence, and a displacement sensor (34) connected to the control system and used for detecting a horizontal displacement signal of the wind turbine tower. The upper anchor (32) comprises an anchor cylinder (316), a spring (314) located on a bottom plate inside the anchor cylinder, and a damper (313) located inside the anchor cylinder and above the spring. ), a bolt (312) located in the anchor cylinder and having its bottom end in contact with the damper, a gear transmission assembly (311) for driving the bolt (312) to rotate, and a fixing plate (315) connected to the anchor cylinder (316) and used to ensure that the spring force is transmitted to the wind turbine tower, wherein a hole with a slot is reserved on the central axis of the damper (321) for passing and clamping the anchor cable (32); the control system controls the rotation of the gear transmission assembly (311) according to the horizontal displacement signal, adjusts the tightness of the bolt, and controls the tension of the vibration reduction and toughening assembly (3).

2. A single pile offshore wind turbine vibration reduction and toughening control system according to claim 1, characterized in that: The control system determines the direction of horizontal displacement and the maximum amplitude |w| according to the horizontal displacement signal j,max Occurrence location, when the jth layer w j,max When the displacement is greater than the design allowable displacement, the rotation displacement s of the control gear transmission component (311) ij , control the tightness of the bolt (312), squeeze the damper (313) and the spring (314) to deform, adjust the clamping position of the anchor cable (32) and the deformation of the spring (314), and apply a vertical preload force P to the wind turbine tower. j,new , by asymmetrically regulating the tension P of the j-th layer and the i-th vibration-damping and toughening component (3) ij,new Method to adjust the additional torque M of the wind turbine tower j,new .

3. A single pile offshore wind turbine vibration reduction and toughening control system according to claim 1, characterized in that: The wind turbine tower comprises an upper wind turbine tower, a support platform and a lower wind turbine tower. The upper end of the upper anchor (31) is connected to the upper wind turbine tower or the lower wind turbine tower, and the lower anchor (33) is connected to the seabed surface.

4. A single pile offshore wind turbine vibration reduction and toughening control system according to claim 1, characterized in that: The wind turbine tower comprises an upper wind turbine tower, a support platform and a lower wind turbine tower. The upper end of the upper anchor (31) is connected to the upper wind turbine tower, and the lower anchor (33) is connected to the support platform.

5. A single pile offshore wind turbine vibration reduction and toughening control system according to claim 1, characterized in that: The gear transmission assembly (311) comprises a gear (3112) coaxially arranged with the bolt (312) and a conveyor belt (3111) for driving the gear to rotate.

6. A control method for a monopile offshore wind turbine vibration reduction and toughening control system according to claims 1 to 5, characterized in that: The steps include: S1: Real-time monitoring of the horizontal displacement w of the wind turbine tower through the displacement sensor (34) j and cross-sectional rotation angle φ j , j=,1,2,…m, j is the number of layers of displacement sensors, the direction of horizontal displacement, the number of layers j, horizontal displacement and rotation response spectrum within the time period are obtained, and then the horizontal displacement direction and maximum amplitude |w| are determined according to the response spectrum and wind direction. j,max Occurrence location; S2: When the jth layer w j,max When the displacement is greater than the design allowable displacement, a dynamic response balance calculation of the overall structure of the wind turbine tower under the dynamic state is performed to determine the overall natural frequency of the wind turbine tower structure and the pile response, and a control signal is output to drive the gear transmission component (311) to rotate; S3: According to the control signal, the gear transmission component (311) corresponding to the j-th layer and the i-th vibration reduction and toughening component (3) is regulated to rotate the conveyor belt (3111) clockwise, thereby driving the gear (3112) to rotate clockwise by s ij ; wherein clockwise rotation causes the vibration damping and toughening component (3) to be tensioned; S4: At the end of the first regulation, a regulation cycle is set. At each regulation cycle, the monitoring data of the displacement sensor is used to determine the horizontal displacement w. j Is the factor a permanent factor? If yes, then every other adjustment cycle, return to step S1 to re-adjust; if no, after a set period of time, output a control signal to rotate the conveyor belt (3111) counterclockwise, driving the gear (3112) to rotate counterclockwise for s ij , counterclockwise rotation causes the vibration-damping and toughening component (3) to relax, so that the vibration-damping and toughening component (3) returns to its initial state until the next regulation cycle, and the regulation is repeated.

7. A control method for a monopile offshore wind turbine vibration reduction and toughening control system according to claim 6, characterized in that: The step S2 specifically includes the following steps: Step S21: Input the parameters of the wind turbine tower, piles and soil layer, the external loads during the operation phase, and the direction and maximum amplitude of the horizontal displacement |w| obtained in step S1. j,max Occurrence location; Step S22: Set the conveyor belt (3111) displacement s ij The value range is 0 to s ij,max , the iteration step is Δs ij,max , the number of iterations is ijs ij,max / Δs ij,max , thereby obtaining the current conveyor belt (3111) displacement s at each iteration step ij , j is the number of layers of vibration damping and toughening components (3), i is the number of vibration damping and toughening components (3) in each layer; the upper anchor arrangement position of each layer of vibration damping and toughening components, the distance between the anchor point of the lower anchor and the pile wall, the number of vibration damping and toughening components in each layer and the initial combined tension P are set j,old ; Step S23: Calculate the resultant tension P of the j-th layer of vibration-damping and toughening component (3) j,new , the additional moment M provided by the j-th layer of vibration reduction and toughening component (3) system j,new and the horizontal external force F provided by the j-th layer of vibration reduction and toughening component (3) system j,new ; Step S24: assembling the overall stiffness matrix and the load matrix according to the input parameters of step S21, and determining the boundary conditions at the location of the upper anchor of the vibration reduction and toughening component (3); Step S25: Assuming that the load matrix is ​​a zero matrix, the natural frequency and the corresponding vibration mode are calculated using the classical dynamic equation calculation method; according to the load matrix and the natural frequencies of each order, the pile body response of the wind turbine is calculated; Step S26: Store the pile body response obtained in step S25 and find the horizontal displacement w new,max Absolute value; Step S27: Determine w new,max Is it less than the design allowable displacement? If so, go to step S28. If not, update the current conveyor belt (3111) displacement s according to the iteration step. ij And return to step S22; Step S28: Output control signal conveyor belt (3111) displacement s ij .

8. A control method for a monopile offshore wind turbine vibration reduction and toughening control system according to claim 7, characterized in that: The resultant tension P of the j-th layer of the vibration-damping and toughening component (3) in step S23 is j,new The feed amount x of the bolt (312) of each vibration damping and toughening assembly (3) ij and conveyor belt (3111) displacement s ij The relationship between them is: Where: k spring,ij is the elastic modulus of the spring (314) in the j-th layer and the i-th vibration reduction and toughening component (3); R ij is the outer diameter of the j-th layer, i-th gear (3112); P j,old is the tension of the j-th layer of vibration-damping and toughening component (3) in the previous iteration; The additional moment M provided by the jth layer of vibration damping and toughening component (3) j,new The calculation formula is: Where: M j,old is the additional moment of the j-th layer of vibration reduction and toughening component (3) in the previous iteration; l ij is the distance from the j-th layer, the i-th vibration reduction and toughening component (3) to the central axis of the wind turbine tower along the horizontal displacement direction; The horizontal external force F provided by the j-th layer of vibration reduction and toughening component (3) j,new The calculation formula is: Where: θ ij is the angle between the jth layer, the ith vibration reduction and toughening component and the z direction, 0≤θ ij <2π; F old The horizontal external force provided by the j-th layer of vibration reduction and toughening component (3) system in the previous iteration; K spring,ij The calculation formula is: Where: k spring,ij k is the elastic modulus of the spring (314) in the j-th layer and the i-th vibration reduction and toughening component (3); string,ij is the elastic modulus of the anchor cable (32) in the j-th layer and the i-th vibration reduction and toughening component (3); c ij is the comprehensive damping coefficient of the damper (313) in the j-th layer and the i-th vibration reduction and toughening component (3); φ is the shear rotation angle of the pile section; w(z,t) is the horizontal displacement of the pile; ΔL ij is the length change of the anchor cable (32) in the j-th layer and the i-th vibration reduction and toughening component (3) during the vibration process; The length change ΔL of the anchor cable (32) in the j-th layer and the i-th vibration reduction and toughening component (3) during the vibration process ij The calculation formula is: Where: r j r is the radius of the rod where the upper anchor of the j-th layer vibration reduction and toughening component (3) is located; s is the distance between the lower anchor and the central axis of the rod; υ is the angle formed by the direction of the horizontal displacement w and the anchor coordinate system of the vibration reduction and toughening device (3).

9. A control method for a monopile offshore wind turbine vibration reduction and toughening control system according to claim 7, characterized in that: The dynamic control equations used for assembling the stiffness matrix and the load matrix in step S24 are: -L T1 -L T2 ≤z≤-L T2 hour -L T2 when z < 0 0<=z <L p hour z>L p hour Where: z is the coordinate in the z direction, m w is the unit mass of water inside the wind turbine tower, F(t) and M(t) are the external horizontal load and external moment, respectively; ρ T1 is the wind turbine tower density; A T1 is the cross-sectional area of ​​the wind turbine tower; κ is the cross-sectional shear coefficient of the Timoshenko beam with variable cross-section; G T1 is the wind turbine tower stiffness; w is the horizontal displacement of the variable-section Timoshenko beam; φ is the rotation angle of the variable-section Timoshenko beam; P is the axial force of the variable cross-section Timoshenko beam; E T1 is the elastic modulus of the wind turbine tower; I T1 is the moment of inertia of the wind turbine tower; T2 is the density of the connecting segment; A T2 G is the cross-sectional area of ​​the connecting section; T2 is the stiffness of the connecting section; E T2 is the elastic modulus of the connecting section; I T2 is the moment of inertia of the connecting segment; ρ p is the pile density; A p is the cross-sectional area of ​​the pile; G p is the pile stiffness; E p is the elastic modulus of the pile body; I p is the inertia moment of the pile body; n1 is the mass of the water displaced by the pile body; n2 is the inertia moment caused by the mass of the water displaced by the pile body; n 1,end is the mass of water displaced by the pile body below the pile bottom, n 2,end is the inertia moment caused by the mass of the water displaced by the pile body below the pile bottom; ρ soil is the density of the soil core in the pile; t is the soil shear stiffness caused by the horizontal displacement of the pile body; t4 is the soil shear stiffness caused by the rotation between soil layers; k is the soil compression stiffness caused by the horizontal displacement of the pile body; κ is the section shear coefficient; k1 is the soil compression stiffness caused by the rotation between soil layers, k3 is the coupling stiffness caused by soil compression and interlayer rotation; t end is the shear stiffness of the soil layer caused by the horizontal displacement of the pile body below the pile bottom; 4,end k is the shear stiffness of the soil layer caused by the rotation of the soil layers below the pile bottom; 1,end is the soil compression stiffness caused by the rotation of the soil layers below the pile bottom, k 3,end It is the coupling stiffness caused by soil compression and interlayer rotation below the pile bottom.

10. A control method for a monopile offshore wind turbine vibration reduction and toughening control system according to claim 7, characterized in that: The boundary conditions at the location of the upper anchor of the vibration reduction and toughening component (3) in step S24 are: Wherein: A is the cross-sectional area of ​​the structure at the location of the upper anchor of the vibration damping and toughening component (3); κ is the cross-sectional shear coefficient; G is the stiffness of the structure at the location of the upper anchor of the vibration damping and toughening component (3); E is the elastic modulus of the structure at the location of the upper anchor of the vibration damping and toughening component (3); I is the moment of inertia of the structure at the location of the upper anchor of the vibration damping and toughening component (3); P j,new 、M j,new , and F j,new Obtained by step S23.

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