Fatigue analysis methods, electronic equipment and media for offshore floating wind turbine foundations

Abstract

The present invention provides a fatigue analysis method, electronic device, and medium for an offshore floating wind turbine foundation. The present invention establishes a multi-load fatigue analysis method based on stress superposition, linearly superimposing the time-series tower bottom load response, time-series mooring response, and time-series wave response of the same working condition to obtain a stress time history curve for the corresponding working condition; performing rain flow counting on the stress time history curve and combining it with the S-N curve to obtain the total fatigue damage of the working condition; and weighting the total fatigue damage of all working conditions within the target service time of the wind turbine foundation to obtain the fatigue damage of all working conditions. The present invention fully considers the influence of each load on an overall scale, matches different loads of the same working condition, is applicable to a variety of complex wind and wave coupling situations, superimposes the stress time series of different loads and performs fatigue processing to obtain the fatigue damage of the wind turbine foundation under all working conditions under multiple load components, thereby improving the accuracy of fatigue damage analysis.

Description

Technical Field

[0001] The present invention belongs to the technical field of offshore wind power, and in particular relates to a fatigue analysis method, electronic equipment and medium for an offshore floating wind turbine foundation. Background Art

[0002] As an innovative technology in the offshore wind power sector, floating wind turbines are showing promising prospects. With the growing demand for clean energy and the urgent need to develop deep-sea wind energy resources, floating wind turbine foundations, with their unique advantages, are becoming a key bridge connecting the abundant wind energy in deep waters with the demand for electricity on land.

[0003] Floating wind turbine foundations involve a variety of complex coupling effects, including interactions between blades, towers, buoys, and anchor cables; coupling between rigid-body motion and elastic deformation; and aerodynamic-structural-hydrodynamic coupling. Fatigue strength verification of floating wind turbine foundations requires comprehensive consideration of these complex coupling effects to ensure safe and reliable operation within the design lifespan.

[0004] Patent application CN11458015A discloses a method for time-domain analysis of local stresses in the foundation of a floating wind turbine structure. This method establishes a multi-body analysis model to obtain the coupled motion state of the floating wind turbine structure. The wave-distributed load on the floating foundation is calculated by replaying the wavefront time history and motion state, combined with a time-domain potential flow solution. The local time-domain stresses of the floating foundation are then obtained through load mapping and solving the governing equations. Probabilistic statistical analysis and Fourier analysis of the time-domain stresses are combined with random signal reconstruction and derivation methods to achieve batch random multiplication of local stresses. Furthermore, extreme value analysis and fatigue damage analysis theory are used to verify the local ultimate strength and fatigue strength of the structure. This method solves local stresses for motion response and fatigue strength analysis, but does not fully consider full-condition, multi-load fatigue analysis. Furthermore, the accuracy of the local stress analysis is relatively low. Summary of the Invention

[0005] The purpose of the present invention is to address the deficiencies of the existing technology and provide a fatigue analysis method, electronic equipment and medium for an offshore floating wind turbine foundation, which considers the influence of various loads on an overall scale and improves the accuracy of fatigue analysis of the wind turbine foundation.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is:

[0007] A fatigue analysis method for an offshore floating wind turbine foundation comprises the following steps:

[0008] Constructing a finite element model of the offshore floating wind turbine foundation according to the structure of the offshore floating wind turbine foundation, wherein the structure of the offshore floating wind turbine foundation includes diagonal bracing, upper connecting beams, columns, lower connecting beams, a nacelle, a tower, and a mooring chain;

[0009] Apply a unit force to the rigid connection between the tower bottom and the column to obtain the tower bottom load unit force response. Multiply the tower bottom load under different working conditions by the tower bottom load unit force response to obtain the time-series tower bottom load response under different working conditions.

[0010] Apply unit force at the mooring chain connection to obtain the mooring unit force response. Multiply the mooring force under different working conditions by the mooring unit force response to obtain the time-series mooring response under different working conditions.

[0011] Based on the random wave spectrum, the Morrison equation is used to calculate the wave loads on the wind turbine foundation. The foundation motion response and hydrodynamic pressure distribution in each regular wave are obtained. Finite element analysis of the wind turbine foundation is performed under various hydrodynamic pressure conditions to obtain the wave response under different conditions.

[0012] Reconstruct the wave response into a time series wave response. The expression of the time series wave response is as follows:

[0013]

[0014]

[0015] The time-series tower bottom load response, time-series mooring response, and time-series wave response of the same working condition are linearly superimposed to obtain the stress time history curve of the corresponding working condition. Rain flow counting is performed on this stress time history curve, and combined with the SN curve, the total fatigue damage of the working condition is obtained.

[0016] The total fatigue damage of all working conditions within the target service time of the wind turbine foundation is weighted and calculated to obtain the fatigue damage of all working conditions. The expression of fatigue damage of all working conditions is as follows:

[0017]

[0018] in, is the time series wave response, is the wave number, is the phase angle, is the amplitude-response transfer function, is the wave frequency, is the frequency interval, is the wave response spectrum, is the standard cosine wave amplitude; D is the fatigue damage under all working conditions, D i is the total fatigue damage of the i-th working condition, m is the number of working conditions, T is the target service time of the wind turbine foundation, T i is the time of the i-th working condition.

[0019] The present invention establishes a multi-load fatigue analysis method based on stress superposition, which fully considers the influence of each load on the overall scale, matches different loads under the same working condition, is applicable to a variety of complex wind and wave coupling conditions, and superimposes the stress time series of different loads and performs fatigue treatment to obtain the full-condition fatigue damage of the wind turbine foundation under multiple load components, thereby improving the accuracy of fatigue damage analysis of the wind turbine foundation.

[0020] Furthermore, the tower bottom load unit force response includes 、 、 、 、 、 Six-DOF unit force response, where 、 、 are the unit forces in the X, Y, and XY directions applied to the rigid connection between the tower bottom and the column, 、 、 It is the unit moment in the X, Y and XY directions applied to the rigid connection between the tower base and the column.

[0021] Furthermore, the mooring unit force response includes different mooring chains 、 、 The three-degree-of-freedom unit force response is 、 、 are the unit forces in the X, Y, and XY directions applied at the j-th mooring chain connection, respectively.

[0022] Furthermore, the wave response includes wave responses in X, Y, and XY directions.

[0023] Based on the same inventive concept, the present invention further provides an electronic device, comprising:

[0024] one or more processors;

[0025] A memory having one or more programs stored thereon, which, when executed by the one or more processors, enables the one or more processors to implement the steps of the offshore floating wind turbine foundation fatigue analysis method.

[0026] Based on the same inventive concept, the present invention further provides a computer-readable storage medium storing a computer program, which implements the steps of the offshore floating wind turbine foundation fatigue analysis method when executed by a processor.

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] The present invention establishes a multi-load fatigue analysis method based on stress superposition, which fully considers the influence of each load on the overall scale, matches different loads under the same working condition, is applicable to a variety of complex wind and wave coupling conditions, superimposes the stress time series of different loads and performs fatigue treatment, and outputs the total fatigue damage of the wind turbine foundation under multiple load components under all working conditions, thereby improving the accuracy of fatigue damage analysis. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 Schematic diagram of the fatigue analysis method of the offshore floating wind turbine foundation of the present invention;

[0030] Figure 2 This is a schematic structural diagram of the offshore floating wind turbine foundation of the present invention;

[0031] Figure 3 A schematic diagram of the finite element model of the offshore floating wind turbine foundation according to the present invention;

[0032] Figure 4 A finite element model of the offshore floating wind turbine foundation of the present invention;

[0033] Figure 5 A wet surface model of the offshore floating wind turbine foundation of the present invention;

[0034] Figure 6 Morrison model of the offshore floating wind turbine foundation of the present invention;

[0035] Figure 7 This is the fatigue condition of the bottom node of the floating wind turbine of the present invention.

[0036] In the figure: 1-wind turbine tower base load, 2-mooring force, 3-water pressure and inertia force, 4-nacelle, 5-tower, 6-diagonal bracing, 7-upper connecting beam, 8-column, 9-lower connecting beam. DETAILED DESCRIPTION

[0037] The present invention will be described in detail below with reference to the following embodiments. It should be noted that the embodiments and features of the embodiments may be combined unless they conflict. For ease of description, the words "upper," "lower," "left," and "right" appearing below merely indicate the directions of upper, lower, left, and right relative to the accompanying drawings and do not limit the structure.

[0038] Example

[0039] like Figure 1This embodiment provides a fatigue analysis method for an offshore floating wind turbine foundation, including a finite element model, a structural calculation combination module, and a calculation execution module. The finite element model is quickly generated by reading the standard design value, and can be used for finite element calculation after further refinement of the structure. The structural calculation combination module calls the finite element program to calculate the unit force response of the wind turbine tower bottom load and the mooring force load, and calculates the wave response spectrum under short-term sea conditions. The calculation execution module serves as a control program to perform working condition management and uniformly call the structural calculation combination module to output sub-item fatigue damage and perform damage superposition.

[0040] The finite element model establishes a mapping relationship between the main scale parameters and the structural layout. The structural calculation module assumes that the entire structure is a linear system, and the responses under the action of each fatigue load component acting on the wind turbine foundation can be linearly superimposed. The fatigue loads acting on the wind turbine foundation at a certain moment include dynamic water pressure caused by waves, radiation water pressure caused by movement, acceleration, static water pressure, loads transmitted by the wind turbine, mooring force and water pressure in the cabin. The responses of these loads are numerically simulated through a series of standard load conditions. The calculation execution module reconstructs the response time series of each condition based on the standard response, and finally superimposes the stress time series and performs fatigue post-processing to obtain the total fatigue damage of the wind turbine foundation under multiple load components.

[0041] According to Figure 2 The floating foundation and mooring system of the floating offshore wind turbine shown in the figure are used to establish a finite element model (such as Figure 4 ), including a nacelle 4, tower 5, diagonal bracing 6, upper connecting beam 7, columns 8, lower connecting beam 9, and mooring chains. Its external parameters, along with the internal plate, rib, beam profile, and span, are explicit parameters. The fatigue analysis method involved in this embodiment considers the effects of tower base load 1, mooring force 2, water pressure, and inertia force 3.

[0042] like Figure 3 This is a flowchart for generating a finite element model. The design parameter table is designed based on the specifications and obtains the dimensional information of the plates, reinforcements, and beams. The Python interface program reads the design values ​​from the design parameter table and overwrites them in the JavaScript program. The program is divided into two major parts: geometry and structure, which are roughly categorized into columns, lower connecting beams, braces, upper connecting beams, and the cabin. It takes about 20 seconds to generate the target structural model, and manual modeling to this depth requires 2 to 3 days. Approximately 800 batch processing command lines are generated, which stipulate approximately 10,000 beam elements and about 100 plate and shell elements.

[0043] The finite element model provides a unified structural model for subsequent finite element calculations. It includes the main structure of the three-column floating wind turbine foundation, including the columns, nacelle, diagonal braces, lower connecting beams, and upper connecting beams, but does not include structural reinforcement structures and connection structures.

[0044] The finite element model is written in JavaScript, and the input design parameters are uniformly read from the standard design table through the Python control program. The control program searches for the corresponding plate, beam, and reinforcement positions and cross-section models, and makes unified modifications.

[0045] The model explicit parameters include the main scale parameters (including the position, size, angle and other information of the diagonal brace, upper connecting beam, lower connecting beam and column, which can describe the Figure 2 The finite element model program automatically generates the model's constraints, including all parameters of the model's external surface shape, wall thickness, beam span, and beam and rib cross-section types. The output finite element model, after supplementing with connections and reinforcements, can be directly used in finite element calculations, providing input for the fatigue calculation execution module.

[0046] The structural calculation module includes three parts: wind turbine tower base load, water pressure and inertia force, and mooring force, which are converted using the following formula:

[0047]

[0048] in, is the structural inertia force, is the structural damping, is the structural restoring force, is the fan aerodynamic force, For water power, is the mooring force. The wind turbine tower bottom load part takes into account and Impact on the fan, water pressure and inertia force are considered and Effect on wind turbine foundation, mooring force part consideration impact.

[0049] The wind turbine tower bottom load part is based on the finite element model. The unit force is applied to the rigid connection between the tower bottom and the column and mapped to the top of the column through the rigid connection of the tower bottom to obtain the unit force response of the tower bottom load. It can be realized by GeniE and Sestra. The unit force response of the tower bottom load includes 、 、 、 、 、 The six-degree-of-freedom unit response, where 、 、 is the unit force in three directions (X, Y, and XY directions) applied at the bottom of the tower, 、 、 is the unit moment applied in three directions at the tower base. A post-processing program uses linear superposition to calculate the tower base load response for different operating conditions. After adding this to the total stress time series, a standard fatigue processing program uses this response, combined with the rain flow counting method and the SN curve, to determine fatigue damage.

[0050] The mooring force part is based on the finite element model. The unit force is applied at the mooring chain connection and mapped to the outer surface of the wind turbine foundation through the beam element. The unit force response at the mooring chain connection is calculated. The unit forces of different mooring chains are numbered separately, such as ( 、 、 、 、 、 ...), where numbers 1 and 2 represent different mooring chains. The post-processing program uses these response results as a basis for linear superposition to obtain the time-series mooring responses for different operating conditions. After superimposing them onto the total stress time series, the standard fatigue processing program uses this response, combined with the rainflow counting method and the SN curve, to determine fatigue damage.

[0051] The water pressure and inertial forces are calculated by applying wave spectrum loads. To avoid repeated consideration of the wind turbine's influence, the tower and nacelle masses are removed from the aforementioned finite element model. The wind turbine foundation inertial forces are represented using a mass-stiffness matrix derived from an integrated calculation (multi-body coupled motion analysis). The transfer function and wave response of the wind turbine foundation are calculated using a random wave spectrum calculation: Given a wind turbine foundation subjected to a regular wave of a given amplitude and frequency, the wave loads acting on the foundation are calculated using a linear approximation based on hydrodynamic theory. Then, a quasi-static analysis of the wind turbine foundation structure is performed using the finite element method to determine the stress and displacement responses (wave response). The ratio of the wave response amplitude to the wave amplitude at the hotspot is taken to determine the transfer function at that frequency. By applying this method to a range of different frequencies, the frequency distribution of the transfer function can be determined. This process can be implemented using methods such as Wadam and Sestra.

[0052] Based on the wave response in different directions ( 、 、 、 、 、 ) reconstructs the time series wave response, where 、 、 is the real part of the principal stress components of the wave response in three directions, 、 、 After being superimposed on the total stress time series, the standard fatigue treatment procedure combines the rain flow counting method with the SN curve to obtain fatigue damage based on this response.

[0053] (1)

[0054] (2)

[0055] in, is the time series wave response, is the wave number, is the phase angle, is the amplitude-response transfer function, is the wave frequency, is the frequency interval, is the wave response spectrum, is the standard cosine wave amplitude.

[0056] The calculation execution module includes a working condition management file, a stress combination program, and a standard fatigue processing program. The working condition management file contains a file for tower force, mooring force, and short-term sea state and duration. The stress combination program centrally manages these working conditions and allows users to specify preset SCF values ​​and SN curves. It then performs stress time series combination. The standard fatigue processing program reads the superimposed stress time series and performs rainflow counting. It then performs fatigue damage calculations based on the SN curves generated by the program.

[0057] The SN curve is a curve that uses the fatigue strength of the standard material specimen as the vertical coordinate and the logarithm of the fatigue life lg N as the horizontal coordinate. It represents the relationship between the fatigue strength and fatigue life of the standard specimen under certain cycle characteristics. It is also called the stress-life curve.

[0058] The selection of SCF value (stress concentration factor) and SN curve can refer to the relevant provisions of the "Technical Guidelines for Fatigue Strength Assessment of Marine Engineering Structures". The reference curves for different floating body positions are different, so the program has preset reference values, which can be selected according to actual conditions (mainly whether it is submerged in seawater).

[0059] Table 1 is a partial mooring force file at time 0s under a certain working condition, which contains the partial forces of a total of 7 mooring chains in three directions, with a calculation time of 600s and a time interval of 0.05s.

[0060] Table 2 shows some short-term sea state files under the same working conditions. The eight components with the lowest frequencies under these sea conditions record information on the frequency, direction, wave height (amplitude), and phase of different components. This embodiment uses the JONSWAP spectrum (random wave spectrum) to describe them.

[0061] Table 3 shows a partial tower force file for the same working condition. The tower force from 0s to 0.15s in this working condition records its components in six degrees of freedom. The calculation time is 600s, and the calculation interval is 0.05s, which is consistent with the mooring force input file.

[0062] Table 1 Mooring force input file

[0063]

[0064] Table 2 Short-term sea state input file

[0065]

[0066] Table 3 Tower bottom load input file

[0067]

[0068] The calculation combination module combines the tower base load unit force response, mooring unit force response, and wave response, reconstructing the response from the input file. This process primarily constructs the transfer function between the wind turbine foundation external load and the unit force and wave responses. The following example illustrates the calculation combination process using a specific grid.

[0069] Since the tower base load is a direct result of the integrated calculation, the mass of the tower and nacelle does not need to be considered when calculating its unit standard response, thus ensuring that the inertia of the wind turbine is not calculated repeatedly. Figure 4 The structural finite element model used for tower base load calculations must maintain the same boundary conditions as the overall model. Unit forces are applied to the rigid links at the tower base to calculate the response. The direct result of this calculation is the tower base load response (Towerstress file). Table 4 below lists the tower base load response for a specific mesh as an example.

[0070] Table 4 Partial tower bottom load response (Pa)

[0071]

[0072] Mooring force and wave spectrum response are calculated by load mapping, combined with Figure 4 The wet surface model is Figure 5 The Morrison model is based on the three-dimensional potential flow theory and the Morrison equation. The wave loads acting on the wet surface unit and the Morrison unit are calculated respectively, and the foundation motion response and hydrodynamic pressure distribution in each regular wave are obtained. The calculated wave loads are then transferred to the finite element model of the wind turbine foundation structure. The structural finite element analysis is performed on each hydrodynamic load condition to obtain the calculated stress of the node structure. The finite element model adopts Figure 4 In the calculation, the mass matrix of the wind turbine foundation needs to be replaced by the result of the integrated calculation to reflect the influence of the inertial force in the motion of the floating body. The direct results of the calculation are the mooring response (Mooringstress file), the static response (staticstress file) and the wave response (wavestress_dir file).

[0073] The wet surface model only represents the outer surface of the underwater portion of the wind turbine foundation, while the Morrison model simplifies the wind turbine foundation structure to beams. Both the wet surface model and the Morrison model include parts of the finite element model.

[0074] Morrison equation: The wave force at each water depth is calculated using the wave particle velocity, acceleration, and column diameter as parameters, and then the wave force on the pile column is obtained by integrating along the column length.

[0075] Table 5 shows some examples of the mooring response (Mooringstress file). This file records the mooring response of a grid under unit force, including the results of seven mooring chains in three degrees of freedom.

[0076] Table 5 Partial mooring response (Pa)

[0077]

[0078] Table 6 shows some examples of static stress response (staticstress file). This file records Figure 4 The stress situation of the finite element model shown is in equilibrium in still water. Under this condition, only the effects of gravity and water pressure are considered.

[0079] Table 6 Static partial response (Pa)

[0080]

[0081] Some examples of wave responses (wavestress_dir files) are shown in Table 7, which records Figure 4 The partial wave response of the finite element model shown here, at specific frequencies, unit wave heights, and specific directions, differs from concentrated loads in that the wave response and load exhibit varying phase differences. Therefore, the wave response file must record this information. Table 7 lists the real and imaginary parts of the stress components in the three directions. The specific frequencies are determined through measured values. In this example, wave components with a combined probability of occurrence greater than 90% are selected to cover the fatigue case calculation.

[0082] Table 7 Wave response (Pa)

[0083]

[0084] Based on the above wave response data, the above formulas (1) and (2) can be used to construct σ in different directions x , σ y , σ xy The wave response stress time series is a two-step process. The first step is to obtain the amplitude of the wave at a specific frequency through the sea state spectrum. In this example, the initial frequency is set to 0.0333333 Hz, and the frequency interval is 1 / 750 Hz.

[0085] In the second step, the stresses in each direction in Table 7 need to be combined and reconstructed into time series signals, and the stress response adopts the standard cosine wave form.

[0086] For the data types in Table 7, the wave response σ x , σ y , σ xy The timing is combined separately. When combining, first interpolate the data in Table 7 for each frequency in Table 2. In this example, Lagrange interpolation, Newton interpolation or Hermite interpolation is used. The response data in Table 7 is actually the amplitude-response transfer function, which can be obtained from the amplitude-response transfer function corresponding to the unit wave height of the frequency in Table 2. , Solving formula (1) yields: The phase angle can be obtained from the data in Table 7, and the time series wave response can be obtained. .

[0087] Solve the wave response σ at the initial frequency x The corresponding phase angle Take as an example, the transfer function obtained after interpolation is processed as follows:

[0088] (3)

[0089] Where, is the wave response σ x The real part of the transfer function, is the wave response σ x The imaginary part of the transfer function.

[0090] The working condition calculation is performed based on the reconstructed time-series tower bottom load response, time-series mooring response, and time-series wave response.

[0091] The calculation program performs calculation combinations for different working conditions at each time step to obtain a complete stress-time history curve for the corresponding working condition. The total fatigue damage under the working condition is then obtained based on the rain flow count and SN curve statistics. The fatigue damage under all working conditions is calculated by weighting the proportion of the target service life of the wind turbine foundation. The fatigue damage under all working conditions is calculated as shown in formula (4):

[0092] (4)

[0093] Where D and D i are respectively the fatigue damage of all working conditions and the total fatigue damage of a certain working condition, m is the total number of working conditions, T and T i They are the basic target service time of the wind turbine and the service time under certain working conditions respectively.

[0094] Take a certain grid as an example. The SN curve of this grid adopts the E curve in air, the stress concentration factor SCF is 1.6, and the plate thickness is 30mm. For each grid that needs to be counted, this setting needs to be automatically generated by the post-processing program. Figure 6 This method uses frequency domain transfer function to reconstruct the time domain signal, which greatly reduces the calculation time.

[0095] Another embodiment of the present invention provides an electronic device, including:

[0096] one or more processors;

[0097] A memory stores one or more programs, which, when executed by one or more processors, enable the one or more processors to implement the steps of the offshore floating wind turbine foundation fatigue analysis method.

[0098] In some implementations, the memory may be a high-speed random access memory (RAM), and may also include a non-volatile memory, such as at least one disk storage.

[0099] In other implementations, the processor may be a central processing unit (CPU), a digital signal processor (DSP), or other general-purpose processors, which are not limited herein.

[0100] Another embodiment of the present invention provides a computer-readable storage medium storing a computer program, which implements the steps of a fatigue analysis method for an offshore floating wind turbine foundation when executed by a processor.

[0101] The contents illustrated in the above embodiments should be understood as these embodiments are only used to more clearly illustrate the present invention, and are not used to limit the scope of the present invention. After reading the present invention, various equivalent modifications of the present invention by those skilled in the art shall fall within the scope defined by the claims attached to this application.

Claims

1. A fatigue analysis method for offshore floating wind turbine foundation, characterized in that: The following processes are included: Constructing a finite element model of the offshore floating wind turbine foundation according to the structure of the offshore floating wind turbine foundation, wherein the structure of the offshore floating wind turbine foundation includes diagonal bracing, upper connecting beams, columns, lower connecting beams, a nacelle, a tower, and a mooring chain; Apply a unit force to the rigid connection between the tower bottom and the column to obtain the tower bottom load unit force response. Multiply the tower bottom load under different working conditions by the tower bottom load unit force response to obtain the time-series tower bottom load response under different working conditions. Apply unit force at the mooring chain connection to obtain the mooring unit force response. Multiply the mooring force under different working conditions by the mooring unit force response to obtain the time-series mooring response under different working conditions. Based on the random wave spectrum, the Morrison equation is used to calculate the wave loads on the wind turbine foundation. The foundation motion response and hydrodynamic pressure distribution in each regular wave are obtained. Finite element analysis of the wind turbine foundation is performed under various hydrodynamic pressure conditions to obtain the wave response under different conditions. Reconstruct the wave response into a time series wave response. The expression of the time series wave response is as follows: ； ； The time-series tower bottom load response, time-series mooring response, and time-series wave response of the same working condition are linearly superimposed to obtain the stress time history curve of the corresponding working condition. Rain flow counting is performed on this stress time history curve, and combined with the SN curve, the total fatigue damage of the working condition is obtained. The total fatigue damage of all working conditions within the target service time of the wind turbine foundation is weighted and calculated to obtain the fatigue damage of all working conditions. The expression of fatigue damage of all working conditions is as follows: ； in, is the time series wave response, is the wave number, is the phase angle, is the amplitude-response transfer function, is the wave frequency, is the frequency interval, is the wave response spectrum, is the standard cosine wave amplitude; D is the fatigue damage under all working conditions, D i is the total fatigue damage of the i-th working condition, m is the number of working conditions, T is the target service time of the wind turbine foundation, T i is the time of the i-th working condition.

2. The offshore floating wind turbine foundation fatigue analysis method according to claim 1, characterized in that: The tower bottom load unit force response includes 、 、 、 、 、 Six-DOF unit force response, where 、 、 are the unit forces in the X, Y, and XY directions applied to the rigid connection between the tower bottom and the column, 、 、 It is the unit moment in the X, Y and XY directions applied to the rigid connection between the tower base and the column.

3. The offshore floating wind turbine foundation fatigue analysis method according to claim 1, characterized in that: The mooring unit force response includes different mooring chain connections 、 、 The three-degree-of-freedom unit force response is 、 、 are the unit forces in the X, Y, and XY directions applied at the j-th mooring chain connection, respectively.

4. The offshore floating wind turbine foundation fatigue analysis method according to claim 1, characterized in that: The wave response includes wave responses in X, Y, and XY directions.

5. An electronic device, characterized in that: include: one or more processors; A memory having one or more programs stored thereon, which, when executed by the one or more processors, enables the one or more processors to implement the steps of the method according to any one of claims 1 to 4.

6. A computer-readable storage medium, characterized in that The computer program is stored therein, and when the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 4 are implemented.

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