Wind turbine blade full-coupled dynamic response refined analysis method

Abstract

This invention discloses a refined analysis method for the fully coupled dynamic response of wind turbine blades. Addressing the shortcomings of existing blade design and analysis methods in industry and academia, which incompletely consider loads during load simulation and neglect time-varying blade motion in refined analysis, this invention employs a fully coupled method that simultaneously considers the influences of aerodynamics, hydrodynamics, structural dynamics, electromechanical servo control dynamics, and soil-structure interaction for load simulation calculations to simulate the actual stress patterns of offshore wind turbine blades under real-world operating conditions. Furthermore, it dynamically maps the concentrated forces and moments obtained from the integrated simulation to a series of nodes on the deformed three-dimensional finite element blade model at each time step, achieving dynamic coupling between the time-varying large deformation of the blade and the applied load, overcoming the unreasonable practice of directly applying static ultimate loads to undeformed blades.

Description

Technical Field

[0001] This invention relates to the fields of renewable energy and wind power generation technology, and in particular to a refined analysis method for the fully coupled dynamic response of wind turbine blades, including the design of floating offshore wind turbine blades. Background Technology

[0002] The loads experienced by wind turbine blades in their service environment can be categorized into two types: aerodynamic loads caused by airflow and its interaction with the blades, and inertial loads generated by gravity, centrifugal force, Coriolis force, vibration, servo control (pitch, yaw, braking), and the movement of the supporting structure. Among these, aerodynamic loads are the most critical loads borne by the wind turbine blades. Based on different aerodynamic load calculation methods, wind turbine blade design and analysis methods can be divided into two categories: one is based on computational fluid dynamics (CFD), which has the advantage of high-fidelity flow field simulation, but disadvantages such as high computational cost, numerical problems, and difficulty in achieving integrated design; the other is based on blade element momentum theory (BEM), an engineering-scale method. Although its accuracy is not as high as CFD, it is efficient, accurate, mature, and easy to integrate. In the wind turbine industry, simulation tools such as OpenFAST, Bladed, and HAWC2 are used to calculate the aerodynamic loads on the blades using BEM-based engineering models and couple them with the structural dynamic response of the entire wind turbine system. However, although the blade structural dynamics calculations using these tools are typically based on simplified beam models suitable for preliminary designs, it is necessary to employ more detailed three-dimensional shell or solid finite element models for detailed structural analysis from the macroscopic structure to the composite layer scale. This verifies the final design and improves the understanding of structural performance. To date, scholars both domestically and internationally have conducted extensive research based on this, attempting to gain a deeper understanding of the mechanical response of blades under different operating conditions by evaluating aspects such as structural integrity, buckling, composite material failure, damage, and stress / strain distribution. However, on the one hand, traditional discrete design methods in industry cannot consider the full coupling of loads during blade load simulation; on the other hand, in the process of conducting fully coupled refined analysis of wind turbine blades, the international academic community directly applies the static ultimate load at a certain moment in the time domain to the three-dimensional finite element model, ignoring the blade deformation that occurs before the ultimate load occurs, and this approach is only applicable to onshore wind turbines. Due to insufficient understanding of blade dynamic response and overly simplified load assumptions, existing design and analysis methods can only try to avoid component damage during service by increasing the safety factor. However, frequent accidents involving offshore wind turbine blades demonstrate that this seemingly conservative approach is not safe or reasonable. Faced with the new challenges brought about by the development trends of "larger scale" and "deeper water" in offshore wind power, and the concept of large blades with a diameter of 100 meters and floating wind turbines, it is necessary to establish a reasonable blade design analysis method and evaluation system. Summary of the Invention

[0003] To overcome the shortcomings of existing design methods that do not fully consider loads and neglect the time-varying motion of blades during refined analysis, this invention provides a technical solution for a refined analysis method, equipment, and medium for the fully coupled dynamic response of wind turbine blades.

[0004] A refined analysis method for the fully coupled dynamic response of wind turbine blades includes:

[0005] Step 1: Use a fully coupled dynamic simulator to perform a series of integrated load simulations for various load conditions in order to obtain the dynamic response of the blade structure that can couple the dynamics of the entire wind turbine system.

[0006] Step 2: The fully coupled dynamic simulator outputs the time-varying displacement of the analysis nodes of the beam model blade in the local blade coordinate system, as well as the coupled structural dynamic reaction loads, including external aerodynamic loads and inertial loads.

[0007] Step 3: Perform coordinate transformation and deintegration operations to convert the local blade coordinate system into the global blade coordinate system and convert the reaction load into an equivalent concentrated external load.

[0008] Step 4: At each time step, the concentrated loads acting on the blade analysis nodes in the overall blade coordinate system are mapped to a series of finite element nodes of the three-dimensional finite element model of the blade using a dynamic mapping algorithm.

[0009] Step 5: Use a general finite element program to perform quasi-static or transient analysis on the high-fidelity blade finite element model, taking into account the large deformation effect. On the one hand, obtain the refined finite element analysis results of the blade at each time step. On the other hand, feed back the spatial position change of the three-dimensional blade geometry at each time step to the dynamic mapping algorithm in step 4 to realize the time-domain dynamic iterative solution.

[0010] Furthermore, in step 1, after inputting external environmental condition parameters and internal wind turbine condition parameters, an integrated solution that simultaneously considers aerodynamics, hydrodynamics, soil-structure interaction, structural dynamics, and servo control dynamics is achieved in the fully coupled dynamic simulator.

[0011] Further, step 2 includes: setting the output coordinate system of the requested fully coupled dynamic simulator in the time domain to a local blade coordinate system that takes into account the local structural pre-torsion and local deflection of the blade, and setting the output parameters to: the local deformation of the blade that evolves with time and space and the blade structural reaction load coupled with aerodynamic loads and inertial loads from structural dynamics.

[0012] Further, step 3 includes: first converting the discrete reaction forces and reaction moments at different blade spanwise sections in the local blade coordinate system from the local blade coordinate system to the global blade coordinate system specified in international standards, and then converting the local blade coordinate system (x... L y L , z L The transformation from the global blade coordinate system (XB, YB, ZB) to the global blade coordinate system (XB, YB, ZB) can be represented by the following equation:

[0013]

[0014] Where θ1 and θ2 represent the local roll and sway deflections of a given blade section, respectively, in radians; γ represents the structural pre-torsion angle in degrees.

[0015] Subsequently, the reaction load R at each blade analysis node in the global blade coordinate system obtained after the coordinate transformation operation is deintegrated and decomposed along the direction from the blade tip to the blade root to obtain the concentrated equivalent external load L acting on a given blade analysis node i. It is assumed that the blade analysis node closest to the blade tip is i. max ,but:

[0016]

[0017] Furthermore, step 3 also includes: if the global blade coordinate system where the equivalent concentrated load is located is inconsistent with the global coordinate system of the established three-dimensional blade finite element model, then it is further converted into the global coordinate system of the established three-dimensional high-fidelity blade finite element model to make it easier to load.

[0018] Further, step 4 includes: using the developed dynamic mapping algorithm to dynamically map the concentrated forces and moments on each given beam element blade analysis node to a series of three-dimensional finite element model nodes in the corresponding blade segment between that node and the next node pointing to the blade tip at each time step, thereby maintaining the mechanical balance of the concentrated equivalent loads on each section.

[0019] Further, step 4 specifically includes: for a given blade analysis node i in the beam element model at a certain time step, let its distance from the blade root along the blade pitch axis be r, then the coordinates of this node are (X... i ,Y i ,r), and the forces acting on it in the flapping direction, the oscillation direction, and the pitching torque at that time step are respectively F X ,i,F Y,i and M Z,i The three-dimensional finite element model segment from i to the next blade analysis node pointing to the tip has N nodes. For coordinates (X... j ,Y jZ j For a given node j in a finite element model, assume the nodal force f in the oscillation direction. X,j and the nodal force f in the swing direction Y,j It follows a linear distribution related to its coordinates, while the axial nodal force f Z,j If the distribution is uniform, the following mechanical equilibrium conditions can be established:

[0020]

[0021] Where, X0 = X j -X i Y0 = Y j -Y i k1 to k7 are unknown coefficients to be determined, which can be calculated using linear algebra.

[0022] Furthermore, step 5 includes: using a general finite element program to perform quasi-static or transient analysis considering large deformation effects, i.e. geometric nonlinearity. On the one hand, it can carry out various refined finite element analyses of the blade as a whole and local components, including stress and strain, fatigue, failure, buckling, and fracture, and extract the time-domain response and evaluation index of the blade structure and material of interest. On the other hand, the finite element program automatically calls the interface program at each time step, thereby transmitting and feeding back the spatial position change of the three-dimensional blade geometry relative to the undeflected position to the dynamic mapping algorithm to achieve time-domain dynamic iterative solution.

[0023] Compared with the prior art, the present invention has the following beneficial technical effects:

[0024] Existing engineering design and analysis methods cannot perform time-domain refined dynamic analysis of high-fidelity offshore wind turbine blade finite element models under dynamic loads coupled with aerodynamics, structural dynamics, hydrodynamics, electromechanical servo control dynamics, and soil-structure interaction effects. Simplified load simulation methods and a lack of understanding of the true dynamic response of the blades have led designers to blindly increase safety factors to minimize blade damage during service, but frequent engineering accidents demonstrate that this approach is neither safe nor reasonable. This invention proposes an algorithm for refined dynamic response analysis of three-dimensional high-fidelity blade finite element models within an integrated framework. This algorithm enables refined analysis of the fully coupled dynamic response of offshore wind turbine blades, providing feasible and reliable technical support for examining and evaluating time-varying stress / strain distribution, dynamic buckling behavior, and fatigue, failure, and fracture behavior of composite materials under actual operating conditions. On the one hand, it solves the technical challenges of not being able to consider complex turbulent wind conditions, the actual servo control strategies of the whole system (blade pitch, nacelle yaw, shutdown), and the coupling effect between the motion of the substructure (such as pile-soil interaction and six-degree-of-freedom motion of the floating body) and the load on the upper blade structure during load simulation. On the other hand, it realizes the dynamic coupling between large blade deformation and the applied load, overcoming the unreasonable practice of applying static ultimate loads to undeformed blades. Attached Figure Description

[0025] Figure 1 This is a flowchart of the modeling process for Example 1;

[0026] Figure 2 This is a two-dimensional projection schematic diagram of the three-dimensional geometric model of a 5MW offshore wind turbine blade in Example 1;

[0027] Figure 3 This is a detailed modeling diagram of the composite material laminate structure used for the blade in Example 1;

[0028] Figure 4 This is a schematic diagram of a high-fidelity three-dimensional finite element model based on layered shell elements in Example 1;

[0029] Figure 5 This is a schematic diagram of the integrated model of fixed and floating offshore wind turbines in Example 1. The left side of the diagram shows the integrated model of the fixed offshore wind turbine, and the right side shows the integrated model of the floating offshore wind turbine.

[0030] Figure 6 This is a schematic diagram of the refined analysis framework for the fully coupled dynamic response of offshore wind turbine blades in Example 2;

[0031] Figure 7 This is a schematic diagram of the blade coordinate system specified in the international standard DNVGL-ST-0376 in Example 2;

[0032] Figure 8 This is a schematic diagram of the coordinate system of the three-dimensional high-fidelity blade finite element model in Example 2;

[0033] Figure 9 This is a schematic diagram of the time-domain refined analysis results (von Mises stress distribution) in Example 2. Detailed Implementation

[0034] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0035] It should be noted that, unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of this application.

[0036] Example 1

[0037] Please see Figure 1 Before conducting a refined analysis of the fully coupled dynamic response of wind turbine blades, modeling is required. The modeling process is as follows:

[0038] a. Establish a three-dimensional high-fidelity finite element model of the blade.

[0039] like Figure 2 and Figure 3 As shown, this document defines the complex geometry of wind turbine blades, including two-dimensional airfoils, chord length, twist angle, three-dimensional geometry, and shear web location; physical and mechanical parameters of constituent materials such as type, density, strength, elastic modulus, and composite material failure criteria; and the layup sequence, orientation, and thickness of laminated composite material structures in various components such as the leading edge, leading edge panel, trailing edge, trailing edge panel, main spars, and shear web. Figure 4 As shown, a high-fidelity three-dimensional finite element model based on layered shell elements or solid elements is established and imported into general finite element analysis software such as ANSYS or Abaqus for subsequent refined analysis.

[0040] b. Establish an integrated whole-machine model that balances fidelity and computational cost.

[0041] like Figure 5As shown, an integrated model of an offshore wind turbine is established in wind turbine simulation design software, including the rotor nacelle assembly (RNA), corresponding servo control strategies (blade pitch, nacelle yaw, braking, and shutdown), tower, and substructure (support structure for stationary wind turbines, and floating platform and mooring system for floating wind turbines). The blade model can be simplified based on different structural dynamics calculation methods, including a bending-dominant calculation method based on Euler-Bernoulli beam theory and the assumed modal superposition method, and a blade structural dynamics calculation method based on geometrically accurate beam theory (GEBT) and Legendre spectral finite element method (LSFE) that can consider fully geometrical nonlinearity.

[0042] c. Establish an external environment model

[0043] According to international standards such as IEC and DNV, reasonable wind field parameters (wind speed, wind direction, wind spectrum, turbulence intensity, etc.), wave field parameters (sense wave height, peak frequency, wave direction, wave spectrum, etc.), and ocean current model parameters (current velocity, velocity distribution, etc.) are selected to simulate external environmental conditions such as wind, waves, and currents, so as to calculate external environmental loads in integrated simulation. In addition, soil parameters are determined, and reasonable pile-soil and anchor-soil models are used to describe the soil-structure interaction of specific sites. For example, for the monopile foundation of a stationary wind turbine, it can be regarded as a horizontally loaded pile, and a distributed nonlinear spring is used to describe the relationship between the soil reaction force p per unit pile length above the rotation point and the horizontal displacement y of the pile, considering the influence of the soil failure mechanism around the pile on the py curve; and a centralized nonlinear rotating spring is set to describe the relationship between the soil reaction moment M at the rotation point and the rotation angle θ of the rotation point. For the anchor-soil interaction of a floating wind turbine, a set of translational, rotational, and translational-rotational coupled springs can be set at each anchor-soil interface to describe the foundation flexibility in the form of a linearized 6×6 stiffness matrix.

[0044] Example 2

[0045] Please see Figure 6 A refined analysis method for the fully coupled dynamic response of wind turbine blades is proposed. The core calculation modules of this method include: a fully coupled dynamic simulator, a coordinate transformation algorithm, a dynamic mapping algorithm, and finite element analysis code, comprising the following steps:

[0046] Step 1: Use a fully coupled dynamic simulator to perform a series of integrated load simulations for various load conditions to obtain the dynamic response of the blade structure that can couple the dynamics of the entire wind turbine system. Specifically, this includes:

[0047] First, external environmental parameters such as wind, waves, ocean currents, and soil parameters, as well as internal parameters such as wind turbine configuration and operating mode, are input into a fully coupled dynamic simulator, such as the open-source wind turbine design software OpenFAST or the commercial wind turbine design software Bladed and HAWC2. This embodiment specifically uses OpenFAST as the fully coupled dynamic simulator. The blade structure dynamics calculation uses the ElastoDyn module, which performs an integrated solution that simultaneously considers aerodynamics, hydrodynamics, structural dynamics (including soil-structure interaction), and electrical system (servo) dynamics. This takes into account the coupling of external loads and the interaction between external loads, the control system, and the internal structural response. Figure 6 As shown.

[0048] Step 2: The fully coupled dynamic simulator outputs the time-varying displacements of the analysis nodes of the beam model blade in the local blade coordinate system, as well as the coupled structural dynamic reaction loads, including external aerodynamic loads and inertial loads. Specifically, this includes:

[0049] The output coordinate system of the requested fully coupled dynamic simulator in the time domain is set to a local blade coordinate system that takes into account the local structural pre-torsion and local deflection of the blade. The output parameters are set to: the local deformation of the blade that evolves over time and space, and the blade structural reaction loads coupled with aerodynamic loads and inertial loads from structural dynamics. Once the fully coupled dynamic simulator runs successfully, these outputs will be automatically transferred to a program interface, such as MATLAB or Python, to perform a series of coordinate transformations and load decomposition operations, as well as subsequent dynamic mapping algorithms.

[0050] Step 3 involves performing coordinate transformation and de-integration operations to convert the local blade coordinate system to the global blade coordinate system and to convert the reaction load into an equivalent concentrated external load. Specifically, this includes:

[0051] To facilitate the subsequent application of loads to the three-dimensional high-fidelity finite element model of the blade, the discrete reaction forces and reaction moments at different blade spanwise sections in the local blade coordinate system are first converted from the local blade coordinate system to... Figure 7 The blade coordinate system shown is specified in DNVGL-ST-0376 (constant along the blade span and independent of blade deflection and structural pre-torsion). From the local blade coordinate system (x... L y L , z L The transformation from the global blade coordinate system (XB, YB, ZB) to the global blade coordinate system (XB, YB, ZB) can be represented by the following equation:

[0052]

[0053] Where θ1 and θ2 represent the local roll and sway deflections of a given blade section, respectively, in radians; γ represents the structural pre-torsion angle in degrees.

[0054] Subsequently, the reaction load R at each blade analysis node in the global blade coordinate system obtained after the coordinate transformation operation is deintegrated and decomposed along the direction from the blade tip to the blade root to obtain the concentrated equivalent external load L acting on a given blade analysis node i. It is assumed that the blade analysis node closest to the blade tip is i. max ,but:

[0055]

[0056] It is worth noting that if the global blade coordinate system in which the equivalent concentrated load is located is inconsistent with the global coordinate system of the established three-dimensional blade finite element model, it should be further converted to the global coordinate system of the established three-dimensional high-fidelity blade finite element model to facilitate loading. For example, Figure 8 The global Cartesian coordinate system of the three-dimensional high-fidelity blade finite element model established in this invention is shown. Its X-axis points from the trailing edge to the leading edge and is parallel to the chord of the zero-twist blade station. The Z-axis points along the pitch axis from the blade root to the blade tip. The Y-axis is orthogonal to the X and Z axes, thus forming a right-handed coordinate system. Therefore, the transformation from the global blade coordinate system to the global Cartesian coordinate system of the three-dimensional finite element model is as follows:

[0057]

[0058] Step 4: Using a dynamic mapping algorithm, at each time step, the concentrated loads acting on the blade analysis nodes in the overall Cartesian coordinate system are mapped to a series of finite element nodes of the blade's three-dimensional finite element model using a reasonable method. Specifically, this includes:

[0059] like Figure 6 As shown, the dynamic mapping algorithm proposed in this embodiment dynamically maps the concentrated forces and moments on each given beam element blade analysis node to a series of three-dimensional finite element model nodes within the corresponding blade segment between that node and the next node pointing towards the blade tip at each time step, thereby maintaining the mechanical equilibrium of the concentrated equivalent loads on each cross section. Specifically, for a given blade analysis node i of the beam element model at a certain time step, let its distance from the blade pitch axis to the blade root be r, then the coordinates of this node are (X... i ,Y i ,r), and the forces acting on it in the flapping direction, the oscillation direction, and the pitching torque at that time step are respectively F X,i ,F Y,i and M Z,iThe three-dimensional finite element model segment from node i to the next blade analysis node pointing to the tip has N nodes. For coordinates (X... j ,Y j Z j For a given node j in a finite element model, assume the nodal force f in the oscillation direction. X,j and the nodal force f in the swing direction Y,j It follows a linear distribution related to its coordinates, while the axial nodal force f Z,j The distribution is uniform (constantly changing with j from 1 to N). Therefore, the following mechanical equilibrium conditions can be established:

[0060]

[0061] Where, X0 = X j -X i Y0 = Y j -Y i k1 to k7 are unknown coefficients to be determined, which can be calculated using linear algebra. It is worth noting that, given the shape of the airfoil, it is assumed that only the force in the flapping direction (f) exists. Y,j ) for M Z,i F made a contribution X,i It is balanced and does not generate torque. In addition, the coordinates of each blade analysis node i and each three-dimensional finite element model node j are time-varying and need to be updated accordingly at each time step.

[0062] Step 5 involves using a general-purpose finite element program to perform a quasi-static or transient analysis considering large deformation effects, i.e., geometric nonlinearity. This yields refined finite element analysis results for the blade at that time step and feeds back the changes in the three-dimensional blade geometry to the dynamic mapping algorithm for dynamic iterative solution. Specifically, this includes:

[0063] In this embodiment, the general-purpose finite element software ANSYS is used to perform refined time-domain finite element analysis. It performs quasi-static analysis considering large deformation effects on the established high-fidelity three-dimensional layered shell model of the blade, and serves as a post-processor that can process simulation results according to a series of ANSYS Mechanical APDL (ANSYS Parametric Design Language) commands. On one hand, it can perform various types of refined finite element analyses, such as time-domain stress / strain distribution, buckling, and fatigue, of the blade as a whole and its local components, and extract the time-domain loads of the blade structure and materials of interest, such as... Figure 9This demonstrates the von Mises stress distribution (unit: Pa) of a blade at a specific time step in the time domain. On the other hand, ANSYS automatically calls the MATLAB interface program at each time step, thereby transmitting and feeding back the changes in the 3D blade geometry (changes in the nodal coordinates of the finite element model) relative to the undeflected position to the dynamic mapping algorithm for dynamic iterative solution. Besides ANSYS, other commercial finite element analysis codes, such as Abaqus, can also be used to perform the same task.

[0064] It should be noted that this invention is not limited to offshore wind power, but is equally applicable to onshore wind power; and this invention is not limited to wind turbine blades, but is also applicable to other components of the wind turbine (such as blades, hubs, transmission systems and towers) using the same or similar methods.

[0065] The embodiments described above are merely specific and detailed examples of the embodiments described in this application, and should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the scope of protection of this application. Therefore, the scope of protection of this patent application should be determined by the appended claims.

Claims

1. A refined analysis method for the fully coupled dynamic response of wind turbine blades, characterized in that, include: Step 1: Use a fully coupled dynamic simulator to perform integrated load simulation on various load conditions in order to obtain the dynamic response of the blade structure that can couple the dynamics of the entire wind turbine system. Step 2: The fully coupled dynamic simulator outputs the time-varying displacement of the analysis nodes of the beam model blade in the local blade coordinate system, as well as the coupled structural dynamic reaction loads, including external aerodynamic loads and inertial loads. Step 3: Perform coordinate transformation and deintegration operations to convert the local blade coordinate system into the global blade coordinate system and convert the reaction load into an equivalent concentrated external load. Step 4: Using a dynamic mapping algorithm, at each time step, the concentrated loads acting on the blade analysis nodes in the global blade coordinate system are mapped to the finite element nodes of the three-dimensional finite element model of the blade using a reasonable method. Specifically, for a given blade analysis node i in the beam element model at a certain time step, let its distance from the blade root along the blade pitch axis be r, then the coordinates of this node are (X... i ,Y i ,r), and the forces acting on it in the flapping direction, the oscillation direction, and the pitching torque at that time step are respectively F X,i ,F Y,i and M Z,i The three-dimensional finite element model segment from i to the next blade analysis node pointing to the tip has N nodes. For coordinates (X... j ,Y j Z j For a given node j in a finite element model, assume the nodal force f in the oscillation direction. X,j and the nodal force f in the swing direction Y,j It follows a linear distribution related to its coordinates, while the axial nodal force f Z,j If the distribution is uniform, then the following mechanical equilibrium conditions are established: ， Where, X0=X j -X i Y0=Y j -Y i k1 to k7 are unknown coefficients to be determined, which are calculated using linear algebra. Step 5: Use a general finite element program to perform quasi-static or transient analysis on the high-fidelity blade finite element model, taking into account the large deformation effect. On the one hand, obtain the refined finite element analysis results of the blade at each time step. On the other hand, feed back the spatial position change of the three-dimensional blade geometry at each time step to the dynamic mapping algorithm in step 4 to realize the time-domain dynamic iterative solution.

2. The refined analysis method for the fully coupled dynamic response of wind turbine blades according to claim 1, characterized in that, In step 1, after inputting external environmental condition parameters and internal wind turbine condition parameters, an integrated solution that simultaneously considers aerodynamics, hydrodynamics, soil-structure interaction, structural dynamics, and servo control dynamics is achieved in the fully coupled dynamic simulator.

3. The method according to claim 1, wherein, Step 2 includes: setting the output coordinate system of the requested fully coupled dynamic simulator in the time domain to a local blade coordinate system that takes into account the local structural pre-torsion and local deflection of the blade, and setting the output parameters to: the local deformation of the blade that evolves with time and space and the blade structural reaction load coupled with aerodynamic loads and inertial loads from structural dynamics.

4. The full-coupled dynamic response refinement analysis method of a wind turbine blade according to claim 1, wherein, Step 3 includes: first, converting the discrete reaction forces and reaction moments at different blade spanwise sections in the local blade coordinate system to the global blade coordinate system specified in international standards, and then converting them from the local blade coordinate system (x... L y L , z L The transformation from the global blade coordinate system (XB, YB, ZB) to the global blade coordinate system is represented by the following equation: ， Where θ1 and θ2 represent the local roll and sway deflections of a given blade section, respectively, in radians; γ represents the structural pre-torsion angle in degrees. Subsequently, the reaction load R at each blade analysis node in the global blade coordinate system obtained after the coordinate transformation operation is deintegrated and decomposed along the direction from the blade tip to the blade root to obtain the concentrated equivalent external load L acting on a given blade analysis node i. It is assumed that the blade analysis node closest to the blade tip is i. max ,but: 。 5. The method of claim 4, wherein the method is characterized by, Step 3 further includes: if the global blade coordinate system where the equivalent concentrated load is located is inconsistent with the global coordinate system of the established three-dimensional blade finite element model, then it is further converted into the global coordinate system of the established three-dimensional high-fidelity blade finite element model to make it easier to load.

6. The method of claim 1, wherein, Step 5 includes: using a general finite element program to perform quasi-static or transient analysis considering large deformation effects, i.e. geometric nonlinearity. On the one hand, it can carry out various refined finite element analyses of the blade as a whole and local components, including stress and strain, fatigue, failure, buckling, and fracture, and extract the time-domain response and evaluation index of the blade structure and material of interest. On the other hand, the finite element program automatically calls the interface program at each time step, thereby transmitting and feeding back the spatial position change of the three-dimensional blade geometry relative to the undeflected position to the dynamic mapping algorithm to achieve time-domain dynamic iterative solution.

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