A hybrid tower wind turbine dynamic response calculation method and system

Abstract

The present invention discloses a method and system for calculating the dynamic response of a hybrid tower wind turbine, the method comprising the following steps: decoupling the hybrid tower wind turbine into an impeller system and a tower system, the impeller system comprising blades and a nacelle, and the tower system comprising a supporting tower; considering the interaction between the impeller system and the tower system, performing coupling calculation to obtain the dynamic response of the impeller system and the tower system, performing data exchange between the impeller system and the tower system at each solution time step of the coupling calculation, performing multi-flexible body system calculation on the impeller system during the coupling calculation, and performing finite element method calculation on the tower system. The present invention solves the shortcoming that the multi-body dynamics calculation method is difficult to calculate complex tower structures, adopts a subsystem approach to adapt to more complex tower models, and adopts different calculation methods for subsystems of different complexities, thereby improving the efficiency of wind turbine dynamic response simulation.

Description

Technical Field

[0001] The invention relates to a wind turbine power simulation technology, and in particular to a hybrid tower wind turbine power response calculation method and system. Background Art

[0002] As a complex structure, wind turbines are composed of blades, nacelle transmission system and lower support structure (including tower body and foundation). With the continuous development of wind power generation technology, hybrid tower design has received more and more attention because it can improve wind power generation efficiency while reducing overall construction and operation costs. In addition, hybrid towers can also simplify transportation and installation processes through modular design, which is particularly important for remote or complex terrain areas.

[0003] For the dynamic calculation of traditional all-steel tower wind turbines, multi-body dynamics is often used for modeling and solving. Multi-body dynamics is a mechanical discipline that is closely integrated with large and complex engineering objects. Its research object is a system of multiple objects connected to each other. The wind turbine is simplified into multiple degrees of freedom representing blades, nacelles, foundations, etc., and the dynamic equations of each degree of freedom of the wind turbine are derived using the Euler-Lagrange equations. This modeling and calculation method takes into account the coupling of the impeller motion (including its rotation and motion under external loads) and the motion of the lower support structure, and obtains the integrated motion response of the wind turbine under external loads.

[0004] However, for hybrid tower wind turbines, especially steel-reinforced concrete hybrid tower wind turbines, this type of method is difficult to consider the nonlinear characteristics of the concrete part. The results of its solution can only be reflected in the degree of freedom, and it is difficult to reflect the mechanical response of the real structure. The finite element method is often used for complex and delicate structures to obtain more mechanical characteristics and more accurate results. Therefore, some studies have used the finite element method to establish a structural model for more detailed analysis. However, this method is difficult to consider the interaction between the impeller and the tower. It can only simplify the impeller into a damping unit and use empirical values ​​or experimental values ​​to determine the mechanical characteristics of the damping unit, which is difficult to reflect the real dynamic response of the wind turbine. At the same time, it will also bring high computational costs in the time history analysis of dynamic response. Summary of the invention

[0005] The technical problem to be solved by the present invention is as follows: In view of the above-mentioned problems in the prior art, a method and system for calculating the dynamic response of a hybrid tower wind turbine are provided, and a dynamic model that can accurately express the hybrid tower wind turbine while ensuring calculation efficiency is established, thereby solving the shortcoming that the multi-body dynamics calculation method is difficult to calculate complex tower structures.

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

[0007] A method for calculating the dynamic response of a hybrid tower wind turbine comprises the following steps:

[0008] The decoupled hybrid tower wind turbine comprises an impeller system and a tower system, wherein the impeller system comprises blades and a nacelle, and the tower system comprises a supporting tower body;

[0009] Considering the interaction between the impeller system and the tower system, coupling calculation is performed to obtain the dynamic response of the impeller system and the tower system. Data exchange between the impeller system and the tower system is performed at each solution time step of the coupling calculation. During the coupling calculation, multi-flexible body system calculation is performed on the impeller system, and finite element method calculation is performed on the tower system.

[0010] Furthermore, a dynamics solver is used when performing multi-flexible body system calculations on the impeller system, and the dynamics solver uses the Euler-Lagrange equations to derive the dynamics equations; an OpenSEES solver is used when performing finite element method calculations on the tower system, and the OpenSEES solver uses OpenSEES software for modeling and simulation.

[0011] Furthermore, when the coupling calculation is performed considering the interaction between the impeller system and the tower system, a non-iterative coupling calculation is performed, including:

[0012] Obtaining the dynamic response of the impeller system and / or the tower system at the previous time step, inputting the dynamic response of the impeller system and / or the tower system at the previous time step into the external force calculation formula, and obtaining the external force exerted on the tower system and / or the impeller system at the current time step;

[0013] The dynamic response of the tower system at the current time step is calculated using the OpenSEES solver according to the external forces acting on the tower system at the current time step, and / or the dynamic response of the impeller system at the current time step is calculated using the dynamics solver according to the external forces acting on the impeller system at the current time step.

[0014] Furthermore, when the coupling calculation is performed considering the interaction between the impeller system and the tower system, an iterative coupling calculation is performed, including:

[0015] Obtain the dynamic response of the impeller system and / or tower system in the previous iteration step in the current time step, input the external load of the current time step and the dynamic response of the impeller system or tower system in the previous iteration step into the external force calculation formula, and obtain the external force exerted on the tower system or impeller system in the current iteration step;

[0016] Compare the external force on the tower system or impeller system in the current iteration step with the external force on the tower system or impeller system in the previous iteration step, and determine whether the convergence condition is met;

[0017] If the convergence condition is not met, the OpenSEES solver is used to calculate the dynamic response of the tower system in the current iteration step according to the external force applied to the tower system in the current iteration step, or the dynamics solver is used to calculate the dynamic response of the impeller system in the current iteration step according to the external force applied to the impeller system in the current iteration step, and then the external load of the current time step and the dynamic response of the tower system or impeller system in the current iteration step are input into the external force calculation formula to obtain the external force applied to the impeller system or tower system in the current iteration step, and finally the dynamics solver is used to calculate the dynamic response of the impeller system in the current iteration step according to the external force applied to the impeller system in the current iteration step, or the OpenSEES solver is used to calculate the dynamic response of the tower system in the current iteration step according to the external force applied to the tower system in the current iteration step;

[0018] If the convergence condition is met, enter the next time step and calculate the iterative initial value of the next time step.

[0019] Furthermore, the convergence condition is specifically: the difference between the external force applied to the tower body system or the impeller system in the current iteration step and the external force applied to the tower body system or the impeller system in the previous iteration step is less than a specified error limit.

[0020] Furthermore, the calculation of the initial value of the iteration for the next time step includes:

[0021] The OpenSEES solver is used to solve the stiffness value of the tower system and update it to the preset wind turbine dynamics model. The updated wind turbine dynamics model is solved to obtain the iterative initial value of the dynamic response of the impeller system and the tower system in the next time step.

[0022] Furthermore, before obtaining the dynamic response of the impeller system and / or tower system in the previous iteration step in the current time step, a step of calculating the external load of the previous time step is also included, including:

[0023] Under the action of the actual wind field, the blade element momentum theory is used to calculate the wind load on the blades of the impeller system, and the generalized external force of each degree of freedom of the impeller system and the tower system is calculated using the principle of virtual work.

[0024] Furthermore, when using the dynamics solver and the OpenSEES solver, the calculation formula is as follows:

[0025]

[0026] in, is the dynamics solver, For the OpenSEES solver, M blade is the mass matrix of the blades of the impeller system, Q blade ,Q tower are the external load forces of the impeller system and the tower system respectively, is the generalized force generated by the tower system movement on the impeller system, is the generalized force generated by the impeller system on the tower system, x tower , are the displacement, velocity and acceleration variables in the dynamic response of the tower system, x blade , are the displacement, velocity and acceleration variables in the dynamic response of the impeller system, C blade ,K blade They are the damping and stiffness matrices of the six degrees of freedom of the blades of the impeller system.

[0027] Furthermore, the external force calculation formula is expressed as follows:

[0028]

[0029] in, and f blade is the generalized force generated by the tower system movement on the impeller system, and f tower is the generalized force generated by the impeller system on the tower system, the generalized force f blade With f tower writing:

[0030]

[0031] Among them, M blade ,C blade ,K blade are the mass, damping and stiffness matrices of the six degrees of freedom of the blades of the impeller system, M tower ,C tower ,K tower are the mass, damping and stiffness matrices of the two degrees of freedom at the top of the tower system.

[0032] The present invention also provides a hybrid tower wind turbine dynamic response calculation system, comprising a microprocessor and a computer storage medium connected to each other, wherein the microprocessor is programmed or configured to execute any one of the hybrid tower wind turbine dynamic response calculation methods.

[0033] Compared with the prior art, the advantages of the present invention are:

[0034] The present invention adopts a subsystem approach to decouple the hybrid tower wind turbine into an impeller system and a tower system, which is conducive to considering a more complex tower model. At the same time, the interaction between the two subsystems is considered for coupling calculation, wherein the impeller system is calculated using a multi-flexible system, and the tower system is calculated using a finite element method. Different calculation methods are used for systems of different complexity, thereby improving the efficiency of the dynamic response simulation of the wind turbine. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 Schematic diagram of the joint simulation model of the hybrid tower wind turbine in an embodiment of the present invention.

[0036] Figure 2 Schematic diagram of force-force coupling of a hybrid tower wind turbine in an embodiment of the present invention.

[0037] Figure 3 Schematic diagram of the joint simulation system of the hybrid tower wind turbine in an embodiment of the present invention.

[0038] Figure 4 Schematic diagram of the joint simulation model architecture of the hybrid tower wind turbine in an embodiment of the present invention.

[0039] Figure 5 This is a flow chart of iterative solution during coupling calculation in an embodiment of the present invention.

[0040] Figure 6 Schematic diagram of the software framework of an embodiment of the present invention. DETAILED DESCRIPTION

[0041] The present invention is further described below in conjunction with the accompanying drawings and specific preferred embodiments, but the protection scope of the present invention is not limited thereby.

[0042] Embodiment 1

[0043] Before introducing the specific embodiments of the present invention, the theoretical derivation process is first described.

[0044] like Figure 1 As shown in Figure 2, the hybrid tower wind turbine can be considered as a multi-flexible system. With subsystem S t Coupling, the two are connected by a fixed connection. Multi-flexible system Multiple soft bodies S bi It can be solved as a complete multi-flexible body system composed of rigid bodies, which will be explained in detail below. With subsystem S t , which can be regarded as a black box, will produce different output results under different input conditions, which can be expressed as:

[0045]

[0046] where x m ,x s Respectively represent the responses of the multi-flexible system and subsystem. The responses can be structural response variables such as displacement, velocity and acceleration, while is the generalized force acting on the two systems.

[0047] like Figure 2 As shown in Figure 1, and according to equation (1), the two systems can be separated by force-force coupling. Each system is solved using an independent solver, and the system response variables are obtained at each macro time step, and the generalized loads of the other system are calculated for input calculation. The macro time step here refers to the time step corresponding to the data exchange between the systems.

[0048] like Figure 3 As shown, for multi-body systems, their dynamic equations can be derived using methods such as the Euler-Lagrange equations, and solved using algorithms such as Newmark or Runge-Kutta. For subsystems, their structural responses can be solved using the implicit function g(). The two systems pass the structural displacements, velocities, and accelerations to the joint simulation manager to calculate the generalized forces acting on the other system. When the computer performance is powerful enough or the interaction cost between the two systems is small, a smaller macro time step can be used to reduce errors. However, in mature and stable time integration algorithms, adaptive time steps are usually used to improve solution stability and shorten solution time. For simplicity, this article will use linear interpolation to calculate the response outputs of each subsystem in other systems within their respective sub-time steps, and for Figure 2 The model performs input generalized force interpolation calculations.

[0049] For a wind turbine, the wind turbine as a whole can be regarded as a multi-body system. It includes three blade soft bodies S b1 ,S b2 ,S b3 and the nacelle rigid body, hereinafter referred to as the impeller system, while the subsystem S is the tower model established by the finite element method, hereinafter referred to as the tower system. The dynamic response of the impeller system will affect the dynamic response of the tower system. The Euler-Lagrange equation is used to establish an eight-degree-of-freedom multi-body dynamic model including the blade soft body of the impeller system and the tower soft body of the tower system, and the Runge-Kutta equation is used to solve its dynamic equations. The motion equations of the eight-degree-of-freedom hybrid tower wind turbine dynamic model are as follows:

[0050]

[0051] in, They are the mass matrix, stiffness matrix and damping matrix of the system. Due to the potential energy term caused by the rotation of the impeller, the system matrix changes with time. The mass matrix of the hybrid tower wind turbine system can be written as:

[0052]

[0053] In the formula

[0054]

[0055] Among them, M nac ,M hub They represent the masses of the wind turbine nacelle and hub of the impeller system respectively. It represents the mass per unit length of the tower system.

[0056] The stiffness matrix of the hybrid tower wind turbine system is:

[0057]

[0058] Where:

[0059]

[0060] The damping matrix of the hybrid tower wind turbine system is:

[0061]

[0062] Where:

[0063]

[0064] where c b,e ,c b,f represent the damping of the blade swing direction and flapping direction of the impeller system, respectively, and c 7 ,c 8 They represent the damping of the tower system in the front-rear direction and the side direction respectively.

[0065] Formula (2) actually includes the six degrees of freedom of the wind turbine blades and the two degrees of freedom of the lower support structure, so it can be expanded:

[0066]

[0067] Among them, M blade ,C blade ,K blade are the mass, damping and stiffness matrices of the six degrees of freedom of the blades of the impeller system, M tower ,C tower ,K tower is the mass, damping and stiffness matrix of the two degrees of freedom at the top of the tower system, Q blade ,Q tower They are respectively the generalized force of environmental load on the blades of the impeller system and the generalized force of environmental load on the tower body of the tower system. Due to the interaction between the upper and lower structures, in fact, each matrix is ​​not a diagonal matrix, but has non-zero terms in both the upper and lower triangles of the matrix, and due to the rotation of the impeller, each matrix also presents the characteristics of an asymmetric matrix.

[0068] Remember F blade ,F toweris the external force on each part of the wind turbine impeller system after decoupling from the tower system. For the impeller system and the tower system, the dynamic equation can be written in the following form:

[0069]

[0070] By observing the above formula, it can be found that the impeller system of the upper structure and the tower system of the lower structure can actually be written in the form of standard dynamic equations. For the impeller system of the upper structure, although it contains a flexible body, the deformation characteristics of the flexible body can still be represented by the modal synthesis method. Therefore, the Runge-Kutta method can be used to solve its dynamic equations to ensure its solution efficiency. As for the tower system of the lower structure, due to the complexity of its structural characteristics, the finite element method will be used to establish a more sophisticated and complex nonlinear tower model in OpenSEES and solve it. The modeling method of OpenSEES is a general finite element modeling method, which is calculated using beam units according to actual geometric parameters and corresponding material parameters. The specific implementation process can be known to those skilled in the art by consulting relevant materials, and this embodiment will not be repeated. Therefore, formula (10) can be rewritten as:

[0071]

[0072] where x, x, and x are the displacement, velocity, and acceleration variables of the corresponding system, respectively. Specifically, x tower , are the displacement, velocity and acceleration variables in the dynamic response of the tower system, x blade , are the displacement, velocity and acceleration variables in the dynamic response of the impeller system, represents the dynamics solver, represents the OpenSEES solver. For generalized forces In fact, it is the generalized force f generated by the tower system movement on the impeller system of the superstructure blade , and the generalized force In fact, it is the generalized force f generated by the impeller system movement of the superstructure on the tower system. tower .

[0073] From formula (9), we can know that the external load forces for the impeller system of the upper structure and the tower system of the lower structure are Q blade ,Q tower , and the generalized force f between the impeller system of the upper structure and the tower system of the lower structure tower The generalized force f generated by the tower system movement of the lower structure on the impeller system of the upper structure blade You can write:

[0074]

[0075] Substitute equation (11) into equation (12) to obtain the generalized force λ between systems: c for:

[0076]

[0077] Based on the above derivation, this embodiment proposes a method for calculating the dynamic response of a hybrid tower wind turbine, such as Figure 4 As shown, the following steps are included:

[0078] The decoupled hybrid tower wind turbine comprises an impeller system and a tower system, wherein the impeller system comprises blades and a nacelle, and the tower system comprises a supporting structure, specifically a supporting tower body of a steel-reinforced concrete structure;

[0079] Considering the interaction between the impeller system and the tower system, coupling calculation is performed to obtain the dynamic response of the impeller system and the tower system. Data exchange between the impeller system and the tower system is performed at each solution time step of the coupling calculation, and the force balance between the impeller system and the tower system is completed through iteration to solve the accurate system response. During the coupling calculation, multi-flexible system calculation is performed on the impeller system, and finite element method calculation is performed on the tower system.

[0080] In this embodiment, a dynamics solver is used to perform multi-flexible body system calculations on the impeller system. As described above, the dynamics solver uses the Euler-Lagrange equations to derive the dynamics equations. An OpenSEES solver is used to perform finite element method calculations on the tower system. As described above, the OpenSEES solver uses OpenSEES software for modeling and simulation.

[0081] like Figure 4 As shown, although the impeller system and the tower system are separated in this embodiment, it can be found from formula (12) that the dynamic response of the impeller system is part of the external force calculation of the tower system, and the dynamic response of the tower is actually also part of the external force calculation of the impeller. Therefore, there is still interaction between the two, which is actually a problem faced by multi-system coupling calculation. In this regard, there are usually two types of calculation simulations: iterative coupling and non-iterative coupling.

[0082] Non-iterative coupling means that under a sufficiently small time analysis step, the response of the impeller system and the tower system in the previous time step can be used to calculate the external forces on the impeller system and the tower system in the current time step, so as to solve the wind turbine impeller system and the tower system respectively. Specifically, the steps for non-iterative coupling calculation include:

[0083] Obtain the dynamic response of the impeller system and / or the tower system at the previous time step, input the dynamic response of the impeller system and / or the tower system at the previous time step into the external force calculation formula, i.e., formula (13), to obtain the external force exerted on the tower system and / or the impeller system at the current time step;

[0084] Through formula (11), the dynamic response of the tower system at the current time step is calculated based on the external force applied to the tower system at the current time step using the OpenSEES solver, and / or the dynamic response of the impeller system at the current time step is calculated based on the external force applied to the impeller system at the current time step using the dynamic solver.

[0085] Non-iterative coupling avoids the reduction step of solving the internal system and reduces the control of the solver. However, it is very sensitive to the choice of time step. Too small a time step will lead to an increase in calculation time and interaction time between systems, while too large a time step will cause the joint simulation system solution to not converge.

[0086] Iterative coupling refers to iterating each time step so that the interaction node states between the two systems are balanced. Generally speaking, compared with the iterative coupling method, the non-iterative coupling method has higher requirements for the selection of time steps and poorer stability. Therefore, in this embodiment, the iterative coupling method is used to calculate the response of each time step of the wind turbine for error control.

[0087] From formula (13), we can find that the generalized force λ between systems c It can be written as the generalized force generated by the tower system motion on the impeller system The form of the generalized force generated by the impeller system movement on the tower system , so it can be used as an iterative variable for calculation.

[0088] The iterative coupling calculation process of this implementation is as follows Figure 5 As shown, first, the solver needs to be initialized before the solution calculation begins, and the initial values ​​​​of the displacement, velocity and acceleration of each degree of freedom of the system need to be selected. Figure 5 The solvers that need to be initialized include: MBS-FEM solver, which is a multi-body dynamics-finite element hybrid solver and is the solver for actual calculation; MBS solver, which is a multi-body dynamics solver and is used to determine the initial response value of the MBS-FEM solver in each time step. This is because the MBS-FEM solver actually performs iterative approximation on the response value in each time step.

[0089] Secondly, under the action of the actual wind field, the blade element momentum theory is used to calculate the wind load on the blades of the impeller system, and the principle of virtual work is used to calculate the generalized external force of each degree of freedom of the impeller system and the tower system of the wind turbine system. The relevant specific calculation process can be obtained by technical personnel in this field by referring to the materials, and will not be repeated in this embodiment.

[0090] Finally, the above data are substituted into formula (13) to solve the external forces of the impeller system and the tower system. In formula (13), the generalized forces of the two degrees of freedom at the top of the tower are calculated based on the six degrees of freedom response obtained by the generalized force calculation of the six degrees of freedom of the blade (RK45); the generalized forces of the six degrees of freedom of the blade are calculated based on the two degrees of freedom response obtained by the generalized force calculation of the two degrees of freedom of the tower (OpenSEES). Then the obtained external forces are substituted into formula (11) to solve the dynamic response of the impeller system and the tower system, that is, the displacement and velocity response of each degree of freedom through the corresponding solver. The dynamic response of the impeller system and the tower system is substituted into formula (13) again to solve the new external forces of the impeller system and the tower system, and compared with the external forces in the previous iteration step to complete an iteration.

[0091] Specifically, Figure 5 The process of one iteration of iterative coupling calculation is as follows:

[0092] Obtain the dynamic response of the impeller system and / or tower system in the previous iteration step in the current time step, input the external load of the current time step and the dynamic response of the impeller system or tower system in the previous iteration step into the external force calculation formula, i.e., formula (13), to obtain the external force on the tower system or impeller system in the current iteration step;

[0093] Compare the external force on the tower body system or impeller system in the current iteration step with the external force on the tower body system or impeller system in the previous iteration step, and determine whether the convergence condition is met. The convergence condition in this embodiment specifically refers to that the difference between the generalized force calculated in the previous iteration step and the current iteration step is less than a certain error limit, which is used to determine whether the iteration has converged or whether the result is less than a certain error;

[0094] If the convergence condition is not met, the dynamic response of the tower system in the current iteration step is calculated by using the OpenSEES solver according to the external force of the tower system in the current iteration step, or the dynamic response of the impeller system in the current iteration step is calculated by using the dynamic solver according to the external force of the impeller system in the current iteration step, and then the external load of the current time step and the dynamic response of the tower system or impeller system in the current iteration step are input into the external force calculation formula of formula (13) to obtain the external force of the impeller system or tower system in the current iteration step. Finally, the dynamic response of the impeller system in the current iteration step is calculated by using the dynamic solver according to the external force of the impeller system in the current iteration step, or the dynamic response of the tower system in the current iteration step is calculated by using the OpenSEES solver according to the external force of the tower system in the current iteration step;

[0095] If the convergence condition is met, enter the next time step and calculate the iterative initial value of the next time step.

[0096] like Figure 5 As shown, in the actual iterative solution, for each time step, it will be decomposed into multiple sub-time steps for iteration to reduce the difficulty of solution caused by the sudden change of system response. At the same time, the wind turbine power equation established by formula (2) is used to establish an integrated wind turbine dynamic model for synchronous solution. The expression of the integrated model and its expanded formula are shown in formulas (2) to (8). The system response solved by it is used as the initial value of each iteration to optimize the selection of iteration value and reduce the number of iterations. Since the model introduces the properties of mixed tower nonlinearity, the stiffness of the tower system may change, resulting in a gap between the tower body in the integrated model and the tower body in the mixed model, which in turn generates errors in the calculation, making the selection of initial values ​​meaningless. Therefore, after each time step, the finite element solver OpenSEES will be used to solve the stiffness value of the tower body, so as to update the last two values ​​of the diagonal in the stiffness matrix of formula (5) of the integrated model, reduce the gap between the two models, optimize the selection of initial values, and improve the solution speed and accuracy. Therefore, when calculating the initial value of the iteration of the next time step, it includes:

[0097] The OpenSEES solver is used to solve the stiffness value of the tower system and update it to the preset wind turbine dynamics model. The updated wind turbine dynamics model is solved to obtain the iterative initial value of the dynamic response of the impeller system and the tower system in the next time step.

[0098] Embodiment 2

[0099] This embodiment provides a hybrid tower wind turbine dynamic response calculation system, including a microprocessor and a computer storage medium connected to each other, wherein the microprocessor is programmed or configured to execute the hybrid tower wind turbine dynamic response calculation method described in the first embodiment.

[0100] like Figure 6 As shown, the hybrid tower wind turbine dynamic response calculation system in this embodiment specifically includes a file input and output module, a core calculation module, an OpenSEES interaction module, a Python extension module, and a user visualization interface. The file input and output module, the core calculation module, and the OpenSEES interaction module are the calculation part, while the Python extension module and the user visualization interface are the interaction part.

[0101] The file input and output module is responsible for managing the input of calculation parameters and the output of calculation results. Since wind turbine calculation involves the coupling of multiple modules, different modules may require parameter files of different formats and types. In order to simplify the parameter input and output process, this module establishes a unified API input and output interface based on the Json file format. The core calculation module is the core of the software and is responsible for the actual calculation of the dynamic response of the wind turbine. It includes the simulation of random wind fields, aerodynamic calculations, and structural multi-body dynamics simulation calculations, which can efficiently and accurately simulate the dynamic response of wind turbines. The OpenSEES interactive module controls the finite element software OpenSEES and handles tasks such as external force input and acquisition of structural responses. The design of this module enables the software to seamlessly connect with OpenSEES, thereby utilizing its powerful finite element analysis capabilities.

[0102] The Python sample code for the core calculation module to perform wind field calculation in this embodiment is as follows:

[0103]

[0104] When calculating the wind field, you can create an object for storing wind field calculation parameters through the class "WindStore", and use the "FileIO" module to read the default wind field calculation parameters from the template file, such as average wind speed, turbulence intensity, wind field grid size, and number of grid points. In addition, you can also set parameters such as calculation duration and time step to control the simulation process. After reading the parameters in the template file, you can directly access and modify the variables in the object, and use the "AddSample" member function to sample and calculate certain parameters generated by the wind field. After defining and modifying the wind field generation parameters, you can pass them into the solver and specify the output file and the number of parallel threads for calculation.

[0105] The Python sample code for solving the dynamic response of the wind turbine by the core calculation module in this embodiment is as follows:

[0106]

[0107] When solving the dynamic response of a wind turbine, when calculating the structural response, it is necessary to specify the result file of the wind field calculation, the aerodynamic solution parameters, the load processor, the solver (multi-body dynamics solver and hybrid model solver), and the result output processor. The aerodynamic solution parameter class is similar to the wind field calculation parameter class. Data can be read from the template and modified and sampled. The load processor is divided into a common aerodynamic load processor and a seismic load processor for calculating seismic loads.

[0108] In multibody dynamics and hybrid model simulation, different solvers have different input parameters. Multibody dynamics solvers do not require specific parameters, while hybrid model solvers require detailed configuration, including defining OpenSEES model files and specifying parameters such as solution substeps and maximum number of iterations. The setting of these parameters has a direct impact on the accuracy of the control solution process and results. Both solvers need to specify the structural system matrix for multibody dynamics calculations. The structural system matrix is ​​the core of multibody dynamics calculations, which defines the system's mass, damping, and stiffness. You can import a pre-calculated structural system matrix file using the "SetMKCFromFile" command. Or you can use the "SetMKCFromFunc" command to specify a function to dynamically calculate the system matrix. The use of specified functions increases the flexibility of program use, allowing users to choose the most appropriate method to define the system matrix according to their needs. Custom functions can use the "@cfunc" decorator of Python's "numba" extension library to convert Python functions into a form that can be called by C language.

[0109] An example of the system matrix calculation function of this embodiment is as follows:

[0110]

[0111] The system matrix calculation function uses "@cfunc" to decorate the Python function and convert the incoming parameters into data types that Python can handle.

[0112] After defining and writing the system matrix calculation function, the system matrix function input example is as follows:

[0113] solver=SolverHandle.SolverHandle2.Create(dt)

[0114] void_ptr=SolverHandle.VoidPointer()

[0115] void_ptr.SetPtr(c_solve.address)

[0116] solver.SetMKCFromFunc(void_ptr, 0.1, 8)

[0117] When the system matrix function is passed in, the function pointer can be converted into a typeless pointer through the "VoidPointer" module and transferred into the solver.

[0118] For the hybrid solver, you can also execute a single Tcl statement to pass parameters from Python to Tcl. The following is an example of executing a Tcl statement:

[0119] solver.evalTclLine(′wipe′)

[0120] solver.evalTclLiine(′setZY_EXTEND_CURRENT_ID{}′.format(index))

[0121] solver.evalTclLine(′set ZY_EXTEND_CURRENT_EC{}′.format(index))

[0122] solver.evalTclLine(′set ZY_EXTEND_NODE_HEIGHT_LIST[list{}]′.format(″.join(map(str, section_h))))

[0123] solver.evalTclLine(′set ZY_EXTEND_NODE_NUM{}′.format(len(section_h)))

[0124] solver.evalTclLine(′set ZY_EXTEND_EIY_LIST[list{}]′.format(′′.join(map(str, section_Stiffness))))

[0125] solver.evalTclLine(′set ZY_EXTEND_EIZ_LIST[list{}]′.format(′′.join(map(str, section_Stiffness))))

[0126] solver.evalTclLine(′set ZY_EXTEND_EA_LIST[list{}]′.format(′′.join(map(str, section_EA))))

[0127] solver.evalTclLine(′set ZY_EXTEND_GJ_LIST[list{}]′.format(′.join(map(str, section_GJ))))

[0128] solver.evalT(lLine(′set ZY_EXTEND_MASS_LIST[list{}]′.format(′′.join(map(str, section_MassDen)))

[0129] When executing TCL statements, parameters such as section stiffness and section mass density are injected into the finite element model in OpenSEES in Python.

[0130] In simulation analysis, the management and optimization of result output is an important part of improving computational efficiency and data processing efficiency. In hybrid model simulation, especially when OpenSEES models are involved, the output parameters can be specified using the "OPS" prefix to ensure accurate data output. For example, as shown in the Python example code for solving the dynamic response of a wind turbine, in "OPS:FIBER:ele-time-ele 10section 1fiberData2", "OPS" ensures that the output is the data of the OpenSEES model, "FIBER" is the name of the output result, and the subsequent commands are consistent with the commands for setting the result recorder in the OpenSEES Tcl language.

[0131] In summary, the present invention proposes a hybrid tower wind turbine dynamic response calculation method and system, decouples the hybrid tower wind turbine into an impeller system and a tower system, considers the interaction between the two subsystems for coupling calculation, completes the data exchange between the two systems in each time step of the coupling calculation through the secondary development of OpenSEES, and completes the force balance between the two systems through iteration to solve the accurate system response. It has the following advantages:

[0132] 1. The finite element method is used to calculate the steel-reinforced concrete hybrid tower, which can take into account the complexity of the tower section and the complexity of the tower material, and can also consider the influence of prestressed steel bars on the tower.

[0133] 2. The tower model and the upper part model of the wind turbine are analyzed independently by using a subsystem approach, which can take into account the interaction between the impeller and the tower model and reflect it in each analysis time step. At the same time, different calculation methods are used for systems of different complexity, which improves the efficiency of wind turbine dynamic response simulation.

[0134] 3. Using the subsystem method to decouple the impeller system and the tower system is conducive to considering more complex tower models.

[0135] The above is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention belong to the protection scope of the present invention. It should be pointed out that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the present invention should also be regarded as the protection scope of the present invention.

Claims

1. A method for calculating the dynamic response of a hybrid tower wind turbine, characterized in that: The following steps are involved: The decoupled hybrid tower wind turbine comprises an impeller system and a tower system, wherein the impeller system comprises blades and a nacelle, and the tower system comprises a supporting tower body; Considering the interaction between the impeller system and the tower system, coupling calculation is performed to obtain the dynamic response of the impeller system and the tower system. A dynamic solver is used when performing multi-flexible body system calculation on the impeller system. Data exchange between the impeller system and the tower system is performed at each solution time step of the coupling calculation. During the coupling calculation, multi-flexible body system calculation is performed on the impeller system, and finite element method calculation is performed on the tower system. When the finite element method calculation is performed on the tower system, an OpenSEES solver is used. When considering the interaction between the impeller system and the tower system, the coupling calculation includes the steps of performing iterative coupling calculation, including: Obtain the dynamic response of the impeller system and / or tower system in the previous iteration step in the current time step, input the external load of the current time step and the dynamic response of the impeller system or tower system in the previous iteration step into the external force calculation formula, and obtain the external force exerted on the tower system or impeller system in the current iteration step; Compare the external force on the tower system or impeller system in the current iteration step with the external force on the tower system or impeller system in the previous iteration step, and determine whether the convergence condition is met; If the convergence condition is not met, the OpenSEES solver is used to calculate the dynamic response of the tower system in the current iteration step according to the external force applied to the tower system in the current iteration step, or the dynamics solver is used to calculate the dynamic response of the impeller system in the current iteration step according to the external force applied to the impeller system in the current iteration step, and then the external load of the current time step and the dynamic response of the tower system or impeller system in the current iteration step are input into the external force calculation formula to obtain the external force applied to the impeller system or tower system in the current iteration step, and finally the dynamics solver is used to calculate the dynamic response of the impeller system in the current iteration step according to the external force applied to the impeller system in the current iteration step, or the OpenSEES solver is used to calculate the dynamic response of the tower system in the current iteration step according to the external force applied to the tower system in the current iteration step; If the convergence condition is met, enter the next time step and calculate the iterative initial value of the next time step.

2. The method for calculating the dynamic response of a hybrid tower wind turbine according to claim 1, characterized in that: The dynamics solver uses the Euler-Lagrange equation to derive the dynamics equation; the OpenSEES solver uses OpenSEES software to perform modeling and simulation.

3. The method for calculating the dynamic response of a hybrid tower wind turbine according to claim 1, characterized in that: The convergence condition is specifically: the difference between the external force applied to the tower body system or the impeller system in the current iteration step and the external force applied to the tower body system or the impeller system in the previous iteration step is less than a specified error limit.

4. The method for calculating the dynamic response of a hybrid tower wind turbine according to claim 1, characterized in that: When calculating the initial value of the iteration for the next time step, include: The OpenSEES solver is used to solve the stiffness value of the tower system and update it to the preset wind turbine dynamics model. The updated wind turbine dynamics model is solved to obtain the iterative initial value of the dynamic response of the impeller system and the tower system in the next time step.

5. The method for calculating the dynamic response of a hybrid tower wind turbine according to claim 1, characterized in that: Before obtaining the dynamic response of the impeller system and / or tower system in the previous iteration step in the current time step, the step of calculating the external load of the previous time step is also included, including: Under the action of the actual wind field, the blade element momentum theory is used to calculate the wind load on the blades of the impeller system, and the generalized external force of each degree of freedom of the impeller system and the tower system is calculated using the principle of virtual work.

6. The method for calculating the dynamic response of a hybrid tower wind turbine according to claim 1, characterized in that: When using the dynamics solver and the OpenSEES solver, the calculation formula is as follows: in, is the dynamics solver, For the OpenSEES solver, is the mass matrix of the blades of the impeller system, are the external load forces of the impeller system and the tower system respectively, is the generalized force generated by the tower system movement on the impeller system, is the generalized force generated by the impeller system movement on the tower system, are the displacement, velocity and acceleration variables in the dynamic response of the tower system, are the displacement, velocity and acceleration variables in the dynamic response of the impeller system, They are the damping and stiffness matrices of each degree of freedom of the blades of the impeller system.

7. The method for calculating the dynamic response of a hybrid tower wind turbine according to claim 6, characterized in that: The external force calculation formula is as follows: in, and is the generalized force generated by the tower system movement on the impeller system, and is the generalized force generated by the impeller system on the tower system. and writing: in, are the mass, damping and stiffness matrices of the six degrees of freedom of the blades of the impeller system, are the mass, damping and stiffness matrices of the two degrees of freedom at the top of the tower system.

8. A hybrid tower wind turbine dynamic response calculation system, characterized in that: The invention comprises a microprocessor and a computer storage medium connected to each other, wherein the microprocessor is programmed or configured to execute the hybrid tower wind turbine dynamic response calculation method according to any one of claims 1 to 7.

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