Cascade extension type simulation method for wind turbine generator transmission chain

Abstract

The invention provides a cascade expansion type simulation method for a wind turbine generator transmission chain, and the method comprises the steps: constructing a wind turbine generator complete machine first-stage operation dynamic simulation model, and a transmission chain multi-body dynamics second-stage operation dynamic simulation model which comprises a gearbox multi-body dynamics model, a coupler model and a generator multi-body dynamics model; the wind turbine generator complete machine first-stage operation dynamic simulation model outputs standard values of total aerodynamic torque and generator electromagnetic torque to the transmission chain multi-body dynamics second-stage operation dynamic simulation model based on an input three-dimensional turbulence wind field; the gearbox multi-body dynamic model outputs vibration characteristics and load characteristics of all parts in the gearbox based on the total aerodynamic torque and the electromagnetic torque of the generator; and the generator multi-body dynamic model outputs an actual value of the electromagnetic torque of the generator based on the standard value of the electromagnetic torque of the generator and the rotor angular velocity of the generator. Through the method, the simulation effects of the gearbox multi-body dynamic model and the generator multi-body dynamic model are improved.

Description

Technical Field

[0001] The present application relates to the technical field of wind turbine simulation, and in particular to a cascade expansion simulation method for a wind turbine transmission chain. Background Art

[0002] A wind turbine (i.e., wind power generator) is a renewable energy power generation device that can convert wind energy into electrical energy. At present, when studying wind turbines, a complete model of the wind turbine is usually established, or a simulation model is established for each component in the wind turbine.

[0003] The wind turbine transmission chain (i.e., gearbox and generator) is a part of the wind turbine. In the prior art, when simulating the wind turbine transmission chain, preset parameters (i.e., given values) are usually input into the wind turbine transmission chain simulation model, which makes it difficult to truly reflect the working environment of the gearbox and generator, resulting in poor simulation effect of the wind turbine transmission chain. Summary of the invention

[0004] In view of this, the purpose of the present application is to provide a cascaded expansion simulation method for a wind turbine transmission chain, by using the output of the first-level operation dynamic simulation model of the wind turbine as a whole to drive the operation of the transmission chain multi-body dynamics second-level operation dynamic simulation model, so that the gearbox multi-body dynamics model and the generator multi-body dynamics model can operate in a relatively real working environment, which is beneficial to improve the simulation effect of the gearbox multi-body dynamics model and the generator multi-body dynamics model.

[0005] In a first aspect, an embodiment of the present application provides a cascade expansion simulation method for a wind turbine transmission chain, the method comprising:

[0006] Constructing a first-level dynamic operation simulation model of the wind turbine as a whole unit, and constructing a second-level dynamic operation simulation model of the transmission chain multi-body dynamics; wherein the second-level dynamic operation simulation model of the transmission chain multi-body dynamics includes a sequentially linked gearbox multi-body dynamics model, a coupling model, and a generator multi-body dynamics model;

[0007] The first-level operation dynamic simulation model of the wind turbine set and the second-level operation dynamic simulation model of the transmission chain multi-body dynamics are jointly operated, so that the first-level operation dynamic simulation model of the wind turbine set outputs standard values ​​of the total aerodynamic torque and the electromagnetic torque of the generator to the second-level operation dynamic simulation model of the transmission chain multi-body dynamics based on the input three-dimensional turbulent wind field, so as to drive the second-level operation dynamic simulation model of the transmission chain multi-body dynamics to operate;

[0008] During the operation of the transmission chain multi-body dynamics secondary operation dynamic simulation model, the gearbox multi-body dynamics model outputs the vibration characteristics and load characteristics of each component in the gearbox based on the input total aerodynamic torque and the generator electromagnetic torque obtained from the generator multi-body dynamics model through the coupling model; and the generator multi-body dynamics model outputs the actual value of the generator electromagnetic torque based on the input standard value of the generator electromagnetic torque and the rotor angular velocity of the generator obtained from the gearbox multi-body dynamics model through the coupling model.

[0009] In combination with the first aspect, the embodiment of the present application provides a first possible implementation of the first aspect, wherein the process of constructing the multi-body dynamics model of the gearbox includes:

[0010] Constructing a simulation structure of the multi-body dynamics model of the gearbox; wherein the simulation structure of the multi-body dynamics model of the gearbox includes a gearbox housing, a primary planetary gear train, a secondary planetary gear train, a tertiary parallel gear train, an intermediate shaft, a high-speed shaft and corresponding bearings;

[0011] Based on a preset total transmission ratio, determining the transmission ratio of each gear in the primary planetary gear train, the secondary planetary gear train and the tertiary parallel gear train, so that the transmission ratio of each gear in the gearbox satisfies the total transmission ratio;

[0012] Selecting corresponding materials for various components in the gearbox multi-body dynamics model;

[0013] Verify the gear strength, shaft strength and bearing life in the gearbox multi-body dynamics model to determine whether the simulated gearbox multi-body dynamics model meets the requirements;

[0014] The simulated gearbox multi-body dynamics model that meets the requirements is determined as the constructed gearbox multi-body dynamics model.

[0015] In combination with the first possible implementation of the first aspect, the embodiment of the present application provides a second possible implementation of the first aspect, wherein the process of constructing the generator multi-body dynamics model includes:

[0016] Constructing a simulation structure of the generator multi-body dynamics model; wherein the simulation structure of the generator multi-body dynamics model includes a stator core, a rotor core, a stator winding, a rotor winding, and a main shaft;

[0017] Select corresponding materials for the stator core, the rotor core, the stator winding, the rotor winding, and the main shaft respectively;

[0018] Performing torsional strength check, bending strength check and combined stress check on the main shaft to determine whether the material selected for the generator multi-body dynamics model can meet the strength check requirements;

[0019] When the material selected for the generator multi-body dynamics model can meet the requirements of strength verification, constructing the coupling model according to the diameter of the main shaft;

[0020] Wherein, constructing the coupling model according to the diameter of the main shaft includes:

[0021] Determining the parameters of the coupling model according to the diameter of the main shaft and the diameter of the high-speed shaft to construct a simulation structure of the coupling model;

[0022] Selecting a corresponding material for the coupling model;

[0023] Performing torsional strength check, bending strength check, and combined stress check on the coupling model to determine whether the material selected for the coupling model meets the strength check requirements;

[0024] When the material selected for the coupling model meets the requirements of strength verification, the coupling model is used to connect the main shaft with the high-speed shaft in the gearbox multi-body dynamics model.

[0025] In combination with the first possible implementation of the first aspect, the embodiment of the present application provides a third possible implementation of the first aspect, wherein the primary planetary gear train includes a low-speed shaft, a sun gear, a plurality of planetary gears, and an inner gear ring; the secondary planetary gear train includes a secondary planet carrier, a sun gear, a plurality of planetary gears, and an inner gear ring; the three-stage parallel gear train includes a three-stage large gear and a three-stage small gear;

[0026] The inner gear ring in the first-stage planetary gear train and the inner gear ring in the second-stage planetary gear train are hinged to the gearbox housing, and the gearbox housing is hinged to the low-speed shaft, the second-stage planetary carrier, the intermediate shaft, and the high-speed shaft respectively through spring damping force elements;

[0027] In the primary planetary gear train, a plurality of planetary gears are hinged to the low-speed shaft via a spring damping force element, a plurality of planetary gears are also respectively connected to the sun gear and the inner gear ring via a spring damping force element, and the sun gear is also hinged to the secondary planet carrier;

[0028] In the secondary planetary gear system, the secondary planet carrier is hinged to the multiple planetary gears through a spring damping force element, and the multiple planetary gears are also respectively connected to the sun gear and the inner gear ring through a spring damping force element;

[0029] In the three-stage parallel gear train, the three-stage large gear is connected to the three-stage small gear through a spring damping force element; the intermediate shaft is respectively articulated with the three-stage small gear and the sun gear in the two-stage planetary gear train; the high-speed shaft is also articulated with the three-stage small gear.

[0030] In combination with the first possible implementation manner of the first aspect, the embodiment of the present application provides a fourth possible implementation manner of the first aspect, wherein the checking of the gear strength, shaft strength and bearing life in the gearbox multi-body dynamics model to determine whether the simulated gearbox multi-body dynamics model meets the requirements includes:

[0031] For each gear in the multi-body dynamics model of the gearbox, the tooth root bending strength and the tooth surface contact strength of the gear are calculated, and when the tooth root bending strength of the gear is less than the preset allowable bending strength, and the tooth surface contact strength is less than the preset allowable contact strength, it is determined that the gear meets the requirements;

[0032] For each shaft in the multi-body dynamics model of the gearbox, the shear strength, bending strength and combined stress of the shaft are calculated. When the shear strength of the shaft is greater than the preset allowable shear stress, the bending strength is greater than the preset bending strength, and the combined stress is greater than the preset allowable combined stress, it is determined that the shaft meets the requirements;

[0033] For the bearing in the multi-body dynamics model of the gearbox, the rated dynamic load and equivalent load of the bearing are calculated, and the bearing life of the bearing is determined according to the rated dynamic load and the equivalent load, and when the bearing life meets the preset bearing duration, it is determined that the bearing meets the requirements;

[0034] When each gear, shaft and bearing in the gearbox multi-body dynamics model meets the requirements, it is determined that the gearbox multi-body dynamics model meets the requirements.

[0035] In combination with the first aspect, the embodiment of the present application provides a fifth possible implementation of the first aspect, wherein the method is applied to a cascade expansion simulation system of a wind turbine transmission chain; the cascade expansion simulation system of the wind turbine transmission chain includes a first server, a generator, and a discriminator; the three-dimensional turbulent wind field is generated by a simulated inflow wind model;

[0036] After constructing a first-level dynamic simulation model of the wind turbine set and a second-level dynamic simulation model of the transmission chain multi-body dynamics, the method further includes:

[0037] The simulated inflow wind model, the first-level operation dynamic simulation model of the wind turbine set and the second-level operation dynamic simulation model of the transmission chain multi-body dynamics are deployed in a first server, and respective computing resources are allocated to the inflow wind model, the first-level operation dynamic simulation model of the wind turbine set and the second-level operation dynamic simulation model of the transmission chain multi-body dynamics in the first server, so that the inflow wind model, the first-level operation dynamic simulation model of the wind turbine set and the second-level operation dynamic simulation model of the transmission chain multi-body dynamics are respectively operated using the computing resources allocated to them, and during the operation of the inflow wind model, the first-level operation dynamic simulation model of the wind turbine set and the second-level operation dynamic simulation model of the transmission chain multi-body dynamics, whether the inflow wind model, the first-level operation dynamic simulation model of the wind turbine set and the second-level operation dynamic simulation model of the transmission chain multi-body dynamics can be tested;

[0038] After testing that the inflow wind model, the first-level dynamic operation simulation model of the wind turbine set and the second-level dynamic operation simulation model of the transmission chain multi-body dynamics can operate normally, using the trained generator to generate a plurality of simulated wind condition data of the wind turbine set;

[0039] Using the trained discriminator to judge the authenticity of each of the simulated wind condition data generated by the generator, remove the simulated wind condition data that does not meet the authenticity requirement, and retain the simulated wind condition data that meets the authenticity requirement;

[0040] The simulated wind condition data that meet the authenticity requirements are clustered to group the simulated wind condition data with similar wind conditions into one category, thereby obtaining the simulated wind condition data corresponding to different wind conditions.

[0041] In combination with the fifth possible implementation of the first aspect, the embodiment of the present application provides a sixth possible implementation of the first aspect, wherein the cascade expansion simulation system of the wind turbine transmission chain further includes a host computer and a second server, and the method further includes:

[0042] Deploy the inflow wind model to the host computer, and deploy the first-level dynamic operation simulation model of the wind turbine set and the second-level dynamic operation simulation model of the transmission chain multi-body dynamics to the second server;

[0043] Sending the simulated wind condition data corresponding to different wind conditions to the host computer, so that the host computer inputs the simulated wind condition data into the inflow wind model respectively, and outputs the three-dimensional turbulent wind field corresponding to the simulated wind condition data through the inflow wind model;

[0044] The method is to enable the wind turbine set first-level operation dynamic simulation model to output the standard values ​​of the total aerodynamic torque and the electromagnetic torque of the generator to the transmission chain multi-body dynamics second-level operation dynamic simulation model based on the input three-dimensional turbulent wind field, so as to drive the transmission chain multi-body dynamics second-level operation dynamic simulation model to operate, including:

[0045] The three-dimensional turbulent wind field corresponding to the simulated wind condition data output by the inflow wind model is transmitted to the second server through the host computer, so that the second server inputs the three-dimensional turbulent wind field corresponding to the simulated wind condition data into the first-level operation dynamic simulation model of the wind turbine set;

[0046] The wind turbine set first-level operation dynamic simulation model outputs the standard values ​​of the total aerodynamic torque and the electromagnetic torque of the generator corresponding to the simulated wind condition data to the transmission chain multi-body dynamics second-level operation dynamic simulation model based on the three-dimensional turbulent wind field corresponding to the input simulated wind condition data, so as to drive the transmission chain multi-body dynamics second-level operation dynamic simulation model to operate;

[0047] The method further comprises:

[0048] Collecting vibration characteristics and load characteristics of each component in the gearbox corresponding to each simulated wind condition data;

[0049] Using the vibration characteristics and load characteristics of each component in the gearbox corresponding to each of the collected simulated wind condition data to train a neural network model of the gearbox, to obtain a trained neural network model of the gearbox;

[0050] The gearbox neural network model is deployed to the second server, and the gearbox multi-body dynamics model deployed in the second server is replaced by the gearbox neural network model.

[0051] In combination with the first aspect, the embodiment of the present application provides a seventh possible implementation of the first aspect, wherein the first-level dynamic simulation model of the wind turbine unit includes: a pneumatic system finite element model, a tower finite element model, a pitch system lumped parameter model, a transmission system lumped parameter model, a generator lumped parameter model, a three-phase power grid, a torque controller, a pitch controller, a machine-side converter, and a grid-side converter;

[0052] During the operation of the first-level dynamic simulation model of the wind turbine set, the aerodynamic system finite element model is used to receive the three-dimensional turbulent wind field, and receive the actual value of the pitch angle sent by the variable pitch system lumped parameter model, and send the total aerodynamic torque to the transmission system lumped parameter model, send the component of the total aerodynamic torque along the radial direction of the blade to the tower finite element model, and receive the aerodynamic force on the tower top node sent by the tower finite element model, and calculate the forward and backward thrust of the aerodynamic system on the tower top according to the component of the total aerodynamic torque along the radial direction of the blade and the aerodynamic force on the tower top node;

[0053] The tower finite element model is used to receive the three-dimensional turbulent wind field and the component of the total aerodynamic moment along the radial direction of the blade sent by the aerodynamic system finite element model, and calculate the forward and backward thrust of the aerodynamic system on the tower top according to the component of the total aerodynamic moment along the radial direction of the blade and the aerodynamic force received by the tower top node;

[0054] The transmission system lumped parameter model is used to receive the generator electromagnetic torque sent by the generator lumped parameter model, receive the total aerodynamic torque sent by the aerodynamic system finite element model, and send the wind wheel rotor speed to the pitch controller, send the generator rotor angular velocity to the torque controller, send the generator rotor angular velocity to the generator lumped parameter model, and send the total aerodynamic torque to the gearbox multi-body dynamics model;

[0055] The generator lumped parameter model is used to send the actual value of the electromagnetic torque of the generator to the transmission system lumped parameter model, and receive the rotor angular velocity of the generator sent by the transmission system lumped parameter model and the q-axis current of the generator rotor sent by the machine-side converter;

[0056] The pitch system lumped parameter model is used to send the actual value of the pitch angle to the aerodynamic system finite element model, and receive the standard value of the pitch angle sent by the pitch controller;

[0057] The pitch controller is used to receive the one-dimensional scalar wind speed, receive the wind wheel rotor speed from the transmission system lumped parameter model, and send the standard value of the pitch angle to the pitch system lumped parameter model;

[0058] The torque controller is used to receive the rotor angular velocity of the generator sent by the lumped parameter model of the transmission system, and to send the standard value of the electromagnetic torque of the generator to the machine-side converter and to send the standard value of the electromagnetic torque of the generator to the multi-body dynamics model of the generator;

[0059] The machine-side converter is used to receive the DC bus voltage provided by the grid-side converter, receive the standard value of the generator electromagnetic torque sent by the torque controller, and send the q-axis current of the generator rotor to the generator lumped parameter model;

[0060] The grid-side converter is used to provide a DC bus voltage to the generator-side converter.

[0061] In combination with the seventh possible implementation of the first aspect, the embodiment of the present application provides an eighth possible implementation of the first aspect, wherein the pneumatic system finite element model is constructed by the following method:

[0062] For each wind rotor blade in the wind turbine generator set, determine the position of each blade node in the wind rotor blade according to the first preset node number and the length of the wind rotor blade;

[0063] Constructing an aerodynamic force expression for a blade node; wherein the aerodynamic force expression for a blade node is used to output the aerodynamic force of the blade node for each blade node in the wind rotor blade according to the input air density and the wind speed, force area, lift coefficient, drag coefficient, and windward angle at the blade node;

[0064] Constructing an aerodynamic torque expression; wherein the aerodynamic torque expression is used to output the aerodynamic torque of the blade node according to the input aerodynamic force of the blade node and the distance between the blade node and the blade root of the wind rotor blade;

[0065] Constructing a total aerodynamic torque expression; wherein the total aerodynamic torque expression is used to accumulate and sum the aerodynamic torques of all blade nodes on all the wind rotor blades to obtain the total aerodynamic torque of all the wind rotor blades;

[0066] Constructing a blade root bending moment expression; wherein the blade root bending moment expression is used to calculate the blade root bending moment of all the wind rotor blades according to the aerodynamic force of each blade node in all the wind rotor blades and the distance between each blade node in each of the wind rotor blades and the blade root of the wind rotor blade; the aerodynamic system node finite element model is composed of the total aerodynamic moment expression and the blade root bending moment expression;

[0067] The tower finite element model is constructed by the following method:

[0068] For the tower in the wind turbine generator set, determining the position of each tower node in the tower according to the second preset node number and the length of the tower;

[0069] Constructing an aerodynamic force expression for a tower node; wherein the aerodynamic force expression for a tower node is used to output the aerodynamic force of the tower node for each tower node according to the input air density, the drag coefficient of the tower, and the scalar wind speed and the windward area at the tower node;

[0070] Based on the mass matrix, damping matrix and stiffness matrix of the tower, a finite element model of the tower is constructed; the finite element model of the tower is used to calculate the vibration displacement of each tower node according to the aerodynamic force of each tower node;

[0071] The generator lumped parameter model is constructed by the following method:

[0072] For a generator stator and a generator rotor in the wind turbine generator set, obtaining a d-axis current and a q-axis current of the generator stator and the generator rotor in a dq rotating coordinate system;

[0073] In the dq rotating coordinate system, a flux equation of the generator stator is constructed; wherein the flux equation of the generator stator is used to calculate the flux of the generator stator according to the self-inductance of the generator stator, the mutual inductance between the generator stator and the generator rotor, and the d-axis current and q-axis current of the generator stator and the generator rotor;

[0074] Constructing the lumped parameter model of the generator; wherein the lumped parameter model of the generator is used to calculate the electromagnetic torque of the generator according to the pole pair number of the generator and the flux linkage of the stator of the generator;

[0075] The variable pitch system lumped parameter model is used to calculate the actual value of the pitch angle according to the input standard value of the pitch angle;

[0076] The transmission system lumped parameter model is used to calculate the wind wheel rotor speed and the generator rotor speed according to the input wind wheel aerodynamic torque and generator electromagnetic torque.

[0077] In combination with the seventh possible implementation of the first aspect, the embodiment of the present application provides a ninth possible implementation of the first aspect, wherein, when the one-dimensional scalar wind speed is greater than the rated wind speed, the torque controller calculates the ratio of the rated power of the generator to the rotor speed of the generator to obtain a standard value of the electromagnetic torque of the generator; the machine-side converter calculates the q-axis component of the rotor current according to the standard value of the electromagnetic torque of the generator calculated by the torque controller; the generator lumped parameter model calculates the actual value of the electromagnetic torque of the generator according to the q-axis component of the rotor current calculated by the machine-side converter;

[0078] When the one-dimensional scalar wind speed is greater than the rated wind speed, the pitch controller uses the PI control strategy to calculate the product of the wind rotor speed and the gearbox speed ratio according to the received wind rotor speed, and calculates the difference between the product and the rated speed of the generator rotor. When the difference is not equal to 0, the pitch controller calculates the standard value of the pitch angle according to the received wind rotor speed and the rated speed of the generator rotor; the pitch system lumped parameter model calculates the actual value of the pitch angle according to the standard value of the pitch angle calculated by the pitch controller; the aerodynamic system finite element model calculates the actual value of the pitch angle according to the standard value of the pitch angle calculated by the pitch system lumped parameter model The actual value of the pitch angle is used to calculate the aerodynamic torque of the wind wheel; the lumped parameter model of the transmission system calculates the aerodynamic torque of the wind wheel calculated by the finite element model of the aerodynamic system, and calculates the speed of the wind wheel rotor; the pitch controller continues to calculate the product of the wind wheel rotor speed and the gear ratio of the gear box according to the received wind wheel rotor speed, and calculates the difference between the product and the rated speed of the generator rotor. When the difference is not equal to 0, the pitch controller continues to calculate the standard value of the pitch angle and subsequent steps according to the received wind wheel rotor speed and the rated speed of the generator rotor, and stops when the difference is equal to 0 to obtain the final wind wheel rotor speed;

[0079] When the one-dimensional scalar wind speed is less than or equal to the rated wind speed, the torque controller calculates the standard value of the electromagnetic torque of the generator according to the OTC torque control strategy; the machine-side converter calculates the q-axis component of the rotor current according to the standard value of the electromagnetic torque of the generator calculated by the torque controller; the generator lumped parameter model calculates the actual value of the electromagnetic torque of the generator according to the q-axis component of the rotor current calculated by the machine-side converter;

[0080] When the one-dimensional scalar wind speed is less than or equal to the rated wind speed, the standard value of the pitch angle output by the pitch controller is equal to 0.

[0081] A cascaded extended simulation method for a wind turbine transmission chain is provided in an embodiment of the present application. By jointly operating a first-level dynamic operation simulation model of the wind turbine as a whole machine and a second-level dynamic operation simulation model of the transmission chain multi-body dynamics, the output of the first-level dynamic operation simulation model of the wind turbine as a whole machine is used as the input of the second-level dynamic operation simulation model of the transmission chain multi-body dynamics, so that the second-level dynamic operation simulation model of the transmission chain multi-body dynamics is simulated based on the simulation results output by the first-level dynamic operation simulation model of the wind turbine as a whole machine. Compared with the second-level dynamic operation simulation model of the transmission chain multi-body dynamics using preset parameters for simulation, in this embodiment, the output of the first-level dynamic operation simulation model of the wind turbine as a whole machine is used to drive the second-level dynamic operation simulation model of the transmission chain multi-body dynamics to run, so that the gearbox multi-body dynamics model and the generator multi-body dynamics model (i.e., the second-level dynamic operation simulation model of the transmission chain multi-body dynamics) can operate in a relatively real working environment, which is beneficial to improving the simulation effect of the gearbox multi-body dynamics model and the generator multi-body dynamics model.

[0082] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, preferred embodiments are specifically cited below and described in detail with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0083] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0084] Figure 1 A flow chart of a cascade expansion simulation method for a wind turbine transmission chain provided in an embodiment of the present application is shown;

[0085] Figure 2 A schematic diagram showing a first-level dynamic simulation model of a wind turbine generator system and a second-level dynamic simulation model of multi-body dynamics of a transmission chain provided in an embodiment of the present application is shown;

[0086] Figure 3 A schematic structural diagram of a gearbox multi-body dynamics model provided in an embodiment of the present application is shown;

[0087] Figure 4 A schematic diagram of a blade node and a tower node of a wind turbine provided in an embodiment of the present application is shown;

[0088] Figure 5 A schematic diagram of a three-dimensional grid of a three-dimensional turbulent wind field provided in an embodiment of the present application is shown;

[0089] Figure 6 A schematic diagram of the operation of a torque controller and a pitch controller provided in an embodiment of the present application is shown. DETAILED DESCRIPTION

[0090] To make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. The components of the embodiments of the present application generally described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the application claimed for protection, but merely represents the selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without making creative work belong to the scope of protection of the present application.

[0091] Considering that when simulating the transmission chain of a wind turbine, preset parameters (i.e., given values) are usually input into the simulation model of the transmission chain of the wind turbine, it is difficult to truly reflect the working environment of the gearbox and the generator, resulting in poor simulation effect of the transmission chain of the wind turbine. Based on this, an embodiment of the present application provides a cascade expansion simulation method for the transmission chain of a wind turbine, which drives the operation of the multi-body dynamics secondary operation dynamic simulation model of the transmission chain by using the output of the first-level operation dynamic simulation model of the whole wind turbine, so that the gearbox multi-body dynamics model and the generator multi-body dynamics model can operate in a relatively real working environment, which is conducive to improving the simulation effect of the gearbox multi-body dynamics model and the generator multi-body dynamics model, which is described below through an embodiment.

[0092] To facilitate understanding of this embodiment, a cascade expansion simulation method for a wind turbine transmission chain disclosed in this embodiment of the present application is first introduced in detail. Figure 1 As shown, the cascade expansion simulation method of the wind turbine transmission chain includes steps S101-S103:

[0093] S101: construct a first-level dynamic operation simulation model of the wind turbine as a whole unit, and construct a second-level dynamic operation simulation model of the transmission chain multi-body dynamics; wherein the second-level dynamic operation simulation model of the transmission chain multi-body dynamics includes a sequentially linked gearbox multi-body dynamics model, a coupling model, and a generator multi-body dynamics model.

[0094] In this embodiment, if Figure 2As shown in the figure, a first-level dynamic simulation model of the whole wind turbine is constructed, and a second-level dynamic simulation model of the multi-body dynamics of the transmission chain is constructed. Among them, the first-level dynamic simulation model of the whole wind turbine is the whole machine simulation model of the wind turbine. The second-level dynamic simulation model of the multi-body dynamics of the transmission chain is the simulation model of the transmission chain in the wind turbine, such as Figure 2 As shown, the transmission chain multi-body dynamics secondary operation dynamic simulation model includes a sequentially linked gearbox multi-body dynamics model, a coupling model, and a generator multi-body dynamics model. Among them, the coupling model is used to connect the gearbox multi-body dynamics model and the generator multi-body dynamics model. The gearbox multi-body dynamics model is a simulation model of the gearbox in the wind turbine, the coupling model is a simulation model of the coupling in the wind turbine, and the generator multi-body dynamics model is a simulation model of the generator in the wind turbine.

[0095] S102: jointly operate the first-level dynamic operation simulation model of the wind turbine set and the second-level dynamic operation simulation model of the transmission chain multi-body dynamics, so that the first-level dynamic operation simulation model of the wind turbine set outputs standard values ​​of the total aerodynamic torque and the electromagnetic torque of the generator to the second-level dynamic operation simulation model of the transmission chain multi-body dynamics based on the input three-dimensional turbulent wind field, so as to drive the operation of the second-level dynamic operation simulation model of the transmission chain multi-body dynamics.

[0096] In this embodiment, if Figure 2 As shown in the figure, the three-dimensional turbulent wind field is input into the first-level dynamic simulation model of the wind turbine through the constructed inflow wind model. The three-dimensional turbulent wind field is used to characterize the wind conditions when the wind turbine is running. Based on the input three-dimensional turbulent wind field, the first-level dynamic simulation model of the wind turbine outputs the total aerodynamic torque T to the gearbox multi-body dynamics model in the second-level dynamic simulation model of the transmission chain multi-body dynamics. r , and output the standard value of the generator electromagnetic torque to the generator multi-body dynamics model in the secondary operation dynamic simulation model of the transmission chain multi-body dynamics This drives the gearbox multi-body dynamics model and the generator multi-body dynamics model in the secondary operation dynamic simulation model of the transmission chain multi-body dynamics.

[0097] S103: During the operation of the transmission chain multi-body dynamics secondary operation dynamic simulation model, the gearbox multi-body dynamics model outputs the vibration characteristics and load characteristics of each component in the gearbox based on the input total aerodynamic torque and the generator electromagnetic torque obtained from the generator multi-body dynamics model through the coupling model; and the generator multi-body dynamics model outputs the actual value of the generator electromagnetic torque based on the input standard value of the generator electromagnetic torque and the rotor angular velocity of the generator obtained from the gearbox multi-body dynamics model through the coupling model.

[0098] In this embodiment, if Figure 2As shown in the figure, the gearbox multibody dynamics model converts the rotor angular velocity ω of the generator into g The coupling model is sent to the generator multi-body dynamics model, and the generator multi-body dynamics model converts the generator electromagnetic torque T e It is sent to the gearbox multibody dynamics model through the coupling model.

[0099] The multi-body dynamics model of the gearbox is based on the total aerodynamic torque T r , and the generator electromagnetic torque T e , the vibration characteristics and load characteristics of each component in the output gearbox. The generator multi-body dynamics model is based on the standard value of the generator electromagnetic torque and the generator rotor angular velocity ω g , the actual value of the electromagnetic torque of the output generator T e .

[0100] In a possible implementation, the gearbox multi-body dynamics model may be constructed by following the steps S201-S205:

[0101] S201: Constructing a simulation structure of a gearbox multi-body dynamics model; wherein the simulation structure of the gearbox multi-body dynamics model includes a gearbox housing, a primary planetary gear train, a secondary planetary gear train, a tertiary parallel gear train, an intermediate shaft, a high-speed shaft, and corresponding bearings.

[0102] like Figure 3 As shown, the first-stage planetary gear train includes a low-speed shaft, a sun gear, multiple planetary gears, and an inner ring gear; the second-stage planetary gear train includes a second-stage planetary carrier, a sun gear, multiple planetary gears, and an inner ring gear; the third-stage parallel gear train includes three-stage large gears and three-stage small gears; wherein, the inner ring gear in the first-stage planetary gear train and the inner ring gear in the second-stage planetary gear train are hinged to the gear box body, and the gear box body is respectively hinged to the low-speed shaft, the second-stage planetary carrier, the intermediate shaft, and the high-speed shaft through spring damping force elements.

[0103] In the primary planetary gear system, multiple planetary gears are hinged to the low-speed shaft through spring damping force elements, multiple planetary gears are also respectively connected to the sun gear and the inner gear ring through spring damping force elements, and the sun gear is also hinged to the secondary planet carrier;

[0104] In the secondary planetary gear system, the secondary planet carrier is hinged to the multiple planetary gears through spring damping force elements, and the multiple planetary gears are also respectively connected to the sun gear and the inner gear ring through spring damping force elements;

[0105] In the three-stage parallel gear train, the three-stage large gear is connected to the three-stage small gear through a spring damping force element; the intermediate shaft is respectively articulated with the three-stage small gear and the sun gear in the two-stage planetary gear train; the high-speed shaft is also articulated with the three-stage small gear.

[0106] In this embodiment, if Figure 3As shown, there are 5 planetary gears in the first-stage planetary gear train and 5 planetary gears in the second-stage planetary gear train.

[0107] S202: Based on a preset total transmission ratio, determine the transmission ratio of each gear in the primary planetary gear train, the secondary planetary gear train and the tertiary parallel gear train, so that the transmission ratio of each gear in the gearbox meets the total transmission ratio.

[0108] In this embodiment, the total transmission ratio N preset by the gearbox is obtained from the design manual of the actual wind turbine generator set, and the total transmission ratio can be expressed as:

[0109] N=N 1 ×N 2 ×N 3

[0110] Where: N 1 is the transmission ratio of the gears in the primary planetary gear train, N 2 is the transmission ratio of the gears in the secondary planetary gear train, N 3 is the transmission ratio of the gears in the three-stage parallel gear train. 1 、N 2 and N 3 Make sure the gearbox meets the total transmission ratio N.

[0111] S203: Select corresponding materials for each component in the gearbox multibody dynamics model.

[0112] S204: Check the gear strength, shaft strength and bearing life in the gearbox multi-body dynamics model to determine whether the simulated gearbox multi-body dynamics model meets the requirements.

[0113] In this embodiment, when executing step S204, the following steps S2041-S2044 may be specifically performed:

[0114] S2041: For each gear in the gearbox multi-body dynamics model, calculate the tooth root bending strength and tooth surface contact strength of the gear. When the tooth root bending strength of the gear is less than the preset allowable bending strength, and the tooth surface contact strength is less than the preset allowable contact strength, it is determined that the gear meets the requirements.

[0115] In this embodiment, the tooth root bending strength σ of the gear is calculated by the following formula: F :

[0116]

[0117] Among them, F t is the circumferential force of the gear; K A is the applied load factor; K V is the speed coefficient; K Fis the tooth root shape factor; b is the gear width; m n is the normal modulus; Y F is the tooth root stress correction factor.

[0118] The gear tooth surface contact strength σ is calculated by the following formula H :

[0119]

[0120] Among them, d m is the pitch circle diameter; Z E and Z H K is the correction coefficient of tooth surface contact stress; H Load distribution factor between teeth for contact strength calculation.

[0121] In this embodiment, the allowable bending strength is the same as the allowable contact strength, both of which are σ allow , so when σ is satisfied F <σ allow And σ H <σ allow When checking, make sure the gear meets the requirements.

[0122] S2042: For each shaft in the gearbox multi-body dynamics model, the shear strength, bending strength, and combined stress of the shaft are calculated. When the shear strength of the shaft is greater than the preset allowable shear stress, the bending strength is greater than the preset bending strength, and the combined stress is greater than the preset allowable combined stress, the shaft is determined to meet the requirements.

[0123] In this embodiment, the shear strength τ of the shaft is calculated by the following formula:

[0124]

[0125] Where T is the transmitted torque, r is the radius of the shaft, and d is the diameter of the shaft segment.

[0126] The safety factor n of shear strength is calculated by the following formula T :

[0127]

[0128] Among them, τ allow is the allowable shear strength. In order to ensure the shear strength of the shaft, n T ≥1.5.

[0129] In this embodiment, the bending strength σ of the shaft is calculated by the following formula: b :

[0130]

[0131] Among them, Mb is the bending moment; c is the distance from the outer edge of the shaft section to the central axis, and d is the diameter of the shaft.

[0132] The bending strength σ is calculated by the following formula b Safety factor n b :

[0133]

[0134] Among them, σ allow For the allowable bending strength, in order to ensure the bending strength of the shaft, n b ≥1.5.

[0135] In this embodiment, since the shaft is usually subjected to torque and bending moment at the same time, it is necessary to perform a combined stress check. The combined stress σ is calculated by the following formula eq :

[0136]

[0137] The safety factor n of the combined stress is calculated by the following formula eq :

[0138]

[0139] In order to ensure the combined stress of the shaft, n eq ≥1.5.

[0140] S2043: For the bearings in the gearbox multi-body dynamics model, the rated dynamic load and equivalent load of the bearings are calculated, and the bearing life of the bearings is determined based on the rated dynamic load and the equivalent load. When the bearing life meets the preset bearing duration, it is determined that the bearing meets the requirements.

[0141] In this embodiment, the rated dynamic load C of the bearing is calculated by the following formula:

[0142] C = f c ·i·d B 1.8

[0143] Among them, f c is the type and structural coefficient of the bearing, i is the number of rolling elements in the bearing, d B is the inner diameter of the bearing.

[0144] The equivalent load P of the bearing is calculated by the following formula:

[0145] P=X·F r +Y·F a

[0146] Among them, F r is the radial load; Fa is the axial load; X and Y are the radial and axial load factors provided by the bearing manufacturer.

[0147] S2044: When each gear, shaft, and bearing in the gearbox multibody dynamics model meets the requirements, it is determined that the gearbox multibody dynamics model meets the requirements.

[0148] S205: Determine the simulated gearbox multi-body dynamics model that meets the requirements as the constructed gearbox multi-body dynamics model.

[0149] In a possible implementation, the generator multi-body dynamics model is constructed by following the steps S301-S304:

[0150] S301: constructing a simulation structure of a generator multi-body dynamics model; wherein the simulation structure of the generator multi-body dynamics model includes a stator core, a rotor core, a stator winding, a rotor winding, and a main shaft.

[0151] In this embodiment, actual wind turbine generator parameters are obtained from the design manual of the actual wind turbine generator, the geometric shape of the generator multi-body dynamics model is constructed using 3D modeling software, and various parts are combined into an assembly.

[0152] S302: Select corresponding materials for the stator core, the rotor core, the stator winding, the rotor winding, and the main shaft respectively.

[0153] In this embodiment, the materials of the stator core, the rotor core, the stator winding, and the rotor winding are selected based on the specification of the actual generator of the unit.

[0154] S303: Perform torsional strength check, bending strength check, and combined stress check on the main shaft to determine whether the material selected for the generator multi-body dynamics model can meet the strength check requirements.

[0155] In this embodiment, since the materials of the stator core, rotor core, stator winding, and rotor winding in the generator multi-body dynamics model can all be obtained from the specification, and they do not bear the role of transferring loads, only the torsional strength check, bending strength check, and combined stress check are performed on the main shaft of the generator to ensure that the selected materials can meet the strength check requirements.

[0156] S304: When the material selected for the generator multi-body dynamics model can meet the requirements of strength verification, a coupling model is constructed according to the diameter of the main shaft.

[0157] Wherein, when executing step S304 to construct the coupling model according to the diameter of the main shaft, the following steps may be specifically performed:

[0158] S3041: Determine the parameters of the coupling model according to the diameter of the main shaft and the diameter of the high-speed shaft to construct a simulation structure of the coupling model.

[0159] In this embodiment, the parameters of the coupling model are determined according to the diameter of the main shaft in the generator multi-body dynamics model and the diameter of the high-speed shaft in the gearbox multi-body dynamics model, and the geometric shape of the coupling model is constructed using 3D modeling software based on these two parameters.

[0160] S3042: Select the appropriate material for the coupling model.

[0161] S3043: Perform torsional strength check, bending strength check, and combined stress check on the coupling model to determine whether the material selected for the coupling model meets the strength check requirements.

[0162] S3044: Use the coupling model to connect the main shaft to the high-speed shaft in the gearbox multibody dynamics model when the material selected for the coupling model meets the requirements of the strength check.

[0163] In this embodiment, the coupling model is used to connect the gearbox multi-body dynamics model with the generator multi-body dynamics model, and plays a role in load transfer between the two models. The gearbox multi-body dynamics model transmits the rotor angular velocity of the generator to the main shaft of the generator multi-body dynamics model through the coupling model, and the generator multi-body dynamics model transmits the actual value of the electromagnetic torque to the high-speed shaft of the gearbox multi-body dynamics model through the coupling model.

[0164] In a possible implementation, the cascade expansion simulation method of the wind turbine transmission chain is applied to the cascade expansion simulation system of the wind turbine transmission chain; the cascade expansion simulation system of the wind turbine transmission chain includes a first server, a generator, and a discriminator; the three-dimensional turbulent wind field is generated by the simulated inflow wind model;

[0165] After constructing the first-level dynamic simulation model of the wind turbine unit and the second-level dynamic simulation model of the transmission chain multi-body dynamics, the cascade expansion simulation method of the wind turbine transmission chain can also be performed according to the following steps S401-S404:

[0166] S401: deploy the simulated inflow wind model, the first-level operation dynamic simulation model of the wind turbine complete machine, and the second-level operation dynamic simulation model of the transmission chain multi-body dynamics in the first server, and allocate respective computing resources to the inflow wind model, the first-level operation dynamic simulation model of the wind turbine complete machine, and the second-level operation dynamic simulation model of the transmission chain multi-body dynamics in the first server, so that the inflow wind model, the first-level operation dynamic simulation model of the wind turbine complete machine, and the second-level operation dynamic simulation model of the transmission chain multi-body dynamics can be operated using their respective allocated computing resources, and during the operation of the inflow wind model, the first-level operation dynamic simulation model of the wind turbine complete machine, and the second-level operation dynamic simulation model of the transmission chain multi-body dynamics, test whether the inflow wind model, the first-level operation dynamic simulation model of the wind turbine complete machine, and the second-level operation dynamic simulation model of the transmission chain multi-body dynamics can operate normally.

[0167] In this embodiment, after the inflow wind model, the first-level dynamic simulation model of the wind turbine unit and the second-level dynamic simulation model of the transmission chain multi-body dynamics are constructed, they are respectively encapsulated into independent containers through Docker container technology, and the resource allocation between containers is managed using container orchestration tools. CPU cores are allocated to each model container, and computing resources are dynamically allocated according to demand. After the physical field models are separated by containerization technology, the integrated simulation platform can be deployed on a first server (e.g., a single computer or server).

[0168] S402: After the test inflow and outflow wind model, the first-level dynamic simulation model of the wind turbine unit and the second-level dynamic simulation model of the transmission chain multi-body dynamics can operate normally, the trained generator is used to generate simulated wind condition data for multiple wind turbines.

[0169] S403: Use the trained discriminator to judge the authenticity of each simulated wind condition data generated by the generator, remove the simulated wind condition data that does not meet the authenticity requirements, and retain the simulated wind condition data that meets the authenticity requirements.

[0170] In this embodiment, the task of the discriminator is to distinguish the authenticity of the input simulated wind condition data. It classifies the input data and outputs a probability value of 0 or 1, which respectively represents "false" or "true".

[0171] S404: Clustering the simulated wind condition data that meet the authenticity requirements, so as to group the simulated wind condition data with similar wind conditions into one category, and obtain the simulated wind condition data corresponding to different wind conditions.

[0172] In this embodiment, the K-means clustering algorithm is used to cluster the simulated wind condition data that meet the authenticity requirements, so as to cluster the simulated wind condition data with similar wind conditions into one category, and obtain the simulated wind condition data corresponding to different wind conditions.

[0173] Specifically, K data are randomly selected from the simulated wind data that meet the authenticity requirements as the initial cluster centers, and these data are used as the center points of the initial clusters. The distance from each simulated wind data to each cluster center is calculated, and it is assigned to the nearest cluster. For each cluster, the mean of all simulated wind data in the cluster is recalculated as the new cluster center, so that clusters corresponding to various typical wind conditions can be obtained, and each cluster contains the simulated wind data of the typical wind condition.

[0174] In one possible implementation, the generator and discriminator are trained in the following way:

[0175] Generate initial simulated wind condition data of multiple wind turbines using the initial generator to be trained;

[0176] The real wind condition data and the initial simulated wind condition data are input into the initial discriminator to be trained, the loss value of the initial discriminator is calculated according to the discrimination result output by the initial discriminator for indicating the authenticity of the wind condition data, and the learnable parameters in the initial discriminator are updated through the back propagation algorithm, and the loss value of the initial generator is calculated according to the discrimination result output by the initial discriminator for indicating the authenticity of the initial simulated wind condition data, and the learnable parameters in the initial generator are updated through the back propagation algorithm, and the steps of generating initial simulated wind condition data of multiple wind turbines using the initial generator to be trained and subsequent steps are repeated until the loss value of the initial generator is less than the first preset loss value and the loss value of the initial discriminator is greater than the first preset loss value, the training is completed, and the trained generator and discriminator are obtained.

[0177] In a possible implementation, the cascade expansion simulation system of the wind turbine transmission chain further includes a host computer and a second server, the host computer is in communication connection with the second server, and after the inflow and outflow wind model, the first-level operation dynamic simulation model of the wind turbine whole machine, and the second-level operation dynamic simulation model of the transmission chain multi-body dynamics are tested to operate normally, the following steps S501-S502 can be performed:

[0178] S501: deploying the inflow wind model to the host computer, and deploying the first-level operation dynamic simulation model of the wind turbine set and the second-level operation dynamic simulation model of the transmission chain multi-body dynamics to the second server.

[0179] S502: Sending the simulated wind condition data corresponding to different wind conditions to the host computer, so that the host computer inputs the simulated wind condition data into the inflow wind model respectively, and outputs the three-dimensional turbulent wind field corresponding to the simulated wind condition data through the inflow wind model.

[0180] When executing step S102 so that the wind turbine generator set first-level operation dynamic simulation model outputs the standard values ​​of the total aerodynamic torque and the generator electromagnetic torque to the transmission chain multi-body dynamics second-level operation dynamic simulation model based on the input three-dimensional turbulent wind field, so as to drive the transmission chain multi-body dynamics second-level operation dynamic simulation model to operate, the following steps can be specifically performed:

[0181] S1021: transmitting the three-dimensional turbulent wind field corresponding to the simulated wind condition data output by the inflow wind model to the second server through the host computer, so that the second server inputs the three-dimensional turbulent wind field corresponding to the simulated wind condition data into the first-level operation dynamic simulation model of the wind turbine generator set;

[0182] S1022: The first-level operation dynamic simulation model of the wind turbine generator set outputs the standard values ​​of the total aerodynamic torque and the electromagnetic torque of the generator corresponding to the simulated wind condition data to the second-level operation dynamic simulation model of the transmission chain multi-body dynamics based on the three-dimensional turbulent wind field corresponding to the input simulated wind condition data, so as to drive the second-level operation dynamic simulation model of the transmission chain multi-body dynamics to operate.

[0183] In this embodiment, after executing step S103, the following steps S1041-S1043 may also be performed:

[0184] S1041: collecting vibration characteristics and load characteristics of each component in the gearbox corresponding to each simulated wind condition data;

[0185] S1042: training a neural network model of the gearbox using vibration characteristics and load characteristics of each component in the gearbox corresponding to each simulated wind condition data collected, to obtain a trained neural network model of the gearbox;

[0186] S1043: Deploy the gearbox neural network model to the second server, and use the gearbox neural network model to replace the gearbox multi-body dynamics model deployed in the second server.

[0187] In this embodiment, load and vibration signals under different wind conditions are used as training sets to train a deep neural network for time series data prediction.

[0188] In a possible implementation, after obtaining the trained gearbox neural network model, the gearbox neural network model is deployed to the second server and replaces the gearbox multi-body dynamics model deployed in the second server.

[0189] In this embodiment, since the running speed of the gearbox neural network model is greater than the running speed of the gearbox multi-body dynamics model, replacing the gearbox multi-body dynamics model with the gearbox neural network model is beneficial to improving the running speed of the model.

[0190] In a possible implementation, the first-level dynamic simulation model of the wind turbine generator set includes: a pneumatic system node finite element model, a tower finite element model, a pitch system lumped parameter model, a transmission system lumped parameter model, a generator lumped parameter model, a three-phase power grid, a torque controller, a pitch controller, a machine-side converter, and a grid-side converter;

[0191] like Figure 2 As shown in the figure, during the operation of the first-level dynamic simulation model of the wind turbine set, the aerodynamic system finite element model is used to receive the three-dimensional turbulent wind field and the actual value β of the pitch angle sent by the lumped parameter model of the variable pitch system, and send the total aerodynamic torque T to the lumped parameter model of the transmission system. r , send the component of the total aerodynamic moment along the radial direction of the blade to the tower finite element model, and receive the aerodynamic force on the tower top node sent by the tower finite element model, and calculate the forward and backward thrust F of the aerodynamic system on the tower top based on the component of the total aerodynamic moment along the radial direction of the blade and the aerodynamic force on the tower top node t ;

[0192] The tower finite element model is used to receive the three-dimensional turbulent wind field and the total aerodynamic torque component along the radial direction of the blade sent by the aerodynamic system finite element model, and calculate the forward and backward thrust F of the aerodynamic system on the tower top based on the total aerodynamic torque component along the radial direction of the blade and the aerodynamic force on the tower top node. t ;

[0193] The transmission system lumped parameter model is used to receive the generator electromagnetic torque T sent by the generator lumped parameter model. e , and the total aerodynamic torque T sent by the finite element model of the receiving aerodynamic system r , and sends the wind rotor speed ω to the pitch controller r , send the generator rotor angular velocity ω to the torque controller g , send the generator rotor angular velocity ω to the generator lumped parameter model g , send the total aerodynamic torque T to the gearbox multibody dynamics model r ;

[0194] The generator lumped parameter model is used to send the actual value of the generator electromagnetic torque T to the transmission system lumped parameter model e , and the rotor angular velocity ω of the generator sent by the lumped parameter model of the receiving transmission system g , the q-axis current i of the generator rotor sent by the machine-side converter rq ;

[0195] The lumped parameter model of the variable pitch system is used to send the actual value β of the pitch angle to the finite element model of the aerodynamic system and receive the standard value β of the pitch angle sent by the variable pitch controller * ;

[0196] The pitch controller is used to receive the one-dimensional scalar wind speed and the wind rotor speed ω from the lumped parameter model of the transmission system. r , and send the standard value β of the pitch angle to the lumped parameter model of the variable pitch system * ;

[0197] The torque controller is used to receive the rotor angular velocity ω of the generator sent by the lumped parameter model of the transmission system g , and the standard value of the generator electromagnetic torque sent to the machine-side converter Sending the standard value of the generator electromagnetic torque to the generator multibody dynamics model

[0198] The generator-side converter is used to receive the DC bus voltage provided by the grid-side converter and the standard value of the generator electromagnetic torque sent by the torque controller. And send the q-axis current i of the generator rotor to the generator lumped parameter model rq ;

[0199] The grid-side converter is used to provide a DC bus voltage to the machine-side converter.

[0200] In a possible implementation manner, the pneumatic system finite element model is constructed by following the steps S601-S605:

[0201] S601: For each wind rotor blade in the wind turbine generator set, determine the position of each blade node in the wind rotor blade according to a first preset node number and a length of the wind rotor blade.

[0202] In this embodiment, if Figure 4 As shown, a wind turbine generator set usually includes three wind rotor blades. For each wind rotor blade, according to a first preset node number and the length of the wind rotor blade, a first preset node number of blade nodes are evenly distributed on the wind rotor blade, thereby determining the position of each blade node in the wind rotor blade.

[0203] S602: Construct an aerodynamic force expression for a blade node; wherein the aerodynamic force expression for a blade node is used to output the aerodynamic force of each blade node in the wind turbine blade according to the input air density and the wind speed, force area, lift coefficient, drag coefficient, and windward angle at the blade node.

[0204] In this embodiment, the aerodynamic force expression of the blade node is:

[0205]

[0206] In the above expressions, u, v, and w represent the first direction, the second direction, and the third direction perpendicular to each other, respectively; Figure 2 As shown, the first direction u is a direction perpendicular to the plane where the wind rotor blades are located, the plane formed by the second direction v and the third direction w is parallel to the plane where the wind rotor blades are located, and the third direction is a direction perpendicular to the ground and upward.

[0207] ρ a represents air density; l represents blade node l; u l 、v l 、w l Respectively represent the wind speed of blade node l in the first direction, the second direction and the third direction; represents the force area at the blade node l; C L,l and C D,l are the lift coefficient and drag coefficient at the blade node l, respectively; θ l is the windward angle at the blade node l; F u aero,l 、F v aero,l 、F w aero,l are the aerodynamic forces of the blade node l in the first direction, the second direction and the third direction respectively.

[0208] S603: Construct an aerodynamic torque expression; wherein the aerodynamic torque expression is used to output the aerodynamic torque of the blade node according to the input aerodynamic force of the blade node and the distance between the blade node and the root of the wind turbine blade.

[0209] In this embodiment, the global coordinate system (u, v, w) is converted into the local coordinate system (α, β, γ) of the leaf node by the following coordinate conversion formula:

[0210]

[0211] Wherein, ψ∈[0,2π]; N is the blade parameter, N=0 for wind rotor blade 1, N=1 for wind rotor blade 2, and N=2 for wind rotor blade 3.

[0212] The local coordinate system (α, β, γ) is as follows Figure 4 As shown, the α direction is along the axial direction of the wind rotor blade; the β direction is along the radial direction of the wind rotor blade, that is, the direction perpendicular to the plane where the wind rotor blade is located; and the γ direction is perpendicular to the edge of the wind rotor blade.

[0213] The aerodynamic torque expression is:

[0214] dT r,l =F γ aero,l ·r l

[0215] dTr,l is the aerodynamic moment of blade node l; F γ aero,l is the component of the aerodynamic force of blade node l along the γ direction, where the γ direction is perpendicular to the blade; r l is the distance between the leaf node l and the leaf root.

[0216] S604: constructing a total aerodynamic torque expression; wherein the total aerodynamic torque expression is used to accumulate and sum the aerodynamic torques of all blade nodes on all wind rotor blades to obtain the total aerodynamic torque of all wind rotor blades.

[0217] The total aerodynamic torque expression is:

[0218]

[0219] Where n is the total number of leaf nodes, T r is the total aerodynamic torque.

[0220] S605: constructing a blade root bending moment expression; wherein the blade root bending moment expression is used to calculate the blade root bending moment of all wind rotor blades according to the aerodynamic force of each blade node in all wind rotor blades and the distance between each blade node in each wind rotor blade and the blade root of the wind rotor blade; the aerodynamic system node finite element model is composed of the total aerodynamic moment expression and the blade root bending moment expression.

[0221] In this embodiment, the blade root bending moment expression is:

[0222]

[0223] Among them, F β aero,l is the component of the aerodynamic force of blade node l along the β direction, where the β direction is along the radial direction of the wind rotor blade; M root is the blade root bending moment.

[0224] In a possible implementation manner, the tower finite element model is constructed by following the steps S606-S608:

[0225] S606: For a tower in a wind turbine generator set, determine the position of each tower node in the tower according to a second preset number of nodes and a length of the tower.

[0226] In this embodiment, if Figure 4 As shown, according to the second preset node number and the length of the tower, the second preset node number of tower nodes are evenly distributed on the tower, so as to determine the position of each tower node in the tower.

[0227] S607: Constructing an aerodynamic force expression for a tower node; wherein the aerodynamic force expression for a tower node is used to output the aerodynamic force of the tower node for each tower node according to the input air density, the drag coefficient of the tower, and the scalar wind speed and windward area at the tower node.

[0228] In this embodiment, the tower node aerodynamic expression is:

[0229]

[0230] Where j is the tower node j; F external,j is the aerodynamic force at tower node j; ρ a Indicates the air density; is the scalar wind speed at tower node j; C D is the tower resistance coefficient; A j is the windward area at the tower node;

[0231] S608: Construct a tower finite element model based on the mass matrix, damping matrix and stiffness matrix of the tower; the tower finite element model is used to calculate the vibration displacement of each tower node according to the aerodynamic force of each tower node.

[0232] In this embodiment, the tower finite element model is:

[0233]

[0234] Among them, M t , C t and K t are respectively the mass matrix, damping matrix and stiffness matrix of the tower which are preset; F external is a vector containing the aerodynamic forces of all tower nodes in the tower; u t is a vector containing the vibration displacements of all tower nodes in the tower.

[0235] In a possible implementation manner, the generator lumped parameter model is constructed by following the steps S701-S703:

[0236] S701: For a generator stator and a generator rotor in a wind turbine generator set, obtain a d-axis current and a q-axis current of the generator stator and the generator rotor in a dq rotating coordinate system.

[0237] S702: constructing a flux equation of the generator stator in a dq rotating coordinate system; wherein the flux equation of the generator stator is used to calculate the flux of the generator stator based on the self-inductance of the generator stator, the mutual inductance between the generator stator and the generator rotor, and the d-axis current and q-axis current of the generator stator and the generator rotor.

[0238] In this embodiment, the flux equation of the generator stator and the flux equation of the generator rotor are:

[0239] ψ sd =L s i sd +L m i rd

[0240] ψ sq =L s i sq +L m i rq

[0241] ψ rd =L r i rd +L m i sd

[0242] ψ rq =L r i rq +L m i sq

[0243] Among them, L s and L r is the self-inductance of the generator stator and the generator rotor; L m is the mutual inductance between the generator stator and the generator rotor; i sd ,i sq ,i rd ,i rq are the d-axis current and q-axis current of the generator stator and the generator rotor respectively; ψ sd , sq are the flux linkage of the generator stator; ψ rd , rq are the magnetic flux of the generator rotor respectively.

[0244] S703: constructing a lumped parameter model of the generator; wherein the lumped parameter model of the generator is used to calculate the electromagnetic torque of the generator according to the number of pole pairs of the generator and the flux linkage of the stator of the generator.

[0245] In this embodiment, the lumped parameter model of the generator is:

[0246]

[0247] Where p is the number of pole pairs of the generator, T e is the electromagnetic torque of the generator.

[0248] In a possible implementation, the lumped parameter model of the variable pitch system is constructed by the following steps: constructing the lumped parameter model of the variable pitch system; wherein the lumped parameter model of the variable pitch system is used to calculate the actual value of the pitch angle according to the standard value of the input pitch angle.

[0249] In this embodiment, the pitch motor is equivalent to a first-order inertia link, and the lumped parameter model of the pitch system is:

[0250]

[0251] Among them, τ p is the time constant of the pitch actuator; β * (t) is the standard value of the pitch angle; β(t) is the actual value of the pitch angle.

[0252] In one possible implementation, the lumped parameter model of the transmission system is constructed by the following steps: constructing a lumped parameter model of the transmission system; wherein the lumped parameter model of the transmission system is used to calculate the wind wheel rotor speed and the generator rotor speed based on the input wind wheel aerodynamic torque and the generator electromagnetic torque; the gearbox is located in the transmission system of the wind turbine.

[0253] In this embodiment, the lumped parameter model of the transmission system is:

[0254]

[0255] Among them, T r and T e are the total aerodynamic torque of the wind rotor blades and the electromagnetic torque of the generator respectively; ω r and ω g is the wind rotor speed and the generator rotor angular velocity; T shaft is the equivalent intermediate shaft torque; J r and J g is the moment of inertia of the wind rotor and the generator rotor; r and δ g is the angular displacement between the wind rotor side and the generator rotor side, δ p is the gearbox slip rate; N gear is the gearbox speed ratio; A stif and B damp are the equivalent intermediate shaft stiffness coefficient and damping coefficient.

[0256] In a possible implementation manner, the inflow wind model is constructed by following the steps S801-S8010:

[0257] S201: construct an expression for the relationship between turbulence intensity and inflow wind; wherein the expression for the relationship between turbulence intensity and inflow wind is used to represent the correlation between the average wind speed of inflow wind at the hub of the wind turbine, the standard deviation of the inflow wind speed, and turbulence intensity.

[0258] In this embodiment, the expression for the relationship between turbulence intensity and inflow wind is:

[0259]

[0260] In this formula, I represents the turbulence intensity; U Ref It represents the average wind speed of the inflow wind at the hub of the wind turbine; σ represents the standard deviation of the inflow wind speed, which reflects the degree of random fluctuation of the wind speed.

[0261] S802: Based on the height of the hub, determine the turbulence integral scale lengths in three mutually perpendicular directions in the three-dimensional turbulent wind field; wherein the three mutually perpendicular directions are a first direction, a second direction, and a third direction, the first direction is a direction perpendicular to the plane where the wind rotor blades are located, the plane formed by the second direction and the third direction is parallel to the plane where the wind rotor blades are located, and the third direction is a direction perpendicular to the ground and upward.

[0262] In this embodiment, the turbulence integral scale lengths in three mutually perpendicular directions in the three-dimensional turbulent wind field are determined according to the following formula:

[0263] L u =0.7·H

[0264] L v =0.5·L u

[0265] L w =0.35·L v

[0266] In this formula, L u , L v , L w are the turbulence integral scale lengths in the first direction (u direction), the second direction (v direction), and the third direction (w direction); H is the height of the hub.

[0267] S803: Calculate the turbulence power spectrum density in three directions based on the Kaimal turbulence spectrum, the average wind speed, the standard deviation of the inflow wind speed in three directions, the turbulence integral scale length in three directions, and the frequency; wherein the frequency range is determined by the Shannon sampling theorem.

[0268] In this embodiment, the turbulence power spectrum density in three directions is calculated by the following formula:

[0269]

[0270] Where f is the frequency, i.e., the independent variable of the frequency domain wind speed in the three directions (u, v, w) within the total simulation time T. Its range can be determined by the following Shannon sampling theorem:

[0271]

[0272] Assume that there are N x time steps, then we can deduce that T = N x ·Δt, then the frequency increment Δf can be expressed as Δf = 1 / T. It can be deduced that in the total simulation time T, there are N x / 2 frequency points.

[0273] S u (f),S v (f),S w (f) are the turbulence power spectral density in the first direction (u direction), the second direction (v direction), and the third direction (w direction) at frequency f; σ u , σ v , σ w They are the standard deviations along the first direction (u direction), the second direction (v direction), and the third direction (w direction), respectively.

[0274] S804: Determine a three-dimensional grid of the three-dimensional turbulent wind field according to the swept area of ​​the wind rotor blades.

[0275] In this embodiment, a three-dimensional grid of a three-dimensional turbulent wind field is defined according to the swept area of ​​the wind rotor blades. Figure 5 As shown, the three-dimensional grid of the three-dimensional turbulent wind field is composed of N x parallel two-dimensional wind grids ( Figure 5 Only three two-dimensional wind grids are shown in the figure), and the size of each two-dimensional wind grid is N y ×N z ( Figure 5 A 3×3 2D wind grid is shown in FIG. 1 ). Where N y and N z are the number of grids in the first direction (v direction) and the second direction (w direction) of the wind field. That is, the shape of the three-dimensional grid of the three-dimensional turbulent wind field is N x ×N y ×N z .

[0276] S805: Calculate the wind speed components in the three directions in the frequency domain according to the turbulence power spectrum density and the frequency increment in the three directions.

[0277] In this embodiment, in order to ensure the randomness of wind speed, a random phase is generated at each grid point of the three-dimensional grid of the three-dimensional turbulent wind field. It is a random number in the interval [0, 2π]. Assume that the frequency resolution is Δf. For each frequency f and each direction (i.e., u, v, w directions), use the following formula to generate the wind speed component in the frequency domain:

[0278]

[0279] in, is the wind speed component in the frequency domain in the u direction at frequency f; j, k represent the grid points located in the jth row and kth column in the two-dimensional wind grid. is the wind speed component in the frequency domain in the direction v at frequency f; It is the wind speed component in the frequency domain at frequency f in the direction w.

[0280] S806: Perform Fourier transform on the wind speed component in the frequency domain at each grid point in the three-dimensional grid to obtain the wind speed component in the time domain at each grid point in the three-dimensional grid.

[0281] In this embodiment, the wind speed component in the frequency domain at each grid point is calculated by the following formula: Perform Fourier transform to obtain the wind speed component in the time domain at each grid point:

[0282]

[0283] Among them, m represents the mth time step, It represents the wind speed component in the time domain in the u direction for the grid point in the jth row and kth column on the two-dimensional wind grid corresponding to the mth time step; It represents the wind speed component in the time domain in the v direction for the grid point in the jth row and kth column on the two-dimensional wind grid corresponding to the mth time step; It represents the wind speed component in the time domain in the w direction for the grid point in the j-th row and k-th column on the two-dimensional wind grid corresponding to the m-th time step.

[0284] S807: Calculate the coherence coefficients of the two points based on the turbulence integral scale lengths in the three directions and the distances between the two points in the three-dimensional grid in the second direction and the third direction.

[0285] In this embodiment, the distances between two points a and b on the grid in the v direction and the w direction are defined as Δy ab , Δz ab The spatial coherence model can be written as:

[0286]

[0287] Among them, ρ ab Represents the coherence coefficient of two points a and b in a three-dimensional grid.

[0288] S808: Construct a covariance matrix and perform Cholesky decomposition on the covariance matrix.

[0289] In this embodiment, the covariance matrix is ​​assumed to be C, which can be expressed as:

[0290]

[0291] In order to introduce spatial correlation into the initial uncorrelated wind speed field, the covariance matrix C is decomposed by Cholesky, that is, C = LL T .

[0292] S809: Constructing vectors of wind speeds without introducing coherence at all grid points.

[0293] In this embodiment, when the time step is equal to t, Z(t) is the vector composed of the wind speeds without introducing coherence at all grid points in the current time step:

[0294]

[0295] S8010: Use the Cholesky decomposition matrix to linearly transform the vectors composed of wind speeds without introducing coherence at all grid points to obtain the model of the inflow wind model.

[0296] In this embodiment, in order to introduce the spatial coherence of the three-dimensional turbulent wind field, the Cholesky decomposition matrix L is used to perform a linear transformation on the wind speed vector Z without introducing the spatial coherence, and the model of the inflow wind model is obtained as follows:

[0297] V(t)=Z(t)L T

[0298] At this time, each element in the vector V is the wind speed vector corresponding to each grid point at the current sampling moment. According to the above method, the wind speed of each grid point at the current sampling moment can be obtained.

[0299] In a possible implementation, Figure 6 As shown, when the one-dimensional scalar wind speed V eff Greater than rated wind speed V rated When the torque controller calculates the generator rated power P rated and the generator rotor speed P rated The ratio of the generator electromagnetic torque is obtained. Right now:

[0300]

[0301] The machine-side converter calculates the standard value of the generator electromagnetic torque based on the torque controller Calculate the q-axis component i of the rotor current rq; The q-axis component i of the rotor current calculated by the generator lumped parameter model is rq , calculate the actual value of the generator electromagnetic torque T e ;

[0302] When the one-dimensional scalar wind speed V eff Greater than rated wind speed V rated When the pitch controller uses the PI control strategy, the received wind rotor speed ω r , calculate the product of the wind wheel rotor speed and the gearbox speed ratio N g , and calculate the product N g and the rated speed of the generator rotor ω rated When the difference is not equal to 0, the pitch controller receives the wind turbine rotor speed ω r The standard value of the pitch angle β is calculated based on the rated speed of the generator rotor. * ; The standard value β of the pitch angle calculated by the pitch controller according to the lumped parameter model of the pitch system * , calculate the actual value of the pitch angle β; the aerodynamic system finite element model calculates the actual value of the pitch angle β based on the variable pitch system lumped parameter model, and calculates the wind rotor aerodynamic torque T r ; The wind wheel aerodynamic torque T calculated by the lumped parameter model of the transmission system based on the finite element model of the aerodynamic system r , calculate the wind wheel rotor speed ω r ; The pitch controller continues to receive the wind rotor speed ω r , calculate the wind wheel rotor speed ω r The product of the gearbox speed ratio and the product N is calculated. g and the rated speed of the generator rotor ω rated When the difference is not equal to 0, the pitch controller continues to calculate the standard value of the pitch angle and subsequent steps according to the received wind rotor speed and the rated speed of the generator rotor, and stops when the difference is equal to 0 to obtain the final wind rotor speed;

[0303] When the one-dimensional scalar wind speed V eff Less than or equal to rated wind speed V rated When the torque controller calculates the standard value of the generator electromagnetic torque according to the OTC torque control strategy The machine-side converter calculates the standard value of the generator electromagnetic torque based on the torque controller Calculate the q-axis component i of the rotor current rq ; The q-axis component i of the rotor current calculated by the generator lumped parameter model is rq , calculate the actual value of the generator electromagnetic torque T e ;

[0304] When the one-dimensional scalar wind speed V eff Less than or equal to rated wind speed V rated When , the standard value β of the pitch angle output by the pitch controller is equal to 0.

[0305] In this embodiment, the OTC torque control strategy is:

[0306]

[0307] In the above OTC torque control strategy, ω cut-in is the cut-in speed, corresponding to the speed when the wind speed is cut in; ω 1 is the transition speed corresponding to the maximum power tracking stage; ω 2 is the transition speed corresponding to the rated power maintenance stage; ω rated is the rated speed of the wind wheel rotor; k opt is the coefficient of the maximum power tracking stage.

[0308] It is worth noting that the rated speed of the generator rotor is different from the generator rotor speed. The rated speed of the generator rotor is a specific parameter designed when the generator leaves the factory and is a fixed value; the generator rotor speed is the real-time speed of the generator.

[0309] In the embodiments provided in the present application, it should be understood that the embodiments described above are merely illustrative. For example, the division of the system is merely a logical function division, and there may be other division methods in actual implementation. For example, multiple systems or components may be combined or integrated into another system, or some features may be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed may be an indirect coupling or communication connection through some communication interface, device or unit, which may be electrical, mechanical or other forms.

[0310] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0311] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0312] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a non-volatile computer-readable storage medium that is executable by a processor. Based on this understanding, the technical solution of the present application can essentially be embodied in the form of a software product, or in other words, the part that contributes to the prior art or the part of the technical solution. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0313] Finally, it should be noted that the above-described embodiments are only specific implementation methods of the present application, which are used to illustrate the technical solutions of the present application, rather than to limit them. The protection scope of the present application is not limited thereto. Although the present application is described in detail with reference to the above-described embodiments, ordinary technicians in the field should understand that any technician familiar with the technical field can still modify the technical solutions recorded in the above-described embodiments within the technical scope disclosed in the present application, or can easily think of changes, or make equivalent replacements for some of the technical features therein; and these modifications, changes or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A cascade expansion simulation method for a wind turbine transmission chain, characterized in that: The method comprises: Constructing a first-level dynamic operation simulation model of the wind turbine as a whole unit, and constructing a second-level dynamic operation simulation model of the transmission chain multi-body dynamics; wherein the second-level dynamic operation simulation model of the transmission chain multi-body dynamics includes a sequentially linked gearbox multi-body dynamics model, a coupling model, and a generator multi-body dynamics model; The first-level operation dynamic simulation model of the wind turbine set and the second-level operation dynamic simulation model of the transmission chain multi-body dynamics are jointly operated, so that the first-level operation dynamic simulation model of the wind turbine set outputs standard values ​​of the total aerodynamic torque and the electromagnetic torque of the generator to the second-level operation dynamic simulation model of the transmission chain multi-body dynamics based on the input three-dimensional turbulent wind field, so as to drive the second-level operation dynamic simulation model of the transmission chain multi-body dynamics to operate; During the operation of the transmission chain multi-body dynamics secondary operation dynamic simulation model, the gearbox multi-body dynamics model outputs the vibration characteristics and load characteristics of each component in the gearbox based on the input total aerodynamic torque and the generator electromagnetic torque obtained from the generator multi-body dynamics model through the coupling model; and the generator multi-body dynamics model outputs the actual value of the generator electromagnetic torque based on the input standard value of the generator electromagnetic torque and the rotor angular velocity of the generator obtained from the gearbox multi-body dynamics model through the coupling model.

2. The method according to claim 1, characterized in that: The construction process of the gearbox multi-body dynamics model includes: Constructing a simulation structure of the multi-body dynamics model of the gearbox; wherein the simulation structure of the multi-body dynamics model of the gearbox includes a gearbox housing, a primary planetary gear train, a secondary planetary gear train, a tertiary parallel gear train, an intermediate shaft, a high-speed shaft and corresponding bearings; Based on a preset total transmission ratio, determining the transmission ratio of each gear in the primary planetary gear train, the secondary planetary gear train and the tertiary parallel gear train, so that the transmission ratio of each gear in the gearbox satisfies the total transmission ratio; Selecting corresponding materials for various components in the gearbox multi-body dynamics model; Verify the gear strength, shaft strength and bearing life in the gearbox multi-body dynamics model to determine whether the simulated gearbox multi-body dynamics model meets the requirements; The simulated gearbox multi-body dynamics model that meets the requirements is determined as the constructed gearbox multi-body dynamics model.

3. The method according to claim 2, characterized in that: The construction process of the generator multi-body dynamics model includes: Constructing a simulation structure of the generator multi-body dynamics model; wherein the simulation structure of the generator multi-body dynamics model includes a stator core, a rotor core, a stator winding, a rotor winding, and a main shaft; Select corresponding materials for the stator core, the rotor core, the stator winding, the rotor winding, and the main shaft respectively; Performing torsional strength check, bending strength check and combined stress check on the main shaft to determine whether the material selected for the generator multi-body dynamics model can meet the strength check requirements; When the material selected for the generator multi-body dynamics model can meet the requirements of strength verification, constructing the coupling model according to the diameter of the main shaft; Wherein, constructing the coupling model according to the diameter of the main shaft includes: Determining the parameters of the coupling model according to the diameter of the main shaft and the diameter of the high-speed shaft to construct a simulation structure of the coupling model; Selecting a corresponding material for the coupling model; Performing torsional strength check, bending strength check, and combined stress check on the coupling model to determine whether the material selected for the coupling model meets the strength check requirements; When the material selected for the coupling model meets the requirements of strength verification, the coupling model is used to connect the main shaft with the high-speed shaft in the gearbox multi-body dynamics model.

4. The method according to claim 2, characterized in that: The first-stage planetary gear train includes a low-speed shaft, a sun gear, a plurality of planetary gears, and an inner gear ring; the second-stage planetary gear train includes a second-stage planet carrier, a sun gear, a plurality of planetary gears, and an inner gear ring; the third-stage parallel gear train includes a third-stage large gear and a third-stage small gear; The inner gear ring in the first-stage planetary gear train and the inner gear ring in the second-stage planetary gear train are hinged to the gearbox housing, and the gearbox housing is hinged to the low-speed shaft, the second-stage planetary carrier, the intermediate shaft, and the high-speed shaft respectively through spring damping force elements; In the primary planetary gear train, a plurality of planetary gears are hinged to the low-speed shaft via a spring damping force element, a plurality of planetary gears are also respectively connected to the sun gear and the inner gear ring via a spring damping force element, and the sun gear is also hinged to the secondary planet carrier; In the secondary planetary gear system, the secondary planet carrier is hinged to the multiple planetary gears through a spring damping force element, and the multiple planetary gears are also respectively connected to the sun gear and the inner gear ring through a spring damping force element; In the three-stage parallel gear train, the three-stage large gear is connected to the three-stage small gear through a spring damping force element; the intermediate shaft is respectively articulated with the three-stage small gear and the sun gear in the two-stage planetary gear train; the high-speed shaft is also articulated with the three-stage small gear.

5. The method according to claim 2, characterized in that: The checking of the gear strength, shaft strength and bearing life in the gearbox multi-body dynamics model to determine whether the simulated gearbox multi-body dynamics model meets the requirements includes: For each gear in the multi-body dynamics model of the gearbox, the tooth root bending strength and the tooth surface contact strength of the gear are calculated, and when the tooth root bending strength of the gear is less than the preset allowable bending strength, and the tooth surface contact strength is less than the preset allowable contact strength, it is determined that the gear meets the requirements; For each shaft in the multi-body dynamics model of the gearbox, the shear strength, bending strength and combined stress of the shaft are calculated. When the shear strength of the shaft is greater than the preset allowable shear stress, the bending strength is greater than the preset bending strength, and the combined stress is greater than the preset allowable combined stress, it is determined that the shaft meets the requirements; For the bearing in the multi-body dynamics model of the gearbox, the rated dynamic load and equivalent load of the bearing are calculated, and the bearing life of the bearing is determined according to the rated dynamic load and the equivalent load, and when the bearing life meets the preset bearing duration, it is determined that the bearing meets the requirements; When each gear, shaft and bearing in the gearbox multi-body dynamics model meets the requirements, it is determined that the gearbox multi-body dynamics model meets the requirements.

6. The method according to claim 1, characterized in that: The method is applied to a cascade expansion simulation system of a wind turbine transmission chain; the cascade expansion simulation system of a wind turbine transmission chain comprises a first server, a generator, and a discriminator; the three-dimensional turbulent wind field is generated by a simulated inflow wind model; After constructing a first-level dynamic simulation model of the wind turbine set and a second-level dynamic simulation model of the transmission chain multi-body dynamics, the method further includes: The simulated inflow wind model, the first-level operation dynamic simulation model of the wind turbine set and the second-level operation dynamic simulation model of the transmission chain multi-body dynamics are deployed in a first server, and respective computing resources are allocated to the inflow wind model, the first-level operation dynamic simulation model of the wind turbine set and the second-level operation dynamic simulation model of the transmission chain multi-body dynamics in the first server, so that the inflow wind model, the first-level operation dynamic simulation model of the wind turbine set and the second-level operation dynamic simulation model of the transmission chain multi-body dynamics are respectively operated using the computing resources allocated to them, and during the operation of the inflow wind model, the first-level operation dynamic simulation model of the wind turbine set and the second-level operation dynamic simulation model of the transmission chain multi-body dynamics, whether the inflow wind model, the first-level operation dynamic simulation model of the wind turbine set and the second-level operation dynamic simulation model of the transmission chain multi-body dynamics can be tested; After testing that the inflow wind model, the first-level dynamic operation simulation model of the wind turbine set and the second-level dynamic operation simulation model of the transmission chain multi-body dynamics can operate normally, using the trained generator to generate a plurality of simulated wind condition data of the wind turbine set; Using the trained discriminator to judge the authenticity of each of the simulated wind condition data generated by the generator, remove the simulated wind condition data that does not meet the authenticity requirement, and retain the simulated wind condition data that meets the authenticity requirement; The simulated wind condition data that meet the authenticity requirements are clustered to group the simulated wind condition data with similar wind conditions into one category, thereby obtaining the simulated wind condition data corresponding to different wind conditions.

7. The method according to claim 6, characterized in that: The cascade expansion simulation system for the wind turbine transmission chain also includes a host computer and a second server, and the method also includes: Deploy the inflow wind model to the host computer, and deploy the first-level dynamic operation simulation model of the wind turbine set and the second-level dynamic operation simulation model of the transmission chain multi-body dynamics to the second server; Sending the simulated wind condition data corresponding to different wind conditions to the host computer, so that the host computer inputs the simulated wind condition data into the inflow wind model respectively, and outputs the three-dimensional turbulent wind field corresponding to the simulated wind condition data through the inflow wind model; The method is to enable the wind turbine set first-level operation dynamic simulation model to output the standard values ​​of the total aerodynamic torque and the electromagnetic torque of the generator to the transmission chain multi-body dynamics second-level operation dynamic simulation model based on the input three-dimensional turbulent wind field, so as to drive the transmission chain multi-body dynamics second-level operation dynamic simulation model to operate, including: The three-dimensional turbulent wind field corresponding to the simulated wind condition data output by the inflow wind model is transmitted to the second server through the host computer, so that the second server inputs the three-dimensional turbulent wind field corresponding to the simulated wind condition data into the first-level operation dynamic simulation model of the wind turbine set; The wind turbine set first-level operation dynamic simulation model outputs the standard values ​​of the total aerodynamic torque and the electromagnetic torque of the generator corresponding to the simulated wind condition data to the transmission chain multi-body dynamics second-level operation dynamic simulation model based on the three-dimensional turbulent wind field corresponding to the input simulated wind condition data, so as to drive the transmission chain multi-body dynamics second-level operation dynamic simulation model to operate; The method further comprises: Collecting vibration characteristics and load characteristics of each component in the gearbox corresponding to each simulated wind condition data; Using the vibration characteristics and load characteristics of each component in the gearbox corresponding to each of the collected simulated wind condition data to train a neural network model of the gearbox, to obtain a trained neural network model of the gearbox; The gearbox neural network model is deployed to the second server, and the gearbox multi-body dynamics model deployed in the second server is replaced by the gearbox neural network model.

8. The method according to claim 1, characterized in that: The first-level dynamic simulation model of the wind turbine generator set includes: a pneumatic system finite element model, a tower finite element model, a pitch system lumped parameter model, a transmission system lumped parameter model, a generator lumped parameter model, a three-phase power grid, a torque controller, a pitch controller, a machine-side converter, and a grid-side converter; During the operation of the first-level dynamic simulation model of the wind turbine set, the aerodynamic system finite element model is used to receive the three-dimensional turbulent wind field, and receive the actual value of the pitch angle sent by the lumped parameter model of the variable pitch system, and send the total aerodynamic torque to the lumped parameter model of the transmission system, send the component of the total aerodynamic torque along the radial direction of the blade to the tower finite element model, and receive the aerodynamic force on the tower top node sent by the tower finite element model, and calculate the forward and backward thrust of the aerodynamic system on the tower top according to the component of the total aerodynamic torque along the radial direction of the blade and the aerodynamic force on the tower top node; The tower finite element model is used to receive the three-dimensional turbulent wind field and the component of the total aerodynamic moment along the radial direction of the blade sent by the aerodynamic system finite element model, and calculate the forward and backward thrust of the aerodynamic system on the tower top according to the component of the total aerodynamic moment along the radial direction of the blade and the aerodynamic force received by the tower top node; The transmission system lumped parameter model is used to receive the generator electromagnetic torque sent by the generator lumped parameter model, receive the total aerodynamic torque sent by the aerodynamic system finite element model, and send the wind wheel rotor speed to the pitch controller, send the generator rotor angular velocity to the torque controller, send the generator rotor angular velocity to the generator lumped parameter model, and send the total aerodynamic torque to the gearbox multi-body dynamics model; The generator lumped parameter model is used to send the actual value of the electromagnetic torque of the generator to the transmission system lumped parameter model, and receive the rotor angular velocity of the generator sent by the transmission system lumped parameter model and the q-axis current of the generator rotor sent by the machine-side converter; The pitch system lumped parameter model is used to send the actual value of the pitch angle to the aerodynamic system finite element model, and receive the standard value of the pitch angle sent by the pitch controller; The pitch controller is used to receive the one-dimensional scalar wind speed, receive the wind wheel rotor speed from the transmission system lumped parameter model, and send the standard value of the pitch angle to the pitch system lumped parameter model; The torque controller is used to receive the rotor angular velocity of the generator sent by the lumped parameter model of the transmission system, and to send the standard value of the electromagnetic torque of the generator to the machine-side converter and to send the standard value of the electromagnetic torque of the generator to the multi-body dynamics model of the generator; The machine-side converter is used to receive the DC bus voltage provided by the grid-side converter, receive the standard value of the generator electromagnetic torque sent by the torque controller, and send the q-axis current of the generator rotor to the generator lumped parameter model; The grid-side converter is used to provide a DC bus voltage to the generator-side converter.

9. The method according to claim 8, characterized in that: The pneumatic system finite element model is constructed by the following method: For each wind rotor blade in the wind turbine generator set, determine the position of each blade node in the wind rotor blade according to the first preset node number and the length of the wind rotor blade; Constructing an aerodynamic force expression for a blade node; wherein the aerodynamic force expression for a blade node is used to output the aerodynamic force of the blade node for each blade node in the wind rotor blade according to the input air density and the wind speed, force area, lift coefficient, drag coefficient, and windward angle at the blade node; Constructing an aerodynamic torque expression; wherein the aerodynamic torque expression is used to output the aerodynamic torque of the blade node according to the input aerodynamic force of the blade node and the distance between the blade node and the blade root of the wind rotor blade; Constructing a total aerodynamic torque expression; wherein the total aerodynamic torque expression is used to accumulate and sum the aerodynamic torques of all blade nodes on all the wind rotor blades to obtain the total aerodynamic torque of all the wind rotor blades; Constructing a blade root bending moment expression; wherein the blade root bending moment expression is used to calculate the blade root bending moment of all the wind rotor blades according to the aerodynamic force of each blade node in all the wind rotor blades and the distance between each blade node in each of the wind rotor blades and the blade root of the wind rotor blade; the aerodynamic system node finite element model is composed of the total aerodynamic moment expression and the blade root bending moment expression; The tower finite element model is constructed by the following method: For the tower in the wind turbine generator set, determining the position of each tower node in the tower according to the second preset node number and the length of the tower; Constructing an aerodynamic force expression for a tower node; wherein the aerodynamic force expression for a tower node is used to output the aerodynamic force of the tower node for each tower node according to the input air density, the drag coefficient of the tower, and the scalar wind speed and the windward area at the tower node; Based on the mass matrix, damping matrix and stiffness matrix of the tower, a finite element model of the tower is constructed; the finite element model of the tower is used to calculate the vibration displacement of each tower node according to the aerodynamic force of each tower node; The generator lumped parameter model is constructed by the following method: For a generator stator and a generator rotor in the wind turbine generator set, obtaining a d-axis current and a q-axis current of the generator stator and the generator rotor in a dq rotating coordinate system; In the dq rotating coordinate system, a flux equation of the generator stator is constructed; wherein the flux equation of the generator stator is used to calculate the flux of the generator stator according to the self-inductance of the generator stator, the mutual inductance between the generator stator and the generator rotor, and the d-axis current and q-axis current of the generator stator and the generator rotor; Constructing the lumped parameter model of the generator; wherein the lumped parameter model of the generator is used to calculate the electromagnetic torque of the generator according to the pole pair number of the generator and the flux linkage of the stator of the generator; The variable pitch system lumped parameter model is used to calculate the actual value of the pitch angle according to the input standard value of the pitch angle; The transmission system lumped parameter model is used to calculate the wind wheel rotor speed and the generator rotor speed according to the input wind wheel aerodynamic torque and generator electromagnetic torque.

10. The method according to claim 8, characterized in that: When the one-dimensional scalar wind speed is greater than the rated wind speed, the torque controller calculates the ratio of the rated power of the generator to the rotor speed of the generator to obtain the standard value of the electromagnetic torque of the generator; the machine-side converter calculates the q-axis component of the rotor current according to the standard value of the electromagnetic torque of the generator calculated by the torque controller; the generator lumped parameter model calculates the actual value of the electromagnetic torque of the generator according to the q-axis component of the rotor current calculated by the machine-side converter; When the one-dimensional scalar wind speed is greater than the rated wind speed, the pitch controller uses the PI control strategy to calculate the product of the wind rotor speed and the gearbox speed ratio according to the received wind rotor speed, and calculates the difference between the product and the rated speed of the generator rotor. When the difference is not equal to 0, the pitch controller calculates the standard value of the pitch angle according to the received wind rotor speed and the rated speed of the generator rotor; the pitch system lumped parameter model calculates the actual value of the pitch angle according to the standard value of the pitch angle calculated by the pitch controller; the aerodynamic system finite element model calculates the actual value of the pitch angle according to the standard value of the pitch angle calculated by the pitch system lumped parameter model The actual value of the pitch angle is used to calculate the aerodynamic torque of the wind wheel; the lumped parameter model of the transmission system calculates the aerodynamic torque of the wind wheel calculated by the finite element model of the aerodynamic system, and calculates the speed of the wind wheel rotor; the pitch controller continues to calculate the product of the wind wheel rotor speed and the gear ratio of the gear box according to the received wind wheel rotor speed, and calculates the difference between the product and the rated speed of the generator rotor. When the difference is not equal to 0, the pitch controller continues to calculate the standard value of the pitch angle and subsequent steps according to the received wind wheel rotor speed and the rated speed of the generator rotor, and stops when the difference is equal to 0 to obtain the final wind wheel rotor speed; When the one-dimensional scalar wind speed is less than or equal to the rated wind speed, the torque controller calculates the standard value of the electromagnetic torque of the generator according to the OTC torque control strategy; the machine-side converter calculates the q-axis component of the rotor current according to the standard value of the electromagnetic torque of the generator calculated by the torque controller; the generator lumped parameter model calculates the actual value of the electromagnetic torque of the generator according to the q-axis component of the rotor current calculated by the machine-side converter; When the one-dimensional scalar wind speed is less than or equal to the rated wind speed, the standard value of the pitch angle output by the pitch controller is equal to 0.

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