A wind turbine transmission chain test platform electromechanical coupling loading method and system

Abstract

The present application belongs to the field of wind power generation ground test technology, and provides a wind turbine transmission chain test platform electromechanical coupling loading method and system, real-time wind speed and power grid frequency are obtained; dynamic nonlinear aerodynamic load, gravity load and inertia load are calculated according to the real-time wind speed, and are converted through coordinate transformation to form a basic load component; the required electromagnetic torque instruction of the generator is calculated through comprehensive inertia control according to the real-time power grid frequency; based on the physical mechanism of the reverse torque of the generator leading to the tower tube pitching, the pitching angle acceleration of the top of the tower tube is calculated, and the additional inertia bending moment generated at the main shaft due to the pitching motion is calculated; the driving control of the load motor system is carried out according to the electromagnetic torque instruction to simulate the electromagnetic torque impact, the basic load component and the additional inertia bending moment are superimposed, the control of the six-degree-of-freedom loading device is carried out to simulate the structural lateral vibration bending moment, and synchronous loading is realized. The present application greatly improves the authenticity of the test.

Description

Technical Field

[0001] This invention belongs to the field of wind power generation ground testing technology, specifically relating to an electromechanical coupling loading method and system for a wind turbine transmission chain test platform. Background Technology

[0002] The statements in this section are merely background information related to the present invention and do not necessarily constitute prior art.

[0003] The drivetrain of a wind turbine generator set (including the main shaft, gearbox, couplings, etc.) is the core link in energy conversion, and its reliability directly affects the operational efficiency of a wind farm. Currently, ground tests of wind turbine generator drivetrains mainly focus on simulating aerodynamic loads at the rotor end, including using a six-degree-of-freedom loading device to simulate wind shear, torque fluctuations caused by turbulent wind, and non-torque loads (such as bending moment and shear force).

[0004] However, with the construction of a new power system based primarily on new energy sources, wind turbines are no longer simple passive grid-connected devices, but need to undertake frequency support functions such as primary frequency regulation and inertia response. Existing technologies have the following significant drawbacks:

[0005] First, there is a lack of feedback simulation of grid frequency dynamics. Existing test benches typically simplify the grid-side load as a constant or drag torque that varies according to the power curve. In reality, when the grid frequency is disturbed (such as a sudden frequency drop), the wind turbine controller rapidly increases the generator's electromagnetic torque to release the rotor's kinetic energy (inertia response). This millisecond-level torque mutation will generate a severe bidirectional squeezing impact on the gearbox tooth surface, and existing test benches that only simulate aerodynamic loads cannot reproduce this condition.

[0006] Second, the coupling effect between electromechanical and structural aspects is ignored. In existing tests, the six-degree-of-freedom loading (simulating wind) and the load motor loading (simulating electricity) are decoupled. In reality, when the generator generates a huge sudden change in reaction torque to support the grid frequency, this torque acts on the top of the tower, causing the tower to experience instantaneous pitching or deformation. This structural vibration, in turn, generates an additional inertial bending moment on the main shaft of the drive train. Existing test methods fail to convert grid impact into structural deformation, resulting in loading boundary conditions that are simpler than actual operating conditions, making it difficult to detect potential bearing failures under such complex conditions. Summary of the Invention

[0007] To address the aforementioned problems, this invention proposes an electromechanical coupling loading method and system for a wind turbine drivetrain test platform. This invention considers the grid frequency support characteristics and electromechanical-structural coupling effects to load the drivetrain, providing an effective means for drivetrain dynamic response analysis and wind turbine life assessment.

[0008] According to some embodiments, the present invention adopts the following technical solution:

[0009] An electromechanical coupling loading method for a wind turbine drivetrain test platform includes the following steps:

[0010] Obtain real-time wind speed and power grid frequency;

[0011] The dynamic nonlinear aerodynamic load, gravity load, and inertial load are calculated based on real-time wind speed and transformed through coordinate transformation to form the basic load components.

[0012] Based on the real-time power grid frequency, comprehensive inertia control is performed to calculate the electromagnetic torque command required by the generator.

[0013] Based on the physical mechanism of tower pitch caused by generator reverse torque, the pitch angular acceleration at the top of the tower is calculated, and the additional inertial bending moment generated at the main axis due to pitch motion is calculated.

[0014] According to the electromagnetic torque command, the load motor system is driven and controlled to simulate electromagnetic torque impact. The basic load component and additional inertial bending moment are superimposed to control the six-degree-of-freedom loading device to simulate the structural side vibration bending moment and achieve synchronous loading.

[0015] As an alternative implementation method, the process of calculating dynamic nonlinear aerodynamic loads, gravity loads, and inertial loads based on real-time wind speed and transforming them into basic load components through coordinate transformation includes: obtaining the magnitudes of aerodynamic loads, gravity loads, and inertial loads based on real-time wind speed using blade element-momentum theory; decomposing the obtained loads into axial torque loads and five-degree-of-freedom non-torque loads in other directions; and then transforming them into the hub coordinate system.

[0016] As an alternative implementation, the wind turbine transmission chain test platform simulates torque load through a load motor system, simulates non-torque load of the unit through hydraulic cylinder output, and simulates the remaining five-degree-of-freedom non-torque load symmetrically through the hydraulic cylinder device in the wind turbine transmission chain test platform.

[0017] As an alternative implementation method, the process of performing integrated inertia control based on the real-time grid frequency includes: using virtual inertia control to change the active power output of the wind turbine according to the frequency change rate.

[0018] By using droop control, the active power output of the wind turbine is changed according to the frequency deviation;

[0019] Combining virtual inertia control and droop control forms a comprehensive inertia control system.

[0020] As an alternative implementation, the process of calculating the electromagnetic torque command required by the generator includes: obtaining the frequency-regulating power through integrated inertia control, and superimposing it with the power value obtained from maximum power point tracking control as the power reference value of the wind turbine. The frequency-regulating power of integrated inertia control is:

[0021] ;

[0022] in, Frequency modulation power for integrated inertia control; This is the virtual inertia coefficient, used to simulate inertia response; This is the droop control factor, used to simulate primary frequency modulation. For power grid frequency deviation, Let t be the rate of change of the power grid frequency, and t be time.

[0023] Divide the obtained frequency-modulated power by the real-time speed to obtain the additional torque increment required at this point. :

[0024] ;

[0025] The rotor angular velocity is the total electromagnetic torque that ultimately acts on the transmission chain. T e for:

[0026] ;

[0027] in, T opt This refers to the base torque under maximum power point tracking control of the wind turbine.

[0028] As an alternative implementation, based on the physical mechanism of tower pitch caused by generator reverse torque, the process of calculating the pitch angular acceleration at the top of the tower includes: using electromagnetic torque T e mutation amount T f As the excitation source causing the pitch vibration of the tower;

[0029] Calculations based on the torque-tower pitch dynamics model yielded the following:

[0030] ;

[0031] in, , , , These are the equivalent moment of inertia coefficient, damping coefficient, stiffness coefficient, and pitch acceleration of the wind turbine tower, respectively.

[0032] As an alternative implementation, the process of calculating the additional inertial bending moment generated at the principal axis due to pitch motion includes: the generated additional inertial pitch bending moment at the principal bearing. M add for:

[0033] ;

[0034] in, J eq This is the equivalent moment of inertia of the transmission chain in the tower pitch direction.

[0035] As an alternative implementation, the process of controlling the six-degree-of-freedom loading device by superimposing the basic load components and the additional inertial bending moment includes: the commands that the six-degree-of-freedom loading device needs to execute in the pitch direction are:

[0036] ;

[0037] in, M y The pitching moment of the foundation caused by aerodynamic factors. M add This is the calculated additional inertial bending moment caused by the pitching vibration of the tower.

[0038] An electromechanical coupling loading system for a wind turbine drivetrain test platform includes:

[0039] The data acquisition module is configured to acquire real-time wind speed and power grid frequency;

[0040] The basic aerodynamic load calculation module is configured to calculate dynamic nonlinear aerodynamic loads, gravity loads, and inertial loads based on real-time wind speed, and to form basic load components through coordinate transformation.

[0041] The frequency-supported dynamic electromagnetic torque calculation module is configured to perform comprehensive inertia control based on the real-time grid frequency and calculate the electromagnetic torque command required by the generator.

[0042] The additional load module under electromechanical-structural coupling is configured to calculate the pitch angular acceleration at the top of the tower and the additional inertial bending moment generated at the main shaft due to the pitch motion, based on the physical mechanism of the tower pitch caused by the generator reverse torque.

[0043] The dual-channel synchronous loading module is configured to drive and control the load motor system according to the electromagnetic torque command to simulate electromagnetic torque impact, superimpose the basic load component and additional inertial bending moment, and control the six-degree-of-freedom loading device to simulate the structural side vibration bending moment and achieve synchronous loading.

[0044] A wind turbine transmission chain test platform includes a drive motor system, a six-degree-of-freedom loading device, a transmission chain system, and a load motor system arranged sequentially, wherein the drive motor system is used to simulate the aerodynamic torque input of the wind turbine.

[0045] The six-degree-of-freedom loading device is used to simulate the non-torsional load on the wind turbine and the additional bending moment generated by the tower coupling;

[0046] Transmission chain system, used to transmit torque;

[0047] The load motor system is used to simulate the electromagnetic torque of a generator and the frequency response characteristics of the power grid;

[0048] This also includes the aforementioned electromechanical coupling loading system;

[0049] It may also include a controller for performing the steps of the above method.

[0050] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0051] This invention innovatively provides a dual-channel coupled loading strategy. By establishing a wind turbine frequency regulation control model, the electromagnetic torque command of the generator is calculated in real time according to the change of the power grid frequency to simulate power grid disturbances. The aim is to simulate the millisecond-level torque mutation caused by the wind turbine to support the power grid frequency when the frequency changes. A torque-tower coupled dynamic model is established to calculate the pitch motion of the tower caused by the electromagnetic torque mutation, and then calculate the inertial bending moment of the attachments on the main shaft, which is superimposed on the six-degree-of-freedom loading command. This achieves synchronous high-fidelity simulation of electrical side torque impact and structural side vibration bending moment.

[0052] This invention converts grid frequency disturbances into torque on the grid side of the drive train and additional loads under electromechanical-structural coupling, enabling a realistic reproduction of the process of grid fault → frequency support → torque mutation → tower sway → combined load acting on the main shaft. This not only compensates for the insufficient consideration of the impact of frequency fluctuations on grid-side torque and the lack of consideration for additional loads under electromechanical-structural coupling in the field of drive train testing technology, but also allows for the exploration of the dynamic response and potential risks of the drive train under frequency disturbance conditions. It provides a more realistic implementation scheme for the dynamic response analysis, structural design optimization, and reliability assessment of wind turbine drive trains under new power system frequency regulation conditions.

[0053] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0054] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0055] Figure 1 This is a schematic diagram of the electromechanical coupling loading method for a wind turbine drive train test platform provided in one embodiment.

[0056] Figure 2 This is a schematic diagram of a torque loading process under frequency support provided in one embodiment. Detailed Implementation

[0057] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0058] It should be noted that the following detailed description is illustrative and intended to provide further explanation of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0059] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0060] Where there is no conflict, the embodiments and features described in this application may be combined with each other.

[0061] Example 1

[0062] An electromechanical coupling loading method for a wind turbine drivetrain test platform, applied to a wind turbine drivetrain test platform, such as... Figure 1 As shown, it includes the following steps:

[0063] Obtain real-time wind speed and power grid frequency;

[0064] The dynamic nonlinear aerodynamic load, gravity load, and inertial load are calculated based on real-time wind speed and transformed through coordinate transformation to form the basic load components.

[0065] Based on the real-time power grid frequency, comprehensive inertia control is performed to calculate the electromagnetic torque command required by the generator.

[0066] Based on the physical mechanism of tower pitch caused by generator reverse torque, the pitch angular acceleration at the top of the tower is calculated, and the additional inertial bending moment generated at the main axis due to pitch motion is calculated.

[0067] According to the electromagnetic torque command, the load motor system is driven and controlled to simulate electromagnetic torque impact. The basic load component and additional inertial bending moment are superimposed to control the six-degree-of-freedom loading device to simulate the structural side vibration bending moment and achieve synchronous loading.

[0068] The following is a detailed introduction.

[0069] First, the method provided in this embodiment is applied to a wind turbine drivetrain test platform. The wind turbine drivetrain test platform can be an existing platform. The test platform, along the energy flow direction, consists of: a drive motor system, a six-degree-of-freedom loading device, a drivetrain system, and a load motor system, wherein:

[0070] The drive motor system is used to simulate the aerodynamic torque input of the wind turbine.

[0071] A six-degree-of-freedom loading device is used to simulate non-torsional loads (bending moment, shear force) on the wind turbine and additional bending moments generated by tower coupling.

[0072] The transmission chain system, including the main shaft, gearbox, etc., is used to transmit the generated torque;

[0073] Load motor system, used to simulate the electromagnetic torque of a generator and the frequency response characteristics of the power grid.

[0074] The structure of each part can use existing equipment and structures, and will not be described in detail here.

[0075] Wind turbines operate in complex environments, and during actual operation, the wind turbine generates nonlinear aerodynamic loads, gravity loads, and inertial loads. To effectively reproduce the wind turbine loads under different environments, the magnitudes of aerodynamic loads, gravity loads, and inertial loads are obtained using blade element-momentum theory. These loads are then decomposed into axial torque loads and five-degree-of-freedom non-torsional loads in other directions, and finally represented in the hub coordinate system through coordinate transformation. F x , F y , F z , M x , M y , M z ,in, F x The axial thrust in the main axis direction, F y This is the transverse shear force perpendicular to the principal axis. F z This is the vertical shear force perpendicular to the principal axis direction. M x Torque in the main axis direction.M y The pitching moment caused by wind shear, etc. M z This refers to the yaw moment caused by wind shear, etc.

[0076] The transmission chain ground test platform simulates torque loads through a load motor system and non-torque loads of the unit through hydraulic cylinder output. M x The load motor system in the ground test platform device is used for simulation, and the remaining five-degree-of-freedom non-torque load is simulated symmetrically by hydraulic loading in the ground test platform device.

[0077] In this embodiment, eight hydraulic cylinder loading points are equally distributed on the upwind and downwind planes of the loading disk, and eight loading points are equally distributed on the radial circumference of the loading disk. Symmetrical loading simulation is performed using the above 24 hydraulic loading points. All hydraulic cylinders only apply thrust and there is no coupling between the parameters.

[0078] The decomposition formula for a five-degree-of-freedom non-torsional load is shown below:

[0079] (1)

[0080] in F Ai Let be the axial loading force at the i-th loading point. F Ri Let be the radial loading force at the i-th loading point. r The loading radius.

[0081] The transmission chain ground loading test platform device conducts loading tests through a load motor system and a hydraulic cylinder device. When the power grid frequency fluctuates, the corresponding electromagnetic torque and six-degree-of-freedom load change with the frequency fluctuation to conduct loading tests, which can reproduce the load state of wind turbines in actual operation.

[0082] like Figure 2 As shown, when the grid frequency fluctuates, the wind turbine control system enters the frequency support mode. The wind turbine adopts integrated inertia control, which can achieve a frequency response capability similar to that of a synchronous generator. The control system calculates the corresponding dynamic electromagnetic power based on the frequency deviation and the frequency change rate.

[0083] Virtual inertia control modifies the active power output of the wind turbine based on the rate of frequency change, exhibiting rapid frequency response and effectively suppressing rapid frequency variations. Droop control, on the other hand, alters the active power output of the wind turbine based on frequency deviation, providing sustained power support for the system frequency over a longer period. Integrated inertia control combines virtual inertia control with droop control, using virtual inertia control to suppress rapid changes in system frequency and droop control to reduce system frequency deviation, thereby achieving better frequency regulation.

[0084] The frequency-modulated power obtained through integrated inertia control is superimposed with the power value obtained through maximum power point tracking (MPPT) control and used as the power reference value for the wind turbine. The frequency-modulated power obtained through integrated inertia control is:

[0085] (2)

[0086] In the formula Frequency modulation power for integrated inertia control; This is the virtual inertia coefficient, used to simulate inertia response; This is the droop control factor, used to simulate primary frequency modulation. For power grid frequency deviation, Let t be the rate of change of the power grid frequency, and t be time.

[0087] Since the wind turbine converter essentially controls current and thus torque, dividing the aforementioned frequency regulation power by the real-time speed yields the additional torque contribution required at this point. :

[0088] (3)

[0089] The rotor angular velocity is given by the total electromagnetic torque acting on the transmission chain. T e :

[0090] (4)

[0091] in:

[0092] (5)

[0093] T opt The base torque under MPPT control of the wind turbine unit. P opt This refers to the power output of the wind turbine under MPPT control.

[0094] When power grid frequency disturbances cause electromagnetic torque Te During a sudden change, the generator stator experiences a reaction torque of equal magnitude but opposite direction, driving the nacelle-tower system to pitch vibration. To simulate the electromechanical-tower coupling effect, a simplified torque-tower pitch dynamics model is introduced, while assuming that the electromagnetic torque... T e mutation amount T f It is the main excitation source causing the pitching vibration of the tower.

[0095] (6)

[0096] in , , , These are the equivalent moment of inertia coefficient, damping coefficient, stiffness coefficient, and pitch acceleration of the wind turbine tower, respectively.

[0097] The pitching motion of the tower will generate an additional inertial bending moment at the principal axis position. M add (Mainly manifested as the pitch moment about the Y-axis), resulting in an additional inertial pitch moment at the main bearing. M add for:

[0098] (7)

[0099] in J eq This is the equivalent moment of inertia of the transmission chain in the tower pitch direction.

[0100] Extensive field testing has yielded the additional inertial bending moment. M add Electromagnetic torque abrupt change T f Under certain external wind speed conditions, the nonlinear relationship can be represented in this embodiment by establishing a corresponding database with a large amount of data and using a lookup table method or establishing a function.

[0101] (8)

[0102] To accurately reproduce the above coupling effect, the calculated load components need to be correctly distributed to the actuators of the test bench.

[0103] In the ground test platform of the transmission chain, the continuous rotational torque of the spindle is executed by the load motor system, so the electromagnetic torque mutation does not need to be superimposed in the final execution command of the six-degree-of-freedom loading device. T f ;

[0104] The load motor channel (simulating electromagnetic torque) requires the load motor system to execute commands related to the total electromagnetic torque acting on the drive train. T e , T e The size is shown in formula (4). This channel simulates the sudden change in electromagnetic torque directly felt on the rotor side of the generator.

[0105] The six-degree-of-freedom platform – pitch channel (simulating electromechanical-structural coupling) – for the pitch moment channel affected by the electromechanical-structural coupling effect, its final execution command consists of two parts: one part is the basic aerodynamic pitch bending moment, and the other part is the additional inertial bending moment calculated based on the tower dynamics model.

[0106] The commands that the six-degree-of-freedom loading device needs to execute in the pitch direction are:

[0107] (9)

[0108] in M y The pitching moment of the foundation caused by aerodynamic factors such as wind shear. M add The additional inertial bending moment caused by the pitching vibration of the tower is calculated by formula (7).

[0109] Through this superposition, the six-degree-of-freedom loading device not only simulates the force of wind, but also simultaneously simulates the pitching moment of the main shaft caused by the instantaneous swaying of the tower when the power grid frequency fluctuation causes a sudden change in the electromagnetic torque of the generator, thus realistically reproducing the stress state of the main shaft bearing under complex working conditions.

[0110] The final execution command of the six-degree-of-freedom loading device is:

[0111] (10)

[0112] The final loading command for the transmission chain ground test platform is:

[0113] (11)

[0114] Through the above dual-channel loading, the ground loading test platform for the transmission chain achieves synchronous high-fidelity simulation of electrical-side torque impact and electromechanical-structural-side vibration bending moment, solving two significant defects of existing ground test platforms: lack of simulation of dynamic feedback of power grid frequency and neglect of electromechanical-structural coupling effect.

[0115] This embodiment can realistically reproduce the complete physical process of power grid fault → frequency support → torque mutation → tower sway → combined load acting on the main shaft. Compared with traditional tests that only simulate aerodynamic loads, it extends the boundary conditions of ground tests from a single wind side to a coupling of wind side, electrical side, and structural side, greatly improving the realism of the test.

[0116] This embodiment achieves accurate simulation of millisecond-level torque impact. By establishing a wind turbine frequency regulation control model and calculating the electromagnetic torque under frequency disturbances in real time, it can reproduce the millisecond-level torque mutation during the comprehensive inertia response. This effectively solves the problem that existing test benches simplify the load to a constant resistance torque, making it impossible to simulate the bidirectional extrusion impact on the spindle.

[0117] This embodiment reveals the additional loads induced by structural coupling: for the first time, an electromechanical-structural coupling channel is introduced, considering the torsional effect of the generator's reverse torque on the tower. By calculating the additional inertial bending moment generated by the tower's pitch motion and superimposing it on the six-degree-of-freedom loading device, potential main shaft failure and fatigue damage caused by tower vibration can be identified, providing a basis for long-life design of the drivetrain. This not only improves the accuracy of drivetrain life assessment but also provides experimental evidence for the structural optimization of wind turbine drivetrains in new power systems.

[0118] Example 2

[0119] An electromechanical coupling loading system for a wind turbine drivetrain test platform includes:

[0120] The data acquisition module is configured to acquire real-time wind speed and power grid frequency;

[0121] The basic aerodynamic load calculation module is configured to calculate dynamic nonlinear aerodynamic loads, gravity loads, and inertial loads based on real-time wind speed, and to form basic load components through coordinate transformation.

[0122] The frequency-supported dynamic electromagnetic torque calculation module is configured to perform comprehensive inertia control based on the real-time grid frequency and calculate the electromagnetic torque command required by the generator.

[0123] The additional load module under electromechanical-structural coupling is configured to calculate the pitch angular acceleration at the top of the tower and the additional inertial bending moment generated at the main shaft due to the pitch motion, based on the physical mechanism of the tower pitch caused by the generator reverse torque.

[0124] The dual-channel synchronous loading module is configured to drive and control the load motor system according to the electromagnetic torque command to simulate electromagnetic torque impact, superimpose the basic load component and additional inertial bending moment, and control the six-degree-of-freedom loading device to simulate the structural side vibration bending moment and achieve synchronous loading.

[0125] Example 3

[0126] A wind turbine transmission chain test platform includes a drive motor system, a six-degree-of-freedom loading device, a transmission chain system, and a load motor system arranged in sequence, wherein the drive motor system is used to simulate the aerodynamic torque input of the wind turbine.

[0127] The six-degree-of-freedom loading device is used to simulate the non-torsional load on the wind turbine and the additional bending moment generated by the tower coupling;

[0128] Transmission chain system, used to transmit torque;

[0129] The load motor system is used to simulate the electromagnetic torque of a generator and the frequency response characteristics of the power grid;

[0130] It also includes the electromechanical coupling loading system provided in Embodiment 2;

[0131] It may also include a controller for performing the steps of the method provided in Embodiment 1.

[0132] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of one or more computer-usable storage media (including, but not limited to, disk storage, etc.) containing computer-usable program code. CD - ROM It takes the form of a computer program product implemented on (such as optical memory, etc.).

[0133] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0134] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1The function specified in one or more boxes.

[0135] These computer program instructions can also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0136] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made by those skilled in the art without creative effort within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. An electromechanical coupling loading method for a wind turbine drivetrain test platform, characterized in that, Includes the following steps: Obtain real-time wind speed and power grid frequency; The dynamic nonlinear aerodynamic load, gravity load, and inertial load are calculated based on real-time wind speed and transformed through coordinate transformation to form the basic load components. Based on the real-time power grid frequency, comprehensive inertia control is performed to calculate the electromagnetic torque command required by the generator. Based on the physical mechanism of tower pitch caused by generator reverse torque, the process of calculating the pitch angular acceleration at the top of the tower includes: using electromagnetic torque T e mutation amount T f As the excitation source causing the pitch vibration of the tower; Calculations based on the torque-tower pitch dynamics model yielded the following: ； in, , , , These are the equivalent moment of inertia coefficient, damping coefficient, stiffness coefficient, and pitch acceleration of the wind turbine tower, respectively. The process of calculating the additional inertial bending moment generated at the principal axis due to pitch motion includes: the additional inertial pitch bending moment generated at the principal bearing. M add for: ； in, J eq This is the equivalent moment of inertia of the transmission chain in the tower pitch direction; According to the electromagnetic torque command, the load motor system is driven and controlled to simulate electromagnetic torque impact. The basic load component and additional inertial bending moment are superimposed to control the six-degree-of-freedom loading device to simulate the structural side vibration bending moment and achieve synchronous loading.

2. The electromechanical coupling loading method for a wind turbine drivetrain test platform as described in claim 1, characterized in that, The process of calculating dynamic nonlinear aerodynamic loads, gravity loads, and inertial loads based on real-time wind speed and transforming them into basic load components includes: obtaining the magnitudes of aerodynamic loads, gravity loads, and inertial loads based on real-time wind speed using blade element-momentum theory; decomposing the obtained loads into axial torque loads and five-degree-of-freedom non-torque loads in other directions; and then transforming them into the hub coordinate system.

3. The electromechanical coupling loading method for a wind turbine drivetrain test platform as described in claim 1, characterized in that, The wind turbine transmission chain test platform simulates torque load through a load motor system, simulates non-torque load through hydraulic cylinder output, and simulates the remaining five-degree-of-freedom non-torque load symmetrically through the hydraulic cylinder device in the wind turbine transmission chain test platform.

4. The electromechanical coupling loading method for a wind turbine drivetrain test platform as described in claim 1, characterized in that, The process of comprehensive inertia control based on real-time grid frequency includes: using virtual inertia control to change the active power output of the wind turbine according to the frequency change rate. By using droop control, the active power output of the wind turbine is changed according to the frequency deviation; Combining virtual inertia control and droop control forms a comprehensive inertia control system.

5. The electromechanical coupling loading method for a wind turbine drivetrain test platform as described in claim 1, characterized in that, The process of calculating the electromagnetic torque command required by the generator includes: obtaining the frequency-regulating power through integrated inertia control, and then superimposing it with the power value obtained from maximum power point tracking control as the power reference value for the wind turbine. The frequency-regulating power of integrated inertia control is: ； in, Frequency modulation power for integrated inertia control; This is the virtual inertia coefficient, used to simulate inertia response; This is the droop control factor, used to simulate primary frequency modulation. For power grid frequency deviation, Let t be the rate of change of the power grid frequency, and t be time. Divide the obtained frequency-modulated power by the real-time speed to obtain the additional torque increment required at this point. : ； The rotor angular velocity is the total electromagnetic torque that ultimately acts on the transmission chain. T e for: ； in, T opt This refers to the base torque under maximum power point tracking control of the wind turbine.

6. The electromechanical coupling loading method for a wind turbine drive train test platform as described in claim 1, characterized in that, The process of controlling the six-degree-of-freedom loading device by superimposing the basic load components and the additional inertial bending moment includes: the commands that the six-degree-of-freedom loading device needs to execute in the pitch direction are: ； in, M y The pitching moment of the foundation caused by aerodynamic factors. M add This is the calculated additional inertial bending moment caused by the pitching vibration of the tower.

7. An electromechanical coupling loading system for a wind turbine drivetrain test platform, characterized in that, The electromechanical coupling loading method for a wind turbine drive train test platform according to any one of claims 1-6 includes: The data acquisition module is configured to acquire real-time wind speed and power grid frequency; The basic aerodynamic load calculation module is configured to calculate dynamic nonlinear aerodynamic loads, gravity loads, and inertial loads based on real-time wind speed, and to form basic load components through coordinate transformation. The frequency-supported dynamic electromagnetic torque calculation module is configured to perform comprehensive inertia control based on the real-time grid frequency and calculate the electromagnetic torque command required by the generator. The additional load module under electromechanical-structural coupling is configured to calculate the pitch angular acceleration at the top of the tower and the additional inertial bending moment generated at the main shaft due to the pitch motion, based on the physical mechanism of the tower pitch caused by the generator reverse torque. The dual-channel synchronous loading module is configured to drive and control the load motor system according to the electromagnetic torque command to simulate electromagnetic torque impact, superimpose the basic load component and additional inertial bending moment, and control the six-degree-of-freedom loading device to simulate the structural side vibration bending moment and achieve synchronous loading.

8. A wind turbine drivetrain test platform, comprising a drive motor system, a six-degree-of-freedom loading device, a drivetrain system, and a load motor system arranged sequentially, wherein, The drive motor system is used to simulate the aerodynamic torque input of the wind turbine; The six-degree-of-freedom loading device is used to simulate the non-torsional load on the wind turbine and the additional bending moment generated by the tower coupling; Transmission chain system, used to transmit torque; The load motor system is used to simulate the electromagnetic torque of a generator and the frequency response characteristics of the power grid; Its characteristic is that it also includes the electromechanical coupling loading system for a wind turbine drive train test platform as described in claim 7; Alternatively, it may include a controller for performing the steps of the method according to any one of claims 1-6.

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