Tower front-back vibration resistance increasing method and device of large wind turbine generator

Abstract

The invention relates to the technical field of wind power generation, in particular to a tower front-back vibration resistance increasing method and device.The method comprises the steps that a nonlinear model is established based on a pre-established wind turbine generator considering tower front-back vibration, and an equivalent resistance increasing analysis result of a tower front-back vibration second-order dynamic equation is obtained; the tower vibration peak frequency at different rotating speeds is obtained according to the equivalent resistance increasing analysis result, so that the additional variable pitch rate used for tower resistance increasing is generated according to the tower vibration peak frequency, and vibration resistance increasing is conducted through the additional variable pitch rate. Therefore, the problems of inaccurate data transmission, high system complexity, insufficient algorithm adaptability, difficulty in implementation, high cost and the like due to sensor performance reduction caused by severe environment in related technologies are solved.

Description

Technical Field

[0001] The present application relates to the technical field of wind power generation, and in particular to a method and device for adding vibration damping to the front and rear of a tower of a large wind turbine generator set. Background Art

[0002] In the related art, the method of damping the front and rear vibrations of the tower of a large wind point unit usually involves installing monitoring equipment such as acceleration sensors and strain sensors on the tower to obtain the vibration state of the tower in real time and transmit these monitoring data to the controller. The controller calculates the control force to be applied based on a certain control algorithm, and then applies a reverse force to the tower through an actuator (such as a motor-driven variable pitch system or an additional actuator, etc.) to suppress the vibration.

[0003] However, in the related technologies, on the one hand, the harsh environment will affect the reliability and durability of the sensor, and it is easy to have performance degradation, damage and failure, resulting in inaccurate data, increased operation and maintenance costs and downtime, and data transmission is susceptible to interference and difficult to process; on the other hand, the actual working conditions are complex and changeable, the corresponding system complexity is high, the algorithm adaptability is insufficient, the cost is increased, and there are many failure risk points, which urgently need to be improved. Summary of the invention

[0004] The present application provides a method and device for adding vibration damping to the front and rear of a tower of a large wind turbine generator set, so as to solve the problems in the related art that the performance of the sensor is degraded due to the harsh environment, resulting in inaccurate transmission data, and the system is highly complex but the algorithm is not adaptable enough, which makes it difficult to implement and has high costs.

[0005] The first aspect of the present application provides a method for adding vibration damping to the front and rear of a tower of a large wind turbine, comprising the following steps: establishing a nonlinear model based on a pre-established wind turbine model that takes into account the front and rear vibration of the tower, and obtaining an equivalent resistance analysis result of the second-order dynamic equation of the front and rear vibration of the tower; obtaining the peak frequency of tower vibration at different rotation speeds based on the equivalent resistance analysis result; generating an additional pitch rate for tower resistance based on the peak frequency of tower vibration, so as to use the additional pitch rate for vibration resistance.

[0006] Through the above technical scheme, the embodiment of the present application can obtain the peak frequency of tower vibration based on the established nonlinear model and the equivalent resistance analysis results, and then generate an additional variable pitch rate for vibration resistance, effectively suppressing the front and rear vibration of the tower, enhancing the stability of the tower, and reducing the fatigue load caused by vibration, thereby reducing the operation and maintenance cost of the wind turbine and extending its service life.

[0007] Optionally, in one embodiment of the present application, the using the additional pitch rate to perform vibration damping includes: adding the additional pitch rate to a reference pitch rate for controlling the rotational speed to generate a total pitch rate command value.

[0008] Through the above technical solution, the embodiment of the present application can generate a total pitch rate command value by adding the additional pitch rate to the reference pitch rate used to control the rotational speed, thereby effectively integrating different pitch rates. On the one hand, the addition of the additional pitch rate brings additional adjustment factors to the system, which can more accurately adapt to different working conditions. On the other hand, the addition method is relatively simple and direct, and is easy to implement in the existing pitch rate control system. It can quickly realize the addition of the vibration damping function without completely changing the original reference pitch rate control logic, thereby improving the stability and reliability of the entire system in dealing with vibrations.

[0009] Optionally, in one embodiment of the present application, generating an additional pitch rate for tower resistance according to the tower vibration peak frequency includes: inputting at least one center frequency and at least one shear frequency of the tower vibration peak frequency into a preset proportional resonance controller respectively to output the additional pitch rate.

[0010] Through the above technical scheme, the embodiment of the present application can take the center frequency and shear frequency of the peak frequency of the tower vibration as input, accurately respond to the key characteristics of the tower vibration, and use a proportional resonant controller to output an additional pitch rate. With the help of the preset proportion and resonance function of the controller, the input frequency can be accurately processed and converted to generate a more appropriate and effective additional pitch rate, which helps to improve the effect of adding resistance to the tower, enhance the stability of the tower during operation, and reduce the risks and losses that may be caused by vibration.

[0011] Optionally, in one embodiment of the present application, the expression for establishing the nonlinear model of the wind turbine generator set is:

[0012]

[0013] Among them, Ω r is the wind wheel speed, T a is the aerodynamic torque, T e is the electromagnetic torque of the generator, x t is the tower top displacement, β is the uniform pitch angle, v0 is the effective wind speed of the wind rotor, G is the gearbox ratio, J is the equivalent moment of inertia, M t is the equivalent modal mass of the tower, C t is the structural damping of the tower, K t is the bending stiffness of the tower, F ais the aerodynamic thrust, i.e. the axial force of the wind rotor acting on the top of the tower, F1 is the wave load force equivalent to the top of the tower, F2 is the aerodynamic force from the wind directly acting on the tower equivalent to the top of the tower, T ac is the time constant of the pitch actuator, β * is the output command value of the pitch controller.

[0014] Through the above technical scheme, the embodiment of the present application can accurately present the complex dynamic characteristics of the actual operation of the wind turbine, cover the key degrees of freedom and mutual coupling relationships, accurately simulate nonlinear factors such as aerodynamic thrust and torque, and help optimize power tracking and improve power generation efficiency.

[0015] Optionally, in one embodiment of the present application, the calculation formula of the additional pitch rate is:

[0016]

[0017] in, is the output additional pitch rate of the i-th proportional resonant controller, ω ci is the shear frequency of the input i-th proportional resonant controller, ω i is the center frequency of the input i-th proportional resonant controller, x t is the tower top displacement, K Pi is the proportional control gain, K Ri is the resonance control gain.

[0018] Through the above technical scheme, the additional pitch rate calculation formula of the embodiment of the present application is obtained based on the characteristics of the front and rear vibration system of the tower and related analysis, and is proportional to the front and rear vibration acceleration of the tower. Therefore, the additional pitch rate can be easily calculated by monitoring the vibration acceleration, providing a direct and effective means for achieving precise vibration control.

[0019] The second aspect of the present application provides a front and rear vibration damping device for a tower of a large wind turbine, including: a first acquisition module, used to establish a nonlinear model based on a pre-established wind turbine taking into account the front and rear vibration of the tower, and obtain an equivalent damping analysis result of the second-order dynamic equation of the front and rear vibration of the tower; a second acquisition module, used to obtain the peak frequency of tower vibration at different speeds according to the equivalent damping analysis result; a vibration damping module, used to generate an additional pitch rate for tower damping according to the peak frequency of tower vibration, so as to use the additional pitch rate for vibration damping.

[0020] Through the above technical scheme, the embodiment of the present application can obtain the peak frequency of tower vibration based on the established nonlinear model and the equivalent resistance analysis results, and then generate an additional variable pitch rate for vibration resistance, effectively suppressing the front and rear vibration of the tower, enhancing the stability of the tower, and reducing the fatigue load caused by vibration, thereby reducing the operation and maintenance cost of the wind turbine and extending its service life.

[0021] Optionally, in one embodiment of the present application, the vibration damping module includes: a generating unit, configured to add the additional pitch rate to a reference pitch rate for controlling the rotation speed to generate a total pitch rate command value.

[0022] Through the above technical solution, the embodiment of the present application can generate a total pitch rate command value by adding the additional pitch rate to the reference pitch rate used to control the rotational speed, thereby effectively integrating different pitch rates. On the one hand, the addition of the additional pitch rate brings additional adjustment factors to the system, which can more accurately adapt to different working conditions. On the other hand, the addition method is relatively simple and direct, and is easy to implement in the existing pitch rate control system. It can quickly realize the addition of the vibration damping function without completely changing the original reference pitch rate control logic, thereby improving the stability and reliability of the entire system in dealing with vibrations.

[0023] Optionally, in one embodiment of the present application, the vibration damping module includes: an output unit, used to input at least one center frequency and at least one shear frequency of the tower vibration peak frequency into a preset proportional resonance controller respectively to output the additional pitch rate.

[0024] Through the above technical scheme, the embodiment of the present application can take the center frequency and shear frequency of the peak frequency of the tower vibration as input, accurately respond to the key characteristics of the tower vibration, and use a proportional resonant controller to output an additional pitch rate. With the help of the preset proportion and resonance function of the controller, the input frequency can be accurately processed and converted to generate a more appropriate and effective additional pitch rate, which helps to improve the effect of adding resistance to the tower, enhance the stability of the tower during operation, and reduce the risks and losses that may be caused by vibration.

[0025] Optionally, in one embodiment of the present application, the expression for establishing the nonlinear model of the wind turbine generator set is:

[0026]

[0027] Among them, Ω r is the wind wheel speed, T a is the aerodynamic torque, T e is the electromagnetic torque of the generator, x tis the tower top displacement, β is the uniform pitch angle, v0 is the effective wind speed of the wind rotor, G is the gearbox ratio, J is the equivalent moment of inertia, M t is the equivalent modal mass of the tower, C t is the structural damping of the tower, K t is the bending stiffness of the tower, F a is the aerodynamic thrust, i.e. the axial force of the wind rotor acting on the top of the tower, F1 is the wave load force equivalent to the top of the tower, F2 is the aerodynamic force from the wind directly acting on the tower equivalent to the top of the tower, T ac is the time constant of the pitch actuator, β * is the output command value of the pitch controller.

[0028] Through the above technical scheme, the embodiment of the present application can accurately present the complex dynamic characteristics of the actual operation of the wind turbine, cover the key degrees of freedom and mutual coupling relationships, accurately simulate nonlinear factors such as aerodynamic thrust and torque, and help optimize power tracking and improve power generation efficiency.

[0029] Optionally, in one embodiment of the present application, the calculation formula of the additional pitch rate is:

[0030]

[0031] in, is the output additional pitch rate of the i-th proportional resonant controller, ω ci is the shear frequency of the input i-th proportional resonant controller, ω i is the center frequency of the input i-th proportional resonant controller, x t is the tower top displacement, K Pi is the proportional control gain, K Ri is the resonance control gain.

[0032] Through the above technical scheme, the additional pitch rate calculation formula of the embodiment of the present application is obtained based on the characteristics of the front and rear vibration system of the tower and related analysis, and is proportional to the front and rear vibration acceleration of the tower. Therefore, the additional pitch rate can be easily calculated by monitoring the vibration acceleration, providing a direct and effective means for achieving precise vibration control.

[0033] The third aspect of the present application provides an electronic device, including: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the method for adding vibration damping to the front and rear of a tower of a large wind turbine as described in the above embodiment.

[0034] A fourth aspect of the present application provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, which, when executed by a processor, implements the above-mentioned method for adding damping to the front and rear vibrations of a tower of a large wind turbine.

[0035] The fifth aspect of the present application provides a computer program product, including a computer program, which, when executed, is used to implement the above-mentioned method for adding vibration damping to the front and rear of a tower of a large wind turbine generator set.

[0036] The embodiments of the present application can generate an additional pitch rate by obtaining the peak frequency of tower vibration through establishing a nonlinear model, which can suppress tower vibration, enhance stability, reduce fatigue load, reduce operation and maintenance costs and extend service life; the method of adding the additional pitch rate to the reference pitch rate is simple and effective to integrate different pitch rates, adapt to working conditions and improve stability; the additional pitch rate is output by inputting the proportional resonant controller with parameters related to the tower vibration frequency, which can improve the resistance effect; the operating characteristics of the wind turbine can be accurately presented, which is conducive to optimizing power tracking; the relationship between the additional pitch rate calculation formula and the vibration acceleration provides an effective means for precise vibration control.

[0037] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0039] Figure 1 A flowchart of a method for adding vibration resistance to a front and rear tower of a large wind turbine generator set according to an embodiment of the present application;

[0040] Figure 2 A schematic diagram of the control principle of a method for adding vibration damping to a front and rear tower of a large wind turbine according to an embodiment of the present application;

[0041] Figure 3 It is a schematic structural diagram of a front and rear vibration damping device for a tower of a large wind turbine generator set provided according to an embodiment of the present application;

[0042] Figure 4 The figure is a structural example diagram of an electronic device provided according to an embodiment of the present application. DETAILED DESCRIPTION

[0043] Embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present application, and should not be construed as limiting the present application.

[0044] The following describes the front and rear vibration damping method and device of the tower of a large wind turbine according to the embodiment of the present application with reference to the accompanying drawings. In view of the related technologies mentioned in the background technology center, due to the harsh environment, the sensor performance is reduced, which makes the transmission data inaccurate, and the system complexity is high but the algorithm adaptability is insufficient, so that it is difficult to implement and the cost is high. The present application provides a front and rear vibration damping method of the tower of a large wind turbine. In this method, the peak frequency of the tower vibration can be obtained based on the established nonlinear model and the equivalent resistance analysis results, and then an additional variable pitch rate is generated for vibration resistance, which effectively suppresses the front and rear vibration of the tower, enhances the stability of the tower, and reduces the fatigue load caused by vibration, thereby reducing the operation and maintenance cost of the wind turbine and extending its service life. There is no need to change the mechanical structure and electromagnetic torque controller of the wind turbine, only the pitch angle instruction needs to be added. At the same time, the controller can be designed according to the tower vibration phenomenon to suppress multiple vibration modes without the specific parameters of the wind turbine. Only one nonlinear controller can be designed to effectively control the full wind speed working area, so that the controller design is simple and efficient, and the dynamic performance is good, thereby improving the accuracy, economy and engineering practicality of the control. Thereby, the problems in the related technology of sensor performance degradation due to harsh environment, resulting in inaccurate data transmission, and high system complexity but insufficient algorithm adaptability, resulting in difficulty in implementation and high cost are solved.

[0045] Specifically, Figure 1 A schematic flow chart of a method for adding vibration damping to the front and rear of a tower of a large wind turbine generator set provided in an embodiment of the present application.

[0046] like Figure 1 As shown, the method for adding resistance to the front and rear vibrations of the tower of the large wind turbine generator set comprises the following steps:

[0047] In step S101, a nonlinear model of a wind turbine generator system considering the front-to-back vibration of a tower is established in advance, and an equivalent resistance analysis result of a second-order dynamic equation of the front-to-back vibration of the tower is obtained.

[0048] It can be understood that the simplified nonlinear model of the wind turbine includes two degrees of freedom, namely the front-to-back vibration mode of the tower and the rotation of the wind rotor. The control input of the wind turbine is the uniform pitch angle β, and the disturbance input is the effective wind speed v0 of the wind rotor. For high wind speed areas, the generator electromagnetic torque T e is the rated value, so it is not considered as the control input here. The output of the system includes the wind wheel speed Ω r and top speed Assume that they can all be measured directly.

[0049] Optionally, in one embodiment of the present application, the expression for establishing a nonlinear model of a wind turbine generator system includes:

[0050]

[0051] Formula (1) is the first-order dynamic model of the transmission system, Ω r is the wind wheel speed, T a is the aerodynamic torque, T e is the electromagnetic torque of the generator, x t is the displacement of the tower top, β is the uniform pitch angle, v0 is the effective wind speed of the wind rotor, G is the gearbox ratio, and J is the equivalent moment of inertia. Specifically, the equivalent moment of inertia J is the moment of inertia of the hub, blades and generator. h , J b , J g The sum is:

[0052] J=J h +3J b +J g ·G 2 (1.1)

[0053] Optionally, in one embodiment of the present application, the expression for establishing a nonlinear model of a wind turbine generator system includes:

[0054]

[0055] Formula (2) is the second-order dynamic equation of the tower forward and backward vibration, M t is the equivalent modal mass of the tower, C t is the structural damping of the tower, K t is the bending stiffness of the tower, F a is the aerodynamic thrust, that is, the axial force of the wind rotor acting on the top of the tower, F1 is the wave load force equivalent to the top of the tower, and F2 is the aerodynamic force from the wind directly acting on the tower equivalent to the top of the tower.

[0056] In actual implementation, the tower is subjected to forces from three parts: the axial force from the wind rotor acting on the top of the tower, the aerodynamic force from the wind directly acting on the tower, and the wave force from the waves acting on the bottom of the tower. When performing force analysis, the front and rear vibration system of the tower can be simplified to a cantilever beam model, i.e., equation (2).

[0057] Specifically, M t , C t , K t The calculation method is as follows:

[0058] M t =0.25mt +m n +m h +3m b (2.1)

[0059] C t =4πM t d s f0 (2.2)

[0060] K t =M t (2πf0) 2 (2.3)

[0061] Among them, m t is the mass of the tower, m n is the mass of the cabin, m h is the mass of the wheel hub, m b is the mass of the blade, d s is the structural damping ratio of the tower, and f0 is the natural frequency of the tower's front and rear vibration.

[0062] Optionally, in one embodiment of the present application, the expression for establishing a nonlinear model of a wind turbine generator system includes:

[0063]

[0064] Formula (3) is the dynamic model of the pitch actuator, which is equivalent to a first-order inertia link. ac is the time constant of the pitch actuator, β * is the output command value of the pitch controller.

[0065] It can be understood that the nonlinearity of the wind turbine model is mainly reflected in the expressions of aerodynamic torque and aerodynamic thrust:

[0066]

[0067] Where ρ is the air density, R is the radius of the wind wheel, C q is the aerodynamic torque coefficient, To consider the relative wind speed after the front and rear vibration of the tower, C t is the aerodynamic thrust coefficient, and both aerodynamic torque and aerodynamic thrust are non-affine nonlinear functions of λ and β. λ is the tip speed ratio, expressed as:

[0068]

[0069] The embodiment of the present application can establish a nonlinear model of a wind turbine that takes into account the front-to-back vibration of the tower, which can accurately describe the characteristics of the transmission system. At the same time, the second-order dynamic equation of the front-to-back vibration of the tower (Formula 2) takes into account the various forces borne by the tower, and a comprehensive force analysis helps to accurately simulate the vibration of the tower; in the model, reasonable calculation methods are given for parameters such as equivalent moment of inertia, equivalent modal mass of the tower, structural damping and bending stiffness. These calculations are based on actual parameters such as the mass of each part of the wind turbine, structural damping ratio and natural frequency, so that the model can be closer to the actual physical characteristics of the wind turbine, thereby improving the accuracy of the model. The control input and disturbance input of the wind turbine are clarified, and the output is determined. The dynamic model of the variable pitch actuator (Equation 3) is equivalent to the first-order inertia link. This clear definition of the control and output relationship is helpful to better design and optimize the control strategy of the wind turbine. It is accurately pointed out that the nonlinearity of the wind turbine model is mainly reflected in the expressions of aerodynamic torque and aerodynamic thrust (Equation 4 and Equation 5), and the influence of the tip speed ratio (Equation 6) is considered. This embodiment of nonlinear characteristics can more realistically reflect the complex situation of the wind turbine in actual operation, which is conducive to the in-depth study and optimization of the performance of the wind turbine.

[0070] In step S102, the peak frequency of tower vibration at different rotation speeds is obtained according to the equivalent resistance analysis result.

[0071] It can be understood that the equivalent resistance analysis results are based on the second-order dynamic equation of the tower front-to-back vibration in the nonlinear model of the wind turbine considering the tower front-to-back vibration. It is a summary of relevant information on how to equivalently increase the tower damping to suppress vibration through a series of analytical calculations. The peak frequency of tower vibration refers to the frequency corresponding to the maximum value of the vibration amplitude during the tower front-to-back vibration process.

[0072] In the actual implementation process, the influence of the changes of various parameters on the vibration characteristics of the tower at different speeds is analyzed. For example, it can be seen from equations (4) and (6) that the change of speed will affect the aerodynamic torque, and the tip speed ratio is related to the speed, which in turn changes the force acting on the tower and affects the vibration response of the tower.

[0073] In some cases, the modal equations of the tower front and rear vibration system can be solved, and the natural frequency and vibration mode of the system can be determined by calculating the eigenvalues ​​and eigenvectors of the system. Under different speed conditions, the natural frequency will also change due to changes in system parameters. By comparing the modal analysis results at different speeds, the peak frequency of the tower vibration can be identified. For example, when the speed increases, factors such as aerodynamic loads change, which may enhance the vibration response of a certain mode of the tower, and increase the vibration amplitude near the corresponding natural frequency, thereby determining the peak frequency of vibration at this speed.

[0074] In other cases, during the actual operation of the wind turbine, the vibration of the tower can be monitored in real time through sensors installed on the tower to obtain vibration data at different speeds. Perform spectrum analysis on the monitoring data to observe the energy distribution of the vibration signal on different frequency components. The frequency segment where the vibration energy is relatively concentrated may correspond to the peak frequency of the tower vibration. Combined with the results of theoretical analysis, the accurate peak frequency of the tower vibration at different speeds is verified and determined. For example, at high speeds, spectrum analysis finds that the vibration amplitude at a certain frequency is significantly higher than other frequencies, and is consistent with the vibration frequency that may occur at this speed in theoretical calculations, thereby determining that this frequency is the peak frequency of the tower vibration at high speeds.

[0075] Furthermore, from the tower dynamic model of equation (2), it can be seen that if a damping force command value F is superimposed on the existing force on the right side of the equation t , then the tower front and rear vibration equation can be expressed as:

[0076]

[0077] The system is controlled by a proportional controller, then the damping force command value F t satisfy:

[0078]

[0079] Where, ΔC t is the proportional coefficient of the proportional controller. Substituting equation (8) into equation (7), we get:

[0080]

[0081] It can be seen that proportional feedback control can effectively increase the damping of the front and rear vibrations of the tower and realize tower resistance. Different equivalent damping values ​​will change the vibration characteristics of the system. Larger equivalent damping may suppress vibrations of certain frequencies and transfer vibration energy to other frequencies. When analyzing the peak vibration frequency of the tower at different speeds, it is necessary to consider the impact of changes in equivalent damping on the vibration frequency and amplitude. For example, after increasing the equivalent damping at a certain speed, it is observed that the vibration peak of a higher frequency is reduced, while the vibration amplitude of another frequency is relatively increased, thereby determining the new vibration peak frequency.

[0082] The embodiments of the present application may take into account a variety of influencing factors, such as changes in rotation speed that affect the aerodynamic torque and thus change the force acting on the tower, thereby affecting the vibration response; the impact of changes in equivalent damping on the vibration frequency and amplitude. Different equivalent damping values ​​will change the vibration characteristics of the system, which will help to more comprehensively understand the vibration of the tower and make the analysis results closer to the actual situation.

[0083] In step S103, an additional pitch rate for tower damping is generated according to the peak frequency of tower vibration, so as to perform vibration damping by using the additional pitch rate.

[0084] It can be understood that the additional pitch rate is an additional pitch rate instruction applied to suppress the front and rear vibration of the tower. For example, when it is detected that the tower vibrates greatly at a certain vibration peak frequency, the appropriate additional pitch rate is calculated according to the corresponding control strategy, so that the blades adjust the pitch angle at this rate, change the aerodynamic performance of the wind wheel, and then suppress the vibration of the tower at this frequency. Vibration damping refers to the process of taking measures to increase the damping of the tower vibration system, thereby reducing the vibration amplitude of the tower.

[0085] Optionally, in one embodiment of the present application, an additional pitch rate for tower resistance is generated according to the peak frequency of tower vibration, including: inputting at least one center frequency and at least one shear frequency of the peak frequency of tower vibration into a preset proportional resonance controller respectively to output an additional pitch rate.

[0086] In the actual execution process, if the damping force command value F t As an additional aerodynamic thrust, we know that F t As a function of wind speed, rotation speed and blade angle, we have:

[0087]

[0088] From equations (8) and (10), we can get the additional pitch angle β t :

[0089]

[0090] Taking the derivative of both sides of equation (11), we can get the additional pitch rate:

[0091]

[0092] It can be seen that the additional pitch rate The acceleration of the tower's front and rear vibration Proportional relationship, can be obtained through get And it is input into the wind turbine system as a control variable. By analyzing the characteristics of the front and rear vibration system of the tower, we can obtain the n peak frequencies ω1, ω2, ..., ω of the front and rear vibration of the tower under different wind speeds. n , and the shear frequency ω used by the resistance controller c1 ,ω c2 ,…,ω cn .like Figure 2 As shown, the tower frame front and rear vibration acceleration Input parallel proportional resonant controller, can extract The frequency components that have the main influence on the vibration are obtained, and the additional pitch rate that has a targeted resistance effect on each component is obtained. Right now:

[0093]

[0094] in, is the output additional pitch rate of the i-th proportional resonant controller, ω ci is the shear frequency of the input i-th proportional resonant controller, ω i is the center frequency of the input i-th proportional resonant controller, x t is the tower top displacement, K Pi is the proportional control gain, K Ri is the resonance control gain.

[0095] Optionally, in one embodiment of the present application, vibration damping is performed using an additional pitch rate, including: adding the additional pitch rate to a reference pitch rate for controlling the rotational speed to generate a total pitch rate command value.

[0096] Specifically, the total pitch rate input to the wind turbine pitch controller is for:

[0097]

[0098] in, It is the basic pitch rate used to control the rotational speed and is output by the unified pitch controller.

[0099] The embodiment of the present application suppresses tower vibration by analyzing the peak frequency of tower vibration to generate an additional pitch rate, calculates the additional pitch rate taking into account multiple frequencies, ensures accuracy and complies with actual working conditions based on the relationship with variables such as vibration acceleration, and the additional pitch rate can be combined with the reference pitch rate to generate a total pitch rate command value, which is integrated into the overall control strategy, effectively taking into account both tower vibration suppression and speed control, and comprehensively and specifically controlling the vibration of the wind turbine tower. According to the method for adding vibration damping to the front and rear of the tower of a large wind turbine set proposed in the embodiment of the present application, the peak frequency of the tower vibration can be obtained based on the established nonlinear model and the equivalent resistance analysis results, and then an additional variable pitch rate is generated for vibration resistance, which effectively suppresses the front and rear vibration of the tower, enhances the stability of the tower, and reduces the fatigue load caused by vibration, thereby reducing the operation and maintenance cost of the wind turbine set and extending its service life. There is no need to change the mechanical structure and electromagnetic torque controller of the wind turbine set, only the pitch angle command needs to be added. At the same time, the controller can be designed according to the tower vibration phenomenon to suppress multiple vibration modes without the specific parameters of the wind turbine. Only one nonlinear controller needs to be designed to effectively control the full wind speed working area, so that the controller design is simple and efficient, with good dynamic performance, thereby improving the accuracy, economy and engineering practicality of the control.

[0100] Next, the front and rear vibration damping device for a tower of a large wind turbine generator set proposed in accordance with an embodiment of the present application will be described with reference to the accompanying drawings.

[0101] Figure 3 It is a block diagram of a front and rear vibration damping device for a tower of a large wind turbine generator set according to an embodiment of the present application.

[0102] like Figure 3 As shown, the tower front and rear vibration damping device 10 of the large wind turbine generator set includes: a first acquisition module 100, a second acquisition module 200 and a vibration damping module 300.

[0103] Specifically, the first acquisition module 100 is used to establish a nonlinear model based on a pre-established wind turbine group considering the front-to-back vibration of the tower, and obtain an equivalent resistance analysis result of a second-order dynamic equation of the front-to-back vibration of the tower.

[0104] The second acquisition module 200 is used to acquire the peak vibration frequency of the tower at different rotation speeds according to the equivalent resistance analysis result.

[0105] The vibration damping module 300 is used to generate an additional pitch rate for tower damping according to the peak frequency of tower vibration, so as to perform vibration damping by using the additional pitch rate.

[0106] Optionally, in one embodiment of the present application, the vibration damping module 300 includes: a generating unit, configured to add the additional pitch rate to a reference pitch rate for controlling the rotation speed to generate a total pitch rate command value.

[0107] Optionally, in one embodiment of the present application, the vibration damping module 300 includes: an output unit, used to input at least one center frequency and at least one shear frequency of the tower vibration peak frequency into a preset proportional resonance controller to output an additional pitch rate.

[0108] Optionally, in one embodiment of the present application, the expression for establishing a nonlinear model of a wind turbine generator system is:

[0109]

[0110] Among them, Ω r is the wind wheel speed, T a is the aerodynamic torque, T e is the electromagnetic torque of the generator, x t is the tower top displacement, β is the uniform pitch angle, v0 is the effective wind speed of the wind rotor, G is the gearbox ratio, J is the equivalent moment of inertia, M t is the equivalent modal mass of the tower, C t is the structural damping of the tower, K t is the bending stiffness of the tower, F a is the aerodynamic thrust, i.e. the axial force of the wind rotor acting on the top of the tower, F1 is the wave load force equivalent to the top of the tower, F2 is the aerodynamic force from the wind directly acting on the tower equivalent to the top of the tower, T ac is the time constant of the pitch actuator, β * is the output command value of the pitch controller.

[0111] Optionally, in one embodiment of the present application, the calculation formula of the additional pitch rate is:

[0112]

[0113] in, is the output additional pitch rate of the i-th proportional resonant controller, ω ci is the shear frequency of the input i-th proportional resonant controller, ω i is the center frequency of the input i-th proportional resonant controller, x t is the tower top displacement, K Pi is the proportional control gain, K Ri is the resonance control gain.

[0114] It should be noted that the above explanation of the embodiment of the method for adding vibration damping to the front and rear of the tower of a large wind turbine generator set is also applicable to the device for adding vibration damping to the front and rear of the tower of a large wind turbine generator set in this embodiment, and will not be repeated here.

[0115] According to the front and rear vibration damping device of the tower of a large wind turbine set proposed in the embodiment of the present application, the peak frequency of the tower vibration can be obtained based on the established nonlinear model and the equivalent damping analysis results, and then an additional variable pitch rate can be generated for vibration damping, which effectively suppresses the front and rear vibration of the tower, enhances the stability of the tower, and reduces the fatigue load caused by vibration, thereby reducing the operation and maintenance cost of the wind turbine set and extending its service life. There is no need to change the mechanical structure and electromagnetic torque controller of the wind turbine set, only the pitch angle instruction needs to be added. At the same time, the controller can be designed according to the tower vibration phenomenon to suppress multiple vibration modes without the specific parameters of the wind turbine. Only one nonlinear controller needs to be designed to effectively control the full wind speed working area, so that the controller design is simple and efficient, with good dynamic performance, thereby improving the accuracy, economy and engineering practicality of the control.

[0116] Figure 4 A schematic diagram of the structure of an electronic device provided in an embodiment of the present application. The electronic device may include:

[0117] Memory 401 , processor 402 , and a computer program stored in the memory 401 and executable on the processor 402 .

[0118] When the processor 402 executes the program, the method for adding resistance to the front and rear vibrations of the tower of a large wind turbine generator set provided in the above embodiment is implemented.

[0119] Furthermore, the electronic device further comprises:

[0120] The communication interface 403 is used for communication between the memory 401 and the processor 402 .

[0121] The memory 401 is used to store computer programs that can be executed on the processor 402 .

[0122] The memory 401 may include a high-speed RAM memory, and may also include a non-volatile memory (non-volatile memory), such as at least one disk memory.

[0123] If the memory 401, the processor 402 and the communication interface 403 are implemented independently, the communication interface 403, the memory 401 and the processor 402 can be connected to each other through a bus and communicate with each other. The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus or an Extended Industry Standard Architecture (EISA) bus. The bus can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, Figure 4 Only one thick line is used in the diagram, but this does not mean that there is only one bus or only one type of bus.

[0124] Optionally, in a specific implementation, if the memory 401, the processor 402 and the communication interface 403 are integrated on a chip, the memory 401, the processor 402 and the communication interface 403 can communicate with each other through an internal interface.

[0125] The processor 402 may be a central processing unit (CPU), or an application specific integrated circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of the present application.

[0126] The embodiment of the present application also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the method for adding vibration damping to the front and rear of a tower of a large wind turbine generator set as described above.

[0127] The embodiment of the present application also provides a computer program product, including a computer program, which, when executed, is used to implement the above-mentioned method for adding vibration damping to the front and rear of a tower of a large wind turbine generator set.

[0128] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or N embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0129] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of this application, "N" means at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0130] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, fragment or portion of code comprising one or N executable instructions for implementing the steps of a custom logical function or process, and the scope of the preferred embodiments of the present application includes alternative implementations in which functions may not be performed in the order shown or discussed, including performing functions in a substantially simultaneous manner or in reverse order depending on the functions involved, which should be understood by technicians in the technical field to which the embodiments of the present application belong.

[0131] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as an ordered list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by an instruction execution system, device or apparatus (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, device or apparatus and execute instructions), or in combination with these instruction execution systems, devices or apparatuses. For the purpose of this specification, "computer-readable medium" can be any device that can contain, store, communicate, propagate or transmit a program for use by an instruction execution system, device or apparatus, or in combination with these instruction execution systems, devices or apparatuses. More specific examples of computer-readable media (a non-exhaustive list) include the following: an electrical connection with one or N wirings (electronic devices), a portable computer disk box (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), a fiber optic device, and a portable compact disk read-only memory (CDROM). In addition, the computer-readable medium may even be paper or other suitable medium on which the program is printed, since the program may be obtained electronically by optically scanning the paper or other medium and then editing, interpreting or processing in other suitable ways as necessary and then storing it in a computer memory.

[0132] It should be understood that the various parts of the present application can be implemented by hardware, software, firmware or a combination thereof. In the above embodiment, the N steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. If implemented by hardware, as in another embodiment, it can be implemented by any one or a combination of multiple of the following technologies known in the art: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0133] A person skilled in the art may understand that all or part of the steps in the method for implementing the above-mentioned embodiment may be completed by instructing related hardware through a program, and the program may be stored in a computer-readable storage medium, which, when executed, includes one or a combination of the steps of the method embodiment.

[0134] In addition, each functional unit in each embodiment of the present application may be integrated into a processing module, or each unit may exist physically separately, or two or more units may be integrated into one module. The above-mentioned integrated module may be implemented in the form of hardware or in the form of a software functional module. If the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it may also be stored in a computer-readable storage medium.

[0135] The storage medium mentioned above may be a read-only memory, a magnetic disk or an optical disk, etc. Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limiting the present application. A person of ordinary skill in the art may change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A method for adding vibration damping to the front and rear of a tower of a large wind turbine generator set, characterized in that: The following steps are involved: A nonlinear model of the wind turbine considering the front and rear vibration of the tower is established in advance to obtain the equivalent resistance analysis results of the second-order dynamic equation of the front and rear vibration of the tower; According to the equivalent resistance analysis result, the peak vibration frequency of the tower at different rotation speeds is obtained; An additional pitch rate for tower damping is generated according to the tower vibration peak frequency, so as to perform vibration damping by using the additional pitch rate.

2. The method according to claim 1, characterized in that The step of using the additional pitch rate to perform vibration damping includes: The additional pitch rate is added to a reference pitch rate for controlling the rotational speed to generate a total pitch rate command value.

3. The method according to claim 1, characterized in that The generating an additional pitch rate for tower resistance according to the tower vibration peak frequency comprises: At least one center frequency and at least one shear frequency of the tower vibration peak frequency are respectively input into a preset proportional resonance controller to output the additional pitch rate.

4. The method according to claim 1, characterized in that The expression for establishing the nonlinear model of the wind turbine generator set is: Among them, Ω r is the wind wheel speed, T a is the aerodynamic torque, T e is the electromagnetic torque of the generator, x t is the tower top displacement, β is the uniform pitch angle, v0 is the effective wind speed of the wind rotor, G is the gearbox ratio, J is the equivalent moment of inertia, M t is the equivalent modal mass of the tower, C t is the structural damping of the tower, K t is the bending stiffness of the tower, F a is the aerodynamic thrust, i.e. the axial force of the wind rotor acting on the top of the tower, F1 is the wave load force equivalent to the top of the tower, F2 is the aerodynamic force from the wind directly acting on the tower equivalent to the top of the tower, T ac is the time constant of the pitch actuator, β * is the output command value of the pitch controller.

5. The method according to claim 4, characterized in that The calculation formula of the additional pitch rate is: in, is the output additional pitch rate of the i-th proportional resonant controller, ω ci is the shear frequency of the input i-th proportional resonant controller, ω i is the center frequency of the input i-th proportional resonant controller, x t is the tower top displacement, K Pi is the proportional control gain, K Ti is the resonance control gain.

6. A front and rear vibration damping device for a tower of a large wind turbine generator set, characterized in that: include: The first acquisition module is used to establish a nonlinear model based on a pre-established wind turbine group considering the front and rear vibration of the tower, and obtain an equivalent resistance analysis result of a second-order dynamic equation of the front and rear vibration of the tower; A second acquisition module is used to acquire the peak vibration frequency of the tower at different rotation speeds according to the equivalent resistance analysis result; The vibration damping module is used to generate an additional pitch rate for tower damping according to the peak frequency of tower vibration, so as to perform vibration damping by using the additional pitch rate.

7. The device according to claim 6, characterized in that The vibration damping module comprises: A generating unit is used to add the additional pitch rate to a reference pitch rate for controlling the rotation speed to generate a total pitch rate command value.

8. An electronic device, characterized in that: include: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the method for adding vibration damping to the front and rear of a tower of a large wind turbine as described in any one of claims 1 to 5.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: The program is executed by a processor to implement the method for adding vibration damping to the front and rear of a tower of a large wind turbine generator set as described in any one of claims 1 to 5.

10. A computer program product, comprising a computer program, characterized in that The computer program is executed to implement the method for adding damping to the front and rear vibrations of a tower of a large wind turbine generator set according to any one of claims 1 to 5.

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