Complete machine load identification and control method, device, equipment and medium

Abstract

The invention discloses a complete machine load identification and control method and device, equipment and a medium, and relates to the technical field of wind power. The method comprises the following steps: measuring blade root bending moments of three blades of the wind turbine generator in real time, and determining a variable pitch mechanism bending moment based on the blade root bending moments and a real-time pitch angle; hub center bending moments under different hub coordinate systems are determined based on the blade cone angle, the wind wheel azimuth angle and the variable pitch mechanism bending moment; determining a cabin bending moment under a tower top coordinate system based on the cabin gravity center, the cabin weight and the hub center bending moment of the wind turbine generator; determining the wind wheel thrust of the wind turbine generator by using the blade root bending moment, and determining the tower bottom pitching moment under the tower bottom coordinate system based on the wind wheel thrust and the cabin bending moment; and when it is monitored that the measured target key load triggers a preset load control strategy, the whole wind turbine generator is controlled to enter an adjustment link so as to control the target key load. According to the technical scheme, the safety of the tower structure of the wind turbine generator is guaranteed, and the maintenance level is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of wind power generation, and particularly to a method, device, equipment and medium for identifying and controlling the overall load of a wind turbine generator set. Background Art

[0002] The overall load of a wind turbine generator set is complex, with numerous influencing factors and obvious non-linear characteristics. The load simulated based on a low-fidelity simulation model is difficult to accurately evaluate the actual load-bearing situation of a rigid-flexible coupled prototype unit under complex site conditions. In terms of testing, there are problems that the key loads of the whole machine cannot be directly measured or cannot be measured with low cost, high reliability and for a long time. Since the load levels and remaining service lives of the key components of the whole machine are unknown, it is difficult to support the closed-loop design of the overall load, control load reduction, increase power generation and extend the service life of the unit in the later stage. Therefore, how to effectively identify and control the overall load of the wind turbine generator set and improve the structural safety and load management level of the wind turbine generator set is a problem that those skilled in the art need to solve at present. Summary of the Invention

[0003] In view of this, the purpose of the present invention is to provide a method, device, equipment and medium for identifying and controlling the overall load of a wind turbine generator set, which can effectively identify and control the key load levels of the whole machine, and is beneficial to ensuring the structural safety of the tower of the wind turbine generator set and improving the maintenance level. The specific solutions are as follows:

[0004] In a first aspect, the present application discloses a method for identifying and controlling the overall load of a wind turbine generator set, including:

[0005] Measuring the root bending moments of the three blades of the wind turbine generator set in real time, and determining the pitch mechanism bending moment based on the root bending moments and the real-time pitch angles of the three blades;

[0006] Determining the blade cone angles and the wind turbine azimuth angles of the three blades, and determining the hub center bending moments in different hub coordinate systems based on the blade cone angles, the wind turbine azimuth angles and the pitch mechanism bending moments;

[0007] Determining the center of gravity and weight of the nacelle of the wind turbine generator set, and determining the nacelle bending moment in the tower top coordinate system based on the center of gravity of the nacelle, the weight of the nacelle and the hub center bending moments;

[0008] Determining the wind turbine thrust of the wind turbine generator set by using the root bending moments, and determining the tower bottom pitching moment in the tower bottom coordinate system based on the wind turbine thrust and the nacelle bending moment;

[0009] Determining the target key loads of the wind turbine generator set by using the root bending moments, the pitch mechanism bending moments, the hub center bending moments, the nacelle bending moments, the wind turbine thrust and the tower bottom pitching moments, and when it is monitored that the target key loads trigger a pre-set load control strategy, controlling the whole machine of the wind turbine generator set to enter an adjustment link to control the target key loads.

[0010] Optionally, the method for measuring the root bending moments of the three blades of a wind turbine in real time and determining the pitch mechanism bending moment based on the root bending moments and the real-time pitch angles of the three blades includes:

[0011] Measuring the root flap bending moment and the root edgewise bending moment of the three blades of the wind turbine in real time through a fiber optic sensor or a cantilever sensor;

[0012] Determining the in-plane bending moment and the out-of-plane bending moment of the pitch mechanism respectively based on the root flap bending moment, the root edgewise bending moment and the real-time pitch angles of the three blades;

[0013] Among them, the calculation formulas for the in-plane bending moment and the out-of-plane bending moment are:

[0014] ;

[0015] is the in-plane bending moment, is the out-of-plane bending moment; is the root edgewise bending moment, is the root flap bending moment; is the real-time pitch angle of the three blades; represents the three blades of the wind turbine.

[0016] Optionally, the method for determining the blade cone angles and the wind turbine azimuth angles of the three blades and determining the hub center bending moment in different hub coordinate systems based on the blade cone angles, the wind turbine azimuth angles and the pitch mechanism bending moment includes:

[0017] Determining the blade cone angles of the three blades and determining the first hub center bending moment in the rotating hub coordinate system based on the pitch mechanism bending moment;

[0018] Determining the wind turbine azimuth angles of the three blades and determining the second hub center bending moment in the fixed hub coordinate system based on the wind turbine azimuth angles and the first hub center bending moment;

[0019] Among them, the calculation formula for the first hub center bending moment is:

[0020] ;

[0021] , , are the components of the first hub center bending moment on the x-axis, y-axis and z-axis in the rotating hub coordinate system respectively; , are the in-plane bending moment and the out-of-plane bending moment of the pitch mechanism respectively, represents the three blades of the wind turbine; is the blade taper angle of the three blades;

[0022] The calculation formula for the second hub center bending moment is:

[0023] ;

[0024] , , are the second hub center bending moment components on the x-axis, y-axis, and z-axis in the fixed hub coordinate system, respectively; is the wind turbine azimuth angle, defined as the orientation angle of the first blade.

[0025] Optionally, the calculation formula for the nacelle bending moment in the tower top coordinate system is:

[0026] ;

[0027] where, , , are the nacelle bending moment components on the x-axis, y-axis, and z-axis in the tower top coordinate system, respectively; , , is the hub center bending moment in the fixed hub coordinate system; is the drive train inclination angle; is the nacelle weight, is the nacelle center of gravity, g is the acceleration due to gravity, is the wind turbine weight, is the wind turbine thrust, is the front-back distance of the hub center relative to the tower top center, is the vertical distance of the hub center relative to the tower top center.

[0028] Optionally, determining the wind turbine thrust of the wind turbine using the root bending moment and determining the tower bottom pitching moment in the tower bottom coordinate system based on the wind turbine thrust and the nacelle bending moment includes:

[0029] Determining the wind turbine thrust of the wind turbine using the root flap bending moment; the calculation formula for the wind turbine thrust is: ; where a and b are the least squares linearization coefficients obtained based on the root flap bending moment and the root thrust load simulation data, is the root flap bending moment;

[0030] Determining the tower bottom pitching moment in the tower bottom coordinate system based on the wind turbine thrust and the nacelle bending moment; the calculation formula for the tower bottom pitching moment is: ; is the drive train inclination angle, h is the tower height, is the component of the nacelle bending moment on the y-axis in the tower top coordinate system, is the nacelle weight, is the measured acceleration of the nacelle in the front-back direction.

[0031] Optionally, when it is detected that the target key load triggers a preset load control strategy, controlling the entire wind turbine to enter an adjustment stage to control the target key load includes:

[0032] Determining the design value corresponding to the entire wind turbine and the target key load through simulation, and setting the load thresholds of each load in the target key load in the unit controller of the wind turbine according to the design value;

[0033] When it is detected that any load in the target key load exceeds the load threshold, taking blade pitch-changing measures and power limiting measures, and when it is detected that the target key load meets the preset exit condition, controlling the entire wind turbine to enter the normal operation stage.

[0034] Optionally, after controlling the entire wind turbine to enter the adjustment stage to control the target key load, it further includes:

[0035] Processing the load time history of the target key load by the rainflow counting method to determine the equivalent fatigue load and remaining life of the target component in the entire wind turbine;

[0036] Formulating corresponding operation and maintenance measures for the target component according to the equivalent fatigue load and the remaining life;

[0037] Wherein, the calculation formula of the equivalent fatigue load is: ; is the load amplitude is the number of cycles at the load amplitude, n is the number of load amplitude intervals, and m is the reverse slope of the material S-N curve;

[0038] The calculation formula of the remaining life is: ; C is the material fatigue constant, is the total fatigue life.

[0039] In a second aspect, the present application discloses a device for identifying and controlling the load of the entire machine, including:

[0040] A first load identification module, configured to measure the root bending moment of the three blades of the wind turbine in real time, and determine the pitch-changing mechanism bending moment based on the root bending moment and the real-time pitch angles of the three blades;

[0041] A second load identification module, configured to determine the blade cone angles and the wind turbine azimuth angles of the three blades, and determine the hub center bending moments in different hub coordinate systems based on the blade cone angles, the wind turbine azimuth angles, and the pitch mechanism bending moments;

[0042] A third load identification module, configured to determine the nacelle center of gravity and the nacelle weight of the wind turbine, and determine the nacelle bending moment in the tower top coordinate system based on the nacelle center of gravity, the nacelle weight, and the hub center bending moments;

[0043] A fourth load identification module, configured to determine the wind turbine thrust of the wind turbine by using the root bending moment, and determine the tower bottom pitching moment in the tower bottom coordinate system based on the wind turbine thrust and the nacelle bending moment;

[0044] A load control module, configured to determine the target key loads of the wind turbine by using the root bending moment, the pitch mechanism bending moment, the hub center bending moment, the nacelle bending moment, the wind turbine thrust, and the tower bottom pitching moment, and when it is monitored that the target key loads trigger a preset load control strategy, control the entire wind turbine to enter an adjustment link to control the target key loads.

[0045] In a third aspect, the present application discloses an electronic device, which includes a processor and a memory; wherein, the memory is used to store a computer program, and the computer program is loaded and executed by the processor to implement the method for identifying and controlling the overall machine load as described above.

[0046] In a fourth aspect, the present application discloses a computer-readable storage medium, which is used to store a computer program; wherein the computer program implements the method for identifying and controlling the overall machine load as described above when executed by a processor.

[0047] The present application provides a method for identifying and controlling the overall load of a wind turbine, including: measuring the root bending moments of the three blades of the wind turbine in real time, and determining the pitch mechanism bending moment based on the root bending moments and the real-time pitch angles of the three blades; determining the blade cone angles and the wind turbine azimuth angles of the three blades, and determining the hub center bending moments in different hub coordinate systems based on the blade cone angles, the wind turbine azimuth angles, and the pitch mechanism bending moment; determining the nacelle center of gravity and the nacelle weight of the wind turbine, and determining the nacelle bending moment in the tower top coordinate system based on the nacelle center of gravity, the nacelle weight, and the hub center bending moment; determining the wind turbine thrust of the wind turbine using the root bending moments, and determining the tower bottom pitching moment in the tower bottom coordinate system based on the wind turbine thrust and the nacelle bending moment; determining the target key loads of the wind turbine using the root bending moments, the pitch mechanism bending moment, the hub center bending moment, the nacelle bending moment, the wind turbine thrust, and the tower bottom pitching moment, and when it is monitored that the target key loads trigger a pre-set load control strategy, controlling the entire wind turbine to enter an adjustment process to control the target key loads.

[0048] The beneficial effects of the present application are as follows: By measuring the root bending moments, the pitch mechanism bending moment, the hub center bending moment, the nacelle bending moment, the wind turbine thrust, and the tower bottom pitching moment, the target key loads that the entire wind turbine needs to obtain are determined. Using the target key loads can effectively identify and control the key load levels of the entire machine, which is beneficial to ensuring the safety of the wind turbine tower structure and improving the maintenance level.

[0049] In addition, a device, equipment, and storage medium for identifying and controlling the overall load provided by the present application correspond to the above method for identifying and controlling the overall load, and have the same effects. Description of the Drawings

[0050] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only the embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained according to the provided drawings without creative efforts.

[0051] Figure 1 It is a flowchart of a method for identifying and controlling the overall load disclosed in the present application;

[0052] Figure 2 It is an online intelligent control logic diagram of 22 key loads in 7 groups for the overall machine disclosed in the present application;

[0053] Figure 3 It is a schematic diagram of the overall system process for online identification and control of the overall load disclosed in the present application;

[0054] Figure 4 A comparison diagram of hub torque time series for simulation and recognition disclosed in this application;

[0055] Figure 5 A comparison diagram of nacelle bending moment time series in the tower top coordinate system for simulation and recognition disclosed in this application;

[0056] Figure 6 A comparison diagram of pitch moment time series in the tower bottom coordinate system for simulation and recognition disclosed in this application;

[0057] Figure 7 A schematic structural diagram of an identification and control device for the overall machine load disclosed in this application;

[0058] Figure 8 A structural diagram of an electronic device disclosed in this application. Detailed implementation manners

[0059] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0060] The overall machine load of a wind turbine is complex, with many influencing factors and obvious non-linear characteristics. At present, the load simulated based on a low-fidelity simulation model is difficult to accurately evaluate the actual load-bearing situation of a rigid-flexible coupled full-scale unit under complex site conditions. In terms of testing, there are problems that the key loads of the overall machine cannot be directly measured or cannot be measured with low cost, high reliability, and long term.

[0061] Therefore, this application provides an identification and control solution for the overall machine load, which can effectively identify and control the key load levels of the overall machine, and improve the structural safety and load management level of the wind turbine.

[0062] An embodiment of the present invention discloses an identification and control method for the overall machine load. Refer to Figure 1 As shown, this method includes:

[0063] Step S11: Measure the root bending moment of the three blades of the wind turbine in real time, and determine the pitch mechanism bending moment based on the root bending moment and the real-time pitch angles of the three blades.

[0064] In the embodiments of this application, both fiber optic sensors and cantilever sensors are suitable for the long-term measurement of root bending moment. Therefore, the root bending moment of the three blades of the wind turbine is measured in real time through fiber optic sensors or cantilever sensors. Among them, fiber optic sensors have higher costs and more reliable and accurate measurements; while cantilever sensors have low costs, but there may be some errors in measurements.

[0065] In the embodiments of the present application, the first set of key loads for the entire machine in measurement and identification is the root bending moment of the blade, including two key loads: the root flap bending moment and the root edgewise bending moment. The root flap bending moment is generated by the flap motion of the blade. The flap motion refers to the front-back vibration of the blade around its rotation axis, and this vibration will cause a bending load at the blade root. The root edgewise bending moment is generated by the edgewise motion of the blade. The edgewise motion refers to the lateral vibration of the blade around its rotation axis, and this vibration will also cause a bending load at the blade root.

[0066] Generally, only the root flap bending moment is measured at the blade root , which mainly reflects the aerodynamic load on the blade, while the root edgewise bending moment mainly reflects the gravitational load on the blade. The aerodynamic load and the gravitational load are the main load sources of the entire wind turbine. Therefore, in order to identify the key loads of the entire machine, the root flap bending moments and the root edgewise bending moments of the three blades of the unit must be measured.

[0067] On this basis, combined with the real-time pitch angles of the three blades, the second set of key loads for the entire machine, the pitch mechanism bending moment, is calculated. Among them, the pitch mechanism bending moment includes the in-plane bending moment and the out-of-plane bending moment of the pitch mechanism, which are two key loads and can be used to evaluate the load conditions of the pitch mechanism. The calculation formula is as follows:

[0068] ; where represents the three blades of the wind turbine.

[0069] It can be seen that after step S11, two sets of 4 key loads are measured and identified, namely the root flap bending moment , the root edgewise bending moment , the in-plane bending moment of the pitch mechanism, and the out-of-plane bending moment of the pitch mechanism. Therefore, for the three blades of the entire machine, there are a total of two sets of 12 key loads.

[0070] Step S12: Determine the blade cone angle and the wind turbine azimuth angle of the three blades, and determine the hub center bending moment in different hub coordinate systems based on the blade cone angle, the wind turbine azimuth angle, and the pitch mechanism bending moment.

[0071] In the embodiments of the present application, the blade cone angle refers to the inclination angle of the blade center line relative to the rotation axis, which is usually used to describe the geometric characteristics of the blade in a wind turbine or other rotating machinery. It reflects the degree of front-back inclination of the blade. When synthesizing the blade loads to the hub, the blade cone angle needs to be considered.

[0072] In the embodiments of the present application, the hub center bending moments in the rotating hub coordinate system and the fixed hub coordinate system are respectively calculated by combining the blade cone angles of the three blades and the azimuth angle of the wind turbine. Specifically:

[0073] First, based on the pitch mechanism bending moment, the first hub center bending moment in the rotating hub coordinate system is synthesized by combining the blade cone angles. It should be noted that the three blades of the wind turbine are evenly distributed at 120° intervals, and the angles between the second blade, the third blade and the first blade are 120° and 240° respectively. Then, the first hub bending moment in the rotating hub coordinate system is calculated according to the following formula:

[0074] ;

[0075] , , are the components of the first hub center bending moment on the x-axis, y-axis and z-axis in the rotating hub coordinate system respectively; , are the in-plane bending moment and out-of-plane bending moment of the pitch mechanism respectively, represents the three blades of the wind turbine; is the blade cone angle of the three blades.

[0076] Furthermore, based on the azimuth angle of the wind turbine and the first hub center bending moment, the second hub center bending moment in the fixed hub coordinate system is obtained. In the embodiments of the present application, the azimuth angle of the wind turbine is defined as the orientation angle of the first blade, and the azimuth angle of the wind turbine can be obtained in real time through the slip ring device of the wind turbine. Then, the second hub center bending moment in the fixed hub coordinate system is calculated according to the following formula:

[0077] ;

[0078] , , are the components of the second hub center bending moment on the x-axis, y-axis and z-axis in the fixed hub coordinate system respectively; is the azimuth angle of the wind turbine, defined as the orientation angle of the first blade.

[0079] It can be seen that after step S12, the key loads measured and identified are the hub center bending moments , , in the rotating hub coordinate system and the hub center bending moments , , in the fixed hub coordinate system. Since in the rotating hub coordinate system and the fixed hub coordinate system and are the same. Therefore, after step S12, a total of 5 key loads in two groups of the whole machine are measured and identified.

[0080] Step S13: Determine the nacelle center of gravity and the nacelle weight of the wind turbine, and determine the nacelle bending moment in the tower top coordinate system based on the nacelle center of gravity, the nacelle weight, and the hub center bending moment.

[0081] In the embodiment of the present application, the sources of the nacelle bending moment load in the tower top coordinate system mainly include the hub and the nacelle. The hub load is identified by step S12. When converting it to the tower top coordinate system, the drive train inclination and the additional bending moment need to be considered. And the nacelle center of gravity usually does not coincide with the tower top center, resulting in a bending moment generated by its gravity load. The nacelle bending moment load in the tower top coordinate system is calculated as follows:

[0082] ;

[0083] where , , are the nacelle bending moment components on the x-axis, y-axis, and z-axis in the tower top coordinate system respectively; , , is the hub center bending moment in the fixed hub coordinate system; is the drive train inclination; is the nacelle weight, is the nacelle center of gravity, g is the acceleration due to gravity, is the rotor weight, is the rotor thrust, is the front-back distance of the hub center relative to the tower top center, is the vertical distance of the hub center relative to the tower top center.

[0084] It can be seen that after step S13, a total of 3 key loads in one group of the whole machine are measured and identified, which are the nacelle bending moment in the tower top coordinate system , , .

[0085] Step S14: Use the blade root bending moment to determine the rotor thrust of the wind turbine, and determine the tower bottom pitching moment in the tower bottom coordinate system based on the rotor thrust and the nacelle bending moment.

[0086] The wind turbine thrust reflects the harmful and adverse external loads that the wind turbine needs to bear during power generation, and the tower bottom pitching moment in the tower bottom coordinate system is a further reflection of the wind turbine thrust at the tower bottom. If the tower bottom bending and torsion are too large, it is easy to endanger the tower structure and reduce the operating life. Therefore, in order to identify the key loads of the whole machine, both the wind turbine thrust and the tower bottom pitching moment in the tower bottom coordinate system need to be measured. In the embodiments of the present application, the wind turbine thrust and the tower bottom pitching moment in the tower bottom coordinate system are calculated by the following formula:

[0087] First, determine the wind turbine thrust of the wind turbine by using the blade root flap moment; the calculation formula of the wind turbine thrust is: ; where a and b are the least square linearization coefficients obtained based on the blade root flap moment and the blade root thrust load simulation data, is the blade root flap moment;

[0088] Second, determine the tower bottom pitching moment in the tower bottom coordinate system based on the wind turbine thrust and the nacelle bending moment; the calculation formula of the tower bottom pitching moment is: ; is the drive train inclination angle, h is the tower height, is the nacelle bending moment component on the y-axis in the tower top coordinate system, is the nacelle weight; is the measured fore-aft acceleration of the nacelle, which is usually measured by an accelerometer used for tower top acceleration measurement. It reflects the influence of high-frequency nacelle inertial force on the tower life and needs to be added to the identification calculation.

[0089] It can be seen that after step S14, two key loads of the whole machine are measured and identified, which are the wind turbine thrust and the tower bottom pitching moment in the tower bottom coordinate system .

[0090] Step S15: Determine the target key loads of the wind turbine by using the blade root moment, the pitch mechanism moment, the hub center moment, the nacelle moment, the wind turbine thrust, and the tower bottom pitching moment, and when it is monitored that the target key loads trigger a pre-set load control strategy, control the whole machine of the wind turbine to enter an adjustment link to control the target key loads.

[0091] After the foregoing steps S11 to S14, a total of 22 key loads in 7 groups are obtained, and they are used as the target key loads that need to be measured for the whole wind turbine. In the embodiments of the present application, the target key loads identified by real-time measurement are combined with the set load thresholds to online control the key loads of the whole machine.

[0092] Specifically, the design values of the entire wind turbine corresponding to the target key loads are determined through simulation, and load thresholds for each load in the target key loads are set in the unit controller of the wind turbine according to the design values; when it is monitored that any one of the loads in the target key loads exceeds the load threshold, blade pitch-changing measures and power limitation measures are taken, and when it is monitored that the target key loads meet the preset exit conditions, the entire wind turbine is controlled to enter the normal operation stage.

[0093] It should be noted that in the embodiments of the present application, the unit controller controls the loads of the entire unit. Based on the design values of the key loads of the entire wind turbine obtained through simulation, the thresholds of each key load are set in the unit controller. In a feasible implementation, the threshold is preferably set to 75% - 90% of the design value. When any one of the measured and identified key loads exceeds the set threshold, blade pitch-changing and power limitation measures are taken, and the entire unit enters the load adjustment stage to control the load.

[0094] Meanwhile, during the process of controlling the load, it is monitored whether it can be adjusted back to the normal operation stage, that is, it is monitored whether the target key loads meet the preset exit conditions. In a feasible implementation, when the measured and identified key load drops below 60% of the design value for a period of time, usually set to 60 s, the load control and adjustment stage is exited, and the entire unit enters the normal operation stage.

[0095] As Figure 2 shown is an online intelligent control logic diagram of 22 key loads in 7 groups of the entire unit disclosed. After all the target key loads are respectively identified, the operation stage of the wind turbine is adjusted by determining whether the target key loads exceed the threshold.

[0096] The beneficial effects of the present application are as follows: By measuring the root bending moment of the blade, the bending moment of the pitch mechanism, the bending moment at the hub center, the bending moment of the nacelle, the wind turbine thrust, and the pitching moment at the tower base, the target key loads that the entire wind turbine needs to obtain are determined. The use of the target key loads can effectively identify and control the key load levels of the entire unit, which is beneficial to ensuring the safety of the tower structure of the wind turbine and improving the maintenance level.

[0097] Based on the above embodiments, in a feasible implementation, in order to be able to identify and manage the equivalent fatigue loads and remaining life of the key parts of the entire unit, in the embodiments of the present application, the rainflow counting method is used to process the cumulative measured and identified load time histories to obtain a series of load cycles, and each cycle has a corresponding load amplitude and load mean value . On this basis, the equivalent fatigue load of the key load can be calculated according to the following formula:

[0098] ;

[0099] In the formula, is the load amplitude is the number of cycles under, n is the number of intervals of the load amplitude, and m is the inverse slope of the material S-N curve.

[0100] The remaining life of the key part after the load time history is accumulated can be calculated by the following formula:

[0101] ;

[0102] In the formula, C is the material fatigue constant, is the total fatigue life.

[0103] Furthermore, according to the equivalent fatigue loads and remaining lives of the identified key components, corresponding management is carried out to formulate operation and maintenance measures. For the components with large equivalent fatigue loads and short remaining lives, appropriate protection is carried out, or the components are directly replaced to reduce the failure risk; for the components with small equivalent fatigue loads and long remaining lives, they can be fully utilized to increase the power generation of the unit.

[0104] Exemplarily, as Figure 3 shown is to verify the present invention through the operation case of the authoritative software Bladed for the overall load simulation of the wind turbine. The operation process includes:

[0105] Assume that the flap and pitch moments at the root of the three blades simulated by Bladed are the real-time measurement results of the fiber optic sensor or the cantilever sensor, and the pitch mechanism moment is obtained by combining the blade pitch angle;

[0106] Based on the identified pitch mechanism moment, the moment at the hub center in the rotating hub coordinate system is synthesized by combining the blade cone angle, where the hub torque is as Figure 4 shown, and the relative error between the simulation maximum value and the identified maximum value is -2.75%; based on the wind turbine azimuth angle, the moment at the hub center in the fixed hub coordinate system is obtained;

[0107] Combining the center of gravity and weight of the nacelle to obtain the nacelle moment in the tower top coordinate system, where the nacelle moment in the tower top coordinate system is as Figure 5 shown, and the relative error between the simulation maximum value and the identified maximum value is -6.72%;

[0108] Identifying the wind turbine thrust and the tower bottom pitch moment in the tower bottom coordinate system through the flap moment at the blade root, where the tower bottom pitch moment in the tower bottom coordinate system is as Figure 6 shown, and the relative error between the simulation maximum value and the identified maximum value is 5.56%;

[0109] Combining the key loads identified by real-time measurement with the set load threshold to online intelligently control 22 key loads in 7 groups of the overall machine, as Figure 2 shown;

[0110] Based on the cumulative measurements and the identified load time history, identify and manage the equivalent fatigue load and remaining life of the key parts of the whole machine.

[0111] Correspondingly, the embodiment of the present application also discloses a device for identifying and controlling the load of the whole machine. Refer to Figure 7 As shown, the device includes:

[0112] The first load identification module 11 is used to measure the root bending moment of the three blades of the wind turbine in real time, and determine the pitch mechanism bending moment based on the root bending moment and the real-time pitch angle of the three blades;

[0113] The second load identification module 12 is used to determine the blade cone angle and the wind turbine azimuth angle of the three blades, and determine the hub center bending moment in different hub coordinate systems based on the blade cone angle, the wind turbine azimuth angle and the pitch mechanism bending moment;

[0114] The third load identification module 13 is used to determine the center of gravity and weight of the nacelle of the wind turbine, and determine the nacelle bending moment in the tower top coordinate system based on the center of gravity of the nacelle, the weight of the nacelle and the hub center bending moment;

[0115] The fourth load identification module 14 is used to determine the wind turbine thrust of the wind turbine by using the root bending moment, and determine the tower bottom pitching moment in the tower bottom coordinate system based on the wind turbine thrust and the nacelle bending moment;

[0116] The load control module 15 is used to determine the target key load of the wind turbine by using the root bending moment, the pitch mechanism bending moment, the hub center bending moment, the nacelle bending moment, the wind turbine thrust and the tower bottom pitching moment, and when it is monitored that the target key load triggers a preset load control strategy, control the whole machine of the wind turbine to enter an adjustment link to control the target key load.

[0117] Among them, for the more specific working processes of the above-mentioned various modules, reference can be made to the corresponding content disclosed in the foregoing embodiments, and details will not be elaborated here.

[0118] It can be seen that through the above solution of this embodiment, it includes: measuring the root bending moments of the three blades of the wind turbine in real time, and determining the pitch mechanism bending moment based on the root bending moments and the real-time pitch angles of the three blades; determining the blade cone angles and the wind turbine azimuth angles of the three blades, and determining the hub center bending moment in different hub coordinate systems based on the blade cone angles, the wind turbine azimuth angles and the pitch mechanism bending moment; determining the nacelle center of gravity and the nacelle weight of the wind turbine, and determining the nacelle bending moment in the tower top coordinate system based on the nacelle center of gravity, the nacelle weight and the hub center bending moment; using the root bending moment to determine the wind turbine thrust, and determining the tower bottom pitching moment in the tower bottom coordinate system based on the wind turbine thrust and the nacelle bending moment; using the root bending moment, the pitch mechanism bending moment, the hub center bending moment, the nacelle bending moment, the wind turbine thrust and the tower bottom pitching moment to determine the target key loads of the wind turbine, and when it is monitored that the target key loads trigger a pre-set load control strategy, controlling the entire wind turbine to enter an adjustment link to control the target key loads.

[0119] The beneficial effects of this application are: by measuring the root bending moment, the pitch mechanism bending moment, the hub center bending moment, the nacelle bending moment, the wind turbine thrust and the tower bottom pitching moment, the target key loads that the entire wind turbine needs to obtain are determined. Using the target key loads can effectively identify and control the key load levels of the entire machine, which is beneficial to ensuring the safety of the wind turbine tower structure and improving the maintenance level.

[0120] Furthermore, the embodiment of this application also discloses an electronic device. Figure 8 It is a structural diagram of an electronic device 20 shown according to an exemplary embodiment. The content in the figure cannot be regarded as any limitation on the scope of use of this application.

[0121] Figure 8 It is a schematic structural diagram of an electronic device 20 provided by the embodiment of this application. The electronic device 20 may specifically include: at least one processor 21, at least one memory 22, a power supply 23, a communication interface 24, an input / output interface 25 and a communication bus 26. Among them, the memory 22 is used to store a computer program, and the computer program is loaded and executed by the processor 21 to implement the relevant steps in the method for identifying and controlling the loads of the entire machine disclosed in any of the foregoing embodiments. In addition, the electronic device 20 in this embodiment may specifically be a computer.

[0122] In this embodiment, the power supply 23 is used to provide operating voltages for the various hardware devices on the electronic device 20; the communication interface 24 can create a data transmission channel between the electronic device 20 and external devices, and the communication protocol it follows can be any communication protocol applicable to the technical solution of this application, and no specific limitation is imposed on it here; the input / output interface 25 is used to obtain external input data or output data to the outside, and its specific interface type can be selected according to specific application needs, and no specific limitation is imposed here.

[0123] In addition, the memory 22, as a carrier for resource storage, can be a read-only memory, a random access memory, a magnetic disk, an optical disk, etc. The resources stored thereon can include an operating system 221, a computer program 222, data 223, etc., and the data 223 can include various kinds of data. The storage method can be transient storage or permanent storage.

[0124] Among them, the operating system 221 is used to manage and control the various hardware devices and the computer program 222 on the electronic device 20, and it can be Windows Server, Netware, Unix, Linux, etc. In addition to the computer program that can be used to complete the identification and control method of the whole machine load executed by the electronic device 20 disclosed in any of the foregoing embodiments, the computer program 222 can further include computer programs that can be used to complete other specific tasks.

[0125] Furthermore, the embodiments of this application also disclose a computer-readable storage medium. The computer-readable storage medium mentioned here includes a random access memory (RAM), internal memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disks, magnetic disks, optical disks, or any other form of storage medium well-known in the technical field. Among them, when the computer program is executed by a processor, the foregoing identification and control method of the whole machine load is implemented. For the specific steps of this method, reference can be made to the corresponding content disclosed in the foregoing embodiments, and details will not be repeated here.

[0126] In this specification, the various embodiments are described in a progressive manner. Each embodiment focuses on the differences from other embodiments, and the same or similar parts among the various embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and reference can be made to the description of the method part for related parts.

[0127] The steps of the method or algorithm for identifying and controlling the overall machine load described in combination with the embodiments disclosed in this article can be implemented directly by hardware, software modules executed by a processor, or a combination of both. The software module can be placed in a random access memory (RAM), internal memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, register, hard disk, removable disk, CD-ROM, or any other form of storage medium well-known in the technical field.

[0128] Finally, it should also be noted that in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "including a..." does not exclude the existence of additional identical elements in the process, method, article or device including the said element.

[0129] The above has introduced in detail a method, device, equipment and medium for identifying and controlling the overall machine load provided by the present invention. Specific examples are used in this article to elaborate on the principle and implementation manner of the present invention. The description of the above embodiments is only used to help understand the method and its core idea of the present invention; at the same time, for those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific implementation manner and application scope. In summary, the content of this specification should not be construed as a limitation to the present invention.

Claims

1. A method for identifying and controlling the load of a whole machine, characterized in that: include: Measuring the blade root bending moment of three blades of the wind turbine in real time, and determining the pitch mechanism bending moment based on the blade root bending moment and the real-time pitch angles of the three blades; Determine the blade cone angles and the rotor azimuth angles of the three blades, and determine the hub center bending moments in different hub coordinate systems based on the blade cone angles, the rotor azimuth angles and the pitch mechanism bending moments; Determine the center of gravity and weight of the nacelle of the wind turbine generator set, and determine the nacelle bending moment in the tower top coordinate system based on the center of gravity of the nacelle, the nacelle weight and the hub center bending moment; Determine the rotor thrust of the wind turbine generator set by using the blade root bending moment, and determine the tower bottom pitching moment in a tower bottom coordinate system based on the rotor thrust and the nacelle bending moment; The target critical load of the wind turbine set is determined by utilizing the blade root bending moment, the pitch mechanism bending moment, the hub center bending moment, the nacelle bending moment, the rotor thrust and the tower bottom pitching moment. When it is detected that the target critical load triggers a preset load control strategy, the entire wind turbine set is controlled to enter an adjustment phase to control the target critical load.

2. The method for identifying and controlling the whole machine load according to claim 1, characterized in that: The real-time measurement of the blade root bending moment of the three blades of the wind turbine generator set and the determination of the pitch mechanism bending moment based on the blade root bending moment and the real-time pitch angle of the three blades include: The blade root flapping moment and blade root shimmy bending moment of the three blades of the wind turbine are measured in real time by using optical fiber sensors or cantilever sensors; Based on the blade root flapping bending moment, the blade root shimmy bending moment and the real-time pitch angles of the three blades, respectively determine the in-plane bending moment and out-of-plane bending moment of the pitch mechanism; The calculation formulas for the in-plane bending moment and the out-of-plane bending moment are: ； is the in-plane bending moment, is the out-of-plane bending moment; is the blade root shimmying bending moment, Swing the bending moment for the blade root; is the real-time pitch angle of the three blades; Characterize the three blades of a wind turbine.

3. The method for identifying and controlling the whole machine load according to claim 1, characterized in that: The determining of the blade cone angles and the rotor azimuth angles of the three blades, and determining the hub center bending moments in different hub coordinate systems based on the blade cone angles, the rotor azimuth angles and the pitch mechanism bending moments, includes: Determining blade cone angles of the three blades, and determining a first hub center bending moment in a rotating hub coordinate system based on the pitch mechanism bending moment; Determine the rotor azimuth angle of the three blades, and determine the second hub center bending moment in a fixed hub coordinate system based on the rotor azimuth angle and the first hub center bending moment; The calculation formula of the first hub center bending moment is: ； , , are the first hub center bending moment components on the x-axis, y-axis and z-axis in the rotating hub coordinate system respectively; , are the in-plane bending moment and out-of-plane bending moment of the pitch mechanism, Characterize the three blades of the wind turbine; is the blade cone angle of the three blades; The calculation formula of the second hub center bending moment is: ； , , are the components of the second hub center bending moment on the x-axis, y-axis and z-axis in the fixed hub coordinate system respectively; is the wind rotor azimuth, defined as the orientation angle of the first blade.

4. The method for identifying and controlling the whole machine load according to claim 1, characterized in that: The calculation formula of the cabin bending moment in the tower top coordinate system is: ； in, , , are the cabin bending moment components on the x-axis, y-axis and z-axis in the tower top coordinate system respectively; , , is the hub center bending moment in the fixed hub coordinate system; is the transmission chain inclination angle; is the weight of the cabin, is the center of gravity of the cabin, g is the acceleration due to gravity, is the wind wheel weight, is the wind wheel thrust, is the front-to-back distance between the hub center and the tower top center, It is the vertical distance between the hub center and the tower top center.

5. The method for identifying and controlling the whole machine load according to claim 2, characterized in that: The method of determining the rotor thrust of the wind turbine set by using the blade root bending moment, and determining the tower bottom pitching moment in the tower bottom coordinate system based on the rotor thrust and the nacelle bending moment, includes: The blade root flapping moment is used to determine the rotor thrust of the wind turbine set; the calculation formula of the rotor thrust is: ; where a and b are the least square linearization coefficients obtained based on the simulation data of blade root flapping moment and blade root thrust load, Swing the bending moment for the blade root; The tower bottom pitching moment in the tower bottom coordinate system is determined based on the wind rotor thrust and the nacelle bending moment; the calculation formula of the tower bottom pitching moment is: ; is the transmission chain inclination angle, h is the tower height, is the cabin bending moment component on the y-axis in the tower top coordinate system, is the weight of the cabin, is the measured cabin fore and aft acceleration.

6. The method for identifying and controlling the whole machine load according to claim 1, characterized in that: When it is detected that the target critical load triggers a preset load control strategy, the wind turbine generator set is controlled to enter an adjustment phase to control the target critical load, including: Determine the design value of the whole wind turbine set corresponding to the target critical load through simulation, and set the load threshold of each load in the target critical load in the unit controller of the wind turbine set according to the design value; When it is monitored that any of the target critical loads exceeds the load threshold, blade pitch changing measures and power limiting measures are taken, and when it is monitored that the target critical load meets the preset exit condition, the wind turbine set is controlled to enter the normal operation phase.

7. The method for identifying and controlling the whole machine load according to any one of claims 1 to 6, characterized in that: After the wind turbine generator set is controlled to enter the adjustment phase to control the target critical load, the method further includes: Processing the load time history of the target critical load by a rain flow counting method to determine the equivalent fatigue load and the remaining life of the target component in the whole machine of the wind turbine generator set; Formulate corresponding operation and maintenance measures for the target component according to the equivalent fatigue load and the remaining life; Wherein, the calculation formula of the equivalent fatigue load is: ; is the load amplitude The number of cycles under the load amplitude is n, and m is the inverse slope of the material SN curve. The calculation formula of the remaining life is: ; C is the material fatigue constant, is the total fatigue life.

8. A device for identifying and controlling the load of a whole machine, characterized in that: include: A first load identification module is used to measure the blade root bending moment of the three blades of the wind turbine in real time, and determine the bending moment of the pitch mechanism based on the blade root bending moment and the real-time pitch angle of the three blades; a second load identification module, configured to determine the blade cone angles and the rotor azimuth angles of the three blades, and determine the hub center bending moments in different hub coordinate systems based on the blade cone angles, the rotor azimuth angles and the pitch mechanism bending moments; A third load identification module is used to determine the center of gravity and weight of the nacelle of the wind turbine generator set, and determine the nacelle bending moment in the tower top coordinate system based on the center of gravity of the nacelle, the nacelle weight and the hub center bending moment; a fourth load identification module, configured to determine a rotor thrust of the wind turbine generator set by using the blade root bending moment, and determine a tower bottom pitching moment in a tower bottom coordinate system based on the rotor thrust and the nacelle bending moment; The load control module is used to determine the target critical load of the wind turbine set by using the blade root bending moment, the pitch mechanism bending moment, the hub center bending moment, the nacelle bending moment, the wind rotor thrust and the tower bottom pitching moment, and when it is monitored that the target critical load triggers a preset load control strategy, control the entire wind turbine set to enter an adjustment phase to control the target critical load.

9. An electronic device, characterized in that: The electronic device includes a processor and a memory; wherein the memory is used to store a computer program, and the computer program is loaded and executed by the processor to implement the method for identifying and controlling the whole machine load as described in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that: Used to store computer programs; wherein the computer program, when executed by a processor, implements the method for identifying and controlling the whole machine load as described in any one of claims 1 to 7.

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