Dynamic load evaluation method and system for yaw system of wind turbine

Abstract

The present invention discloses a method and system for evaluating the dynamic load of a yaw system of a wind turbine, which relates to the field of wind power technology and is used to solve the problem of realizing dynamic load evaluation of a yaw system of a wind turbine. The method comprises: establishing a dynamic simulation model of a wind turbine, the dynamic simulation model comprises a main engine, a yaw drive system and a yaw brake system of the wind turbine, simulating the operation of the wind turbine using the dynamic simulation model, causing the wind turbine to perform a yaw action at a preset time point during operation, obtaining a yaw drive load sequence and an external load sequence, the yaw drive load sequence is formed by arranging the load applied by the main engine to the yaw drive system with the operation time, the external load sequence is formed by arranging the external load received by the yaw system with the operation time, and obtaining the load evaluation result of the yaw system of the wind turbine according to the yaw drive load sequence and the external load sequence. The present invention realizes dynamic load evaluation of the yaw system of a wind turbine based on dynamic simulation.

Description

Technical Field

[0001] The present invention relates to the field of wind power technology, and in particular to a method and system for evaluating the dynamic load of a yaw system of a wind turbine generator set. Background Art

[0002] The yaw system of a wind turbine is simultaneously subjected to unstable aerodynamic external loads, yaw drive torque, yaw brake torque and other loads, and the frequent switching between the start and brake states will produce significant collisions and impacts, causing system vibrations and even possible damage to components. With the development trend of large-scale, high-power and lightweight wind turbines, the dynamic load effect of the yaw system has become increasingly prominent.

[0003] Therefore, in order to reduce the impact of the dynamic load effect of the yaw system on the wind turbine, optimize the performance of the wind turbine and optimize the control of the wind turbine, it is crucial to perform dynamic load analysis and evaluation on the yaw system of the wind turbine. Summary of the invention

[0004] The object of the present invention is to provide a method and system for evaluating the dynamic load of a yaw system of a wind turbine generator set, so as to realize the dynamic load evaluation of the yaw system of a wind turbine generator set based on dynamic simulation.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] A method for evaluating dynamic load of a yaw system of a wind turbine generator system, comprising:

[0007] Establishing a dynamic simulation model of a wind turbine generator set, wherein the dynamic simulation model includes a main engine of the wind turbine generator set, a yaw drive system of the wind turbine generator set, and a yaw brake system of the wind turbine generator set;

[0008] The operation of the wind turbine is simulated by using the dynamic simulation model. During the operation of the wind turbine, the wind turbine is made to perform a yaw action at a preset time point to obtain a yaw drive load time sequence and an external load time sequence. The yaw drive load time sequence is formed by arranging the load applied by the main engine of the wind turbine to the yaw drive system of the wind turbine with the operation time, and the external load time sequence is formed by arranging the external load applied to the yaw system of the wind turbine with the operation time;

[0009] A load evaluation result of the yaw system of the wind turbine generator system is obtained according to the yaw drive load time sequence and the external load time sequence.

[0010] In some embodiments, causing the wind turbine to perform a yaw action includes: causing the wind turbine to perform a yaw start process, be in a yaw state, and perform a yaw braking process;

[0011] Wherein, during the yaw start-up process, the main engine of the wind turbine generator set applies a load to the yaw drive system, the yaw brake system applies a braking force to the main engine of the wind turbine generator set, the braking force is reduced, and the yaw drive system applies a driving force to the main engine of the wind turbine generator set, so that the wind turbine generator set enters a yaw state;

[0012] When in the yaw state, the main engine of the wind turbine generator set applies a load to the yaw drive system, and the yaw drive system applies a driving force to the main engine of the wind turbine generator set;

[0013] During the yaw braking process, the yaw braking system applies a braking force to the main engine of the wind turbine generator set, the braking force increases, and the main engine of the wind turbine generator set applies a load to the yaw drive system.

[0014] In some embodiments, multiple preset time points are selected during the operation of the wind turbine generator set, and corresponding to any of the preset time points, the corresponding yaw drive load timing and the external load timing are obtained, so that multiple preset time points correspond to the multiple groups of external load timings obtained. For the yaw startup process, the external load at the beginning moment when the yaw drive system applies the driving force to the main engine of the wind turbine generator set is uniformly distributed in the range from the negative limit external load to the positive limit external load, or / and, for the average value of the external load in the yaw state, it is uniformly distributed in the range from the negative limit external load to the positive limit external load, or / and, for the yaw braking process, the external load at the moment when the yaw drive system stops applying the driving force to the main engine of the wind turbine generator set is uniformly distributed in the range from the negative limit external load to the positive limit external load.

[0015] In some implementations, obtaining a load evaluation result of a yaw system of the wind turbine generator system according to the yaw drive load time sequence and the external load time sequence includes:

[0016] According to the yaw drive load time sequence and the external load time sequence, a dynamic load coefficient is obtained, wherein the dynamic load coefficient represents the ratio of the yaw drive load to the external load at the same time point;

[0017] With the external load as the abscissa and the dynamic load coefficient as the ordinate, a scatter plot is drawn and an envelope curve of the scatter plot is obtained, and a load evaluation result of the yaw system of the wind turbine generator set is obtained according to the scatter plot and the envelope curve.

[0018] In some implementations, obtaining a load assessment result of the yaw system of the wind turbine generator set according to the scatter plot and the envelope curve includes:

[0019] According to the maximum external load and the relationship corresponding to the envelope curve, the yaw drive load corresponding to the maximum external load is obtained as the yaw limit load, so as to use the yaw limit load to perform ultimate strength verification on the yaw system of the wind turbine generator set.

[0020] In some embodiments, obtaining a load evaluation result of a yaw system of the wind turbine generator system according to the yaw drive load time sequence and the external load time sequence includes:

[0021] According to the external load time history of the yaw system, an external load spectrum of the yaw system and a mean value and an amplitude of the external load spectrum are obtained;

[0022] According to the mean value of the external load spectrum and the relationship corresponding to the envelope curve, the mean value of the load spectrum is obtained, the load spectrum is corrected for the mean value, and the fatigue strength of the yaw system of the wind turbine generator set is checked by using the mean value of the corrected load spectrum;

[0023] The amplitude of the load spectrum is obtained according to the amplitude of the external load spectrum and the relationship corresponding to the envelope curve, the amplitude of the load spectrum is corrected, and the fatigue strength of the yaw system of the wind turbine is checked with the amplitude of the corrected load spectrum.

[0024] In some implementations, selecting the preset time point includes:

[0025] The operation of the wind turbine set is simulated by using the dynamic simulation model of the wind turbine set to obtain the external load timing in a non-yaw state, and the preset time point is selected during the operation of the wind turbine set according to the external load timing in a non-yaw state.

[0026] In some embodiments, according to the external load timing in the non-yaw state, selecting the preset time point during the operation of the wind turbine generator set includes:

[0027] In the external load time series in the non-yaw state, general loads and special loads are screened, and multiple target loads are determined according to the screened general loads and special loads, so that the multiple target loads are evenly distributed in the range from the negative limit external load to the positive limit external load, and the time point corresponding to the target load is used as the preset time point. The general load refers to the external load whose load value is in the normal range, and the special load refers to the external load that belongs to the extreme case and needs attention.

[0028] A wind turbine yaw system dynamic load assessment system, comprising:

[0029] Memory for storing computer programs;

[0030] A processor is used to implement the steps of the method for evaluating the dynamic load of the yaw system of a wind turbine as described in any one of the above items when executing the computer program.

[0031] It can be known from the above technical scheme that the method and system for evaluating the dynamic load of the yaw system of a wind turbine provided by the present invention include: establishing a dynamic simulation model of the wind turbine, the dynamic simulation model includes the main engine of the wind turbine, the yaw drive system of the wind turbine and the yaw brake system of the wind turbine, using the dynamic simulation model to simulate the operation of the wind turbine, and in the operation of the wind turbine, at a preset time point, the wind turbine is made to perform a yaw action, and the yaw drive load timing and the external load timing are obtained. The yaw drive load timing is formed by the load applied by the main engine of the wind turbine to the yaw drive system of the wind turbine arranged with the running time, and the external load timing is formed by the external load received by the yaw system of the wind turbine arranged with the running time. Further, according to the yaw drive load timing and the external load timing, the load evaluation result of the yaw system of the wind turbine is obtained. The method and system for evaluating the dynamic load of the yaw system of a wind turbine of the present invention are based on dynamic simulation to realize the dynamic load evaluation of the yaw system of the wind turbine. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0033] Figure 1 A flow chart of a method for evaluating dynamic loads of a yaw system of a wind turbine provided by an embodiment of the present invention;

[0034] Figure 2 1 is a scatter plot and an envelope curve obtained in one embodiment of the present invention. DETAILED DESCRIPTION

[0035] In order to enable those skilled in the art to better understand the technical solutions in the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0036] For reference Figure 1 , Figure 1A flow chart of a method for evaluating the dynamic load of a yaw system of a wind turbine provided by an embodiment. As shown in the figure, the method for evaluating the dynamic load of a yaw system of a wind turbine includes the following steps:

[0037] S11: establishing a dynamics simulation model of a wind turbine generator set, wherein the dynamics simulation model includes a main engine of the wind turbine generator set, a yaw drive system of the wind turbine generator set, and a yaw brake system of the wind turbine generator set.

[0038] According to the structure of the wind turbine, the forces between the various structural parts and the movement of the various structural parts, a dynamic simulation model of the wind turbine is established.

[0039] The wind turbine generator set includes a main engine, a yaw drive system and a yaw brake system. Accordingly, the established dynamic simulation model includes the main engine of the wind turbine generator set, the yaw drive system of the wind turbine generator set and the yaw brake system of the wind turbine generator set.

[0040] S12: Utilizing the dynamic simulation model to simulate the operation of the wind turbine set, during the operation of the wind turbine set, the wind turbine set is caused to perform a yaw action at a preset time point, and a yaw drive load timing sequence and an external load timing sequence are obtained. The yaw drive load timing sequence is formed by arranging the load applied by the main engine of the wind turbine set to the yaw drive system of the wind turbine set with the operating time, and the external load timing sequence is formed by arranging the external load borne by the yaw system of the wind turbine set with the operating time.

[0041] The yaw drive load refers to the load applied by the main engine of the wind turbine to the yaw drive system of the wind turbine. The external load of the yaw system of the wind turbine refers to the external load on the yaw system of the wind turbine.

[0042] S13: Obtaining a load evaluation result of the yaw system of the wind turbine generator system according to the yaw drive load timing sequence and the external load timing sequence.

[0043] The method for dynamic load assessment of the yaw system of a wind turbine in this embodiment establishes a dynamic simulation model of the wind turbine, uses the dynamic simulation model to simulate the operation of the wind turbine, causes the wind turbine to perform a yaw action at a preset time point during operation, and obtains the yaw drive load timing and the external load timing to obtain the load assessment result of the yaw system of the wind turbine. This embodiment realizes dynamic load assessment of the yaw system of the wind turbine based on dynamic simulation.

[0044] In some embodiments, the main engine dynamics model of the wind turbine includes but is not limited to blades, towers, hubs or main drive chains. The yaw drive system dynamics model of the wind turbine includes but is not limited to yaw motors, output torque controllers or yaw reducers. The yaw brake system dynamics model of the wind turbine includes but is not limited to brake discs, brakes or hydraulic controllers.

[0045] In some embodiments, establishing a main engine dynamics model for a wind turbine includes but is not limited to simulating using a multi-body dynamics module, aerodynamic elements, and a main control force element of the wind turbine. The yaw drive system includes but is not limited to simulating using a multi-body dynamics module and a state-following dynamic element. The yaw brake system includes but is not limited to simulating using a multi-body dynamics module and a nonlinear friction force element. In some embodiments, a dynamics simulation model of a wind turbine can be established based on a dynamics equation. In some embodiments, a modeling software can be used to establish a dynamics simulation model of a wind turbine, and SIMPACK software can be used but is not limited to.

[0046] The yaw drive load refers to the load applied by the main engine of the wind turbine generator set to the yaw drive system of the wind turbine generator set, and specifically may be the reaction force transmitted by the main engine of the wind turbine generator set to the yaw drive system of the wind turbine generator set.

[0047] The external load of the yaw system of a wind turbine refers to the external load on the yaw system of the wind turbine during the operation of the wind turbine. The external load comes from the wind load and is transmitted to the yaw system in six directions, including the thrust Fx along the x-axis, the thrust Fy along the y-axis, the thrust Fz along the z-axis, the rotational force Mx around the x-axis, the rotational force My around the y-axis, and the rotational force Mz around the z-axis. In some embodiments, the external load of the yaw system of a wind turbine may be any one or more of the six loads transmitted to the yaw system.

[0048] In some embodiments, causing the wind turbine to perform a yaw action includes: causing the wind turbine to perform a yaw start process, be in a yaw state, and perform a yaw braking process;

[0049] Wherein, during the yaw start-up process, the main engine of the wind turbine generator set applies a load to the yaw drive system, the yaw brake system applies a braking force to the main engine of the wind turbine generator set, the braking force is reduced, and the yaw drive system applies a driving force to the main engine of the wind turbine generator set, so that the wind turbine generator set enters a yaw state;

[0050] When in the yaw state, the main engine of the wind turbine generator set applies a load to the yaw drive system, and the yaw drive system applies a driving force to the main engine of the wind turbine generator set;

[0051] During the yaw braking process, the yaw braking system applies a braking force to the main engine of the wind turbine generator set, the braking force increases, and the main engine of the wind turbine generator set applies a load to the yaw drive system.

[0052] During the yaw start-up process, the yaw brake system applies braking force to the main engine of the wind turbine, which can be the yaw brake system transmitting braking torque to the main engine. The hydraulic controller is set to the pressure relief mode, the braking torque is reduced, and the braking force is reduced. The yaw drive system applies driving force to the main engine of the wind turbine to put the wind turbine into the yaw state, which can be the yaw motor output torque activation, and the yaw drive system transmits torque to the main engine as a driving force to put the wind turbine into the yaw state.

[0053] In the yaw state, the braking force is reduced to the set value, and the hydraulic controller no longer works. The main engine of the wind turbine applies a load to the yaw drive system, that is, the main engine transmits a reaction force to the yaw drive system as a yaw drive load. The yaw drive system applies a driving force to the main engine of the wind turbine, which can be the yaw drive system transmitting a driving torque to the main engine.

[0054] During the yaw braking process, the yaw braking system applies braking force to the main engine of the wind turbine, and the hydraulic controller is set to the pressure-building mode, and the braking force increases. The yaw drive system stops applying driving force to the main engine of the wind turbine, which can be the yaw motor output torque off. The main engine of the wind turbine applies a load to the yaw drive system, that is, the main engine transmits a reaction force to the yaw drive system as a yaw drive load.

[0055] In some embodiments, during the operation of the wind turbine, multiple preset time points are selected, and corresponding to any of the preset time points, the corresponding yaw drive load timing and the external load timing are obtained, so that the multiple preset time points correspond to the multiple sets of external load timings obtained, and for the yaw start-up process, the external load at the beginning of the yaw drive system applying the driving force to the main engine of the wind turbine is uniformly distributed within the range of the negative limit external load to the positive limit external load. The multiple sets of external load timings obtained, for the yaw start-up process, the external load at the beginning of the yaw drive system applying the driving force to the main engine of the wind turbine is uniformly distributed within the range of the negative limit external load to the positive limit external load, so that the obtained yaw drive load timing and external load timing data can be made more representative and universal, which is helpful for more accurate dynamic load evaluation of the yaw system of the wind turbine, and improves the accuracy of the load evaluation results of the yaw system of the wind turbine.

[0056] In some embodiments, during the operation of the wind turbine, multiple preset time points are selected, and corresponding to any of the preset time points, the corresponding yaw drive load timing and the external load timing are obtained, so that the multiple sets of external load timings obtained corresponding to the multiple preset time points are uniformly distributed in the range from the negative limit external load to the positive limit external load for the average value of the external load in the yaw state. The obtained yaw drive load timing and external load timing data can be made more representative and universal, which is helpful for more accurate dynamic load evaluation of the yaw system of the wind turbine, and improves the accuracy of the load evaluation results of the yaw system of the wind turbine.

[0057] In some embodiments, during the operation of the wind turbine, multiple preset time points are selected, and corresponding to any of the preset time points, the corresponding yaw drive load timing and the external load timing are obtained, so that multiple preset time points correspond to multiple sets of external load timings obtained. For the yaw braking process, the external load at the moment when the yaw drive system stops applying driving force to the main engine of the wind turbine is uniformly distributed within the range of negative limit external load to positive limit external load. The obtained yaw drive load timing and external load timing data can be made more representative and universal, which helps to more accurately evaluate the dynamic load of the yaw system of the wind turbine and improve the accuracy of the load evaluation results of the yaw system of the wind turbine.

[0058] In some embodiments, during the operation of the wind turbine, multiple preset time points are selected, and corresponding to any of the preset time points, the corresponding yaw drive load timing and the external load timing are obtained, so that multiple preset time points correspond to multiple sets of external load timings obtained, and for the yaw start-up process, the external load at the time when the yaw drive system starts to apply the driving force to the main engine of the wind turbine is uniformly distributed within the range of the negative limit external load to the positive limit external load, and the external load average value in the yaw state is uniformly distributed within the range of the negative limit external load to the positive limit external load, and for the yaw braking process, the external load at the time when the yaw drive system stops applying the driving force to the main engine of the wind turbine is uniformly distributed within the range of the negative limit external load to the positive limit external load. The obtained yaw drive load timing and external load timing data can be made more representative and universal, which is helpful for more accurate dynamic load evaluation of the yaw system of the wind turbine, and improves the accuracy of the load evaluation results of the yaw system of the wind turbine.

[0059] The negative limit external load refers to the maximum negative value of the external load borne by the yaw system of the wind turbine, and the positive limit external load refers to the maximum positive value of the external load borne by the yaw system of the wind turbine.

[0060] If the yaw drive system applies driving force to the main engine through the yaw motor output torque, during the yaw startup process, the time when the yaw drive system starts applying driving force to the main engine of the wind turbine can be the yaw motor output torque activation time. During the yaw braking process, the time when the yaw drive system stops applying driving force to the main engine of the wind turbine can be the yaw motor output torque shutdown time.

[0061] In some embodiments, selecting the preset time point includes: simulating the operation of the wind turbine group using the dynamic simulation model of the wind turbine group to obtain the external load timing in a non-yaw state, and selecting the preset time point during the operation of the wind turbine group according to the external load timing in the non-yaw state.

[0062] In the non-yaw state, the yaw drive system does not work and does not apply driving force to the main engine of the wind turbine. The yaw brake system applies the maximum braking force to the main engine of the wind turbine. The yaw motor output torque can be turned off, the hydraulic brake is set to full pressure, and the yaw brake system transmits the maximum braking torque to the main engine as friction resistance.

[0063] In some embodiments, according to the external load sequence in the non-yaw state, selecting the preset time point during the operation of the wind turbine generator set includes: in the external load sequence in the non-yaw state, screening general loads and special loads, determining multiple target loads according to the screened general loads and special loads, so that the multiple target loads are evenly distributed within the range of negative limit external load to positive limit external load, and the time point corresponding to the target load is used as the preset time point, the general load refers to the external load whose load value is in the normal range, and the special load refers to the external load that belongs to the extreme case and needs attention. Special loads may include the limit load of the wind turbine generator set or a load sequence containing severe positive and negative fluctuations.

[0064] For example, according to the external load sequence in the non-yaw state, according to the general load and special load, the range of the negative limit external load to the positive limit external load is -6000 to +6000, then multiple uniformly distributed load values ​​are selected within the range of -6000 to +6000, that is, multiple target loads are selected, and the time point corresponding to each target load is used as a preset time point. For example, the time points corresponding to the loads of -6000, -3000, 0, +3000, and +6000 are selected within the range of -6000 to +6000.

[0065] In some implementations, obtaining a load evaluation result of the yaw system of the wind turbine generator system according to the yaw drive load time sequence and the external load time sequence includes:

[0066] S131: obtaining a dynamic load coefficient according to the yaw drive load time sequence and the external load time sequence, wherein the dynamic load coefficient represents a ratio of the yaw drive load to the external load at the same time point;

[0067] S132: Drawing a scatter plot with the external load as the horizontal coordinate and the dynamic load coefficient as the vertical coordinate and obtaining an envelope curve of the scatter plot, and obtaining a load evaluation result of the yaw system of the wind turbine generator set according to the scatter plot and the envelope curve.

[0068] According to the obtained yaw drive load time sequence and external load time sequence, the ratio of the yaw drive load to the external load at the same time point is calculated to obtain the dynamic load coefficient. The dynamic load coefficient corresponding to different external loads is obtained, and further data points are plotted in the coordinate system according to different external loads and the corresponding dynamic load coefficients to draw a scatter plot.

[0069] The envelope curve of the scatter plot can be obtained by fitting the scatter plot. In some embodiments, an iterative trial and error method can be used to first assume the form and parameters of the curve equation of the envelope curve, and perform multiple iterative operations based on each data point so that the obtained envelope curve can envelop the scatter points, thereby obtaining the equation of the envelope curve. In some embodiments, the equation of the envelope curve is expressed as:

[0070] K d = f ( M );

[0071] in, K d represents the dynamic load coefficient, M represents the external load of the yaw system, the function f It can be determined by fitting the scattered data. Figure 2 , Figure 2 is a scatter plot and envelope curve obtained in one embodiment, Figure 2 The middle horizontal axis represents the yaw external load, which is the external load of the yaw system.

[0072] In some embodiments, obtaining the load assessment result of the yaw system of the wind turbine according to the scatter plot and the envelope curve includes: obtaining the yaw drive load corresponding to the maximum external load as the yaw limit load according to the maximum external load and the relationship corresponding to the envelope curve, so as to use the yaw limit load to perform an ultimate strength check on the yaw system of the wind turbine. The relationship corresponding to the envelope curve refers to the equation of the envelope curve, which describes the relationship between the dynamic load coefficient and the external load. The maximum external load refers to the maximum external load of the yaw system of the wind turbine set when designing the wind turbine.

[0073] In the calculation of the yaw system limit load, the following formula can be used:

[0074] M dmax = K d0 · M max = f ( M max ) M max ;

[0075] in, M dmax It represents the limit load of the yaw system, namely the yaw limit load. M max represents the maximum external load, K d0 Indicates the dynamic load factor corresponding to the maximum external load. M dmax As the ultimate load, the ultimate strength of the yaw system is checked.

[0076] In some embodiments, obtaining a load evaluation result of a yaw system of the wind turbine generator system according to the yaw drive load time sequence and the external load time sequence includes:

[0077] According to the external load time history of the yaw system, an external load spectrum of the yaw system and a mean value and an amplitude of the external load spectrum are obtained;

[0078] According to the mean value of the external load spectrum and the relationship corresponding to the envelope curve, the mean value of the load spectrum is obtained, the load spectrum is corrected for the mean value, and the fatigue strength of the yaw system of the wind turbine generator set is checked with the mean value of the corrected load spectrum;

[0079] The amplitude of the load spectrum is obtained according to the amplitude of the external load spectrum and the relationship corresponding to the envelope curve, the amplitude of the load spectrum is corrected, and the fatigue strength of the yaw system of the wind turbine is checked with the amplitude of the corrected load spectrum.

[0080] The external load spectrum refers to the spectrum of the external load. The load spectrum refers to the spectrum of the yaw drive load. The relationship corresponding to the envelope curve refers to the equation of the envelope curve, which describes the relationship between the dynamic load coefficient represented by the envelope curve and the external load.

[0081] In some embodiments, in the calculation of the fatigue load of the yaw system, the rain flow counting method can be used to obtain the external load spectrum of the yaw system according to the external load time history of the yaw system (i.e., the external load time series). In some embodiments, the external load time history of the yaw system can be calculated by GH Bladed software.

[0082] In some implementations, the following formula may be used to perform mean correction on the load spectrum:

[0083] M dmeani = K di · M meani = f ( M meani ) M meani ;

[0084] in, M dmeani is the load spectrum of the yaw system i Mean value, M meani is the external load spectrum of the yaw system i Mean value, K di is the external load spectrum of the yaw system i The dynamic load coefficient corresponding to the mean value.

[0085] In some implementations, the following formula may be used to perform amplitude correction on the load spectrum:

[0086] M drangeij = K di · M rangeij = f ( M meani ) M rangeij ;

[0087] in, M drangeij is the load spectrum of the yaw system i The mean value corresponds to j Amplitude, M rangeij is the external load spectrum of the yaw system i The mean value corresponds to j Amplitude, K di is the external load spectrum of the yaw system i The dynamic load coefficient corresponding to the mean value.

[0088] Can M dmeani As the load spectrum mean, M drangeij As the load spectrum amplitude, the fatigue strength of the yaw system is checked.

[0089] This embodiment also provides a wind turbine yaw system dynamic load assessment system, including:

[0090] Memory for storing computer programs;

[0091] A processor is used to implement the steps of the method for evaluating the dynamic load of the yaw system of a wind turbine set as described in any one of the above embodiments when executing the computer program.

[0092] The dynamic load assessment system for the yaw system of a wind turbine in this embodiment establishes a dynamic simulation model of the wind turbine, uses the dynamic simulation model to simulate the operation of the wind turbine, causes the wind turbine to perform a yaw action at a preset time point during operation, and obtains the yaw drive load timing and the external load timing to obtain the load assessment result of the yaw system of the wind turbine. This embodiment realizes dynamic load assessment of the yaw system of the wind turbine based on dynamic simulation.

[0093] The method and system for evaluating the dynamic load of the yaw system of a wind turbine of this embodiment have the following technical effects: based on dynamic simulation, a scatter plot and an envelope curve of the dynamic load coefficient of the yaw system under all working conditions are obtained, so that the dynamic load of the yaw system can be evaluated in a refined manner, and the accuracy and reliability of the yaw system load prediction can be improved. In addition, the provided calculation method is simple, has good versatility, and has high feasibility in engineering applications.

[0094] The above is a detailed introduction to the method and system for evaluating the dynamic load of the yaw system of a wind turbine provided by the present invention. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. It should be pointed out that for ordinary technicians in this technical field, without departing from the principles of the present invention, several improvements and modifications can be made to the present invention, and these improvements and modifications also fall within the scope of protection of the present invention.

Claims

1. A method for evaluating the dynamic load of a yaw system of a wind turbine, characterized in that: include: Establishing a dynamics simulation model of a wind turbine generator set, wherein the dynamics simulation model includes a main engine of the wind turbine generator set, a yaw drive system of the wind turbine generator set, and a yaw brake system of the wind turbine generator set; The operation of the wind turbine is simulated by using the dynamic simulation model. During the operation of the wind turbine, the wind turbine is made to perform a yaw action at a preset time point to obtain a yaw drive load time sequence and an external load time sequence. The yaw drive load time sequence is formed by arranging the load applied by the main engine of the wind turbine to the yaw drive system of the wind turbine with the operation time, and the external load time sequence is formed by arranging the external load applied to the yaw system of the wind turbine with the operation time; According to the yaw drive load timing and the external load timing, a load evaluation result of the yaw system of the wind turbine is obtained, including: according to the yaw drive load timing and the external load timing, a dynamic load coefficient is obtained, and the dynamic load coefficient represents the ratio of the yaw drive load to the external load at the same time point; with the external load as the abscissa and the dynamic load coefficient as the ordinate, a scatter plot is drawn and an envelope curve of the scatter plot is obtained, and the load evaluation result of the yaw system of the wind turbine is obtained according to the scatter plot and the envelope curve; Obtaining a load assessment result of the yaw system of the wind turbine according to the scatter plot and the envelope curve includes: obtaining a yaw drive load corresponding to the maximum external load as a yaw limit load according to a relationship between the maximum external load and the envelope curve, so as to perform an ultimate strength check on the yaw system of the wind turbine using the yaw limit load. The maximum external load refers to the maximum external load of the yaw system of the wind turbine set when designing the wind turbine.

2. The method for evaluating the dynamic load of the yaw system of a wind turbine according to claim 1, characterized in that: Making the wind turbine set perform a yaw action includes: making the wind turbine set perform a yaw start process, be in a yaw state, and perform a yaw braking process; Wherein, during the yaw start-up process, the main engine of the wind turbine generator set applies a load to the yaw drive system, the yaw brake system applies a braking force to the main engine of the wind turbine generator set, the braking force is reduced, and the yaw drive system applies a driving force to the main engine of the wind turbine generator set, so that the wind turbine generator set enters a yaw state; When in the yaw state, the main engine of the wind turbine generator set applies a load to the yaw drive system, and the yaw drive system applies a driving force to the main engine of the wind turbine generator set; During the yaw braking process, the yaw braking system applies a braking force to the main engine of the wind turbine generator set, the braking force increases, and the main engine of the wind turbine generator set applies a load to the yaw drive system.

3. The method for evaluating the dynamic load of the yaw system of a wind turbine according to claim 2, characterized in that: During the operation of the wind turbine generator set, multiple preset time points are selected, and corresponding to any of the preset time points, the corresponding yaw drive load timing and the external load timing are obtained, so that the multiple preset time points correspond to the multiple groups of external load timings obtained. For the yaw start-up process, the external load at the beginning moment when the yaw drive system applies the driving force to the main engine of the wind turbine generator set is uniformly distributed in the range from the negative limit external load to the positive limit external load, or / and, for the average value of the external load in the yaw state, it is uniformly distributed in the range from the negative limit external load to the positive limit external load, or / and, for the yaw braking process, the external load at the moment when the yaw drive system stops applying the driving force to the main engine of the wind turbine generator set is uniformly distributed in the range from the negative limit external load to the positive limit external load.

4. The method for evaluating the dynamic load of the yaw system of a wind turbine according to claim 1, characterized in that: Obtaining a load evaluation result of the yaw system of the wind turbine generator system according to the yaw drive load time sequence and the external load time sequence includes: According to the external load time history of the yaw system, an external load spectrum of the yaw system and a mean value and an amplitude of the external load spectrum are obtained; According to the mean value of the external load spectrum and the relationship corresponding to the envelope curve, the mean value of the load spectrum is obtained, the load spectrum is corrected for the mean value, and the fatigue strength of the yaw system of the wind turbine generator set is checked by using the mean value of the corrected load spectrum; The amplitude of the load spectrum is obtained according to the amplitude of the external load spectrum and the relationship corresponding to the envelope curve, the amplitude of the load spectrum is corrected, and the fatigue strength of the yaw system of the wind turbine is checked with the amplitude of the corrected load spectrum.

5. The method for evaluating the dynamic load of the yaw system of a wind turbine according to claim 1, characterized in that: Selecting the preset time point includes: The operation of the wind turbine set is simulated by using the dynamic simulation model of the wind turbine set to obtain the external load timing in a non-yaw state, and the preset time point is selected during the operation of the wind turbine set according to the external load timing in a non-yaw state.

6. The method for evaluating the dynamic load of the yaw system of a wind turbine according to claim 5, characterized in that: According to the external load timing in the non-yaw state, selecting the preset time point during the operation of the wind turbine generator set includes: In the external load time series in the non-yaw state, general loads and special loads are screened, and multiple target loads are determined according to the screened general loads and special loads, so that the multiple target loads are evenly distributed in the range from the negative limit external load to the positive limit external load, and the time point corresponding to the target load is used as the preset time point. The general load refers to the external load whose load value is in the normal range, and the special load refers to the external load that belongs to the extreme case and needs attention.

7. A wind turbine yaw system dynamic load assessment system, characterized in that: include: Memory for storing computer programs; A processor is used to implement the steps of the method for evaluating the dynamic load of the yaw system of a wind turbine set as claimed in any one of claims 1 to 6 when executing the computer program.

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