Tower fatigue load accumulation method and system based on wind direction frequency distribution

Abstract

The application discloses a tower fatigue load accumulation method and system based on wind direction frequency distribution, and the method comprises the following steps: S1, acquiring the wind frequency distribution of each sector of a specific site location, the Weibull distribution parameters of each sector and the effective turbulence intensity of each sector; S2, obtaining the equivalent fatigue load corresponding to the tower circumference weld hot spot through load calculation; S3, sorting the wind frequency distribution of each sector and the equivalent fatigue load corresponding to the tower circumference weld hot spot; according to the fatigue curve index m of the material and the sorted parameters, equivalent conversion is performed on the equivalent fatigue load of all sectors to obtain the equivalent maximum value of the tower circumference; and S4, according to the equivalent fatigue load-stress relationship, the equivalent maximum fatigue damage of the tower circumference life cycle is calculated. The application has the advantages of effectively reducing the equivalent fatigue load of the tower weld, reducing the weight of the tower, saving the amount of steel material, reducing the investment cost of the wind power and the like.

Description

TECHNICAL FIELD

[0001] The present application mainly relates to the field of wind power technology, and particularly relates to a tower fatigue load accumulation method and system based on wind direction frequency distribution. BACKGROUND

[0002] The tower of a wind turbine set bears an alternating fatigue load for 20 years of life, and the fatigue load mainly comes from turbulence. Due to the roughness of the ground and the influence of the wake, the turbulence intensity changes with the change of the wind direction. The traditional tower fatigue load calculation does not consider the influence of the wind direction on the tower fatigue load, and assumes that the wind direction is always along one direction for load calculation simulation. However, in a specific wind site, the operation of the wind turbine is based on the yaw of the main wind direction, so that the wind turbine is always in the optimal wind direction. Therefore, the fatigue accumulation of the tower by using the load in one direction is relatively conservative. SUMMARY

[0003] The technical problem to be solved by the present application is to provide an effective tower fatigue load accumulation method and system based on wind direction frequency distribution for reducing the equivalent fatigue load of the tower weld.

[0004] To solve the above technical problems, the technical solution provided by the present application is as follows:

[0005] A tower fatigue load accumulation method based on wind direction frequency distribution, comprising the following steps:

[0006] S1, obtaining the wind frequency distribution P(θ) of each sector of a specific site location, the Weibull distribution parameters (A, k) of each sector, and the effective turbulence intensity Ieff of each sector;

[0007] S2, obtaining the nacelle azimuth angle θ and the tower circumference weld hot spot P j corresponding to the equivalent fatigue load M pj (θ) through load calculation;

[0008] S3, sorting the wind frequency distribution P(θ) of each sector and the tower circumference weld hot spot P j corresponding to the equivalent fatigue load M pj (θ); according to the fatigue curve index m of the material and the sorted M pj (θ) and P(θ), equivalent conversion is performed on the equivalent fatigue loads of all sectors to obtain the equivalent maximum value DEL_Max of the tower circumference;

[0009] S4, according to the equivalent fatigue load-stress relationship, the maximum stress range and the cycle number of the tower circumference are calculated, and the equivalent maximum fatigue damage Dmax of the tower circumference life cycle is calculated.

[0010] Preferably, the specific process of step S2 is: according to the wind rose diagram, the n sectors are divided into equal parts, assuming that the wind direction of the unit is at the center of each sector, then the equivalent fatigue load M j of the P1, P2, … P j points on the tower circumference corresponding to the position of the wind direction is respectively solved. n pj

[0011] Preferably, in step S3, the equivalent fatigue load of the P1, P2, … P j … P n points on the tower circumference is accumulated according to the proportion of the wind direction of each sector in the wind rose diagram. j The equivalent conversion of the tower circumference weld hot spot P j is converted according to the following formula:

[0012]

[0013] Preferably, the n is between 10-20.

[0014] Preferably, in step S1, the micro-siting results of each site of the wind farm are obtained according to the fluid mechanics simulation, and the wind frequency distribution P(θ) of each sector, the Weibull distribution parameters (A, k) of each sector and the effective turbulence intensity Ieff of each sector of the specific site of the wind farm are obtained.

[0015] The application also discloses a tower fatigue load accumulation system based on wind direction frequency distribution, which comprises:

[0016] A first module is used to obtain the wind frequency distribution P(θ) of each sector, the Weibull distribution parameters (A, k) of each sector and the effective turbulence intensity Ieff of each sector of the specific site of the wind farm.

[0017] A second module is used to obtain the cabin azimuth angle θ and the equivalent fatigue load M j (θ) of the tower circumference weld hot spot P pj through load calculation.

[0018] A third module is used to sort the wind frequency distribution P(θ) of each sector and the equivalent fatigue load M j (θ) of the tower circumference weld hot spot P pj , and to perform equivalent conversion on the equivalent fatigue load of all sectors according to the fatigue curve index m of the material and the corresponding M pj (θ) and P(θ) after sorting, so as to obtain the equivalent maximum value DEL_Max of the tower circumference.

[0019] A fourth module is configured to calculate the maximum stress range and the number of cycles of the tower drum circumference according to an equivalent fatigue load-stress relationship, and to calculate the equivalent maximum fatigue damage Dmax of the tower drum circumference life cycle.

[0020] The application further discloses a computer readable storage medium, which stores a computer program, and the computer program performs the steps of the tower drum fatigue load accumulation method based on a wind direction frequency distribution when executed by a processor.

[0021] The application further discloses a computer device, which comprises a memory and a processor, and the memory stores a computer program, and the computer program performs the steps of the tower drum fatigue load accumulation method based on a wind direction frequency distribution when executed by the processor.

[0022] Compared with the prior art, the application has the following advantages:

[0023] The application divides the tower drum circumference weld fatigue hot spots according to a wind rose diagram, and can be divided into any equal parts (for example, 16 equal parts), and an equivalent fatigue load of the tower drum circumference weld hot spot corresponding to different cabin azimuth angles is obtained; the application sorts the equivalent fatigue load and the occurrence time probability of each sector according to the equivalent fatigue load of the tower drum circumference weld fatigue hot spot and the occurrence time probability of each sector, obtains the corresponding sequence of the optimized equivalent fatigue load and the occurrence time probability of each sector, and further obtains the equivalent maximum equivalent fatigue load of the tower drum circumference.

[0024] The application adopts the tower drum fatigue load accumulation based on a wind direction frequency distribution, can effectively reduce the equivalent fatigue load of the tower drum weld, thereby reducing the weight of the tower drum of the wind turbine generator set, saving the amount of steel material, reducing the weight of the tower drum of the wind turbine generator set, and thereby reducing the investment cost of the wind turbine generator set. The life prediction of the tower drum fatigue weld can master the fatigue life state of the tower drum as early as possible or in real time. The output state (power generation hours) and the remaining life of the wind turbine generator set at the site are not equal for the whole wind farm, and therefore the life at the site can be predicted, the output of the whole field unit can be controlled, for example, in the power limiting state, the units with low predicted life are preferentially shut down, so that the life and power generation of the whole field wind turbine generator set are optimized; the tower drum life is predicted as early as possible, and if it is found that the predicted life exceeds the design life, the sector management of the tower drum life can be performed to reduce the fatigue damage of the dangerous point Pj of the circumference. BRIEF DESCRIPTION OF DRAWINGS

[0025] Figure 1 The tower drum load coordinate system M in the application x , M y is a schematic diagram.

[0026] Figure 2 The flowchart of the method in the application in a specific embodiment.

[0027] Figure 3 The wind direction distribution diagram in the present application.

[0028] Figure 4 The tower drum circumferential P j Point equivalent fatigue load accumulation result diagram.

[0029] Figure 5 The flow chart of the method in the present application in specific application. DETAILED DESCRIPTION

[0030] The present application is further described below in conjunction with the accompanying drawings and specific embodiments.

[0031] As Figure 2 shown, the tower drum fatigue load accumulation method based on wind direction frequency distribution of the present embodiment includes the steps of:

[0032] S1, obtaining the wind frequency distribution P(θ) of each sector of a specific site location, the Weibull distribution parameters (A, k) of each sector, and the effective turbulence intensity Ieff of each sector;

[0033] S2, obtaining the nacelle azimuth angle θ and the tower drum circumferential weld hot spot P j corresponding equivalent fatigue load M pj (θ) through load calculation;

[0034] S3, sorting the wind frequency distribution P(θ) of each sector; sorting the tower drum circumferential weld hot spot P j corresponding equivalent fatigue load M pj (θ); according to the fatigue curve index m of the material and the sorted M pj (θ) and P(θ), equivalent conversion is performed on the equivalent fatigue loads of all sectors to obtain the equivalent maximum value DEL_Max of the tower drum circumferential;

[0035] S4, according to the equivalent fatigue load-stress relationship, the maximum stress range and the cycle number of the tower drum circumferential are calculated to obtain the equivalent maximum fatigue damage Dmax of the tower drum circumferential life cycle.

[0036] Specifically, in step S1, the micro-siting results of each location of the wind farm are obtained according to fluid mechanics simulation, and the wind frequency distribution P(θ) of each sector of a specific site location, the Weibull distribution parameters (A, k) of each sector, and the effective turbulence intensity Ieff of each sector are obtained.

[0037] In step S2, the tower drum circumferential weld hot spot P j point load conversion relationship and sector division method are as Figure 1As shown; the wind rose diagram is divided into 16 equal sectors. Assuming the unit's azimuth angle is at the center of each sector, the wind direction at point P is then calculated. j P1, P2, ... P on the circumference of the tower corresponding to the position j …P 16 The equivalent fatigue load M at the point pj (θ); Finally, based on the wind direction weighting of each sector in the wind rose diagram, P1, P2, ... P on the tower circumference are calculated. j …P 16 Accumulated equivalent fatigue load at points;

[0038] Among them, the tower circumference P j Point P3, in the prevailing wind direction, according to the IEC 61400-1 standard specification, the tower load coordinate system M x M y Show opinions Figure 1 As shown. Where P j Based on the wind rose diagram, the sectors are typically divided into 16 sectors, namely P1, P2, P3…P… j …P 16 M x : Tower bending moment (left and right); M y : Tower front and rear bending moments; M pj Point P in the circumferential direction j The projected bending moment; θ: the angle between the wind direction and the north direction of the tower; α: the angle at point P in the circumferential direction. j The angle with due north; according to Figure 1 M x The direction is consistent with the direction of the incoming wind speed, for point P on the circumference of the tower. j The bending moment is based on M x and M y Obtained through projection transformation. Coordinate system load M x Circumferential direction P j The included angle β between the points is obtained through angle conversion, as shown in the following formula:

[0039] β=π+θ-α (1)

[0040] β: Coordinate system load M x Circumferential direction P j The angle between the points.

[0041] For any point P on the circumference j The corresponding bending moment can be obtained through coordinate system projection transformation, and the transformation formula is as follows:

[0042] M pj (β)=M x cos(β)+M y sin(β) (2)

[0043] In step S3, the wind frequency distribution P(θ) of 16 sectors is sorted from large to small; the tower circumference weld hot spot P j The corresponding equivalent fatigue load M pj (θ) is sorted from large to small; according to the fatigue curve index m of the material and the corresponding M pj (θ) and P(θ) after sorting, the equivalent fatigue load of all sectors is converted by the formula to obtain the equivalent tower circumference maximum value DEL_Max; wherein the equivalent fatigue load of P1, P2, … P j …P 16 The point on the tower circumference weld is converted according to the following formula: j

[0044]

[0045] Finally, in step S4, according to the equivalent fatigue load-stress relationship, the maximum stress range and cycle number (Si, ni) of the tower circumference are calculated, and the equivalent maximum fatigue damage Dmax of the tower circumference life cycle is calculated.

[0046] The present application divides the tower circumference weld fatigue hot spot according to the wind rose diagram, which can be divided into any equal parts (example: divided into 16 equal parts), to obtain an equivalent fatigue load of the tower circumference weld hot spot corresponding to different cabin azimuth angles; the present application sorts the equivalent load of the tower circumference weld fatigue hot spot and the occurrence time probability of each sector according to the size, to obtain the corresponding sequence of the optimized equivalent fatigue load and occurrence time probability of each sector, and then obtain the equivalent maximum equivalent fatigue load of the tower circumference.

[0047] The present application adopts tower fatigue load accumulation based on wind direction frequency distribution, which can effectively reduce the equivalent fatigue load of the tower weld, thereby reducing the weight of the tower of the wind turbine generator set, saving the amount of steel material, reducing the weight of the tower of the wind turbine generator set, thereby reducing the investment cost of the wind turbine generator set. The life prediction of the tower fatigue weld can master the fatigue life state of the tower as soon as possible or in real time. The output state (power generation hours) and the remaining life of the wind turbine generator set at the site are not equal, so the life prediction can be based on the site, and the output of the whole field can be controlled, for example, in the power limiting state, the generator set with low predicted life is stopped first, so as to achieve the optimal life and power generation of the whole field wind turbine generator set; the tower life is predicted as soon as possible, and if the predicted life exceeds the design life, the sector management of the tower life can be carried out to reduce the fatigue damage of the dangerous point Pj on the circumference.

[0048] In specific application, the above-mentioned accumulation method is applied to the operation optimization of the wind turbine generator set, and the specific steps are:​

[0049] 1) Obtain the yaw angle of the nacelle, and convert the yaw angle of the nacelle into the absolute yaw position according to the calibrated relative position relationship; divide the circumference of the tower of the wind turbine generator set into corresponding sectors, and calculate the average yaw angle of the nacelle within a preset time;

[0050] Obtain the wind speed, calculate the average wind speed Vave and effective turbulence intensity Ieff within a preset time;

[0051] 2) Correspondingly extend the average yaw angle of the nacelle, the average wind speed Vave and the effective turbulence intensity Ieff to the whole life cycle of the wind turbine generator set, and predict the hot spot P of the circumferential weld of the tower j The cumulative equivalent fatigue load M pj_sector_prediction of each sector is obtained.

[0052] 3) According to the equivalent fatigue index m of the material, the equivalent fatigue load DEL j of the point P prediction of the circumferential weld of the tower is calculated, and according to the equivalent fatigue load-stress relationship, the maximum stress range and the cycle number of the circumferential weld of the tower are calculated, and finally the maximum fatigue damage D j of the point P max_prediction of the circumferential weld of the tower is obtained.

[0053] 4) Compare the maximum fatigue damage D max_prediction with Dmax obtained by the above cumulative method; if D max_prediction >Dmax, yaw sector management control is performed to adjust the yaw position of the nacelle to reduce the maximum fatigue damage of the point P j of the circumferential weld of the tower; otherwise, continue to operate according to the current operation strategy.

[0054] The fatigue life of the tower of the wind turbine generator set is judged whether it is within the design range by correcting the design calculation value of the wind direction frequency distribution of the specific site micro-siting and the yaw angle of the operation of the unit, or the fatigue damage accumulation calculation is carried out online according to the management of the remaining fatigue life and the principle of minimum loss of power generation, to obtain the optimal yaw angle operation sector. If it is not within the operation design range, the operation sector of the wind turbine generator set is optimized, the optimal yaw angle of the unit is adjusted, the fatigue damage of the tower at a specific position is reduced, and the system is optimized.

[0055] The application will be further described below in combination with a specific complete embodiment:

[0056] 1. The yaw angle of the nacelle is collected by the nacelle yaw position sensor, and the yaw angle of the nacelle collected by the nacelle yaw position sensor is converted into the absolute yaw position according to the calibrated relative position relationship; the circumference of the tower of the wind turbine generator set is divided into corresponding sectors, and the average yaw angle of the nacelle within 10 minutes is calculated.

[0057] The wind speed is collected by the nacelle wind speed sensor, and the wind speed is corrected. The wind speed is averaged for 10 minutes to calculate the average wind speed Vave and effective turbulence intensity Ieff every 10 minutes. The time period is synchronized with the nacelle yaw azimuth clock;

[0058] 2. The running data of the above unit is extended to the whole life cycle to predict the tower circumference weld hot spot P j The cumulative equivalent fatigue load M pj_sector_prediction of each sector;

[0059] Specifically, the wind speed Weibull distribution and reference turbulence intensity Iref of the wind turbine during the running time t are obtained according to the average nacelle running azimuth angle, average wind speed Vave and effective turbulence intensity Ieff;

[0060] Based on the wind speed Weibull distribution and reference turbulence intensity Iref during the running time t, the equivalent fatigue load of the wind turbine during the running time t is calculated by the calibrated load calculation simulation model.

[0061] According to the damage linear accumulation principle, the equivalent fatigue load of the wind turbine during the running time t is extended to the cumulative equivalent fatigue load of the design life T (such as 20 years).

[0062] Table 1 P j point equivalent fatigue load calculation result

[0063]

[0064]

[0065] The wind direction rose diagram of the running time t is shown in Figure 3 , and the equivalent fatigue load of the circumference Pj point of the design life T (20 years) is shown in Table 1.

[0066] 3. According to the equivalent fatigue index m of the material, the equivalent fatigue load DEL j of the tower circumference P prediction is calculated, and according to the equivalent fatigue load-stress relationship, the maximum stress range and cycle number (Si, ni) of the tower circumference are calculated, and the maximum fatigue damage D j of the tower circumference point P max_prediction is obtained.

[0067] 4. The predicted maximum fatigue damage is compared with the equivalent maximum fatigue damage Dmax of the tower circumference life cycle; if the predicted maximum fatigue damage D max_predictionIf the equivalent maximum fatigue damage Dmax of the tower circumference life cycle is greater than the maximum fatigue damage Dmax, then according to the function relation F(DEL_opt, theta) of the equivalent fatigue damage of the tower circumference weld hot spot Pj and the sector management yaw azimuth angle, the yaw sector management control is executed, so that the cabin operation yaw position is adjusted, and the tower circumference point P j The maximum fatigue damage is predicted. max_prediction If the equivalent maximum fatigue damage Dmax of the tower circumference life cycle is less than or equal to the maximum fatigue damage Dmax, then the unit continues to operate according to the current operation strategy.

[0068] The function relation F(DEL_opt, theta) is shown in Table 1. Since the equivalent fatigue load of the tower circumference point Pj corresponding to different wind directions theta is not the same (the fourth column of Table 1), the function relation F(DEL_opt, theta) of the equivalent fatigue damage of Pj and the sector management yaw azimuth angle is constructed. That is, if the damage corresponding to the Pj point exceeds the set value, the wind turbine unit is adjusted to operate in a sector according to the calculation of Table 1 (that is, the operation time in the wind direction theta is adjusted, so that the operation time of the Pj point under large load is reduced, and the fatigue damage of the design life is reduced).

[0069] By introducing the wind speed of the cabin anemometer and the yaw azimuth angle sensor data, and performing data clock synchronization, the 10-minute average yaw azimuth angle, average wind speed and turbulence intensity are obtained, the function relation expression of the tower circumference weld hot spot fatigue damage and the yaw azimuth angle is constructed, the operation sector management of the unit is realized, and the equivalent fatigue load of the maximum damage position of the tower circumference weld is reduced.

[0070] The tower fatigue load prediction of a specific site is adopted to judge whether the tower fatigue life of the unit is within the design range, and the function relation of the equivalent fatigue load of the tower circumference weld and the yaw azimuth angle is constructed, the fatigue damage accumulation calculation is performed online, when the predicted equivalent fatigue load of the operation is greater than the design value, the sector management control is executed, the operation sector of the wind turbine unit is optimized, the optimal unit operation yaw azimuth angle is adjusted, the fatigue damage of the tower in a specific direction is reduced, the system is optimized, and the reliability of the wind turbine unit is improved.

[0071] The application also discloses a tower fatigue load accumulation system based on wind direction frequency distribution, which comprises:

[0072] The first module is used for acquiring the wind frequency distribution P(theta) of each sector of a specific site, the Weibull distribution parameters (A, k) of each sector, and the effective turbulence intensity Ieff of each sector.

[0073] The second module is used for obtaining the cabin azimuth angle theta and the tower circumference weld hot spot P jcorresponding equivalent fatigue load M pj (θ) ;

[0074] a third module for sorting the wind frequency distribution P(θ) of each sector; tower circumference weld hot spot P j corresponding equivalent fatigue load M pk (θ) sorting; according to the fatigue curve index m of the material and the corresponding M after sorting pj (θ) and P(θ), the equivalent fatigue load of all sectors is equivalently converted to get the equivalent tower circumference maximum value DEL_Max;

[0075] a fourth module for calculating the tower circumference maximum stress range and the cycle number according to the equivalent fatigue load-stress relationship, and calculating the equivalent maximum fatigue damage Dmax of the tower circumference life cycle.

[0076] The system of the present application, for executing the method as described above, also has the advantages as described above.

[0077] The application further discloses a computer readable storage medium, which stores a computer program, and the computer program performs the steps of the wind direction frequency distribution based tower fatigue load accumulation method when executed by a processor. The application also discloses a computer device, which comprises a memory and a processor, and the memory stores a computer program, and the computer program performs the steps of the wind direction frequency distribution based tower fatigue load accumulation method when executed by the processor. The application implements all or part of the processes of the above-mentioned embodiment method, and can also be completed by a computer program instructing related hardware. The computer program can be stored in a computer readable storage medium, and the computer program can implement the steps of the above-mentioned method embodiments when executed by a processor. The computer program comprises computer program code, which can be in the form of source code, object code, an executable file or some intermediate form. The computer readable medium can comprise any entity or device capable of carrying the computer program code, a recording medium, a U disk, a mobile hard disk, a magnetic disk, an optical disk, a computer memory, a read-only memory (ROM), a random access memory (RAM), an electrical carrier signal, a telecommunication signal and a software distribution medium, etc. The memory can be used to store computer programs and / or modules, and the processor can realize various functions by running or executing the computer programs and / or modules stored in the memory and calling data stored in the memory. The memory can comprise a high-speed random access memory and can also comprise a non-volatile memory, for example, a hard disk, a memory, a plug-in hard disk, a smart media card (SMC), a secure digital (SD) card, a flash card, at least one magnetic disk storage device, a flash memory device or other volatile solid-state memory device, etc.

[0078] The above is only the preferred embodiment of the application, and the protection scope of the application is not limited to the above-mentioned embodiment. Any technical solution falling within the concept of the application belongs to the protection scope of the application. It should be noted that some improvements and refinements made by those skilled in the art without departing from the principle of the application should be considered as the protection scope of the application.

Claims

1. A method for accumulating tower fatigue loads based on wind direction frequency distribution, characterized in that, Including the following steps: S1. Obtain the wind frequency distribution of each sector at a specific site. Weibull distribution parameters and effective turbulence intensity Ieff of each sector; S2. Based on the Weibull distribution parameters and the effective turbulence intensity Ieff of each sector, the nacelle azimuth angle is calculated through load calculation. Hot spots of circumferential welds on tower Corresponding equivalent fatigue load ; S3. Distribute the wind frequency of each sector. Sort by size from largest to smallest; identify the hot spots of the circumferential welds of the tower. Corresponding equivalent fatigue load Sort from largest to smallest; based on the fatigue curve index m of the material and the corresponding... and The equivalent fatigue load of all sectors is equivalently transformed to obtain the equivalent maximum value of the tower circumference, DEL_Max. S4. Based on the equivalent fatigue load-stress relationship, the maximum stress range and number of cycles of the tower circumference are calculated, and the equivalent maximum fatigue damage Dmax of the tower circumference life cycle is calculated.

2. The tower fatigue load accumulation method based on wind direction frequency distribution according to claim 1, characterized in that, The specific process of step S2 is as follows: Divide the wind rose diagram into n equally divided sectors. Assuming that the azimuth of the unit is at the center of each sector, then solve for the wind direction at each sector. On the circumference of the tower corresponding to the position , , Point equivalent fatigue load .

3. The tower fatigue load accumulation method based on wind direction frequency distribution according to claim 2, characterized in that, In step S3, the wind direction weight of each sector in the wind rose diagram is used to adjust the wind direction around the tower circumference. , , Accumulated equivalent fatigue load at points, hot spots of the circumferential weld of the tower. The equivalent transformation is performed according to the following formula: 。 4. The tower fatigue load accumulation method based on wind direction frequency distribution according to claim 3, characterized in that, The value of n is between 10 and 20.

5. The tower fatigue load accumulation method based on wind direction frequency distribution according to any one of claims 1 to 4, characterized in that, In step S1, the micro-situation results of each turbine site in the wind farm are obtained based on fluid dynamics simulation, and the wind frequency distribution of each sector of the turbine site at a specific site is obtained. Weibull distribution parameters and effective turbulence intensity Ieff of each sector.

6. A tower fatigue load accumulation system based on wind direction frequency distribution, used to perform the steps of the tower fatigue load accumulation method based on wind direction frequency distribution as described in any one of claims 1 to 5, characterized in that, include: The first module is used to obtain the wind frequency distribution of each sector at a specific site. Weibull distribution parameters and effective turbulence intensity Ieff of each sector; The second module is used to calculate the nacelle azimuth angle based on the Weibull distribution parameters and the effective turbulence intensity Ieff of each sector through load calculation. Hot spots of circumferential welds on tower Corresponding equivalent fatigue load ; The third module is used to distribute the wind frequency of each sector. Sort by size from largest to smallest; identify the hot spots of the circumferential welds of the tower. Corresponding equivalent fatigue load Sort from largest to smallest; based on the fatigue curve index m of the material and the corresponding... and The equivalent fatigue load of all sectors is equivalently transformed to obtain the equivalent maximum value of the tower circumference, DEL_Max. The fourth module is used to calculate the maximum stress range and number of cycles around the tower circumference based on the equivalent fatigue load-stress relationship, and to calculate the equivalent maximum fatigue damage Dmax of the tower circumference life cycle.

7. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is run by the processor, it executes the steps of the tower fatigue load accumulation method based on wind direction frequency distribution as described in any one of claims 1 to 5.

8. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the computer program is run by the processor, it executes the steps of the tower fatigue load accumulation method based on wind direction frequency distribution as described in any one of claims 1 to 5.

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