A method for simplifying the processing of the load spectrum of the main gearbox bearing of a wind turbine

Abstract

A method for simplifying the processing of the bearing load spectrum of a wind turbine main gearbox, comprising the following steps: 1) Collect the loads of each degree of freedom of the bearings of the wind turbine main gearbox, and take the absolute value of the data with the load less than zero on the degree of freedom M z to obtain the original load spectrum containing a number of loads; 2) Arrange and combine the load information in the original load spectrum according to the positive and negative of the loads on each degree of freedom to obtain the load information of 16 different working conditions; 2-3) Arrange and combine the load information about F +x , F ‑x , F +y , F +z , F ‑z , M +x , M ‑x , M +y , M ‑y , M +x to obtain the load information of 16 different working conditions; 3) Calculate the cumulative time; 4) Calculate the cumulative number of revolutions; 5) Calculate the average rotational speed; 6) Calculate the equivalent values of the load spectra corresponding to the positive and negative loads on different degrees of freedom respectively; 7) Correspondingly combine the average rotational speed, the cumulative time, and the equivalent values of the load spectra corresponding to the positive and negative loads on different degrees of freedom in the original load spectrum to form a simplified load spectrum.

Description

Technical Field

[0001] The present invention relates to the field of wind power gearboxes, and in particular to a method for simplifying the processing of a bearing load spectrum of a main gearbox of a wind turbine generator set. Background Art

[0002] At present, wind turbines with three-point support structures are widely used, but the input shaft and bearings of their main gearboxes must withstand six degrees of freedom loads, namely F x 、F y 、F z 、M x 、M y 、M z The forces and torques on each degree of freedom make the working conditions of bearings very complicated, and fatigue load analysis is time-consuming and laborious.

[0003] According to relevant standards, in order to ensure the accuracy of the load calculation results on the bearing, the load spectrum of the bearing must be fully calculated based on 6 degrees of freedom to comprehensively judge whether the bearing selected on the main gearbox meets the design requirements. For example, after processing the bearing load of the main gearbox according to the method described in "A Load Processing Method for the Main Bearing of a Wind Turbine Gearbox" with publication number CN113051679A, a load spectrum containing 64 working conditions can be obtained. Inputting the load spectrum into the wind turbine design software for fatigue load analysis requires a considerable amount of calculation time, resulting in a delay in the design progress of the main gearbox. A method for simplifying the processing of the load spectrum of the main gearbox bearing of the wind turbine is urgently needed to ensure the calculation accuracy while simplifying the number of bearing load spectra, improve design efficiency, and shorten the design cycle of the main gearbox. Summary of the invention

[0004] The purpose of the present invention is to address the corresponding deficiencies in the prior art and provide a method for simplifying the processing of the load spectrum of the main gearbox bearing of a wind turbine set, delete the load data that is unnecessary for the calculation, simplify the number of bearing load spectra, and improve the calculation efficiency while ensuring the accuracy of the calculation results. The design cycle of the main gearbox is reduced, and the design efficiency of the main gearbox is effectively improved.

[0005] The object of the present invention is achieved by adopting the following scheme: A method for simplifying the processing of the load spectrum of the main gearbox bearing of a wind turbine generator system comprises the following steps:

[0006] 1) Collect the loads of each degree of freedom of the main gearbox bearing of the wind turbine and calculate the degree of freedom M z The data with load less than zero are taken as absolute values ​​to obtain the original load spectrum containing several loads, which is included in the degrees of freedom F x 、F y 、F z 、Mx 、M y 、M z Load information obtained by upsampling;

[0007] 2) The load information in the original load spectrum is arranged and combined according to the positive and negative values ​​of the loads on each degree of freedom to obtain the load information of 16 different working conditions:

[0008] 2-1) Assume that the positive loads on different degrees of freedom are as follows:

[0009] In degrees of freedom F x The load greater than or equal to zero is F +x , in degrees of freedom F y The load greater than or equal to zero is F +y , in degrees of freedom F z The load greater than or equal to zero is F +z , in degrees of freedom M x The load greater than or equal to zero is M +x , in degrees of freedom M y The load greater than or equal to zero is M +y , in degrees of freedom M z The load greater than or equal to zero is M +z ;

[0010] 2-2) Assume that the loads on different degrees of freedom are as follows:

[0011] In degrees of freedom F x The load less than zero is F -x , in degrees of freedom F z The load less than zero is F -z , in degrees of freedom M x The load less than zero is M -x , in degrees of freedom M y The load less than zero is M -y ;

[0012] 2-3) The original load spectrum about F +x 、F -x 、F +y 、F +z 、F -z 、M +x 、M -x 、M +y 、M -y 、M +x The load information of 16 different working conditions is obtained by arranging and combining the load information of 16 different working conditions;

[0013] 3) Calculate the accumulation time of load information in the original load spectrum;

[0014] 4) Calculate the cumulative number of revolutions of the load information in the original load spectrum;

[0015] 5) Divide the accumulated number of revolutions by the accumulated time to obtain the average speed of the load information in the original load spectrum;

[0016] 6) Calculate the equivalent values ​​of the load spectrum corresponding to the positive and negative loads on different degrees of freedom in the original load spectrum;

[0017] 7) The average rotation speed, cumulative time of the load information in the original load spectrum, and the load spectrum equivalent values ​​corresponding to the positive and negative loads on different degrees of freedom in the original load spectrum are matched one by one to form a simplified load spectrum.

[0018] Preferably, the load spectrum equivalent value is calculated according to the following formula:

[0019] [D(k)]=[∑([f i (k)] p ·n i ) / ∑n i ] 1 / p

[0020] Where [D(k)] is the equivalent value of the load spectrum corresponding to load k, [f i (k)] is the load corresponding to load k under the i-th working condition in the original load spectrum, p is the life index used to calculate the bearing shaft life in the standard number IEC61400-4, n i is the number of revolutions corresponding to the i-th condition in the original load spectrum.

[0021] Preferably, the lifespan index is 3.33.

[0022] Preferably, the cumulative time of the load information in the original load spectrum is obtained by summing up all load times included in the load information in the original load spectrum.

[0023] Preferably, the cumulative number of revolutions of the load information in the original load spectrum is obtained by summing up all the numbers of revolutions included in the load information in the original load spectrum.

[0024] The advantages of the present invention are as follows:

[0025] ① The amount of load information in the simplified load spectrum obtained by the present invention is less than that in the conventional load spectrum, and the calculation efficiency is high;

[0026] ② The load information of each working condition in the simplified load spectrum obtained by the present invention is unique, non-repetitive and non-omitted, thus ensuring the accuracy of the calculation results;

[0027] ③ The simplified load spectrum obtained by the present invention is suitable for the design of a fast and effective propulsion main gearbox. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1It is a flow chart of the present invention. DETAILED DESCRIPTION

[0029] like Figure 1 As shown, a method for simplifying the processing of the load spectrum of the main gearbox bearing of a wind turbine generator system comprises the following steps:

[0030] 1) Collect the loads of each degree of freedom of the main gearbox bearing of the wind turbine and calculate the degree of freedom M z The data with load less than zero are taken as absolute values ​​to obtain the original load spectrum containing several loads, which is included in the degrees of freedom F x 、F y 、F z 、M x 、M y 、M z Load information obtained by upsampling;

[0031] The original load spectrum contains 8 columns of data, which correspond to the degrees of freedom F x 、F y 、F z 、M x 、M y 、M z The load information under different working conditions is collected at a certain sampling time interval, and the number of revolutions at the center of the wheel hub and the degree of freedom F x 、F y 、F z 、M x 、M y 、M z The load information consists of the load value on the load sensor, that is, the load information includes the load value, time and number of revolutions.

[0032] 2) The load information in the original load spectrum is arranged and combined according to the positive and negative values ​​of the loads on each degree of freedom to obtain the load information of 16 different working conditions:

[0033] 2-1) Assume that the positive loads on different degrees of freedom are as follows:

[0034] In degrees of freedom F x The load greater than or equal to zero is F +x , in degrees of freedom F y The load greater than or equal to zero is F +y , in degrees of freedom F z The load greater than or equal to zero is F +z , in degrees of freedom M x The load greater than or equal to zero is M +x , in degrees of freedom M y The load greater than or equal to zero is M +y , in degrees of freedom M zThe load greater than or equal to zero is M +z ;

[0035] 2-2) Assume that the loads on different degrees of freedom are as follows:

[0036] In degrees of freedom F x The load less than zero is F -x , in degrees of freedom F z The load less than zero is F -z , in degrees of freedom M x The load less than zero is M -x , in degrees of freedom M y The load less than zero is M -y ;

[0037] The degrees of freedom F y represents the degree of freedom in the direction of gravity, so the degree of freedom F y There is no load less than zero, that is, there is only degree of freedom F y Positive load F on +y ;

[0038] Since the degree of freedom M z Only one direction of the bearing rotation needs to be considered, so the degree of freedom M in the original load spectrum z After taking the absolute value of the data with load less than zero, the degree of freedom M z There is no load less than zero, that is, there is only the degree of freedom M z Positive load M on +z ;

[0039] 2-3) The original load spectrum about F +x 、F -x 、F +y 、F +z 、F -z 、M +x 、M -x 、M +y 、M -y 、M +x The load information of 16 different working conditions is obtained by arranging and combining the load information of 16 different working conditions;

[0040] 3) Calculate the accumulation time of load information in the original load spectrum;

[0041] In this embodiment, the cumulative time of the load information in the original load spectrum is obtained by summing up all the load times included in the load information in the original load spectrum.

[0042] 4) Calculate the cumulative number of revolutions of the load information in the original load spectrum;

[0043] In this embodiment, the cumulative revolutions of the load information in the original load spectrum are obtained by summing up all revolutions included in the load information in the original load spectrum.

[0044] 5) Divide the accumulated number of revolutions by the accumulated time to obtain the average speed of the load information in the original load spectrum;

[0045] 6) Calculate the load spectrum equivalent values ​​corresponding to the positive and negative loads on different degrees of freedom in the original load spectrum respectively; in this embodiment, the load spectrum equivalent values ​​are calculated according to the following formula:

[0046] [D(k)]=[∑([f i (k)] p ·n i ) / ∑n i ] 1 / p

[0047] Where [D(k)] is the equivalent value of the load spectrum corresponding to load k, [f i (k)] is the load corresponding to load k under the i-th working condition in the original load spectrum, p is the life index used to calculate the bearing shaft life in the standard number IEC61400-4. In this embodiment, the life index is 3.33, n i is the number of revolutions corresponding to the i-th condition in the original load spectrum.

[0048] 7) The average speed, cumulative time of the load information in the original load spectrum, and the load spectrum equivalent values ​​corresponding to the positive and negative loads on different degrees of freedom in the original load spectrum are correspondingly formed into a simplified load spectrum, as shown in Table 1:

[0049] Table 1

[0050]

[0051] In Table 1, D(F +x ) represents the positive load F in the simplified load spectrum +x The corresponding load spectrum equivalent value, D(F -x ) represents the load F in the simplified load spectrum -x The corresponding load spectrum equivalent value, D(F +y ) represents the positive load F in the simplified load spectrum +y The corresponding load spectrum equivalent value, D(F +z ) represents the positive load F in the simplified load spectrum +z The corresponding load spectrum equivalent value, D(F -z ) represents the load F in the simplified load spectrum -z The corresponding load spectrum equivalent value, D(M +x ) represents the positive load M in the simplified load spectrum +x The corresponding load spectrum equivalent value, D(M -x) represents the load M in the simplified load spectrum -x The corresponding load spectrum equivalent value, D(M +y ) represents the positive load M in the simplified load spectrum +y The corresponding load spectrum equivalent value, D(M -y ) represents the load M in the simplified load spectrum -y The corresponding load spectrum equivalent value, D(M +z ) represents the positive load M in the simplified load spectrum +z (i.e., degrees of freedom M z The absolute value of the load on the load spectrum corresponds to the equivalent value of the load spectrum.

[0052] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modification made to the present invention by those skilled in the art without departing from the spirit of the present invention shall fall within the protection scope of the present invention.

Claims

1. A method for simplifying the processing of the load spectrum of the main gearbox bearing of a wind turbine, characterized in that: The following steps are involved: 1) Collect the loads of each degree of freedom of the main gearbox bearing of the wind turbine and calculate the degree of freedom M z The data with load less than zero are taken as absolute values ​​to obtain the original load spectrum containing several loads, which is included in the degrees of freedom F x 、F y 、F z 、M x 、M y 、M z Load information obtained by upsampling; 2) The load information in the original load spectrum is arranged and combined according to the positive and negative values ​​of the loads on each degree of freedom to obtain the load information of 16 different working conditions: 2-1) Assume that the positive loads on different degrees of freedom are as follows: In degrees of freedom F x The load greater than or equal to zero is F +x , in degrees of freedom F y The load greater than or equal to zero is F +y , in degrees of freedom F z The load greater than or equal to zero is F +z , in degrees of freedom M x The load greater than or equal to zero is M +x , in degrees of freedom M y The load greater than or equal to zero is M +y , in degrees of freedom M z The load greater than or equal to zero is M +z ; 2-2) Assume that the loads on different degrees of freedom are as follows: In degrees of freedom F x The load less than zero is F -x , in degrees of freedom F z The load less than zero is F -z , in degrees of freedom M x The load less than zero is M -x , in degrees of freedom M y The load less than zero is M -y ; 2-3) The original load spectrum about F +x 、F -x 、F +y 、F +z 、F -z 、M +x 、M -x 、M +y 、M -y 、M +x The load information of 16 different working conditions is obtained by arranging and combining the load information of 16 different working conditions; 3) Calculate the accumulation time of load information in the original load spectrum; 4) Calculate the cumulative number of revolutions of the load information in the original load spectrum; 5) Divide the accumulated number of revolutions by the accumulated time to obtain the average speed of the load information in the original load spectrum; 6) Calculate the equivalent values ​​of the load spectrum corresponding to the positive and negative loads on different degrees of freedom in the original load spectrum; 7) The average rotation speed, cumulative time of the load information in the original load spectrum, and the load spectrum equivalent values ​​corresponding to the positive and negative loads on different degrees of freedom in the original load spectrum are matched one by one to form a simplified load spectrum.

2. The method for simplifying the processing of the load spectrum of the main gearbox bearing of a wind turbine according to claim 1, characterized in that: The load spectrum equivalent value is calculated according to the following formula: [D(k)]=[∑([f i (k)] p ·n i ) / ∑n i ] 1 / p Where [D(k)] is the equivalent value of the load spectrum corresponding to load k, [f i (k)] is the load corresponding to load k under the i-th working condition in the original load spectrum, p is the life index used to calculate the bearing shaft life in the standard number IEC61400-4, n i is the number of revolutions corresponding to the i-th condition in the original load spectrum.

3. The method for simplifying the processing of the load spectrum of the main gearbox bearing of a wind turbine according to claim 2, characterized in that: The lifespan index is 3.

33.

4. The method for simplifying the processing of the load spectrum of the main gearbox bearing of a wind turbine according to claim 1, characterized in that: The cumulative time of the load information in the original load spectrum is obtained by summing up all the load times contained in the load information in the original load spectrum.

5. The method for simplifying the processing of the load spectrum of the main gearbox bearing of a wind turbine according to claim 1, characterized in that: The cumulative revolutions of the load information in the original load spectrum are obtained by summing up all revolutions included in the load information in the original load spectrum.

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