Wind turbine nacelle transfer function partition fitting method based on wind speed and wind direction

Abstract

The application discloses a wind turbine generator set cabin transfer function partition fitting method based on wind speed and wind direction, and comprises the following steps: obtaining the windward area of the blade; calculating the eccentric torque of the wind turbine generator set according to the windward area of the blade, and partitioning according to the eccentric torque value; calculating the cabin transfer function according to the torque partition, and calculating the fitting function order respectively. In the application, the wind speed at the hub height H is taken as the average wind speed of the wind blade of the wind turbine generator set, the pressure on the wind wheel is calculated, the direction of the wind is collected, the angle between the wind direction and the wind blade is calculated, and the windward area of the blade is calculated according to the calculation of the windward area of the wind blade according to the wind direction and the angle between the wind direction and the wind blade. The eccentric torque of the wind turbine generator set is calculated according to the windward area of the blade, the eccentric torque value is partitioned, the rated eccentric torque partition threshold is set, the low-torque zone, the medium-torque zone and the high-torque zone are obtained, and the cabin transfer function is calculated, so that the calculation precision is effectively guaranteed, the fitting error is reduced, and the correction accuracy is improved.

Description

Technical Field

[0001] This invention belongs to the field of wind turbine performance evaluation and optimization technology, specifically involving a method for partitioning and fitting the transfer function of wind turbine nacelle based on wind speed and wind direction. Background Technology

[0002] In recent years, with the development of new energy technologies, wind power generation has experienced rapid growth, leading to a significant increase in wind turbine units. Ensuring the safe and stable operation of these units has become a major concern. During wind turbine operation, performance evaluation and optimization are crucial. The actual power curve of the turbine is an important reference factor in this evaluation and optimization. Obtaining the power curve requires testing the nacelle wind speed, and the calculation process necessitates corrections. The nacelle transfer function is a key parameter for wind speed correction. However, existing nacelle transfer function calculations are often fuzzy, making them unsuitable for applications requiring high accuracy in wind speed correction. This results in fitting errors and a limited applicability. Summary of the Invention

[0003] To address the technical problems existing in the prior art, the purpose of this invention is to provide a method for partitioning and fitting the transfer function of wind turbine nacelles based on wind speed and wind direction.

[0004] To achieve the above objectives and technical effects, the technical solution adopted by this invention is as follows:

[0005] The wind turbine nacelle transfer function partitioning fitting method based on wind speed and wind direction includes the following steps:

[0006] Obtain the windward area of ​​the blades;

[0007] The eccentric torque of the wind turbine is calculated based on the windward area of ​​the blades, and the turbine is divided into zones according to the eccentric torque value.

[0008] The transfer function of the computer cabin is calculated based on the torque partition, and the order of the fitting function is calculated respectively.

[0009] Furthermore, the steps for obtaining the windward area of ​​the blades include:

[0010] Collect the wind direction, calculate the angle between the wind direction and the blades, and calculate the windward area of ​​the blades based on the windward area of ​​the blades.

[0011] Furthermore, the windward area Sh of the wind turbine blade is calculated using the following formula:

[0012] Sh=Sz*sinθ

[0013] Where Sz is the frontal wind-receiving area of ​​the wind turbine blade, and θ is the angle between the wind direction and the wind turbine blade.

[0014] Furthermore, the steps of calculating the eccentric torque of the wind turbine based on the windward area of ​​the blades and dividing the turbine into zones based on the eccentric torque value include:

[0015] The wind speed at the hub height H is taken as the average wind speed of the wind turbine blades. The pressure on the wind turbine is calculated, and the eccentric torque of the wind turbine is calculated by combining the windward area of ​​the blades and the eccentricity of the wind turbine center.

[0016] A rated eccentric torque zoning threshold is set as the zoning boundary value. Based on the eccentric torque value, the engine room is divided into low torque zone, medium torque zone and high torque zone. The nacelle transfer function of the three zones is calculated independently.

[0017] Furthermore, the eccentric torque Mz of the wind turbine is calculated using the following formula:

[0018] M Z =P H She W

[0019] Among them, P H Where is the pressure on the wind turbine, Sh is the windward area of ​​the blades, and e is the pressure on the wind turbine. W It is the eccentricity of the wind turbine center.

[0020] Furthermore, the pressure P on the wind turbine H Calculated using the following formula:

[0021]

[0022] Among them, C FB =8 / 9; ρ is the air density, ρ = 1.23 kg / m³ 3 Vh is the wind speed at the hub height H of the wind turbine.

[0023] Furthermore, the eccentricity e at the center of the wind turbine W Calculated using the following formula:

[0024]

[0025] in, R is the radius of the wind turbine.

[0026] Furthermore, the wind speed Vh of the wind turbine at hub height H is calculated using the following formula:

[0027] Vh = Vz (Hz / Hh) a

[0028] Where Hz and Hh are the heights at points Z and H, respectively, and a is the wind shear coefficient.

[0029] Furthermore, the wind shear coefficient α is calculated using the following formula:

[0030]

[0031] Where Vc is the wind speed at point C, Vb is the wind speed at point B, and Hc and Hb are the heights at points C and B, respectively.

[0032] Furthermore, when calculating the engine room transfer function based on the torque partition, the engine room operating data is first obtained, and then the required engine room transfer function is obtained through a higher-order polynomial.

[0033] The nacelle operating data includes: wind speed, active power, generator speed, data below the grid-connected speed of the wind turbine, and power limitation data.

[0034] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0035] This invention discloses a method for partitioning and fitting the transfer function of a wind turbine nacelle based on wind speed and direction. The method calculates the pressure on the rotor by using the wind speed at hub height H as the average wind speed of the turbine blades; it collects the wind direction, calculates the angle between the wind direction and the blades, and calculates the windward area of ​​the blades based on the windward area of ​​the blades; it calculates the eccentric torque of the wind turbine based on the windward area of ​​the blades, partitions the turbine based on the eccentric torque value, and sets a threshold for the rated eccentric torque partition to obtain low-torque, medium-torque, and high-torque zones. This effectively ensures calculation accuracy, reduces fitting errors, and improves correction accuracy. Detailed Implementation

[0036] The present invention will now be described in detail so that its advantages and features can be more easily understood by those skilled in the art, thereby providing a clearer and more explicit definition of the scope of protection of the present invention.

[0037] The following provides a brief overview of one or more aspects to offer a basic understanding of them. This overview is not an exhaustive summary of all conceived aspects, nor is it intended to identify all key or decisive elements. Its sole purpose is to present some concepts of one or more aspects in a simplified form to prepare for the more detailed descriptions that follow.

[0038] The wind turbine nacelle transfer function partitioning fitting method based on wind speed and wind direction includes the following steps:

[0039] S1. Obtain the height data of the wind turbine and the length of the blades, and calculate the frontal wind-receiving area of ​​the blades.

[0040] S2. Calculate the wind shear coefficient, and simultaneously collect the wind speed of the wind turbine at point Z, and determine the hub height H of the wind turbine.

[0041] S3. Based on the wind shear coefficient and the wind speed of the wind turbine at point Z, calculate the wind speed of the wind turbine at hub height H.

[0042] S4. Using the wind speed at hub height H as the average wind speed of the wind turbine blades, calculate the pressure on the wind turbine.

[0043] S5. Collect the wind direction, calculate the angle between the wind direction and the blades, and calculate the windward area of ​​the blades based on the windward area of ​​the blades.

[0044] S6. Calculate the eccentric torque of the wind turbine based on the windward area of ​​the blades, divide the area into zones according to the eccentric torque value, set the rated eccentric torque zone threshold, and obtain the low torque zone, medium torque zone and high torque zone.

[0045] S7. Calculate the order of the fitting function based on the transfer function of the torque partition computer compartment.

[0046] In step S2, the calculation steps for the wind shear coefficient are as follows:

[0047] Let the wind shear coefficient be a. Collect the wind speed Vc at point C and Vb at point B of the wind turbine. The heights of points C and B are Hc and Hb, respectively. Then, calculate the wind shear coefficient using the following formula:

[0048]

[0049] In step S3, the wind speed Vh at the hub height H of the wind turbine is calculated using the following formula:

[0050] Vh = Vz (Hz / Hh) a

[0051] Where Hz and Hh are the heights of points Z and H, respectively.

[0052] In step S5, the windward area is the effective area of ​​the blade subjected to wind force. Let the windward area of ​​the blade be Sh, and the forward windward area of ​​the blade be Sz obtained through measurement or design data. Given that the angle between the wind direction and the blade is θ, the windward area Sh of the blade is calculated using the following formula:

[0053] Sh=Sz*sinθ

[0054] In step S6, the eccentric torque Mz of the wind turbine is calculated using the following formula:

[0055] M Z =P H She W

[0056] Where Sh is the windward area of ​​the blade, and P H For the pressure on the wind turbine, e W It is the eccentricity of the wind turbine center.

[0057] Pressure P on the wind turbine H Calculated using the following formula:

[0058]

[0059] Among them, C FB =8 / 9; ρ is the air density, ρ = 1.23 kg / m³ 3 .

[0060] eccentricity e at the center of the wind turbine W Calculated using the following formula:

[0061]

[0062] in, R is the radius of the wind turbine.

[0063] In step S6, after calculating the eccentric torque of the wind turbine, the torque value set is obtained by measuring the eccentric torque values ​​at different times, and a coordinate system of torque data and time variation function is established.

[0064] In step S6, the rated eccentric torque partition threshold is set as the partition boundary value, and its torque partition threshold is set as two sets of distinguishing thresholds. It is divided into three regions by two intermediate boundary values, and the nacelle transfer function of the three regions is calculated independently.

[0065] Step S7, which involves calculating the order of the fitting function based on the transfer function of the torque partition computer compartment, includes:

[0066] Because the control strategies of the generator set differ at different stages, the nacelle transfer function changes. This invention, based on the three regions—low torque, medium torque, and high torque—formed in step S6, uses a high-order polynomial for fitting and approximation in each region to reduce fitting errors. The polynomial of the nacelle transfer function can be expressed as:

[0067] y = a n x n +…+a1x+a0,n≥1

[0068] The coefficients a0-a of the above polynomial are obtained by calculating using the least squares method. n .

[0069] The transfer function of the cabin is:

[0070]

[0071] Where X is the nacelle wind speed, Y is the wind speed of the wind measuring tower at the hub height H, j, l, and k are the orders of the fitting functions in the low torque region, medium torque region, and high torque region, respectively, Vin is the cut-in wind speed, Vout is the cut-out wind speed, and Ve is the rated wind speed.

[0072] Example 1

[0073] Assuming the wind shear coefficient a = 0.136, and the wind speed at a height of 60 meters for the wind turbine as V60, then the wind speed V100 at a hub height of 100 meters is calculated as follows:

[0074] V100 = V60(60 / 100) 0.136

[0075] The windward area of ​​the blades is Sz = 102m² 2 If the angle between the wind direction and the blades is θ = 78°, then the windward area of ​​the blades is Sh = Sz * sinθ = 10² * sin78 = 99.8 m² 2 .

[0076] Pressure P on the wind turbine H Calculated using the following formula:

[0077]

[0078] eccentricity e at the center of the wind turbine W Calculated using the following formula:

[0079]

[0080] The eccentric torque Mz of the wind turbine is calculated using the following formula:

[0081] M Z =P H She W

[0082] By comparing Mz with a set threshold, the range of the cabin transfer function fitting calculation partition is determined, thereby improving the accuracy of cabin transfer function partition fitting, effectively ensuring calculation accuracy, reducing fitting error, and improving correction accuracy.

[0083] Any parts or structures not specifically described in this invention can be made using existing technologies or products, and will not be elaborated upon here.

[0084] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention specification, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A method for partitioning and fitting the transfer function of a wind turbine nacelle based on wind speed and direction, characterized in that, Includes the following steps: Obtain the windward area of ​​the blades; The eccentric torque of the wind turbine is calculated based on the windward area of ​​the blades, and the turbine is divided into zones according to the eccentric torque value. The transfer function of the computer cabin is calculated based on the torque partition, and the order of the fitting function is calculated respectively; The steps to obtain the windward area of ​​the blades include: Collect the wind direction, calculate the angle between the wind direction and the blades, and calculate the windward area of ​​the blades based on the windward area of ​​the blades. The steps for calculating the eccentric torque of a wind turbine based on the windward area of ​​the blades and dividing the turbine into zones based on the eccentric torque value include: The wind speed at the hub height H is taken as the average wind speed of the wind turbine blades. The pressure on the wind turbine is calculated, and the eccentric torque of the wind turbine is calculated by combining the windward area of ​​the blades and the eccentricity of the wind turbine center. A rated eccentric torque zoning threshold is set as the zoning boundary value. Based on the eccentric torque value, the engine room is divided into low torque zone, medium torque zone and high torque zone. The nacelle transfer function of the three zones is calculated independently.

2. The method for partitioning and fitting the transfer function of a wind turbine nacelle based on wind speed and direction according to claim 1, characterized in that, The windward area Sh of the blade is calculated using the following formula: ； Where Sz is the frontal wind-receiving area of ​​the wind turbine blade, and θ is the angle between the wind direction and the wind turbine blade.

3. The method for partitioning and fitting the transfer function of a wind turbine nacelle based on wind speed and direction according to claim 1, characterized in that, The eccentric torque of the wind turbine Calculated using the following formula: ； in, Where is the pressure on the wind turbine, and Sh is the windward area of ​​the blades. It is the eccentricity of the wind turbine center.

4. The method for partitioning and fitting the transfer function of a wind turbine nacelle based on wind speed and direction according to claim 3, characterized in that, The pressure on the wind turbine Calculated using the following formula: ； Among them, C FB =8 / 9; ρ is the air density, ρ=1.23Kg / m³ 3 Vh is the wind speed at the hub height H of the wind turbine.

5. The method for partitioning and fitting the transfer function of a wind turbine nacelle based on wind speed and direction according to claim 3, characterized in that, The eccentricity of the wind turbine center Calculated using the following formula: ； Where R is the radius of the wind turbine and Vh is the wind speed at the hub height H of the wind turbine.

6. The method for partitioning and fitting the transfer function of a wind turbine nacelle based on wind speed and direction according to claim 4, characterized in that, The wind speed Vh at hub height H of the wind turbine is calculated using the following formula: Vh=Vz(Z / H) a ; Where Z and H are altitudes, and a is the wind shear coefficient.

7. The method for partitioning and fitting the transfer function of a wind turbine nacelle based on wind speed and direction according to claim 6, characterized in that, The wind shear coefficient α is calculated using the following formula: ； Where Vc is the wind speed at point C, Vb is the wind speed at point B, and Hc and Hb are the heights at points C and B, respectively.

8. The method for partitioning and fitting the transfer function of a wind turbine nacelle based on wind speed and direction according to claim 1, characterized in that, When calculating the engine room transfer function based on the torque partition, the engine room operating data is first obtained, and then the required engine room transfer function is obtained through a higher-order polynomial. The nacelle operating data includes: wind speed, active power, generator speed, data below the grid-connected speed of the wind turbine, and power limitation data.

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