Construction Method of Additional Turbulence Intensity Calculation Model for Wind Turbines Applicable to Stable Atmosphere

Abstract

The present invention relates to a method for constructing a calculation model of additional turbulence intensity of a wind turbine suitable for a stable atmosphere. The present invention determines the relative wind direction angle of the inflow wind direction at each preset typical height relative to the inflow wind direction at the height of the wind turbine hub based on the inflow wind direction angles at multiple preset typical heights, and then fits the relationship between the vertical height and the relative wind direction angle, thereby determining the relative wind direction angle at each vertical height within the vertical height range of the wind wheel under a stable atmosphere in a simple and fast manner. Based on the relative wind direction angle at each vertical height, the present invention determines the lateral offset of the center point of the additional turbulence intensity profile in the horizontal plane at each vertical height caused by different wind directions from the first longitudinal plane at various locations downwind of the wind turbine, and then constructs a three-dimensional model of additional turbulence intensity and a ground effect correction function under a stable atmosphere based on the lateral offset, and forms a calculation model of additional turbulence intensity of a wind turbine suitable for a stable atmosphere based on the three-dimensional model of additional turbulence intensity and the ground effect correction function.

Description

Technical Field

[0001] The present invention relates to a method for constructing a calculation model of additional turbulence intensity of a wind turbine applicable to a stable atmosphere, which is applicable to the technical field of wind power generation. Background Art

[0002] In the wake region behind the wind turbine disk, the turbulence intensity is significantly higher than that in the incoming flow. This part of the increment is called "additional turbulence intensity", which is closely related to the recovery of the wind speed deficit in the wake region, and further affects the wind speed at the downstream wind turbine. Therefore, it is very necessary to consider the "additional turbulence intensity" when evaluating the wake effect between units and calculating the power generation.

[0003] Therefore, in recent years, the analytical modeling of additional turbulence intensity has received more and more attention. Among them, the IEC model has been widely used in wind power engineering practice due to its simple form and convenient calculation. However, because it ignores the spanwise variation of the additional turbulence intensity profile, there is a large deviation from the actual situation. In response to this, the calculation model proposed by Ishihara et al. uses a more realistic double-peak Gaussian function to describe the additional turbulence intensity and has thus been recognized by the academic community. However, through further in-depth research, it is found that it ignores the influence of the "wake expansion characteristic" and the treatment of the non-symmetrical characteristics of the three-dimensional distribution caused by the ground effect is not perfect, and the calculation accuracy needs to be further improved.

[0004] Moreover, the existing model methods represented by the IEC model and the Ishihara model all follow the neutral stratification hypothesis and do not consider the influence of atmospheric stability. So far, there is still a lack of research results on the wind turbine additional turbulence intensity model applicable to different atmospheric stabilities. In fact, on a daily time scale, the atmospheric stability will show an alternating cycle of neutral, stable, and convective changes, and long-term statistical data show that the atmospheric stability in a region will deviate from the neutral atmosphere to different degrees in different trends.

[0005] Research shows that compared with the neutral atmosphere, in the stable atmospheric state, the turbulence intensity in the incoming flow is lower, while the vertical shear of the wind direction profile increases significantly. Affected by this, the recovery rate of the additional turbulence intensity in the wind turbine wake region slows down. More importantly, its profile shape will be significantly tilted following the wind direction changes at different vertical heights, which is significantly different from the characteristic of being approximately symmetrically distributed about the longitudinal plane of the wind turbine in the neutral atmosphere. Restricted by this, if the existing model method is still used to calculate the additional turbulence intensity of the wind turbine in the stable atmosphere, a large calculation deviation will occur. Summary of the Invention

[0006] The technical problem to be solved by the present invention is: in view of the above problems, to provide a method for constructing a calculation model of additional turbulence intensity of a wind turbine applicable to a stable atmosphere.

[0007] The technical solution adopted by the present invention is as follows: A method for constructing an additional turbulence intensity calculation model for a wind turbine applicable to a stable atmosphere, which is applicable to a stable atmospheric state, includes:

[0008] Using a double-peak Gaussian function to describe the additional turbulence intensity profile in the horizontal plane at the hub height of the wind turbine, and gradually increasing the distance between the peak point and the center point of the profile as the distance from the wind turbine disk increases, forming an additional turbulence intensity two-dimensional model;

[0009] Obtaining the inflow wind direction angles at multiple preset typical heights within the first height range, and calculating the relative wind direction angles of the inflow wind direction angles at each preset typical height relative to the inflow wind direction angle at the hub height of the wind turbine;

[0010] Fitting the relative wind direction angles at each preset typical height to obtain the relationship between the vertical height and the relative wind direction angle;

[0011] Based on the relationship between the vertical height and the relative wind direction angle, determining the relative wind direction angles at each vertical height within the vertical height range of the wind turbine;

[0012] Based on the relative wind direction angles at each vertical height within the vertical height range of the wind turbine, determining the lateral offset of the center point of the additional turbulence intensity profile in the horizontal plane at each vertical height from the first longitudinal plane at various positions in the downwind direction of the wind turbine, where the lateral offset at the hub height of the wind turbine is 0;

[0013] Combining the lateral offsets of the center points of the additional turbulence intensity profiles in the horizontal planes at each vertical height at various positions in the downwind direction of the wind turbine, expanding the additional turbulence intensity two-dimensional model into an additional turbulence intensity three-dimensional model;

[0014] Combining the lateral offsets of the center points of the additional turbulence intensity profiles in the horizontal planes at each vertical height at various positions in the downwind direction of the wind turbine, constructing a ground effect correction function, and using the correction function to correct the additional turbulence intensity three-dimensional model to form an additional turbulence intensity calculation model for the wind turbine;

[0015] The first height range includes the vertical height range of the wind turbine; the multiple preset typical heights include the hub height of the wind turbine; the first longitudinal plane is a longitudinal plane passing through the center point of the wind turbine and parallel to the inflow wind direction at the hub height of the wind turbine.

[0016] The use of a double-peak Gaussian function to describe the additional turbulence intensity profile in the horizontal plane at the hub height of the wind turbine includes:

[0017]

[0018] In the formula, I + (x,r) is the additional turbulence intensity at a position x in the downwind direction of the wind turbine disk and at a distance r from the center point of the additional turbulence intensity profile; is the peak value of the additional turbulence intensity at the downstream x of the wind turbine rotor disk plane; is the double-peak Gaussian function used to describe the additional turbulence intensity at the downstream x of the wind turbine rotor disk plane, and σ I is its standard deviation;

[0019]

[0020] In the formula, D and C T are the rotor diameter and thrust coefficient of the wind turbine respectively; I is the turbulence intensity at the wind turbine;

[0021]

[0022] When :

[0023]

[0024] And when :

[0025] k 1 = 1, k 2 = 0

[0026] In the formula, k 1 and k 2 are weight coefficients; refers to the distance between the peak point and the center point of the additional turbulence intensity profile.

[0027] The gradually increasing distance between the peak point and the center point of the profile as it moves away from the wind turbine rotor disk plane includes:

[0028] Based on the analysis of the high-precision CFD simulation results of the additional turbulence intensity, in the near wake region close to the wind turbine rotor disk plane, affected by the tip vortices, the peak point of the additional turbulence intensity profile approximately appears at the blade tip, that is, there is And as the wake propagates downstream, because it continuously exchanges momentum with the ambient flow field, the peak point of the profile will gradually move away from the center point, and the distance between the two can be estimated by ;

[0029] Because the distribution of the additional turbulence intensity in the near wake region is actually very complex and cannot be simply described by the double-peak Gaussian function, so if is applied to the near wake region, a situation where it is less than 0.5D may occur, which is contrary to the aforementioned CFD simulation results;

[0030] To take into account the calculation accuracy of both the far and near wake regions simultaneously, the following formula is used to estimate

[0031]

[0032] In the formula, Denote the distance between the peak point of the additional turbulence intensity profile and its center point; σ I is the standard deviation of the additional turbulence intensity at the downwind x of the wind turbine disk; D and C T are the wind turbine diameter and thrust coefficient respectively; U is the turbulence intensity at the wind turbine location.

[0033] Determining the lateral offset of the center point of the additional turbulence intensity profile in the horizontal plane at each vertical height from the first longitudinal plane based on the relative wind direction angles at each vertical height within the vertical height range of the wind turbine, including:

[0034] According to the basic kinematic formula, the lateral offset U c (x,z):

[0035] I c (x,z) ≈ V(z) * t

[0036] In the formula, V(z) represents the lateral velocity of the incoming flow at the vertical height z, and t denotes the time required for the wind turbine wake to propagate to the downwind x behind the wind turbine disk. The calculation formula is:

[0037] t = x / U(z)

[0038] In the formula, U(z) represents the flow velocity of the incoming flow at the vertical height z;

[0039] From the above, it can be obtained that:

[0040]

[0041] In the formula, I c (x,z) is the distance between the center point of the additional turbulence intensity profile at the vertical height z and the downwind distance x from the wind turbine disk and the first longitudinal plane; θ′(z) is the relative wind direction angle of the incoming flow wind direction angle at the vertical height z of the wind turbine relative to the incoming flow wind direction angle at the hub height.

[0042] Expanding the two-dimensional model of the additional turbulence intensity into a three-dimensional model of the additional turbulence intensity by combining the lateral offsets of the center points of the additional turbulence intensity profiles in the horizontal planes at each vertical height, including:

[0043]

[0044] In the formula, r is the distance between any position coordinate point (x,y,z) in the wake cross-section at the downwind distance x from the wind turbine disk and the center axis of the wind turbine after being corrected by the lateral offset I c (x,z); I c (x,z) is the distance between the center point of the additional turbulence intensity profile at the vertical height z and the downwind distance x from the wind turbine disk and the first longitudinal plane; zhub is the hub height of the wind turbine.

[0045] Constructing a ground effect correction function by combining the lateral offsets of the central points of the additional turbulence intensity profiles in each vertical height horizontal plane at various locations downstream of the wind turbine, including:

[0046]

[0047] In the formula, I +mod (x, r) is the corrected value of the additional turbulence intensity at a position x downstream of the wind turbine rotor disk and at a distance r from the central point of the additional turbulence intensity profile; is the peak value of the additional turbulence intensity at a position x downstream of the wind turbine rotor disk; r is the distance between any position coordinate point (x, y, z) in the wake cross-section at a distance x downstream of the wind turbine and the central axis of the rotor after correction by the lateral offset I c (x, z); refers to the distance between the peak point and the central point of the additional turbulence intensity profile; α is the direction angle; z hub is the hub height of the wind turbine; I c (x, z) is the distance by which the central point of the additional turbulence intensity profile at a vertical height z and at a distance x downstream of the wind turbine deviates from the first longitudinal plane.

[0048] A device for constructing a calculation model of additional turbulence intensity of a wind turbine applicable to stable atmosphere, which is applicable to the stable atmosphere state, including:

[0049] A two-dimensional model construction module, which is used to describe the additional turbulence intensity profile in the horizontal plane of the wind turbine hub height by using a double-peak Gaussian function, and gradually increases the distance between the peak point and the central point of the profile as it moves away from the rotor disk, forming a two-dimensional model of additional turbulence intensity;

[0050] A relative angle calculation module, which is used to obtain the inflow wind direction angles at multiple preset typical heights within the first height range, and calculate the relative wind direction angles of the inflow wind direction angles at each preset typical height relative to the inflow wind direction angle at the wind turbine hub height;

[0051] A data fitting module, which is used to fit the relative wind direction angles at each preset typical height to obtain the relationship between the vertical height and the relative wind direction angle;

[0052] A wind direction angle determination module, which is used to determine the relative wind direction angles at each vertical height within the vertical height range of the rotor based on the relationship between the vertical height and the relative wind direction angle;

[0053] An offset calculation module, configured to determine the lateral offsets of the central points of the additional turbulence intensity profiles in the horizontal planes at each vertical height from the first longitudinal plane at various locations in the downwind direction of the wind turbine based on the relative wind direction angles at each vertical height within the vertical height range of the wind turbine rotor, wherein the lateral offset at the hub height of the wind turbine is 0;

[0054] A two-dimensional model expansion module, configured to expand the two-dimensional model of the additional turbulence intensity into a three-dimensional model of the additional turbulence intensity by combining the lateral offsets of the central points of the additional turbulence intensity profiles in the horizontal planes at each vertical height at various locations in the downwind direction of the wind turbine;

[0055] A ground effect correction module, configured to construct a ground effect correction function by combining the lateral offsets of the central points of the additional turbulence intensity profiles in the horizontal planes at each vertical height at various locations in the downwind direction of the wind turbine, and use the correction function to correct the three-dimensional model of the additional turbulence intensity to form a calculation model for the additional turbulence intensity of the wind turbine;

[0056] The first height range includes the vertical height range of the wind turbine rotor; the multiple preset typical heights include the hub height of the wind turbine; the first longitudinal plane is a longitudinal plane passing through the center point of the wind turbine rotor and parallel to the inflow wind direction at the hub height of the wind turbine.

[0057] A method for calculating the additional turbulence intensity of a wind turbine applicable to stable atmosphere, which is applicable to the stable atmosphere state and includes:

[0058] Obtain the wind turbine parameters and the basic data of the inflow wind, as well as the coordinate information of the point to be calculated, wherein the wind turbine parameters include the hub height, rotor diameter and thrust coefficient of the wind turbine; the basic data of the inflow wind includes the wind direction and turbulence intensity at multiple preset typical heights including the hub height of the wind turbine;

[0059] Based on the wind turbine parameters and the basic data of the inflow wind, adopt the construction method to construct a calculation model for the additional turbulence intensity;

[0060] Input the coordinate information of the point to be calculated into the calculation model for the additional turbulence intensity, and calculate the additional turbulence intensity of the point to be calculated.

[0061] A storage medium, on which a computer program executable by a processor is stored, and when the computer program is executed, the steps of the method for constructing the calculation model for the additional turbulence intensity of the wind turbine are implemented.

[0062] A device for constructing a calculation model for the additional turbulence intensity of a wind turbine, having a memory and a processor, and a computer program executable by the processor is stored on the memory, and when the computer program is executed, the steps of the method for constructing the calculation model for the additional turbulence intensity of the wind turbine are implemented.

[0063] A storage medium stores a computer program executable by a processor. When the computer program is executed, the steps of the method for calculating the additional turbulence intensity of a wind turbine are implemented.

[0064] A device for calculating the additional turbulence intensity of a wind turbine has a memory and a processor. The memory stores a computer program executable by the processor. When the computer program is executed, the steps of the method for calculating the additional turbulence intensity of a wind turbine are implemented.

[0065] The beneficial effects of the present invention are as follows:

[0066] Based on the inflow wind direction angles at multiple preset typical heights, the present invention determines the relative wind direction angles at each preset typical height relative to the inflow wind direction at the hub height of the wind turbine, and then fits the relationship between the vertical height and the relative wind direction angle, so as to determine the relative wind direction angles at each vertical height within the vertical height range of the wind turbine under a stable atmospheric state in a simple and fast manner.

[0067] Based on the relative wind direction angles at each vertical height, the present invention determines the lateral offset amounts of the center points of the additional turbulence intensity profiles in the horizontal planes at each vertical height caused by different wind directions at various positions downstream of the wind turbine deviating from the first longitudinal plane, and then constructs a three-dimensional model of the additional turbulence intensity and a ground effect correction function under a stable atmospheric state based on the lateral offset amounts, and forms a calculation model for the additional turbulence intensity of a wind turbine applicable to a stable atmosphere based on the three-dimensional model of the additional turbulence intensity and the ground effect correction function.

[0068] In the present invention, the additional turbulence intensity model under a neutral atmospheric state is made applicable to a stable atmospheric state by correcting the parameter r of the lateral offset amount.

[0069] The present invention combines the lateral offset amounts of the center points of the additional turbulence intensity profiles to construct a ground effect correction function, so as to realize the influence of the focusing ground effect and the wind direction vertical shear on the additional turbulence intensity in the area below the hub height of the wind turbine through the ground effect correction function.

[0070] The present invention comprehensively considers the influence of multiple key inflow characteristic quantities such as turbulence intensity and wind direction vertical shear that change with the atmospheric stability. By constructing the correlation between them and the evolution form of the additional turbulence intensity of the wind turbine, a calculation model for the additional turbulence intensity of the wind turbine is constructed. Compared with the existing models, the calculation accuracy of the additional turbulence intensity calculation model constructed by the present invention is significantly improved, and it can accurately simulate the change of the additional turbulence intensity with the downstream distance in the far wake area of the wind turbine, and capture the three-dimensional distribution asymmetry characteristics caused by the coupling influence of the ground effect and the strong wind direction vertical shear in a stable atmosphere.

[0071] The present invention increases the distance between the peak point and the center point of the profile gradually as it moves away from the wind turbine disk plane, so that the additional turbulence intensity calculation model takes into account the change in the position of the peak point caused by wake expansion.

[0072] The present invention adopts estimating the distance between the peak point and the center point of the additional turbulence intensity profile, which is in line with the CFD simulation results and takes into account the calculation accuracy in both the far and near wake regions. Description of the Drawings

[0073] Figure 1 It is a flow chart for constructing the additional turbulence intensity calculation model in the embodiment.

[0074] Figure 2 It is a schematic diagram of the derivation process of the analytical model for the additional turbulence intensity of a wind turbine under stable atmosphere in the embodiment.

[0075] Figure 3 It is a cloud map of the additional turbulence intensity at different downstream positions in the wake region of the NREL 5MW wind turbine in Example 1 of the embodiment.

[0076] Figure 4 It is the additional turbulence intensity profile at different downstream positions in the wake region of the NREL 5MW wind turbine in Example 1 of the embodiment, where (a) is the profile in the horizontal plane at hub height, and (b) is the profile in the mid-longitudinal plane passing through the center point of the wind turbine.

[0077] Figure 5 It is a cloud map of the additional turbulence intensity at different downstream positions in the wake region of the NREL 5MW wind turbine in Example 2 of the embodiment.

[0078] Figure 6 It is the additional turbulence intensity profile at different downstream positions in the wake region of the NREL 5MW wind turbine in Example 2 of the embodiment, where (a) is the profile in the horizontal plane at hub height, and (b) is the profile in the mid-longitudinal plane passing through the center point of the wind turbine.

[0079] Figure 7 It is a cloud map of the additional turbulence intensity at 6 times the wind turbine diameter behind the disk plane of the Vestas 2MW wind turbine in Example 3 of the embodiment, where (a) is the CFD simulation result and (b) is the model calculation result. Detailed Embodiment

[0080] For a better understanding of the technical solution of the present application, the embodiments of the present application will be described in detail below with reference to the accompanying drawings.

[0081] It should be clear that the described embodiments are only a part of the embodiments of the present application, rather than all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present application.

[0082] The terms used in the embodiments of the present application are only for the purpose of describing specific embodiments and are not intended to limit the present application. The singular forms "a", "the", and "said" used in the embodiments of the present application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise.

[0083] Embodiment 1: This embodiment is a method for constructing an additional turbulence intensity calculation model for a wind turbine applicable to a stable atmosphere, as Figure 1 shown. The construction method specifically includes the following steps:

[0084] S100. Use a double-peak Gaussian function to describe the additional turbulence intensity profile in the horizontal plane at the hub height of the wind turbine, and gradually increase the distance between the peak point and the center point of the profile as the distance from the wind turbine disk increases, forming a two-dimensional model of the additional turbulence intensity in the horizontal plane at the hub height.

[0085] In this embodiment, the position of the wind turbine is taken as the coordinate origin, the wind direction at its hub height is the positive x-axis direction, the direction perpendicular to the x-axis in the horizontal plane is the y-axis direction, and the vertical line passing through the center point of the wind turbine is the z-axis direction (vertically upward is the positive z-axis direction), and a right-handed coordinate system is established. In this coordinate system, the coordinates of the center point of the wind turbine disk are (0, 0, z hub ), where z hub is the hub height of the wind turbine.

[0086] During the actual operation of the wind turbine, in order to improve its own wind energy absorption efficiency, with the help of the yaw control system, the wind turbine disk is always approximately perpendicular to the incoming wind direction at the center point of the wind turbine disk, that is, the central axis of the wind turbine is parallel to the incoming wind direction at the hub height. In this example, the model derivation also follows this engineering practice that the wind turbine disk is perpendicular to the incoming wind direction at the center point.

[0087] In this embodiment, a double-peak Gaussian function is used to describe the additional turbulence intensity profile in the horizontal plane at the hub height of the wind turbine (see Figure 2 part (a)), and the calculation formula is:

[0088]

[0089] In the formula, I +(x, r) is an additional turbulence intensity calculation formula constructed based on x and r, representing the additional turbulence intensity at a position x downstream of the wind turbine rotor plane and at a distance r from the center point of the additional turbulence intensity profile; x is the distance of the position downstream of the wind turbine rotor plane relative to the wind turbine rotor plane; is the peak value of the additional turbulence intensity at x downstream of the wind turbine rotor plane; is the double-peak Gaussian function used to describe the additional turbulence intensity at x downstream of the wind turbine rotor plane, σ I is the standard deviation of the additional turbulence intensity at x downstream.

[0090] In Equation (1), r refers to the distance of the point (x, y) at a distance x downstream of the wind turbine rotor plane in the horizontal plane of the wind turbine hub height relative to the center point of the additional turbulence intensity profile at this location (the center point of the additional turbulence intensity profile in the horizontal plane of the wind turbine hub height is located on the wind turbine central axis). As mentioned above, since the orientation of the wind turbine rotor plane is always approximately perpendicular to the inflow wind direction at the hub height (at the center point of the wind turbine rotor plane), in the horizontal plane of the wind turbine hub height, the center points of the additional turbulence intensity profiles at different downstream distances behind the wind turbine rotor plane are along the wind turbine central axis. Therefore, the calculation formula for r in the horizontal plane of the wind turbine hub height is:

[0091]

[0092] According to the data fitting results of Ishihara et al., in Equation (1), and σ I are calculated by the following formula:

[0093]

[0094] In the formula, D and C T are the wind turbine rotor diameter and thrust coefficient respectively; I is the turbulence intensity at the wind turbine.

[0095] In a wind farm, for the upwind wind turbine that is not affected by the wake interference of other wind turbines, the value of I can refer to the turbulence intensity in the inflow, such as the turbulence intensity at the hub height or the mean value of the turbulence intensity in the wind turbine rotor plane; while for the downwind wind turbine, in addition to the turbulence intensity in the inflow, the value of I needs to further consider the influence of the additional turbulence intensity generated by the operation of the upwind wind turbine.

[0096] In Equation (1), The calculation formula is:

[0097]

[0098] In the formula, k 1 and k 2 are weight coefficients; refers to the distance between the peak point and the center point of the additional turbulence intensity profile.

[0099] In order to keep the calculation results at the peak point of the additional turbulence intensity profile continuous, in this embodiment, k 1 and k 2 are calculated as follows:

[0100] When :

[0101]

[0102] And when :

[0103] k 1 = 1, k 2 = 0 (8)

[0104] In the Ishihara model, it is assumed that is 0.5 times the wind turbine diameter, expressed as Actually, based on the analysis of the high-precision CFD simulation results of the additional turbulence intensity, in the near wake region close to the wind turbine disk plane, affected by the tip vortex, the peak point of the additional turbulence intensity profile approximately appears at the blade tip, that is, there is And as the wake propagates downstream, because it continuously exchanges momentum with the ambient flow field, the peak point of the profile will gradually move away from the center point, which is called the "wake expansion characteristic". The distance between the peak point of the additional turbulence intensity profile and its center point can be estimated by estimated.

[0105] Since the distribution of the additional turbulence intensity in the near wake region is actually very complex and cannot be simply described by a double-peak Gaussian function, if is applied to the near wake region, a situation where it is less than 0.5D may occur, which is contrary to the aforementioned CFD simulation results. In view of this, in order to simultaneously take into account the calculation accuracy of both the far and near wake regions, in this embodiment, the following formula is used to estimate

[0106]

[0107] S200. Obtain the inflow wind direction angles at multiple preset typical heights within the first height range (including the vertical height range of the wind turbine), and calculate the relative wind direction angles of the inflow wind direction angles at each preset typical height with respect to the inflow wind direction angle at the hub height of the wind turbine.

[0108] In this embodiment, the multiple preset typical heights at least include the hub height z hub of the wind turbine, the vertical height z 1 where the tip of the wind turbine disk plane is located, and the vertical height z 2 where the tip of the wind turbine disk plane is located.

[0109] z1 = z hub + D / 2

[0110] z 2 = z hub - D / 2

[0111] In this example, the calculation formula for the relative wind direction angle is as follows:

[0112] θ′(z) = θ(z) - θ(z hub )

[0113] where θ′(z) is the relative wind direction angle at the vertical height z; θ(z) is the incoming flow wind direction angle at the vertical height z; θ(z hub ) is the incoming flow wind direction angle at the wind turbine hub height z hub .

[0114] S300. Based on the calculation results of step S200, fit the relative wind direction angles at each preset typical height to obtain the relationship between the vertical height and the relative wind direction angle.

[0115] Multiple sets of measured and CFD simulation data show that in a stable atmospheric state, the incoming flow wind direction changes approximately linearly with the increase of the vertical height. Therefore, in this embodiment, a linear fitting method is used to process the relative wind direction angles at multiple preset typical heights obtained in step S200 to obtain the linear relationship between the vertical height and the relative wind direction angle. In this example, it is necessary to ensure that the relative wind direction angle at the wind turbine hub height z hub is 0.

[0116] S400. Based on the relationship between the vertical height and the relative wind direction angle obtained in step S300, determine the relative wind direction angles at each vertical height within the vertical height range of the wind turbine rotor.

[0117] S500. Based on the relative wind direction angles at each vertical height within the vertical height range of the wind turbine rotor determined in step S400, determine the lateral offset of the center point of the additional turbulence intensity profile in the horizontal plane of each vertical height from the first longitudinal plane at each location downstream of the wind turbine.

[0118] Affected by the strong vertical wind shear in the stable atmospheric inflow, the additional turbulence intensity profile of the wind turbine is not symmetric with respect to the vertical axis (i.e., the z-axis) passing through the center point of the wind turbine, as in the neutral atmosphere, but shows an obvious tilt, as shown in Figure 2 part (b). From the perspective of mathematical modeling, this actually corresponds to the center point of the additional turbulence intensity profile at each location downstream of the wind turbine disk in the horizontal plane of different vertical heights deviating from the xoz plane (the longitudinal plane passing through the center point of the wind turbine and parallel to the incoming flow wind direction at the wind turbine hub height, named the first longitudinal plane). In Figure 2 part (b), this lateral offset is represented by I cIt is represented by (x, z).

[0119] In wind power engineering practice, the center point of the wind turbine rotor disk is always approximately perpendicular to the incoming wind direction at the hub height. This means that in the horizontal plane of the hub height, there is:

[0120] I c (x, z) = 0 (10)

[0121] At other vertical heights z, due to the relative wind direction angle θ′(z) of the wind direction angle θ(z) at height z relative to the wind direction angle θ(z hub at height z hub ), which is an important external driving factor causing the profile to tilt, the construction of the functional relationship between I c (x, z) and the relative wind direction angle θ′(z) is the key point of modeling.

[0122] According to the basic kinematic formula, I c (x, z) can be estimated by the following formula:

[0123] I c (x, z) ≈ V(z) * t (11)

[0124] In the formula, V(z) represents the lateral (y - axis direction) velocity of the incoming wind at the vertical height z, and t represents the time required for the wind turbine wake to propagate to the downstream x position of the wind turbine rotor disk. The calculation formula is:

[0125] t = x / U(z) (12)

[0126] In the formula, U(z) represents the flow direction (x - axis direction, that is, the direction corresponding to θ(z hub )) velocity of the incoming wind at the vertical height z.

[0127] By combining Equation (11) and Equation (12), we can obtain:

[0128]

[0129] S600. Combining the lateral offsets of the center points of the additional turbulence intensity profile in each vertical - height horizontal plane at various downstream positions of the wind turbine, the two - dimensional model of the additional turbulence intensity is extended to a three - dimensional model of the additional turbulence intensity.

[0130] Equation (1) is the two - dimensional model of the additional turbulence intensity. In this example, r in Equation (1) is adjusted by the following formula to extend the two - dimensional model of the additional turbulence intensity to a three - dimensional model;

[0131]

[0132] Affected by the strong vertical wind shear in the stable atmospheric inflow, the additional turbulence intensity profile of the wind turbine will show an obvious inclination. Therefore, in this application, the r is corrected by the lateral offset, and the corrected r can be calculated by the following formula:

[0133]

[0134] In Equation (15), r is the distance between any position coordinate point (x, y, z) in the wake cross-section at the downwind distance x from the wind turbine rotor disk and the center axis of the wind turbine after being corrected by the lateral offset I c (x, z).

[0135] In the horizontal plane of the hub height, z = z hub , and according to Equation (10), it can be known that I c (x, z) = 0. Substituting these two into Equation (15), is the same as Equation (2).

[0136] The vertical wind shear in the neutral atmosphere is very small, that is, the wind direction angles at different vertical heights z are approximately the same as those at the hub height z hub . In this case, θ′(z)≈0 and I c (x, z)≈0 respectively. Substituting the two into Equation (15) gives which is the same as the model calculation formula in the neutral atmosphere derived by Ishihara et al.

[0137] S700. Combining the lateral offsets of the central points of the additional turbulence intensity profiles in the horizontal planes of each vertical height at various downwind positions of the wind turbine, a ground effect correction function is constructed, and the three-dimensional model of the additional turbulence intensity is corrected by using the correction function to form a calculation model of the additional turbulence intensity of the wind turbine.

[0138] Affected by the ground effect, the additional turbulence intensity in the area below the hub height of the wind turbine decreases significantly, and in the stable atmosphere, it will deviate from the xoz plane to different degrees following the inflow wind direction at different vertical heights z.

[0139] In view of the above three-dimensional distribution characteristics, the ground effect correction function I +mod (x, r) is given in this embodiment. On the basis of Equation (1), the calculation formula of the additional turbulence intensity considering three-dimensional correction is:

[0140]

[0141] The characteristics of the correction function I +mod (x, r) in this embodiment are as follows:

[0142] (1) Above the hub height of the wind turbine, the function value is fixed at 0;

[0143] (2) Below the hub height of the wind turbine, the peak value of the function is taken Considering the influence of the "wake expansion characteristic" at the same time, it is assumed that the radial distance between the peak point and the central axis of the wind wheel is For the area between the peak point and the central axis of the wind wheel, as the radial distance decreases, the function gradually transitions to 0 in the form of the sine value of the azimuth angle. In the outer area of the peak point, it is considered that its radial change still satisfies the Gaussian distribution.

[0144] In this example, the ground effect correction function I +mod The specific calculation formula of (x, r) is:

[0145]

[0146] Referring to the description of feature (2), the calculation formula of parameter P in formula (17) is:

[0147]

[0148] In formula (17), α is the azimuth angle, its value along the positive direction of the y-axis is 0, and its value along the negative direction of the y-axis is -π. Further considering the influence of the strong vertical wind shear in the stable atmosphere on the evolution form of the additional turbulence intensity, α can be calculated by the following formula:

[0149]

[0150] In this embodiment, the lateral offset I based on the center point of the additional turbulence intensity profile c (x, z) determines the azimuth angle α, and based on the azimuth angle α, the ground effect correction function I +mod (x, r) is determined, so as to realize the influence of the focusing ground effect and the vertical wind shear on the additional turbulence intensity.

[0151] In step S700 of this embodiment, r is the distance between any position coordinate point (x, y, z) in the wake cross-section at a distance x from the wind wheel disk in the downwind direction of the wind turbine and the central axis of the wind wheel after being corrected by the lateral offset I c (x, z), and is calculated by formula (15) to correct the deviation of the ground effect influence caused by different inflow wind directions at different vertical heights.

[0152] Embodiment 2: This embodiment is a device for constructing a calculation model of the additional turbulence intensity of a wind turbine applicable to a stable atmosphere. This device is applicable to the stable atmosphere state and includes: a two-dimensional model construction module, a relative angle calculation module, a data fitting module, a wind direction angle determination module, an offset calculation module, a two-dimensional model expansion module, a ground effect correction module, etc.

[0153] In this example, the two-dimensional model construction module is used to describe the additional turbulence intensity profile in the horizontal plane of the wind turbine hub height using a bimodal Gaussian function, and gradually increase the distance between the peak point and the center point of the profile as it moves away from the rotor disk plane, forming a two-dimensional model of the additional turbulence intensity.

[0154] In this embodiment, the relative angle calculation module is used to obtain the inflow wind direction angles at multiple preset typical heights within the first height range, and calculate the relative wind direction angles of the inflow wind direction angles at each preset typical height relative to the inflow wind direction angle at the wind turbine hub height.

[0155] The data fitting module is used to fit the relative wind direction angles at each preset typical height to obtain the relationship between the vertical height and the relative wind direction angle.

[0156] In this example, the wind direction angle determination module is used to determine the relative wind direction angles at each vertical height within the vertical height range of the rotor based on the relationship between the vertical height and the relative wind direction angle.

[0157] The offset calculation module is used to determine the lateral offset of the center point of the additional turbulence intensity profile in the horizontal plane of each vertical height from the first longitudinal plane at various positions in the downwind direction of the wind turbine based on the relative wind direction angles at each vertical height within the vertical height range of the rotor, where the lateral offset at the wind turbine hub height is 0.

[0158] In this embodiment, the two-dimensional model expansion module is used to expand the two-dimensional model of the additional turbulence intensity into a three-dimensional model of the additional turbulence intensity by combining the lateral offsets of the center points of the additional turbulence intensity profiles in the horizontal planes of each vertical height at various positions in the downwind direction of the wind turbine.

[0159] In this example, the ground effect correction module is used to construct a ground effect correction function by combining the lateral offsets of the center points of the additional turbulence intensity profiles in the horizontal planes of each vertical height at various positions in the downwind direction of the wind turbine, and use the correction function to correct the three-dimensional model of the additional turbulence intensity to form a calculation model of the additional turbulence intensity of the wind turbine.

[0160] In this embodiment, the first height range includes the vertical height range of the rotor, the multiple preset typical heights include the wind turbine hub height, and the first longitudinal plane is a longitudinal plane passing through the center point of the rotor and parallel to the inflow wind direction at the wind turbine hub height.

[0161] Embodiment 3: This embodiment is a storage medium on which a computer program executable by a processor is stored. When the computer program is executed, the steps of the method for constructing the calculation model of the additional turbulence intensity of the wind turbine in Embodiment 1 are implemented.

[0162] Embodiment 4: This embodiment is a device for constructing a calculation model of the additional turbulence intensity of a wind turbine, which has a memory and a processor. A computer program that can be executed by the processor is stored on the memory. When this computer program is executed, the steps of the method for constructing the calculation model of the additional turbulence intensity of the wind turbine in Embodiment 1 are implemented.

[0163] Embodiment 5: This embodiment is a method for calculating the additional turbulence intensity of a wind turbine applicable to stable atmosphere, which specifically includes the following steps:

[0164] Step I: Obtain the wind turbine parameters and the basic data of the incoming flow wind, as well as the xyz three-axis coordinate information of the point to be calculated. Among them, obtaining the wind turbine parameters mainly includes the hub height z of the wind turbine hub , the rotor diameter D, and the thrust coefficient C T ; the basic data of the incoming flow wind includes the wind direction angle θ(z) and the turbulence intensity I at multiple preset typical heights including the hub height of the wind turbine.

[0165] Step II: Based on the wind turbine parameters and the basic data of the incoming flow wind, use the method for constructing the calculation model of the additional turbulence intensity of the wind turbine applicable to stable atmosphere in Embodiment 1 to construct an additional turbulence intensity calculation model.

[0166] Step III: Input the coordinate information of the point to be calculated into the additional turbulence intensity calculation model, and calculate the additional turbulence intensity of the point to be calculated.

[0167] The effectiveness and reliability of this embodiment are illustrated by the following three specific examples:

[0168] Both Example 1 and Example 2 take the NREL 5MW wind turbine as the research object, and its rotor diameter and hub height are 126m and 90m respectively. In these two examples, the wind turbine operates under stable atmosphere, the turbulence intensity at its hub height is about 0.046, and the wind direction angle difference between the upper and lower end points of the rotor disk is about 8.6°. The difference between the two examples is that in Example 1, the wind turbine operates at the optimal tip speed ratio, and the corresponding thrust coefficient is about 0.72, while in Example 2, by adjusting the wind turbine speed, its tip speed ratio is fixed at 5.77, and the corresponding thrust coefficient is about 0.57.

[0169] Taking the high-precision CFD simulation results as the reference benchmark, Figure 3 and Figure 5 successively present the additional turbulence intensity contour maps at 4, 6, and 8 times the rotor diameter behind the rotor disk of the wind turbine in the above two examples. And to more clearly quantify the accuracy differences of different model methods, two representative cross-sections, namely the horizontal plane at the hub height of the wind turbine and the mid-longitudinal plane passing through the center point of the rotor, are selected, and the calculation results of the additional turbulence intensity profiles are compared in Figure 4 and Figure 6 .

[0170] Figures 3 - 5 In the legend, CFD, New, Ishihara, and IEC represent the CFD simulation results, the additional turbulence intensity calculation model of the wind turbine proposed in this embodiment, and the calculation results of the Ishihara model and the IEC model commonly used in the current academic and engineering circles, respectively. As can be seen from the figure, overall, under the two different operating states of the wind turbine described in Example 1 and Example 2, the additional turbulence intensity calculation model of the wind turbine proposed in this embodiment can better capture the change of the additional turbulence intensity of the wind turbine with the downstream distance under stable atmosphere, accurately simulate the asymmetric profile caused by the strong vertical wind shear in the inflow, and is in good agreement with the CFD simulation results. The calculation accuracy is significantly improved compared with the other two existing model methods.

[0171] To test the robustness of the new model of the present invention, Example 3 uses the Vestas 2MW wind turbine as the research object, whose rotor diameter and hub height are 80m and 70m respectively. Still taking the CFD simulation result as the reference benchmark, the inflow turbulence intensity at the hub height is about 0.05, and the wind direction angle difference between the upper and lower endpoints of the blade is about 10°.

[0172] Under the above wind conditions, Figure 7 The turbulence intensity cloud map at 6 times the rotor diameter behind the wind turbine disk is shown. By comparison, the deviation between the IEC model and the CFD simulation result is the largest. In contrast, the calculation result of the additional turbulence intensity calculation model of the wind turbine proposed in this embodiment has the highest degree of agreement with the CFD cloud map. Since the Ishihara model only simply processes the ground effect, it cannot accurately describe the additional turbulence intensity in the area below the hub height of the wind turbine. Even at a distance of about 1 rotor diameter from the ground and the center axis of the wind turbine, an incorrect correction increment appears. More importantly, due to ignoring the influence of the vertical wind shear, the turbulence intensity calculated by it is approximately symmetrically distributed about the center axis of the wind turbine, which seriously deviates from the CFD simulation result.

[0173] Example 6: This example is a storage medium on which a computer program executable by a processor is stored. When the computer program is executed, the steps of the method for calculating the additional turbulence intensity of the wind turbine in Example 5 are implemented.

[0174] Example 7: This example is a device for calculating the additional turbulence intensity of a wind turbine, which has a memory and a processor. A computer program executable by the processor is stored on the memory. When the computer program is executed, the steps of the method for calculating the additional turbulence intensity of the wind turbine in Example 5 are implemented.

Claims

1. A method for constructing a calculation model for additional turbulence intensity of a wind turbine suitable for a stable atmosphere, characterized in that: The method is applicable to stable atmospheric conditions, including: A double-peaked Gaussian function is used to describe the additional turbulence intensity profile in the horizontal plane at the hub height of the wind turbine, and the distance between the peak point of the profile and the center point of the profile is gradually increased as it moves away from the rotor disk surface, forming a two-dimensional model of additional turbulence intensity. Obtaining inflow wind direction angles at a plurality of preset typical heights within the first height range, and calculating the relative wind direction angle of the inflow wind direction angle at each preset typical height relative to the inflow wind direction angle at the height of the wind turbine hub; Fitting the relative wind direction angle at each preset typical height to obtain the relationship between the vertical height and the relative wind direction angle; Based on the relationship between the vertical height and the relative wind direction angle, the relative wind direction angle at each vertical height within the vertical height range of the wind rotor is determined; Based on the relative wind direction angle at each vertical height within the vertical height range of the wind rotor, determine the lateral offset of the center point of the additional turbulence intensity profile in the horizontal plane at each vertical height from the first longitudinal plane at each location downwind of the wind turbine, where the lateral offset at the height of the wind turbine hub is 0; Combined with the lateral displacement of the center point of the additional turbulence intensity profile in each vertical height horizontal plane at each location downwind of the wind turbine, the additional turbulence intensity two-dimensional model is expanded into an additional turbulence intensity three-dimensional model. Combined with the lateral offset of the center point of the additional turbulence intensity profile in each vertical height horizontal plane at each location downwind of the wind turbine, a ground effect correction function is constructed, and the additional turbulence intensity three-dimensional model is corrected using the correction function to form a calculation model for the additional turbulence intensity of the wind turbine. The first height range includes the vertical height range of the wind rotor; the multiple preset typical heights include the wind turbine hub height; the first longitudinal plane is a longitudinal plane passing through the center point of the wind rotor and parallel to the inflow wind direction at the wind turbine hub height; The double-peaked Gaussian function is used to describe the additional turbulence intensity profile in the horizontal plane at the wind turbine hub height, including: In the formula, I + (x,r) is the additional turbulence intensity at the position of x downwind from the wind turbine rotor surface and at a distance r from the center point of the additional turbulence intensity profile; is the additional turbulence intensity peak value at the wind direction x below the wind turbine rotor surface; is a double-peaked Gaussian function used to describe the additional turbulence intensity at the wind direction x below the wind turbine rotor surface, σ I is its standard deviation; In the formula, D and C T are the rotor diameter and thrust coefficient of the wind turbine respectively; I is the turbulence intensity at the wind turbine; when hour: When hour: k1=1,k2=0 In the formula, k1 and k2 are weight coefficients; Refers to the distance between the peak point of the additional turbulence intensity profile and its center point; The step of gradually increasing the distance between the peak point of the profile and the center point of the profile as the distance from the wind wheel disk surface increases, comprises: Based on the analysis of the high-precision CFD simulation results of the additional turbulence intensity, in the near wake area close to the wind rotor disk, affected by the blade tip vortex, the peak point of the additional turbulence intensity profile does appear approximately at the blade tip, that is, As the wake propagates downstream, it continuously exchanges momentum with the ambient flow field, and the peak point of the profile gradually moves away from the center point. The distance between the two can be expressed as Estimate; Since the distribution of additional turbulence intensity in the near wake region is actually very complex and cannot be simply described by a double-peaked Gaussian function, When applied to the near-wake region, a situation of less than 0.5D may occur, which is contrary to the aforementioned CFD simulation results; In order to take into account the calculation accuracy of both the far and near wake regions, the following formula is used to estimate : In the formula, Refers to the distance between the peak point of the additional turbulence intensity profile and its center point; σ I is the standard deviation of the additional turbulence intensity at the wind direction x below the rotor surface; D and C T are the rotor diameter and thrust coefficient of the wind turbine respectively; I is the turbulence intensity at the wind turbine; The additional turbulence intensity two-dimensional model is expanded into an additional turbulence intensity three-dimensional model by combining the lateral offset of the center point of the additional turbulence intensity profile in each vertical height horizontal plane at each location downwind of the wind turbine, including: Where r is the lateral offset I between the coordinate point (x, y, z) at any position in the wake cross section at a distance x from the rotor disk surface downwind of the wind turbine and the central axis of the rotor c (x),z) Corrected distance; I c (x,z) is the distance from the center point of the additional turbulence intensity profile at the vertical height z and the distance from the rotor disk x to the first longitudinal plane downwind of the wind turbine; z hub is the wind turbine hub height; The ground effect correction function is constructed by combining the lateral offset of the center point of the additional turbulence intensity profile in each vertical height horizontal plane at each location downwind of the wind turbine, including: In the formula, I +mod (x,r) is the additional turbulence intensity correction value at the position of the wind turbine rotor disk at the downwind direction x and at a distance r from the center point of the additional turbulence intensity profile; is the additional turbulence intensity peak value at x downwind from the wind turbine rotor surface; r is the lateral offset I between the coordinate point (x, y, z) at any position in the wake cross section at x downwind from the wind turbine rotor surface and the central axis of the wind rotor. c (x,z) Corrected distance; refers to the distance between the peak point of the additional turbulence intensity profile and its center point; α is the direction angle; z hub is the wind turbine hub height; I c (x,z) is the distance from the center point of the additional turbulence intensity profile at position x on the rotor disk surface at a vertical height z and downwind of the wind turbine, which deviates from the first longitudinal plane.

2. The method for constructing a wind turbine additional turbulence intensity calculation model applicable to a stable atmosphere according to claim 1, characterized in that: The method of determining the lateral displacement of the center point of the additional turbulence intensity profile in the horizontal plane at each vertical height from the first longitudinal plane at each location downwind of the wind turbine based on the relative wind direction angle at each vertical height within the vertical height range of the wind rotor comprises: According to the basic kinematics formula, the lateral offset I can be estimated by the following formula: c (x,z): I c (x,z)≈V(z)*t Where V(z) represents the lateral velocity of the inflow wind at the vertical height z, and t refers to the time required for the wind turbine wake to propagate to the point x behind the wind rotor. The calculation formula is: t=x / U(z) Where U(z) represents the streamwise velocity of the inflow wind at the vertical height z; From the above, we can get: Where θ'(z) is the relative wind direction angle of the inflow wind angle at the vertical height z of the wind turbine to the inflow wind direction angle at the hub height.

3. A device for constructing a calculation model of additional turbulence intensity of a wind turbine suitable for a stable atmosphere, characterized in that: The device is suitable for stabilizing atmospheric conditions and includes: A two-dimensional model building module is used to describe the additional turbulence intensity profile in the horizontal plane at the hub height of the wind turbine using a bimodal Gaussian function, and gradually increase the distance between the peak point of the profile and the center point of the profile as it moves away from the wind rotor disk surface, thereby forming a two-dimensional model of additional turbulence intensity; A relative angle calculation module, used to obtain the inflow wind direction angles at multiple preset typical heights within the first height range, and calculate the relative wind direction angles of the inflow wind direction angles at each preset typical height relative to the inflow wind direction angle at the wind turbine hub height; A data fitting module is used to fit the relative wind direction angle at each preset typical height to obtain the relationship between the vertical height and the relative wind direction angle; A wind direction angle determination module, used to determine the relative wind direction angle at each vertical height within the vertical height range of the wind rotor based on the relationship between the vertical height and the relative wind direction angle; An offset calculation module is used to determine the lateral offset of the center point of the additional turbulence intensity profile in the horizontal plane at each vertical height from the first longitudinal plane at each location downwind of the wind turbine based on the relative wind direction angle at each vertical height within the vertical height range of the wind rotor, wherein the lateral offset at the height of the wind turbine hub is 0; A two-dimensional model expansion module is used to expand the two-dimensional model of additional turbulence intensity into a three-dimensional model of additional turbulence intensity by combining the lateral offset of the center point of the additional turbulence intensity profile at each vertical height level at each location downwind of the wind turbine; The ground effect correction module is used to construct a ground effect correction function by combining the lateral offset of the center point of the additional turbulence intensity profile at each vertical height level at each location downwind of the wind turbine, and use the correction function to correct the additional turbulence intensity three-dimensional model to form a wind turbine additional turbulence intensity calculation model; The first height range includes the vertical height range of the wind rotor; the multiple preset typical heights include the wind turbine hub height; the first longitudinal plane is a longitudinal plane passing through the center point of the wind rotor and parallel to the inflow wind direction at the wind turbine hub height; The double-peaked Gaussian function is used to describe the additional turbulence intensity profile in the horizontal plane at the wind turbine hub height, including: In the formula, I + (x,r) is the additional turbulence intensity at the position of x downwind from the wind turbine rotor surface and at a distance r from the center point of the additional turbulence intensity profile; is the additional turbulence intensity peak value at the wind direction x below the wind turbine rotor surface; is a double-peaked Gaussian function used to describe the additional turbulence intensity at the wind direction x below the wind turbine rotor surface, σ I is its standard deviation; In the formula, D and C T are the rotor diameter and thrust coefficient of the wind turbine respectively; I is the turbulence intensity at the wind turbine; when hour: When hour: k1=1,k2=0 In the formula, k1 and k2 are weight coefficients; Refers to the distance between the peak point of the additional turbulence intensity profile and its center point; The step of gradually increasing the distance between the peak point of the profile and the center point of the profile as the distance from the wind wheel disk surface increases, comprises: Based on the analysis of the high-precision CFD simulation results of the additional turbulence intensity, in the near wake area close to the wind rotor disk, affected by the blade tip vortex, the peak point of the additional turbulence intensity profile does appear approximately at the blade tip, that is, As the wake propagates downstream, it continuously exchanges momentum with the ambient flow field, and the peak point of the profile gradually moves away from the center point. The distance between the two can be expressed as Estimate; Since the distribution of additional turbulence intensity in the near wake region is actually very complex and cannot be simply described by a double-peaked Gaussian function, When applied to the near-wake region, a situation of less than 0.5D may occur, which is contrary to the aforementioned CFD simulation results; In order to take into account the calculation accuracy of both the far and near wake regions, the following formula is used to estimate : In the formula, Refers to the distance between the peak point of the additional turbulence intensity profile and its center point; σ I is the standard deviation of the additional turbulence intensity at the wind direction x below the rotor surface; D and C T are the rotor diameter and thrust coefficient of the wind turbine respectively; i is the turbulence intensity at the wind turbine; The additional turbulence intensity two-dimensional model is expanded into an additional turbulence intensity three-dimensional model by combining the lateral offset of the center point of the additional turbulence intensity profile in each vertical height horizontal plane at each location downwind of the wind turbine, including: Where r is the lateral offset I between the coordinate point (x, y, z) at any position in the wake cross section at a distance x from the rotor disk surface downwind of the wind turbine and the central axis of the rotor c (x,z) Corrected distance; I c (x,z) is the distance from the center point of the additional turbulence intensity profile at the vertical height z and the distance from the rotor disk x to the first longitudinal plane downwind of the wind turbine; z hub is the wind turbine hub height; The ground effect correction function is constructed by combining the lateral offset of the center point of the additional turbulence intensity profile in each vertical height horizontal plane at each location downwind of the wind turbine, including: In the formula, I +mod (x,r) is the additional turbulence intensity correction value at the position of the wind turbine rotor disk at the downwind direction x and at a distance r from the center point of the additional turbulence intensity profile; is the additional turbulence intensity peak value at x downwind from the wind turbine rotor surface; r is the lateral offset I between the coordinate point (x, y, z) at any position in the wake cross section at x downwind from the wind turbine rotor surface and the central axis of the wind rotor. c (x,z) Corrected distance; refers to the distance between the peak point of the additional turbulence intensity profile and its center point; α is the direction angle; z hub is the wind turbine hub height; I c (x,z) is the distance from the center point of the additional turbulence intensity profile at position x on the rotor disk surface at a vertical height z and downwind of the wind turbine, which deviates from the first longitudinal plane.

4. A method for calculating the additional turbulence intensity of a wind turbine in a stable atmosphere, characterized in that: The method is applicable to stable atmospheric conditions, including: Obtain wind turbine parameters and basic inflow wind data, as well as coordinate information of the points to be calculated, wherein wind turbine parameters include wind turbine hub height, wind rotor diameter, and thrust coefficient; basic inflow wind data include wind direction and turbulence intensity at multiple preset typical heights including wind turbine hub height; Based on wind turbine parameters and inflow wind basic data, an additional turbulence intensity calculation model is constructed using the construction method described in any one of claims 1 to 2; The coordinate information of the point to be calculated is input into the additional turbulence intensity calculation model to calculate the additional turbulence intensity of the point to be calculated.

5. A storage medium having stored thereon a computer program executable by a processor, characterized in that: When the computer program is executed, the steps of the method for constructing a wind turbine additional turbulence intensity calculation model as described in any one of claims 1 to 2 are implemented.

6. A device for constructing a wind turbine additional turbulence intensity calculation model, comprising a memory and a processor, wherein the memory stores a computer program executable by the processor, characterized in that: When the computer program is executed, the steps of the method for constructing a wind turbine additional turbulence intensity calculation model as described in any one of claims 1 to 2 are implemented.

7. A storage medium having stored thereon a computer program executable by a processor, characterized in that: When the computer program is executed, the steps of the method for calculating the additional turbulence intensity of a wind turbine according to claim 4 are implemented.

8. A wind turbine additional turbulence intensity calculation device, comprising a memory and a processor, wherein the memory stores a computer program executable by the processor, characterized in that: When the computer program is executed, the steps of the method for calculating the additional turbulence intensity of a wind turbine according to claim 4 are implemented.

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