Inflow angle determination method and device, storage medium and electronic device

Abstract

The invention discloses an inflow angle determination method and device, a storage medium and an electronic device.The method comprises the steps that the local tip speed ratio of a blade is determined according to the incoming flow wind speed and the running rotating speed of the blade; determining a magnitude relationship between the local tip speed ratio and a preset tip speed ratio; under the condition that the size relation indicates that the local tip speed ratio is larger than or equal to the preset tip speed ratio, the inflow angle of the blade element of the blade is determined according to the local tip speed ratio; and under the condition that the size relation indicates that the local tip speed ratio is smaller than the preset tip speed ratio, the inflow angle of the blade element of the blade is determined according to the lift line slope of the blade and the local tip speed ratio. The problem that the calculation time for determining the inflow angle of the leaf element is long or the calculation result is inaccurate in the related technology is solved.

Description

Technical Field

[0001] The present application relates to the field of dynamics, and in particular, to a method and device for determining an inflow angle, a storage medium, and an electronic device. Background Art

[0002] In the study of wind turbine aerodynamics, the commonly used method for solving aerodynamic characteristics is to calculate the induced velocity of the wind rotor position by combining momentum with blade element theory, which is the commonly used "blade element-momentum theory" (BEM theory for short).

[0003] The core of the blade element-momentum theory method is to iteratively solve the axial and circumferential induction factors, and then find the inflow angle of each blade element, and finally calculate the wind energy conversion efficiency and load analysis. In the iterative calculation process, due to the nonlinearity of the aerodynamic characteristics of the airfoil and the nonlinearity of the calculation formula, the induction factor may not converge, so the calculation time is infinitely extended. In order to avoid non-convergence and affect the calculation time, the number of iterations is generally limited in the calculation program. However, this will cause calculation distortion, and in severe cases, it will lead to under-conservative or over-conservative blade design, resulting in blade failure or too low power generation.

[0004] With regard to the problem in the related art that the calculation time for determining the inflow angle of a blade element is long or the calculation result is inaccurate, no effective solution has been proposed yet.

[0005] Therefore, it is necessary to improve the related technology to overcome the above-mentioned defects in the related technology. Summary of the invention

[0006] The embodiments of the present application provide a method and device for determining an inflow angle, a storage medium, and an electronic device, so as to at least solve the problem in the related art that the calculation time for determining the inflow angle of a blade element is long or the calculation result is inaccurate.

[0007] According to one aspect of an embodiment of the present application, a method for determining an inflow angle is provided, comprising: determining a local tip speed ratio of the blade based on an incoming wind speed and an operating speed of the blade; determining a magnitude relationship between the local tip speed ratio and a preset tip speed ratio; determining an inflow angle of a blade element of the blade based on the local tip speed ratio when the magnitude relationship indicates that the local tip speed ratio is greater than or equal to the preset tip speed ratio; determining an inflow angle of the blade element of the blade based on a lift line slope of the blade and the local tip speed ratio when the magnitude relationship indicates that the local tip speed ratio is less than the preset tip speed ratio.

[0008] In an exemplary embodiment, determining the inflow angle of the blade element of the blade according to the local tip speed ratio includes: determining the inflow angle of the blade element of the blade based on the following formula: Including: φ = arctan (1 / λ r ), where λ r is the local tip speed ratio.

[0009] In an exemplary embodiment, determining the inflow angle of a blade element of the blade according to the lift line slope of the blade and the local tip speed ratio includes: acquiring the blade solidity, the angle of attack and the lift coefficient at zero angle of attack of the blade; and determining the inflow angle of the blade element of the blade according to the blade solidity, the angle of attack, the lift coefficient at zero angle of attack, the lift line slope and the local tip speed ratio.

[0010] In an exemplary embodiment, determining the inflow angle of the blade element of the blade according to the lift line slope of the blade and the local tip speed ratio includes: determining the inflow angle of the blade element according to the following formula: include:

[0011] Wherein, σ is the blade solidity, k l is the lift line slope, λ r is the local tip speed ratio, θ is the angle of attack, C l0 is the lift coefficient at zero angle of attack.

[0012] In an exemplary embodiment, determining the inflow angle of a blade element of the blade according to the lift line slope of the blade and the local tip speed ratio includes: acquiring the blade solidity, the angle of attack, the lift coefficient at zero angle of attack, and the tip loss of the blade; determining the inflow angle of the blade element of the blade according to the blade solidity, the angle of attack, the lift coefficient at zero angle of attack, the tip loss and the lift line slope and the local tip speed ratio.

[0013] In an exemplary embodiment, determining the inflow angle of the blade element of the blade according to the blade solidity of the blade, the angle of attack, the lift coefficient at zero angle of attack, the tip loss, the lift line slope and the local tip speed ratio comprises:

[0014] The inflow angle of the blade element is determined according to the following formula: include:

[0015] Among them, F tip is the tip loss, σ is the blade solidity, k l is the lift line slope, λ r is the local tip speed ratio, θ is the angle of attack, C l0 is the lift coefficient at zero angle of attack.

[0016] In an exemplary embodiment, obtaining the tip loss of the blade includes: obtaining the number of blades of a wind wheel, the radius of the wind wheel, the radial position of the blade and the sample inflow angle of the blade, wherein the wind wheel is the wind wheel corresponding to the blade; determining the tip loss of the blade according to the number of blades of the wind wheel, the radius of the wind wheel, the radial position of the blade and the sample inflow angle of the blade.

[0017] In an exemplary embodiment, before determining the inflow angle of the blade element of the blade according to the lift line slope of the blade and the local tip speed ratio, the method further includes: acquiring a sample angle of attack, a sample inflow angle, a sample lift coefficient, and a lift coefficient at zero angle of attack of the blade; and determining the lift line slope of the blade according to the sample angle of attack of the blade, the sample inflow angle, the sample lift coefficient, and the lift coefficient at zero angle of attack.

[0018] According to another aspect of an embodiment of the present application, a device for determining an inflow angle is also provided, including: a first determination module, used to determine the local tip speed ratio of the blade according to the incoming wind speed and the operating speed of the blade; a second determination module, used to determine the size relationship between the local tip speed ratio and a preset tip speed ratio; a third determination module, used to determine the inflow angle of the blade element of the blade according to the local tip speed ratio when the size relationship indicates that the local tip speed ratio is greater than or equal to the preset tip speed ratio; a fourth determination module, used to determine the inflow angle of the blade element of the blade according to the lift line slope of the blade and the local tip speed ratio when the size relationship indicates that the local tip speed ratio is less than the preset tip speed ratio.

[0019] According to another aspect of the embodiments of the present application, a computer-readable storage medium is provided, in which a computer program is stored, wherein the computer program is configured to execute the above-mentioned method for determining the inflow angle when running.

[0020] According to another aspect of an embodiment of the present application, an electronic device is provided, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the method for determining the inflow angle through the computer program.

[0021] According to another aspect of the embodiments of the present application, a computer program product is provided, including a computer program, wherein the computer program is executed by a processor to perform the above-mentioned method for determining the inflow angle.

[0022] Through the embodiment of the present application, the local tip speed ratio of the blade is determined according to the incoming wind speed and the operating speed of the blade; the magnitude relationship between the local tip speed ratio and the preset tip speed ratio is determined; when the magnitude relationship indicates that the local tip speed ratio is greater than or equal to the preset tip speed ratio, the inflow angle of the blade element of the blade is determined according to the local tip speed ratio; when the magnitude relationship indicates that the local tip speed ratio is less than the preset tip speed ratio, the inflow angle of the blade element of the blade is determined according to the lift line slope of the blade and the local tip speed ratio. That is, in the embodiment of the present application, the local tip speed ratio is calculated based on the incoming wind speed and the operating state of the blade, and then according to the magnitude relationship between the local tip speed ratio and the preset tip speed ratio, the blade element inflow angle is directly calculated according to the local tip speed ratio or "the lift line slope of the blade and the local tip speed ratio", the calculation process does not need iteration and the calculation speed is faster, which solves the problem of long calculation time or inaccurate calculation results for determining the inflow angle of the blade element in the related art. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The exemplary embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0024] Figure 1 is a hardware structure block diagram of a computer device for determining an inflow angle according to an embodiment of the present application;

[0025] Figure 2 is a flow chart of a method for determining an inflow angle according to an embodiment of the present application;

[0026] Figure 3 It is a structural block diagram of a device for determining an inflow angle according to an embodiment of the present application. DETAILED DESCRIPTION

[0027] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present application.

[0028] It should be noted that the terms and "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0029] The method embodiments provided in the embodiments of the present application can be executed in a computer device or a similar computing device. Taking running on a computer device as an example, Figure 1 is a hardware structure block diagram of a computer device for determining an inflow angle according to an embodiment of the present application. Figure 1 As shown, the computer device may include one or more ( Figure 1 Only one is shown in the figure) processor 102 (processor 102 may include but is not limited to a microprocessor (Microprocessor Unit, referred to as MPU) or a programmable logic device (Programmable logic device, referred to as PLD)) and a memory 104 for storing data. In an exemplary embodiment, the above-mentioned computer device may also include a transmission device 106 and an input and output device 108 for communication functions. It can be understood by those skilled in the art that Figure 1 The structure shown is only for illustration and does not limit the structure of the above-mentioned computer device. Figure 1 More or fewer components as shown, or with Figure 1 Equivalent functions or comparisons shown Figure 1 A different configuration with more features is shown.

[0030] The memory 104 can be used to store computer programs, for example, software programs and modules of application software, such as the computer program corresponding to the method for determining the inflow angle in the embodiment of the present application. The processor 102 executes various functional applications and data processing by running the computer program stored in the memory 104, which is equivalent to implementing the above method. The memory 104 may include a high-speed random access memory, and may also include a non-volatile memory, such as one or more magnetic storage devices, flash memory, or other non-volatile solid-state memory. In some examples, the memory 104 may further include a memory remotely arranged relative to the processor 102, and these remote memories may be connected to the computer device via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0031] The transmission device 106 is used to receive or send data via a network. The specific example of the above network may include a wireless network provided by a communication provider of the computer device. In one embodiment, the transmission device 106 includes a network adapter (Network Interface Controller, referred to as NIC), which can be connected to other network devices through a base station so as to communicate with the Internet. In one example, the transmission device 106 can be a radio frequency (RF) module, which is used to communicate with the Internet wirelessly.

[0032] In this embodiment, a method for determining an inflow angle is provided. Figure 2 is a flow chart of a method for determining an inflow angle according to an embodiment of the present application, which is executed in the above-mentioned computer device, and the flow chart includes the following steps:

[0033] Step S202, determining the local tip speed ratio of the blade according to the incoming wind speed and the running speed of the blade;

[0034] Step S204, determining the magnitude relationship between the local tip speed ratio and the preset tip speed ratio;

[0035] Step S206, when the magnitude relationship indicates that the local tip speed ratio is greater than or equal to the preset tip speed ratio, determining the inflow angle of the blade element of the blade according to the local tip speed ratio;

[0036] Step S208, when the magnitude relationship indicates that the local tip speed ratio is less than the preset tip speed ratio, determining the inflow angle of the blade element of the blade according to the lift line slope of the blade and the local tip speed ratio.

[0037] The blade elements of a large wind turbine blade refer to the many tiny ends that the wind turbine blade is divided into when it extends.

[0038] Through the above steps, the local tip speed ratio of the blade is determined according to the incoming wind speed and the operating speed of the blade; the magnitude relationship between the local tip speed ratio and the preset tip speed ratio is determined; when the magnitude relationship indicates that the local tip speed ratio is greater than or equal to the preset tip speed ratio, the inflow angle of the blade element of the blade is determined according to the local tip speed ratio; when the magnitude relationship indicates that the local tip speed ratio is less than the preset tip speed ratio, the inflow angle of the blade element of the blade is determined according to the lift line slope of the blade and the local tip speed ratio. That is, in the embodiment of the present application, the local tip speed ratio is calculated based on the incoming wind speed and the operating state of the blade, and then according to the magnitude relationship between the local tip speed ratio and the preset tip speed ratio, the blade element inflow angle is directly calculated according to the local tip speed ratio or "the lift line slope of the blade and the local tip speed ratio", the calculation process does not need iteration and the calculation speed is faster, which solves the problem of long calculation time or inaccurate calculation results for determining the inflow angle of the blade element in the related art.

[0039] Optionally, determining the inflow angle of the blade element of the blade according to the local tip speed ratio comprises: determining the inflow angle of the blade element of the blade based on the following formula: Including: φ = arctan (1 / λ r ), where λ r is the local tip speed ratio.

[0040] That is to say, when the above-mentioned local tip speed ratio is greater than or equal to the preset tip speed ratio, the inverse of the local tip speed ratio is calculated, and the arc tangent value of the inverse of the local tip speed ratio is solved, and the arc tangent value of the inverse is the inflow angle of the above-mentioned blade element.

[0041] Optionally, determining the inflow angle of the blade element of the blade according to the lift line slope of the blade and the local tip speed ratio includes: acquiring the blade solidity, angle of attack and lift coefficient of the blade at zero angle of attack; determining the inflow angle of the blade element of the blade according to the blade solidity, angle of attack, lift coefficient at zero angle of attack, lift line slope and the local tip speed ratio.

[0042] Optionally, determining the inflow angle of the blade element of the blade according to the lift line slope of the blade and the local tip speed ratio comprises: determining the inflow angle of the blade element according to the following formula: include:

[0043] Wherein, σ is the blade solidity, k l is the lift line slope, λ r is the local tip speed ratio, θ is the angle of attack, C l0 is the lift coefficient at zero angle of attack.

[0044] Without considering the loss, the inflow angle of the blade element of the blade may be determined based on the blade solidity of the blade, the angle of attack, the lift coefficient at zero angle of attack, the lift line slope and the local tip speed ratio.

[0045] Optionally, determining the inflow angle of the blade element of the blade according to the lift line slope of the blade and the local tip speed ratio includes: acquiring the blade solidity, angle of attack, lift coefficient and tip loss of the blade at a zero angle of attack; and determining the inflow angle of the blade element of the blade according to the blade solidity, angle of attack, lift coefficient at a zero angle of attack, tip loss and the lift line slope and the local tip speed ratio.

[0046] Optionally, determining the inflow angle of the blade element of the blade according to the blade solidity of the blade, the angle of attack, the lift coefficient at zero angle of attack, the tip loss, the lift line slope and the local tip speed ratio comprises:

[0047] The inflow angle of the blade element is determined according to the following formula: include:

[0048] Among them, F tip is the tip loss, σ is the blade solidity, k l is the lift line slope, λ r is the local tip speed ratio, θ is the angle of attack, C l0 is the lift coefficient at zero angle of attack.

[0049] For an actual wind turbine, the number of blades is always limited, so the influence of tip loss needs to be considered in the process of solving the inflow angle of the blade element. Therefore, considering the tip loss, the inflow angle of the blade element of the blade can be determined based on the blade solidity of the blade, the angle of attack, the lift coefficient at zero angle of attack, the tip loss, the lift line slope and the local tip speed ratio.

[0050] Among them, the tip loss can be obtained based on the following method: obtaining the number of blades of the wind wheel, the radius of the wind wheel, the radial position of the blade and the sample inflow angle of the blade, wherein the wind wheel is the wind wheel corresponding to the blade; determining the tip loss of the blade according to the number of blades of the wind wheel, the radius of the wind wheel, the radial position of the blade and the sample inflow angle of the blade.

[0051] Optionally, the tip loss is determined based on the following formula: in, B is the number of blades of the wind wheel, R is the radius of the wind wheel, r is the radial position of the blade, φ1 is the sample inflow angle of the blade, and φ1 is taken as the formula when the tip loss and hub loss are not considered. The result of the calculation.

[0052] Optionally, before determining the inflow angle of the blade element of the blade according to the lift line slope of the blade and the local tip speed ratio, the lift line slope also needs to be determined, and the implementation method is as follows: obtaining the sample angle of attack, sample inflow angle, sample lift coefficient and lift coefficient of the blade at zero angle of attack; determining the lift line slope of the blade according to the sample angle of attack of the blade, the sample inflow angle, the sample lift coefficient and the lift coefficient at zero angle of attack.

[0053] Optionally, the lift line slope k is determined based on the following formula: l , including: C l =k l (φ1-θ1)+C l0 , where φ1 is the sample inflow angle, θ1 is the sample attack angle, C l0 is the lift coefficient at zero angle of attack, C l is the sample lift coefficient.

[0054] In order to better understand the process of the method for determining the inflow angle, the process of the method for determining the inflow angle is described below in combination with an optional embodiment, but it is not used to limit the technical solution of the embodiment of the present application.

[0055] The embodiment of the present application provides a method for determining an inflow angle, and the specific steps are as follows:

[0056] Step 1: Build the model;

[0057] The incoming wind speed, operating speed and pitch angle of the blade will jointly determine the operating state of the blade. The incoming wind speed and operating speed can be expressed as the local tip speed ratio of the blade. This application will use the local tip speed ratio λ r The local tip speed ratio λ r The expression of is,

[0058] λ r =Ωr / V1 (Formula 1-1), where Ω is the operating speed, V1 is the incoming wind speed, and r is the radial position of the blade.

[0059] The local tip speed ratio λ r There are two cases to consider, one is λ r When it is greater than or equal to 4, one is λ r Less than 4.

[0060] (1) Analysis of inflow angles with high local tip speed ratios;

[0061] First, a parameter is introduced as the nominal inflow angle φ n , the nominal inflow angle refers to the inflow angle of the blade element when the induced velocity is not considered. Its expression is:

[0062] φ n =arctan(1 / λ r )(Formula 1-2);

[0063] The actual inflow angle φ of the blade can be converted into,

[0064] Among them, a is the axial induction factor, and b is the circumferential induction factor;

[0065] When the blade absorbs wind energy, its induction factor should meet the conditions: a>0, b>0 (Formula 1-4);

[0066] Then when λ r When ≥4, the actual inflow angle at this time satisfies: φ<arctan(1 / 4) (Formula 1-5);

[0067] Considering that the pitch angle and the twist angle are positive or close to zero, the angle of attack of the blade element satisfies the following inequality: α≤φ≤arctan(1 / 4) (Formula 1-6);

[0068] That is to say, the blade element is running in the range of attack angle below 15 degrees. Considering the actual situation, the blade element attack angle is running between -15 degrees and 15 degrees. For the airfoil in this range of attack angle, it has the following characteristics, compared with the lift coefficient C l , drag coefficient C d Very small, that is:

[0069] C d / C l →0(Formula 1-7);

[0070] On the other hand, the lift coefficient C of the airfoil l Basically, it shows a linear relationship with the angle of attack θ, which can be expressed as follows:

[0071] C l =k l (φ-θ)+C l0 (Formula 1-8);

[0072] In the above formula, k l is the slope of the lift line, C l0 is the lift coefficient corresponding to zero angle of attack.

[0073] At this time, the normal force coefficient and tangential force coefficient corresponding to the cross section are:

[0074]

[0075] According to the BEM theory, the tangential induction factor satisfies the following formula:

[0076] Among them, σ is the blade solidity, which can be understood as the ratio of the blade area to the rotor area;

[0077] According to the Taylor expansion of sine and cosine functions:

[0078]

[0079] Substitute (Formula 1-11) into (Formula 1-10). Since the inflow angle is small, φ is ignored. 3 And all of the above. Then there are:

[0080]

[0081] Because σC l / 4≈0, So the above formula can be transformed into:

[0082]

[0083] According to (Formula 1-13), (Formula 1-3) can be simplified to:

[0084]

[0085] And because:

[0086] Substituting (Formula 1-15) into (Formula 1-14) yields:

[0087]

[0088] (Formula 1-11) can be substituted into (Formula 1-16). Ignore φ 3 And the above items, and substitute (Formula 1-8) into it to get:

[0089]

[0090] because The above formula can be simplified to:

[0091]

[0092] According to the above formula and considering that it is an approximate expression, the inflow angle φ is taken as:

[0093]

[0094] because When λ rThe inflow angle is always close to zero, which is unreasonable. So the inflow angle φ is taken as:

[0095]

[0096] From the velocity triangle, the relative inflow velocity V0 is:

[0097]

[0098] In the same way, it can be simplified to

[0099]

[0100] Comparing (Formula 1-18) and (Formula 1-22), we can get:

[0101] V0=V1·λ r =Ωr(Formula 1-23);

[0102] So the thrust and tangential force of the blade element are,

[0103]

[0104] When considering the tip loss F tip When , the following method is used to calculate:

[0105]

[0106] in B is the number of blades of the wind rotor, R is the radius of the wind rotor, r is the radial position of the blade, and φ is taken as the result calculated by (Formula 1-20) without considering the tip loss and hub loss.

[0107] Considering that the tip loss factor is a correction to the infinite number of blades assumption, that is, a correction to the solidity, when considering the tip loss factor, (Formula 1-18) is expressed as the following formula for calculation:

[0108]

[0109] According to the above formula and the processing method from (Formula 1-19) to (Formula 1-20), the inflow angle φ when considering the blade tip loss can be obtained as:

[0110]

[0111] When considering the hub loss F hub A similar method can be used to calculate .

[0112] (2) Analysis of inflow angles at low local tip speed ratios;

[0113] When the local tip speed ratio of the blade element is less than 4, the blade element operates in the angle of attack range above the stall angle of attack. At this time, the drag coefficient cannot be ignored, and the lift curve and the angle of attack are not a simple linear relationship. The inflow velocity and inflow angle cannot be simplified into the above relationship. Only a rough estimate can be made.

[0114] 1) Analysis of inflow angle of cylindrical section:

[0115] Since the blade root section is often within a small local tip speed ratio range and the cross section is cylindrical, it has a characteristic that the lift coefficient is 0, so it can be directly deduced:

[0116] a=-b(Formula 1-28);

[0117] Then there is,

[0118] Therefore, for a cylindrical section, φ=φ n =arctan(1 / λ r )(Formula 1-30);

[0119] The inflow velocity V0 at this time is,

[0120] in, Since the Reynolds magnitude near the blade root is around 105 and the cross section here has little effect on the bending moment of the wind turbine, C d It is usually taken as 1.0, so a can be further simplified to a = σ / (4sinφ+σ).

[0121] 2) Analysis of inflow angle of non-circular cross section;

[0122] For other r The phylum, namely λ r When <4.0, the inflow velocity is approximately calculated using the following formula:

[0123]

[0124] Since when 1.5≤λ r When <4.0,φ 3 And the above items can still be ignored, so the inflow angle calculation at this time is still calculated using (Formula 1-27). r <1.5, use (Formula 1-30) to calculate the inflow angle.

[0125] It can be seen from (Formula 1-31) that when λ r When it increases, V0→Ωr. r The derivation is consistent when the larger value is taken. For the sake of consistency, the inflow velocity of all sections except the cylindrical section is expressed as,

[0126]

[0127] (3) Establishment of zero-iteration BEM method;

[0128] Combining the calculation formulas under the above conditions, it can be obtained that, except for the circular cross-section blade element at the blade root, the inflow velocity of all other blade elements is calculated using (Formula 1-33); for the inflow angle, when λ r ≥1.5, use (Formula 1-27) for calculation, and when λ r When <1.5, use (Formula 1-29) for calculation. The summary is as follows:

[0129]

[0130] φ=φ n =arctan(1 / λ r )(1.5>λ r >0);

[0131]

[0132] The embodiment of the present application proposes a simplified SBEM calculation method. The method directly calculates the blade element inflow angle based on the incoming wind conditions and the blade operating status. The calculation process does not require iteration and the calculation speed is faster, which is suitable for load calculation of large offshore wind turbines.

[0133] Through the description of the above implementation methods, those skilled in the art can clearly understand that the method according to the above embodiment can be implemented by means of software plus a necessary general hardware platform, and of course it can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art, can be embodied in the form of a software product, which is stored in a storage medium (such as ROX / RAX, a disk, or an optical disk), and includes a number of instructions for a terminal device (which can be a mobile phone, a computer, a server, or a network device, etc.) to execute the methods of each embodiment of the present application.

[0134] In this embodiment, a device for determining an inflow angle is also provided, which is used to implement the above-mentioned embodiments and preferred implementation modes, and will not be repeated hereafter. As used below, the term "module" may be a combination of software and / or hardware that implements a predetermined function. Although the devices described in the following embodiments are preferably implemented in software, the implementation of hardware, or a combination of software and hardware, is also possible and conceivable.

[0135] Figure 3 is a structural block diagram of a device for determining an inflow angle according to an embodiment of the present application, the device comprising:

[0136] A first determination module 32, configured to determine a local tip speed ratio of the blade according to an incoming wind speed and an operating speed of the blade;

[0137] A second determination module 34, used to determine the magnitude relationship between the local tip speed ratio and a preset tip speed ratio;

[0138] A third determination module 36, configured to determine an inflow angle of a blade element of the blade according to the local tip speed ratio when the magnitude relationship indicates that the local tip speed ratio is greater than or equal to the preset tip speed ratio;

[0139] The fourth determination module 38 is configured to determine the inflow angle of the blade element of the blade according to the lift line slope of the blade and the local tip speed ratio when the magnitude relationship indicates that the local tip speed ratio is less than the preset tip speed ratio.

[0140] Through the above device, the local tip speed ratio of the blade is determined according to the incoming wind speed and the operating speed of the blade; the magnitude relationship between the local tip speed ratio and the preset tip speed ratio is determined; when the magnitude relationship indicates that the local tip speed ratio is greater than or equal to the preset tip speed ratio, the inflow angle of the blade element of the blade is determined according to the local tip speed ratio; when the magnitude relationship indicates that the local tip speed ratio is less than the preset tip speed ratio, the inflow angle of the blade element of the blade is determined according to the lift line slope of the blade and the local tip speed ratio. That is, in the embodiment of the present application, the local tip speed ratio is calculated based on the incoming wind speed and the operating state of the blade, and then according to the magnitude relationship between the local tip speed ratio and the preset tip speed ratio, the blade element inflow angle is directly calculated according to the local tip speed ratio or "the lift line slope of the blade and the local tip speed ratio", the calculation process does not need iteration and the calculation speed is faster, which solves the problem of long calculation time or inaccurate calculation results for determining the inflow angle of the blade element in the related art.

[0141] In an exemplary embodiment, the third determination module 36 is used to determine the inflow angle of the blade element of the blade based on the following formula: Including: φ = arctan (1 / λ r ), where λ r is the local tip speed ratio.

[0142] In an exemplary embodiment, the fourth determination module 38 is used to obtain the blade solidity, angle of attack and lift coefficient of the blade at zero angle of attack; and determine the inflow angle of the blade element of the blade according to the blade solidity, angle of attack, lift coefficient at zero angle of attack, lift line slope and local tip speed ratio.

[0143] In an exemplary embodiment, the fourth determination module 38 is used to determine the inflow angle of the blade element according to the following formula: include:

[0144] Wherein, σ is the blade solidity, k l is the lift line slope, λ r is the local tip speed ratio, θ is the angle of attack, C l0 is the lift coefficient at zero angle of attack.

[0145] In an exemplary embodiment, the fourth determination module 38 is used to obtain the blade solidity, angle of attack, lift coefficient and tip loss of the blade at zero angle of attack; and determine the inflow angle of the blade element of the blade according to the blade solidity, angle of attack, lift coefficient at zero angle of attack, tip loss and lift line slope and the local tip speed ratio.

[0146] In an exemplary embodiment, the fourth determination module 38 is used to determine the inflow angle of the blade element according to the following formula: include:

[0147] Among them, F tip is the tip loss, σ is the blade solidity, k l is the lift line slope, λ r is the local tip speed ratio, θ is the angle of attack, C l0 is the lift coefficient at zero angle of attack.

[0148] In an exemplary embodiment, the fourth determination module 38 is used to obtain the number of blades of the wind wheel, the radius of the wind wheel, the radial position of the blade and the sample inflow angle of the blade, wherein the wind wheel is the wind wheel corresponding to the blade; and determine the tip loss of the blade according to the number of blades of the wind wheel, the radius of the wind wheel, the radial position of the blade and the sample inflow angle of the blade.

[0149] In an exemplary embodiment, the fourth determination module 38 is used to obtain the sample angle of attack, the sample inflow angle, the sample lift coefficient and the lift coefficient at zero angle of attack of the blade; and determine the lift line slope of the blade based on the sample angle of attack, the sample inflow angle, the sample lift coefficient and the lift coefficient at zero angle of attack of the blade.

[0150] Optionally, in this embodiment, the storage medium may be configured to store a computer program for performing the following steps:

[0151] S1, determining the local tip speed ratio of the blade according to the incoming wind speed and the running speed of the blade;

[0152] S2, determining the magnitude relationship between the local tip speed ratio and a preset tip speed ratio;

[0153] S3, when the magnitude relationship indicates that the local tip speed ratio is greater than or equal to the preset tip speed ratio, determining the inflow angle of the blade element of the blade according to the local tip speed ratio;

[0154] S4, when the magnitude relationship indicates that the local tip speed ratio is less than the preset tip speed ratio, determining the inflow angle of the blade element of the blade according to the lift line slope of the blade and the local tip speed ratio.

[0155] Optionally, the computer-readable storage medium may include, but is not limited to, various media that can store computer programs, such as a USB flash drive, a read-only memory (ROM), a random access memory (RAM), a mobile hard disk, a magnetic disk or an optical disk.

[0156] For specific examples in this embodiment, reference may be made to the examples described in the above embodiments and exemplary implementation modes, and this embodiment will not be described in detail herein.

[0157] An embodiment of the present application further provides an electronic device, including a memory and a processor, wherein a computer program is stored in the memory, and the processor is configured to run the computer program to execute the steps in any one of the above method embodiments.

[0158] Optionally, in this embodiment, the processor may be configured to perform the following steps through a computer program:

[0159] S1, determining the local tip speed ratio of the blade according to the incoming wind speed and the running speed of the blade;

[0160] S2, determining the magnitude relationship between the local tip speed ratio and a preset tip speed ratio;

[0161] S3, when the magnitude relationship indicates that the local tip speed ratio is greater than or equal to the preset tip speed ratio, determining the inflow angle of the blade element of the blade according to the local tip speed ratio;

[0162] S4, when the magnitude relationship indicates that the local tip speed ratio is less than the preset tip speed ratio, determining the inflow angle of the blade element of the blade according to the lift line slope of the blade and the local tip speed ratio.

[0163] Optionally, the electronic device may further include a transmission device and an input / output device, wherein the transmission device is connected to the processor, and the input / output device is connected to the processor.

[0164] An embodiment of the present application further provides a computer program product, which includes a computer program. When the computer program is executed by a processor, the steps in any one of the above method embodiments are implemented.

[0165] An embodiment of the present application further provides another computer program product, including a non-volatile computer-readable storage medium, wherein the non-volatile computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps in any of the above method embodiments are implemented.

[0166] An embodiment of the present application also provides a computer program, which includes computer instructions stored in a computer-readable storage medium; a processor of a computer device reads the computer instructions from the computer-readable storage medium, and the processor executes the computer instructions, so that the computer device performs the steps in any one of the above method embodiments.

[0167] For specific examples in this embodiment, reference may be made to the examples described in the above embodiments and exemplary implementation modes, and this embodiment will not be described in detail herein.

[0168] Obviously, those skilled in the art should understand that the above modules or steps of the present application can be implemented by a general computing device, they can be concentrated on a single computing device, or distributed on a network composed of multiple computing devices, they can be implemented by a program code executable by a computing device, so that they can be stored in a storage device and executed by the computing device, and in some cases, the steps shown or described can be executed in a different order from that herein, or they can be made into individual integrated circuit modules, or multiple modules or steps therein can be made into a single integrated circuit module for implementation. Thus, the present application is not limited to any specific combination of hardware and software.

[0169] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the principles of the present application shall be included in the protection scope of the present application.

Claims

1. A method for determining an inflow angle, characterized in that: include: Determining the local tip speed ratio of the blade according to the incoming wind speed and the operating speed of the blade; Determining a magnitude relationship between the local tip speed ratio and a preset tip speed ratio; In a case where the magnitude relationship indicates that the local tip speed ratio is greater than or equal to the preset tip speed ratio, determining an inflow angle of a blade element of the blade according to the local tip speed ratio; When the magnitude relationship indicates that the local tip speed ratio is less than the preset tip speed ratio, the inflow angle of the blade element of the blade is determined according to the lift line slope of the blade and the local tip speed ratio.

2. The method for determining the inflow angle according to claim 1, characterized in that: Determining the inflow angle of the blade element of the blade according to the local tip speed ratio comprises: The inflow angle of the blade element of the blade is determined based on the following formula: include: φ=arctan(1 / λ r ), where λ r is the local tip speed ratio.

3. The method for determining the inflow angle according to claim 1, characterized in that: Determining the inflow angle of the blade element of the blade according to the lift line slope of the blade and the local tip speed ratio comprises: Obtaining the blade solidity, angle of attack and lift coefficient of the blade at zero angle of attack; The inflow angle of a blade element of the blade is determined according to the blade solidity of the blade, the angle of attack, the lift coefficient at a zero angle of attack, the lift line slope and the local tip speed ratio.

4. The method for determining the inflow angle according to claim 3, characterized in that: Determining the inflow angle of the blade element of the blade according to the lift line slope of the blade and the local tip speed ratio comprises: The inflow angle of the blade element is determined according to the following formula: include: Wherein, σ is the blade solidity, k l is the lift line slope, λ r is the local tip speed ratio, θ is the angle of attack, C l0 is the lift coefficient at zero angle of attack.

5. The method for determining the inflow angle according to claim 1, characterized in that: Determining the inflow angle of the blade element of the blade according to the lift line slope of the blade and the local tip speed ratio comprises: Obtaining blade solidity, angle of attack, lift coefficient and tip loss of the blade at zero angle of attack; The inflow angle of a blade element of the blade is determined according to the blade solidity of the blade, the angle of attack, the lift coefficient at zero angle of attack, the tip loss, the lift line slope, and the local tip speed ratio.

6. The method for determining the inflow angle according to claim 5, characterized in that: Determining the inflow angle of the blade element of the blade according to the blade solidity of the blade, the angle of attack, the lift coefficient at zero angle of attack, the tip loss, the lift line slope and the local tip speed ratio comprises: The inflow angle of the blade element is determined according to the following formula: include: Among them, F tip is the tip loss, σ is the blade solidity, k l is the lift line slope, λ r is the local tip speed ratio, θ is the angle of attack, C l0 is the lift coefficient at zero angle of attack.

7. The method for determining the inflow angle according to claim 5, characterized in that: Obtaining the tip loss of the blade, comprising: Acquire the number of blades of a wind wheel, the radius of the wind wheel, the radial position of the blades, and the sample inflow angle of the blades, wherein the wind wheel is the wind wheel corresponding to the blades; The tip loss of the blade is determined according to the number of blades of the wind wheel, the radius of the wind wheel, the radial position of the blade and the sample inflow angle of the blade.

8. The method for determining the inflow angle according to claim 1, characterized in that: Before determining the inflow angle of the blade element of the blade according to the lift line slope of the blade and the local tip speed ratio, the method further comprises: Obtaining a sample angle of attack, a sample inflow angle, a sample lift coefficient, and a lift coefficient at zero angle of attack of the blade; A lift line slope of the blade is determined based on the sample angle of attack of the blade, the sample inflow angle, the sample lift coefficient, and the lift coefficient at zero angle of attack.

9. A device for determining an inflow angle, characterized in that: include: A first determination module is used to determine the local tip speed ratio of the blade according to the incoming wind speed and the running speed of the blade; A second determination module, used to determine the magnitude relationship between the local tip speed ratio and a preset tip speed ratio; A third determination module is configured to determine an inflow angle of a blade element of the blade according to the local tip speed ratio when the magnitude relationship indicates that the local tip speed ratio is greater than or equal to the preset tip speed ratio; A fourth determination module is used to determine the inflow angle of the blade element of the blade according to the lift line slope of the blade and the local tip speed ratio when the size relationship indicates that the local tip speed ratio is less than the preset tip speed ratio.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium includes a stored program, wherein the program executes the method described in any one of claims 1 to 8 when executed.

11. An electronic device comprising a memory and a processor, characterized in that: A computer program is stored in the memory, and the processor is configured to execute the method according to any one of claims 1 to 8 through the computer program.

12. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the method according to any one of claims 1 to 8 is implemented.

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