Wind turbine periodic independent pitch control method, device and electronic equipment

Abstract

The application discloses a wind turbine periodic independent variable pitch control method, device and electronic equipment. The control method comprises the following steps: obtaining a reference pitch angle; determining a first sub-additional pitch angle, a second sub-additional pitch angle and a third sub-additional pitch angle corresponding to three blades of an impeller respectively; superimposing the reference pitch angle with the first sub-additional pitch angle, the second sub-additional pitch angle and the third sub-additional pitch angle respectively to obtain a first pitch angle, a second pitch angle and a third pitch angle corresponding to the three blades respectively; and controlling the wind turbine to periodically and independently change the pitch according to the first pitch angle, the second pitch angle and the third pitch angle. The wind turbine periodic independent variable pitch control method can change the position of the blade with the change of the azimuth angle of the impeller, reduce the periodic alternating load of the blade root caused by the rotation of the impeller, and does not need to additionally install other sensors, thereby reducing the design cost of the unit.

Description

Technical Field

[0001] This application relates to the field of wind power technology, and in particular to a method, device and electronic equipment for periodic independent pitch control of wind turbine generators. Background Technology

[0002] During operation, the blade root load of a wind turbine will exhibit periodic alternating loads as the rotor rotates, such as... Figure 1 As shown, this will have a significant impact on the fatigue load of the blade root. Figure 1 The horizontal axis represents the impeller azimuth angle, the vertical axis represents the blade root load, and the three different curves represent different blades. The blue curve represents the blade root load of blade number one, the red curve represents the blade root load of blade number two, and the green curve represents the blade root load of blade number three. Summary of the Invention

[0003] The purpose of this application is to provide a method, device, and electronic device for periodic independent pitch control of wind turbine units.

[0004] In a first aspect, embodiments of this application provide a method for periodic independent pitch control of a wind turbine, including:

[0005] Obtain the reference pitch angle;

[0006] Determine the first sub-additional pitch angle, the second sub-additional pitch angle, and the third sub-additional pitch angle corresponding to the three blades of the impeller, respectively;

[0007] The reference pitch angle is superimposed with the first sub-addition pitch angle, the second sub-addition pitch angle and the third sub-addition pitch angle respectively to obtain the first pitch angle, the second pitch angle and the third pitch angle corresponding to the three blades respectively.

[0008] The wind turbine is controlled to periodically and independently pitch based on the first pitch angle, the second pitch angle, and the third pitch angle.

[0009] In some embodiments, determining the first sub-additional pitch angle, the second sub-additional pitch angle, and the third sub-additional pitch angle corresponding to the three blades of the impeller includes:

[0010] Using an aerodynamic model, the equivalent wind speed at the impeller surface is determined based on the collected rotor speed and output active power of the wind turbine.

[0011] Based on the equivalent wind speed on the impeller surface, determine the average wind speed and the corresponding turbulence within a preset time period;

[0012] Determine the additional pitch angle based on the average wind speed and turbulence;

[0013] Based on the additional pitch angle and the impeller azimuth angle, the first sub-additional pitch angle, the second sub-additional pitch angle, and the third sub-additional pitch angle corresponding to the three blades of the impeller are determined respectively.

[0014] In some embodiments, using an aerodynamic model, the equivalent wind speed at the rotor surface is determined based on the collected rotor speed and output active power of the wind turbine, including:

[0015] Using an aerodynamic model and based on environmental parameters, a table of wind energy utilization coefficients and a table of power losses for wind turbine units are generated.

[0016] Based on the collected rotor speed and active power output of the wind turbine, as well as the power loss table, the first ratio is determined; the first ratio is the ratio of the wind energy utilization coefficient of the wind turbine to the cube of the tip speed ratio.

[0017] The tip speed ratio is determined based on the first ratio, the collected blade pitch angle of the wind turbine, and the wind energy utilization coefficient table of the wind turbine.

[0018] The equivalent wind speed at the impeller surface is determined based on the tip speed ratio, the collected impeller speed and blade radius of the wind turbine.

[0019] In some embodiments, a first ratio is determined based on the collected rotor speed and output active power of the wind turbine, as well as a power loss table; the first ratio is the ratio of the wind energy utilization coefficient of the wind turbine to the cube of the tip speed ratio, including:

[0020] Collect the rotor speed and output active power of the wind turbine;

[0021] Based on the active power, find the corresponding power loss in the power loss table.

[0022] Based on the impeller speed, output power, and power loss, the first ratio is obtained according to the first formula;

[0023] The first formula includes:

[0024]

[0025] in, As the first ratio, C p P is the wind energy utilization coefficient of the wind turbine, λ is the tip speed ratio, and P is the tip speed ratio. out P represents the active power output of the wind turbine. loss Where ρ is the power loss, R is the air density, R is the blade radius, and ω is the impeller speed.

[0026] In some embodiments, determining the tip speed ratio based on the first ratio, the collected pitch angle of the wind turbine, and the wind energy utilization coefficient table of the wind turbine includes:

[0027] Based on the first ratio and the collected blade pitch angle of the wind turbine, find the blade tip speed ratio value corresponding to the first ratio in the wind energy utilization coefficient table of the wind turbine, and obtain the blade tip speed ratio.

[0028] In some embodiments, determining the average wind speed and corresponding turbulence over a preset time period based on the impeller surface equivalent wind speed includes:

[0029] The average wind speed within a preset time period is determined based on the equivalent wind speed of the impeller surface.

[0030] The turbulence corresponding to the average wind speed is determined based on the average wind speed and the equivalent wind speed on the impeller surface.

[0031] In some embodiments, determining the additional pitch angle based on average wind speed and turbulence includes:

[0032] The membership degree of the first fuzzy set is determined based on the average wind speed and the preset first fuzzy set; wherein, the first fuzzy set is the fuzzy set of the average wind speed.

[0033] Based on turbulence and a pre-defined second fuzzy set, determine the membership degree of the second fuzzy set; where the second fuzzy set is the fuzzy set of turbulence.

[0034] Based on the preset fuzzy control rules, the membership degree of the first fuzzy set, the membership degree of the second fuzzy set, and the preset third fuzzy set, the membership degree of the third fuzzy set is determined; wherein, the third fuzzy set is a fuzzy set with additional pitch angle.

[0035] The additional pitch angle is determined based on the membership degree of the third fuzzy set and the third fuzzy set.

[0036] In some embodiments, determining the additional pitch angle based on the membership degree of the third fuzzy set and the third fuzzy set includes:

[0037] Based on the membership degree of the third fuzzy set and the third fuzzy set, the additional propeller pitch angle is obtained according to the fifth formula;

[0038] The fifth formula includes;

[0039]

[0040] in, For the additional pitch angle, {PL out PM out PS out ,ZE out} is the third fuzzy set, {PL r PM r PS r ,ZE r} represents the membership degree of the third fuzzy set.

[0041] Secondly, embodiments of this application provide a periodic independent pitch control device for wind turbine generators, comprising:

[0042] The acquisition module is configured to acquire the reference pitch angle.

[0043] The determination module is configured to determine the first sub-additional pitch angle, the second sub-additional pitch angle, and the third sub-additional pitch angle corresponding to the three blades of the impeller, respectively.

[0044] The superposition module is configured to superimpose the reference pitch angle with the first sub-addition pitch angle, the second sub-addition pitch angle and the third sub-addition pitch angle respectively to obtain the first pitch angle, the second pitch angle and the third pitch angle corresponding to the three blades respectively.

[0045] The control module is configured to control the wind turbine to periodically and independently pitch according to the first pitch angle, the second pitch angle, and the third pitch angle.

[0046] Thirdly, embodiments of this application provide an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that the processor executes the computer program to implement the steps of the method provided in any of the above embodiments.

[0047] The wind turbine periodic independent pitch control method provided in this application embodiment involves superimposing the first, second, and third sub-additional pitch angles corresponding to the three blades of the rotor with a reference pitch angle to obtain the first, second, and third pitch angles corresponding to the three blades, respectively. Then, based on the first, second, and third pitch angles corresponding to the three blades, the wind turbine is controlled to periodically and independently pitch. This involves determining one blade position of each of the three rotor blades and then superimposing each blade position onto the unified blade position under normal control of the wind turbine to obtain the final blade position of each of the three rotor blades. Based on the final blade position of the three blades, the wind turbine is controlled to periodically and independently pitch, so that the blade position changes with the rotor azimuth angle. This reduces the periodic alternating load at the blade root caused by rotor rotation and eliminates the need for additional sensors, thus reducing the design cost of the turbine. Attached Figure Description

[0048] Figure 1 A schematic diagram of the blade root load under different impeller azimuth angles;

[0049] Figure 2 This is a flowchart illustrating a periodic independent pitch control method for a wind turbine according to an embodiment of this application.

[0050] Figure 3 This is a flowchart illustrating step S20 of an embodiment of this application;

[0051] Figure 4This is a flowchart illustrating step S21 of an embodiment of this application;

[0052] Figure 5 This is a flowchart illustrating step S22 in an embodiment of this application;

[0053] Figure 6 This is a flowchart illustrating step S23 in an embodiment of this application;

[0054] Figure 7 This is a schematic diagram of the structure of a wind turbine periodic independent pitch control device according to an embodiment of this application. Detailed Implementation

[0055] Various embodiments and features of this application are described herein with reference to the accompanying drawings.

[0056] It should be understood that various modifications can be made to the embodiments described herein. Therefore, the above description should not be considered as limiting, but merely as an example of embodiments. Other modifications within the scope and spirit of this application will be apparent to those skilled in the art.

[0057] The accompanying drawings, which are included in and form part of this specification, illustrate embodiments of the present application and, together with the general description of the present application given above and the detailed description of the embodiments given below, serve to explain the principles of the present application.

[0058] These and other features of this application will become apparent from the following description of preferred forms of embodiments given as non-limiting examples, with reference to the accompanying drawings.

[0059] It should also be understood that although this application has been described with reference to some specific examples, those skilled in the art can certainly implement many other equivalent forms of this application.

[0060] The above and other aspects, features and advantages of this application will become more apparent when taken in conjunction with the accompanying drawings and in view of the following detailed description.

[0061] Specific embodiments of this application are described thereafter with reference to the accompanying drawings; however, it should be understood that the claimed embodiments are merely examples of this application, which can be implemented in various ways. Well-known and / or repeated functions and structures are not described in detail to avoid unnecessary or redundant details that could obscure the application. Therefore, the specific structural and functional details claimed herein are not intended to be limiting, but merely serve as the basis and representative basis for the claims to teach those skilled in the art to use this application in a variety of substantially any suitable detailed structures.

[0062] This specification may use the phrases “in one embodiment,” “in another embodiment,” “in yet another embodiment,” or “in other embodiments,” all of which may refer to one or more of the same or different embodiments according to this application.

[0063] This application provides a method for periodic independent pitch control of wind turbine generators, such as... Figure 2 As shown, the periodic independent pitch control method for this wind turbine includes:

[0064] S10, obtain the reference pitch angle;

[0065] S20, determine the first sub-additional pitch angle, the second sub-additional pitch angle, and the third sub-additional pitch angle corresponding to the three blades of the impeller respectively;

[0066] S30, superimpose the reference pitch angle with the first sub-addition pitch angle, the second sub-addition pitch angle and the third sub-addition pitch angle respectively to obtain the first pitch angle, the second pitch angle and the third pitch angle corresponding to the three blades respectively.

[0067] S40 controls the wind turbine to periodically and independently pitch according to the first pitch angle, the second pitch angle, and the third pitch angle.

[0068] The pitch angle, or blade position, refers to the first, second, and third sub-additional pitch angles corresponding to the three blades of the impeller, which are also the blade positions corresponding to the three blades of the impeller. The reference pitch angle is the uniform pitch angle used for normal control of the wind turbine, which is also the uniform blade position used for normal control of the wind turbine.

[0069] The wind turbine periodic independent pitch control method provided in this application embodiment involves superimposing the first, second, and third sub-additional pitch angles corresponding to the three blades of the rotor with a reference pitch angle to obtain the first, second, and third pitch angles corresponding to the three blades, respectively. Then, based on the first, second, and third pitch angles corresponding to the three blades, the wind turbine is controlled to periodically and independently pitch. This involves determining one blade position of each of the three rotor blades and then superimposing each blade position onto the unified blade position under normal control of the wind turbine to obtain the final blade position of each of the three rotor blades. Based on the final blade position of the three blades, the wind turbine is controlled to periodically and independently pitch, so that the blade position changes with the rotor azimuth angle. This reduces the periodic alternating load at the blade root caused by rotor rotation and eliminates the need for additional sensors, thus reducing the design cost of the turbine.

[0070] In some embodiments, such as Figure 3As shown, the first sub-additional pitch angle, the second sub-additional pitch angle, and the third sub-additional pitch angle corresponding to the three blades of the impeller are determined, including:

[0071] S21. Using an aerodynamic model, the equivalent wind speed on the impeller surface is determined based on the collected impeller speed and output active power of the wind turbine.

[0072] S22, determine the average wind speed and corresponding turbulence within a preset time period based on the equivalent wind speed of the impeller surface;

[0073] S23, determine the additional pitch angle based on the average wind speed and turbulence;

[0074] S24. Based on the additional pitch angle and the impeller azimuth angle, determine the first sub-additional pitch angle, the second sub-additional pitch angle, and the third sub-additional pitch angle corresponding to the three blades of the impeller.

[0075] Because the wind speed measured by the nacelle anemometer is affected by the rotor rotation and cannot represent the true wind speed in front of the rotor, this application uses the operating state of the wind turbine to estimate the equivalent wind speed on the rotor surface in front of the rotor, and further calculates the average wind speed and the corresponding turbulence. The detailed process is as follows:

[0076] In some embodiments, such as Figure 4 As shown, using an aerodynamic model, the equivalent wind speed at the rotor surface is determined based on the collected rotor speed and output active power of the wind turbine, including:

[0077] S211 uses an aerodynamic model to generate a table of wind energy utilization coefficients and a table of power loss for wind turbine units based on environmental parameters.

[0078] An aerodynamic model is established using wind turbine simulation software. Based on environmental parameters (such as wind speed, wind direction, and air density), the corresponding wind energy utilization coefficient table and power loss table for the wind turbine are generated. The wind energy utilization coefficient table is Cp(λ). 3 The power loss table (also known as the loss power table or input power table) is where Cp is the wind energy utilization coefficient of the wind turbine, λ is the tip speed ratio, β is the pitch angle, and Cp(λ) is the blade angle. 3 The table (β) is shown in Table 1. The first row of Table 1 contains the blade pitch angle β (e.g., -1, -0.4, 0.2, 0.8…), and the first column on the left contains the tip speed ratio λ (e.g., 1, 1.3, 1.6, 1.9…). The values ​​in Table 1 (e.g., 0.004426, 0.004624, 0.002446063…) represent Cp / λ. 3 The power loss table is shown in Table 2. LOSS Power is the power loss, and INPUT Power is the active power output by the wind turbine. The active power output by the wind turbine corresponds to the power loss.

[0079] Table 1: Cp(λ) 3 ,β) table

[0080]

[0081] Table 2: Power Loss Table

[0082]

[0083] S212. Based on the collected rotor speed and output active power of the wind turbine, as well as the power loss table, determine the first ratio; the first ratio is the ratio of the wind energy utilization coefficient of the wind turbine to the cube of the tip speed ratio.

[0084] Optionally, a first ratio is determined based on the collected rotor speed and output active power of the wind turbine, as well as a power loss table; the first ratio is the ratio of the wind energy utilization coefficient of the wind turbine to the cube of the tip speed ratio, specifically including:

[0085] Collect the rotor speed and output active power of the wind turbine;

[0086] Based on the active power, find the corresponding power loss in the power loss table.

[0087] Based on the impeller speed, output power, and power loss, the first ratio is obtained according to the first formula;

[0088] The first formula includes:

[0089]

[0090] in, As the first ratio, C p P is the wind energy utilization coefficient of the wind turbine, λ is the tip speed ratio, and P is the tip speed ratio. out The active power output of the wind turbine generator, i.e., INPUT Power in Table 2, P loss The value is the power loss, which is the LOSS Power in Table 2. ρ is the air density, R is the blade radius, and ω is the impeller speed.

[0091] For example, collecting the active power P of a wind turbine. out Given a power loss of 3077 kW, find the power loss P corresponding to 3077 kW in the power loss table. loss The active power P is 216.8kW. out and power loss P loss Substituting into the first formula above, we obtain the first ratio.

[0092] S213. Determine the tip speed ratio based on the first ratio, the collected pitch angle of the wind turbine, and the wind energy utilization coefficient table of the wind turbine.

[0093] Optionally, the tip speed ratio is determined based on the first ratio, the collected pitch angle of the wind turbine, and the wind energy utilization coefficient table of the wind turbine, including:

[0094] Based on the first ratio and the collected blade pitch angle of the wind turbine, find the blade tip speed ratio value corresponding to the first ratio in the wind energy utilization coefficient table of the wind turbine, and obtain the blade tip speed ratio.

[0095] For example, if the pitch angle β of the wind turbine is 0.2, the first ratio is calculated. If the value is 0.0021, then look up the wind energy utilization coefficient table for wind turbine units, Cp(λ). 3 ,β) table, lookup and calculation of values The closest tip velocity ratio λ is 1.6.

[0096] S214. Based on the tip speed ratio, the collected impeller speed and blade radius of the wind turbine, the equivalent wind speed on the impeller surface is determined.

[0097] Optionally, based on the tip speed ratio, the collected impeller speed and blade radius of the wind turbine, the equivalent wind speed V at the impeller surface is obtained according to the second formula. e ;

[0098] The second formula includes:

[0099]

[0100] Among them, V e ω is the equivalent wind speed on the impeller surface, R is the blade radius, and λ is the tip speed ratio.

[0101] In some embodiments, such as Figure 5 As shown, based on the equivalent wind speed on the impeller surface, the average wind speed and corresponding turbulence over a preset time period are determined, including:

[0102] S221, determine the average wind speed within a preset time period based on the equivalent wind speed of the impeller surface;

[0103] The preset time can be 3 minutes, 5 minutes, or 10 minutes, etc.

[0104] For example, if 300 parameters (such as the rotor speed and output active power of a wind turbine) are collected within a preset time, then 300 equivalent wind speeds V on the rotor surface will be obtained. e V ei , i = 1, 2, ..., n, where n = 300.

[0105] Optionally, based on the equivalent wind speed of the impeller surface, the average wind speed V over a preset time period can be obtained according to the third formula. avg ;

[0106] The third formula includes:

[0107]

[0108] Among them, V avg Let n be the average wind speed, and n be the equivalent wind speed V on the impeller surface calculated within a preset time. e The number of parameters, that is, the number of parameters collected, V ei The equivalent wind speed for one impeller surface.

[0109] S222, determine the turbulence corresponding to the average wind speed based on the average wind speed and the equivalent wind speed on the impeller surface.

[0110] Optionally, based on the average wind speed and the equivalent wind speed on the impeller surface, the turbulence I corresponding to the average wind speed can be obtained according to the fourth formula;

[0111] The fourth formula includes:

[0112]

[0113] Where I represents turbulence, V ei For the equivalent wind speed of a single impeller surface, V avg This represents the average wind speed.

[0114] In some embodiments, such as Figure 6 As shown, the additional pitch angle is determined based on the average wind speed and turbulence, including:

[0115] S231, Determine the membership degree of the first fuzzy set based on the average wind speed and the preset first fuzzy set; wherein, the first fuzzy set is the fuzzy set of the average wind speed;

[0116] S232, Determine the membership degree of the second fuzzy set based on the turbulence and the preset second fuzzy set; wherein, the second fuzzy set is the fuzzy set of the turbulence;

[0117] For example, the first fuzzy set of preset average wind speed is {PL} v PM v PS v ,ZE v}; The second fuzzy set of the preset turbulence is {PL} i PM i PS i ,ZE i The membership function of each fuzzy set is in normal form, i.e.

[0118]

[0119] Where x represents the average wind speed or turbulence, a and b are vectors corresponding to the fuzzy sets, and μ A This represents the membership degree of the average wind speed or turbulence in the fuzzy set.

[0120] The specific explanation is as follows: For the first fuzzy set of average wind speed, for example, a = [20, 10, 5, 0], b = [5, 8, 8, 10]. Assuming the current average wind speed x is 5 m / s, then according to the following formula, this value belongs to PL. v The membership degree is

[0121]

[0122] calculate The result was 0.0001234. Belonging to PL v The membership degree. Similarly, the membership degree of PM can be calculated using the formula above. v PS v ZE v The degree of membership.

[0123] Similarly, for the second fuzzy set of turbulence, for example, a = [30, 15, 5, 0] and b = [5, 5, 5, 10], according to the formula above and the same calculation method, the membership degree of each element in the second fuzzy set of the current turbulence can be calculated.

[0124] S233, based on the preset fuzzy control rules, the membership degree of the first fuzzy set, the membership degree of the second fuzzy set, and the preset third fuzzy set, determine the membership degree of the third fuzzy set; wherein, the third fuzzy set is a fuzzy set with additional pitch angle.

[0125] Specifically, fuzzy control rules can be defined based on the wind turbine characteristic curve, as follows:

[0126] a) When the average wind speed is high and the turbulence is high, the additional pitch angle is large;

[0127] b) When the average wind speed is high and the turbulence is moderate, the additional pitch angle is large;

[0128] c) When the average wind speed is high and the turbulence is low, the additional pitch angle is moderate;

[0129] d) When the average wind speed is relatively high and the turbulence is close to 0, the additional pitch angle is moderate;

[0130] e) When the average wind speed is moderate and the turbulence is high, the additional pitch angle is moderate;

[0131] f) When the average wind speed and turbulence are moderate, the additional pitch angle is moderate;

[0132] g) When the average wind speed is moderate and the turbulence is low, the additional pitch angle is small;

[0133] h) When the average wind speed is moderate and the turbulence is close to 0, the additional pitch angle is small;

[0134] i) When the average wind speed is low and the turbulence is high, the additional pitch angle is small;

[0135] j) When the average wind speed is low and the turbulence is moderate, the additional pitch angle is small;

[0136] k) When the average wind speed is low and the turbulence is low, the additional pitch angle is close to 0;

[0137] l) When the average wind speed is low and the turbulence is close to 0, the additional pitch angle is close to 0;

[0138] When the average wind speed is close to 0 and the turbulence is large, the additional pitch angle is close to 0.

[0139] n) When the average wind speed is close to 0 and the turbulence is moderate, the additional pitch angle is close to 0.

[0140] o) When the average wind speed is close to 0 and the turbulence is relatively small, the additional pitch angle is close to 0;

[0141] p) When the average wind speed is close to 0 and the turbulence is close to 0, the additional pitch angle is close to 0.

[0142] Among them, the additional pitch angles of large, medium, small, and close to zero are defined as {PL}. out PM out PS out ,ZE out}, that is, the third fuzzy set with additional pitch angle is {PL} out PM out PS out ,ZE out}

[0143] S234. Determine the additional pitch angle based on the membership degree of the third fuzzy set and the third fuzzy set.

[0144] Continuing with the previous example, the third fuzzy set {PL out PM out PS out ,ZE out For example, the specific numerical values ​​are [2.5, 0.75, 0.15, 0]. Based on the above 16 fuzzy control rules (a~p), the membership degree of the third fuzzy set is obtained according to the following formula: {PL} r PM rPS r ,ZE r}. Using PL r For example:

[0145]

[0146] in, The average wind speed in fuzzy control rule a is relatively high. The turbulence is relatively large in fuzzy control rule a. The average wind speed is relatively high in fuzzy control rule b. For fuzzy control rule b, the turbulence level is considered moderate. The above formula can be understood as first minimizing the values ​​of "significant average wind speed" and "significant turbulence" in fuzzy control rule a, then minimizing the values ​​of "significant average wind speed" and "moderate turbulence" in fuzzy control rule b, and finally taking the maximum value between the two minimum values ​​to obtain the membership degree PL of the third fuzzy set. r Similarly, following the method described above, the membership degree PM of the third fuzzy set can be obtained. r PS r ,ZE r .

[0147] In some embodiments, determining the additional pitch angle based on the membership degree of the third fuzzy set and the third fuzzy set includes:

[0148] Based on the membership degree of the third fuzzy set and the third fuzzy set, the additional propeller pitch angle is obtained according to the fifth formula;

[0149] The fifth formula includes;

[0150]

[0151] in, For the additional pitch angle, {PL out PM out PS out ,ZE out} is the third fuzzy set, {PL r PM r PS r ,ZE r} represents the membership degree of the third fuzzy set.

[0152] In some embodiments, determining the first sub-additional pitch angle, the second sub-additional pitch angle, and the third sub-additional pitch angle corresponding to the three blades of the impeller based on the additional pitch angle and the impeller azimuth angle includes:

[0153] According to the additional pitch angle and impeller azimuth angle According to the sixth formula, the first sub-additional pitch angles corresponding to the three blades of the impeller are obtained respectively. Second sub-addition propeller pitch angle and the third additional propeller pitch angle

[0154] The sixth formula includes:

[0155]

[0156] in, To add pitch angle, This is the impeller azimuth angle.

[0157] This application employs a fuzzy control method to obtain additional pitch requirements, namely a first sub-additional pitch angle, a second sub-additional pitch angle, and a third sub-additional pitch angle, based on wind speed and turbulence. These three sub-additional pitch angles are then superimposed on the reference pitch angle obtained from the normal control of the wind turbine to obtain the first, second, and third pitch angles corresponding to the three blades, respectively. Based on these pitch angles, the wind turbine is controlled to periodically and independently pitch, causing the blade position to change with the rotor azimuth angle. This reduces the periodic alternating load at the blade root caused by rotor rotation and eliminates the need for additional sensors, thus lowering the turbine design cost.

[0158] Since the alternating load on the blade root is less affected when the wind speed is relatively low, and thus has less impact on the stability of the wind turbine, the conditions for operation can be increased.

[0159] Optionally, the wind turbine is controlled to periodically and independently pitch according to the first pitch angle, the second pitch angle, and the third pitch angle, including:

[0160] When the average wind speed is greater than the preset value, the wind turbine is controlled to periodically and independently pitch according to the first pitch angle, the second pitch angle and the third pitch angle.

[0161] The preset value can be 5m / s, 5.5m / s, etc.

[0162] For example, when the average wind speed is greater than 5 m / s, the method of this application is used to control the wind turbine to periodically and independently pitch according to the first pitch angle, the second pitch angle and the third pitch angle.

[0163] Based on the same inventive concept, embodiments of this application provide a periodic independent pitch control device for wind turbine generators, such as... Figure 7 As shown, the wind turbine's periodic independent pitch control device includes:

[0164] The acquisition module is configured to acquire the reference pitch angle.

[0165] The determination module is configured to determine the first sub-additional pitch angle, the second sub-additional pitch angle, and the third sub-additional pitch angle corresponding to the three blades of the impeller, respectively.

[0166] The superposition module is configured to superimpose the reference pitch angle with the first sub-addition pitch angle, the second sub-addition pitch angle and the third sub-addition pitch angle respectively to obtain the first pitch angle, the second pitch angle and the third pitch angle corresponding to the three blades respectively.

[0167] The control module is configured to control the wind turbine to periodically and independently pitch according to the first pitch angle, the second pitch angle, and the third pitch angle.

[0168] The wind turbine periodic independent pitch control method provided in this application includes an acquisition module, a determination module, a superposition module, and a control module. It obtains the first, second, and third pitch angles corresponding to the three blades of the rotor by superimposing the determined first, second, and third sub-additional pitch angles to a reference pitch angle. Then, based on these angles, the wind turbine is controlled to periodically and independently pitch. This involves determining one blade position for each of the three rotor blades and superimposing these positions onto a unified blade position for normal turbine control, resulting in the final blade positions for each blade. Finally, based on these final blade positions, the wind turbine is controlled to periodically and independently pitch, causing the blade positions to change with the rotor azimuth angle. This reduces the periodic alternating load at the blade root caused by rotor rotation and eliminates the need for additional sensors, thus lowering turbine design costs.

[0169] Based on the same inventive concept, this application provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. The device is characterized in that the processor executes the computer program to implement the steps of the wind turbine periodic independent pitch control method provided in any of the above embodiments.

[0170] The implementation methods and effects of the electronic devices provided in this application can be referred to the foregoing embodiments, and will not be repeated here.

[0171] The above embodiments are merely exemplary embodiments of this application and are not intended to limit this application. The scope of protection of this application is defined by the claims. Those skilled in the art can make various modifications or equivalent substitutions to this application within its substance and scope of protection, and such modifications or equivalent substitutions should also be considered to fall within the scope of protection of this application.

Claims

1. A method of periodic independent pitch control of a wind turbine, characterized in that, The method comprises: acquiring a reference pitch angle; determining a first sub-additional pitch angle, a second sub-additional pitch angle and a third sub-additional pitch angle corresponding to three blades of an impeller respectively; superimposing the reference pitch angle with the first sub-additional pitch angle, the second sub-additional pitch angle and the third sub-additional pitch angle respectively to obtain a first pitch angle, a second pitch angle and a third pitch angle corresponding to the three blades respectively; controlling periodic independent pitching of a wind turbine according to the first pitch angle, the second pitch angle and the third pitch angle; wherein the determining of the first sub-additional pitch angle, the second sub-additional pitch angle and the third sub-additional pitch angle corresponding to the three blades of the impeller comprises: determining an equivalent wind speed on an impeller surface according to the collected impeller rotating speed and output active power of the wind turbine by using an aerodynamic model; determining an average wind speed and corresponding turbulence within a preset time according to the equivalent wind speed on the impeller surface; determining an additional pitch angle according to the average wind speed and the turbulence; determining the first sub-additional pitch angle, the second sub-additional pitch angle and the third sub-additional pitch angle corresponding to the three blades of the impeller according to the additional pitch angle and an impeller azimuth angle; wherein the determining of the additional pitch angle according to the average wind speed and the turbulence comprises: determining a membership degree of a first fuzzy set according to the average wind speed and the first fuzzy set; wherein the first fuzzy set is a fuzzy set of the average wind speed; determining a membership degree of a second fuzzy set according to the turbulence and the second fuzzy set; wherein the second fuzzy set is a fuzzy set of the turbulence; determining a membership degree of a third fuzzy set according to a preset fuzzy control rule, the membership degree of the first fuzzy set, the membership degree of the second fuzzy set and the third fuzzy set; wherein the third fuzzy set is a fuzzy set of the additional pitch angle; determining the additional pitch angle according to the membership degree of the third fuzzy set and the third fuzzy set.

2. The method of claim 1, wherein, The determining of the equivalent wind speed on the impeller surface according to the collected impeller rotating speed and output active power of the wind turbine by using the aerodynamic model comprises: generating a wind energy utilization coefficient table and a power loss table of the wind turbine based on environmental parameters by using the aerodynamic model; determining a first ratio according to the collected impeller rotating speed and output active power of the wind turbine and the power loss table; the first ratio is a ratio of the wind energy utilization coefficient of the wind turbine to the cube of the tip speed ratio; determining the tip speed ratio according to the first ratio and the collected pitch angle of the wind turbine and the wind energy utilization coefficient table of the wind turbine; determining the equivalent wind speed on the impeller surface according to the tip speed ratio, the collected impeller rotating speed and the radius of the blade.

3. The method of claim 2, wherein, The determining of the first ratio according to the collected impeller rotating speed and output active power of the wind turbine and the power loss table comprises: collecting the impeller rotating speed and the output active power of the wind turbine; looking up a loss power corresponding to the active power in the power loss table according to the active power. ​ According to the impeller rotating speed, the active power and the loss power, a first ratio is obtained according to a first formula; The first formula comprises: wherein, is a first ratio, is a wind turbine wind energy utilization coefficient, is a tip speed ratio, is an active power output by the wind turbine, is a loss power, is an air density, R is a blade radius, and ω is a rotor speed.

4. The method of claim 2, wherein, According to the first ratio and the collected pitch angle of the wind turbine, and a wind energy utilization coefficient table of the wind turbine, a tip speed ratio is determined, comprising: According to the first ratio and the collected pitch angle of the wind turbine, a tip speed ratio value corresponding to the first ratio in the wind energy utilization coefficient table of the wind turbine is searched, to obtain the tip speed ratio.

5. The method of claim 1, wherein, According to the impeller face equivalent wind speed, an average wind speed in a preset time and a corresponding turbulence are determined, comprising: According to the impeller face equivalent wind speed, an average wind speed in a preset time is determined; According to the average wind speed and the impeller face equivalent wind speed, a turbulence corresponding to the average wind speed is determined.

6. The method of claim 1, wherein, According to the membership degree of the third fuzzy set and the third fuzzy set, an additional pitch angle is determined, comprising: According to the membership degree of the third fuzzy set and the third fuzzy set, an additional pitch angle is obtained according to a fifth formula; The fifth formula comprises: wherein, is an additional pitch angle, , , , is a third fuzzy set, , , , is a membership of the third fuzzy set.

7. A wind turbine generator periodic independent pitch control device, characterized by, Comprising: An acquisition module is configured to acquire a reference pitch angle; A determination module is configured to determine a first sub-additional pitch angle, a second sub-additional pitch angle and a third sub-additional pitch angle corresponding to three blades of an impeller respectively; wherein the determination of the first sub-additional pitch angle, the second sub-additional pitch angle and the third sub-additional pitch angle corresponding to the three blades of the impeller respectively comprises: determining an impeller face equivalent wind speed according to the collected impeller rotating speed and the output active power of the wind turbine by using an aerodynamic model; determining an average wind speed in a preset time and a corresponding turbulence according to the impeller face equivalent wind speed; determining an additional pitch angle according to the average wind speed and the turbulence; determining the first sub-additional pitch angle, the second sub-additional pitch angle and the third sub-additional pitch angle corresponding to the three blades of the impeller respectively according to the additional pitch angle and an impeller azimuth angle; wherein the determination of the additional pitch angle according to the average wind speed and the turbulence comprises: determining a membership degree of a first fuzzy set according to the average wind speed and the first fuzzy set; wherein the first fuzzy set is a fuzzy set of the average wind speed; determining a membership degree of a second fuzzy set according to the turbulence and the second fuzzy set; wherein the second fuzzy set is a fuzzy set of the turbulence; determining a membership degree of a third fuzzy set according to a preset fuzzy control rule, the membership degree of the first fuzzy set, the membership degree of the second fuzzy set and a third fuzzy set; wherein the third fuzzy set is a fuzzy set of the additional pitch angle; determining the additional pitch angle according to the membership degree of the third fuzzy set and the third fuzzy set; A superposition module is configured to superimpose the reference pitch angle respectively with the first sub-additional pitch angle, the second sub-additional pitch angle and the third sub-additional pitch angle, to obtain a first pitch angle, a second pitch angle and a third pitch angle corresponding to the three blades respectively; A control module is configured to control the wind turbine to periodically and independently pitch according to the first pitch angle, the second pitch angle and the third pitch angle.

8. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, The processor, when executing the computer program, implements the steps of the method according to any one of claims 1 to 6.

Images