Variable pitch control method of wind generating set under wind shear wind condition and generating set

Abstract

The invention provides a variable pitch control method of a wind generating set under a wind shear wind condition and the wind generating set, and the variable pitch control method comprises the following steps: based on wind speed data, determining a first characteristic quantity of the wind speed of first incoming wind of an impeller of the wind generating set and a second characteristic quantity of the wind speed of second incoming wind of the impeller; respectively determining a first trend quantity of the first characteristic quantity and a second trend quantity of the second characteristic quantity; determining a wind shear condition between the first incoming wind and the second incoming wind based on the first trend quantity and the second trend quantity; and on the basis of the wind shear wind condition, variable pitch control is conducted on the wind generating set. According to the variable pitch control method of the wind generating set and the wind generating set, the problem of lack of identification and set control under the wind shear wind condition is solved, variable pitch control can be performed on the wind generating set based on the wind shear wind condition, the limit load problem and the clearance problem can be solved in time, and the safety of the set is ensured.

Description

Technical Field

[0001] The present disclosure relates to the field of wind power generation, and more specifically, to a pitch control method of a wind turbine generator set under wind shear conditions and a wind turbine generator set. Background Art

[0002] As the impeller diameter and overall capacity of wind turbines increase, the overall cost constraints also increase. The clearance or extreme load issues of wind turbines become important influencing factors in the development process of the unit, especially under extreme wind shear conditions.

[0003] However, in the relevant technology, there is a lack of identification methods related to wind shear conditions and corresponding unit control strategies, which means that when facing wind shear conditions, the clearance problem or extreme load problem of the wind turbine generator set cannot be effectively solved, thereby affecting the safety and reliability of the unit. Summary of the invention

[0004] In view of the lack of identification and unit control under wind shear conditions in the related art, the present disclosure provides a pitch control method of a wind turbine generator set under wind shear conditions and a generator set.

[0005] A first aspect of the present disclosure provides a pitch control method for a wind turbine under a wind shear condition, the pitch control method comprising: determining a first characteristic quantity of a wind speed of a first incoming wind at an impeller of the wind turbine and a second characteristic quantity of a wind speed of a second incoming wind at the impeller based on wind speed data; determining a first trend quantity of the first characteristic quantity and a second trend quantity of the second characteristic quantity respectively, wherein the first trend quantity represents a cumulative amount of changes in the first characteristic quantity within a preset time period before the first incoming wind reaches the impeller, and the second trend quantity represents a cumulative amount of changes in the second characteristic quantity within the preset time period; determining a wind shear condition between the first incoming wind and the second incoming wind based on the first trend quantity and the second trend quantity; and performing pitch control on the wind turbine based on the wind shear condition.

[0006] Optionally, the first trend quantity and the second trend quantity are determined in the following manner: the first trend quantity is determined based on the cumulative amount of the first characteristic quantity within the preset time period and the cumulative amount of the first initial value of the first characteristic quantity within the preset time period; the second trend quantity is determined based on the cumulative amount of the second characteristic quantity within the preset time period and the cumulative amount of the second initial value of the second characteristic quantity within the preset time period, wherein the first initial value is the first characteristic quantity at a specific moment within the preset time period, and the second initial value is the second characteristic quantity at a specific moment within the preset time period.

[0007] Optionally, determining the wind shear condition between the first wind and the second wind based on the first trend quantity and the second trend quantity includes: determining a first difference between the first characteristic quantity and the second characteristic quantity based on the cumulative amount of the first characteristic quantity within the preset time period and the cumulative amount of the second characteristic quantity within the preset time period; determining the wind shear condition based on the first trend quantity, the second trend quantity and the first difference.

[0008] Optionally, determining the wind shear condition based on the first trend quantity, the second trend quantity and the first difference quantity includes: determining the second difference quantity between the first trend quantity and the second trend quantity; determining a wind shear parameter based on the first difference quantity and the second difference quantity, wherein the wind shear parameter characterizes the degree of wind shear between the first incoming wind and the second incoming wind; and determining the wind shear condition based on the wind shear parameter.

[0009] Optionally, the first difference amount and the second difference amount are both positive numbers, or the first difference amount and the second difference amount are both negative numbers.

[0010] Optionally, determining the wind shear condition between the first incoming wind and the second incoming wind based on the first trend quantity and the second trend quantity includes: determining the existence of wind shear conditions in response to the first trend quantity satisfying a first preset condition, the first trend quantity satisfying a second preset condition and the first difference quantity satisfying a third preset condition, or in response to the first difference quantity satisfying the third preset condition within a preset time length after the first trend quantity satisfies the first preset condition and the first trend quantity satisfies the second preset condition, wherein the first preset condition indicates that the cumulative amount of changes in the first characteristic quantity within the preset time period exceeds the design trend boundary of the wind turbine generator set; the second preset condition indicates that the cumulative amount of changes in the second characteristic quantity within the preset time period exceeds the design trend boundary of the wind turbine generator set; the third preset condition indicates that the difference between the first characteristic quantity and the second characteristic quantity exceeds the design difference boundary of the wind turbine generator set, wherein the numerical value of the design trend boundary of the first preset condition and the numerical value of the design trend boundary of the second preset condition are reciprocal numbers of each other.

[0011] Optionally, the wind turbine generator set is pitch controlled in the following manner: based on the wind shear conditions and wind speed-related quantities, an additional pitch angle is determined, wherein the wind speed-related quantity is a parameter related to the wind speed currently experienced by the wind turbine generator set; based on the additional pitch angle, the wind turbine generator set is pitch controlled.

[0012] Optionally, the first characteristic quantity and the second characteristic quantity are determined in the following manner: based on a wind measuring device, wind speed data at multiple points on multiple paths pointing from the incoming wind side to the impeller are obtained; based on the wind speed data, the direction of each path, the distance of each of the multiple points from the impeller, and the wind speed processing parameters on the impeller at the current moment, the composite wind speed on each path at the current moment is determined, wherein the wind speed processing parameters are determined based on the first characteristic quantity and the second characteristic quantity at the previous moment; based on the composite wind speed on each path at the current moment, the first characteristic quantity and the second characteristic quantity at the current moment are determined.

[0013] Optionally, pitch control is performed on the wind turbine generator set in the following manner: based on the first characteristic quantity and the second characteristic quantity, a wind speed characteristic quantity of the wind coming in front of the impeller is determined; according to the degree to which the wind speed characteristic quantity deviates from the rated wind speed of the wind turbine generator set, an additional pitch angle is determined; based on the additional pitch angle, pitch control is performed on the wind turbine generator set, wherein the degree to which the wind speed characteristic quantity deviates from the rated wind speed is negatively correlated with the additional pitch angle.

[0014] Optionally, determining the additional pitch angle according to the degree to which the wind speed characteristic quantity deviates from the rated wind speed of the wind turbine generator set includes: determining a plurality of wind speed intervals and candidate additional pitch angles corresponding to each wind speed interval based on the rated wind speed, cut-in wind speed, cut-out wind speed and a preset correction value of the wind turbine generator set; and determining the candidate additional pitch angle corresponding to the wind speed interval satisfied by the wind speed characteristic quantity as the additional pitch angle.

[0015] Optionally, the multiple wind speed intervals include a first wind speed interval, a second wind speed interval and a third wind speed interval, the first wind speed interval is determined based on a preset correction value and the rated wind speed, and includes the rated wind speed; the second wind speed interval is determined based on the cut-in wind speed of the wind turbine and the first wind speed interval, and is less than the first wind speed interval; the third wind speed interval is determined based on the cut-out wind speed of the wind turbine and the first wind speed interval, and is greater than the first wind speed interval, wherein the candidate additional pitch angle corresponding to the first wind speed interval is greater than the candidate additional pitch angle corresponding to the third wind speed interval and the candidate additional pitch angle corresponding to the first wind speed interval.

[0016] A second aspect of the present disclosure provides a computer device, comprising: at least one processor; and at least one memory storing computer executable instructions, wherein the computer executable instructions, when executed by the at least one processor, prompt the at least one processor to execute the pitch control method of a wind turbine generator set under wind shear conditions according to an embodiment of the present disclosure.

[0017] A third aspect of the present disclosure provides a wind turbine generator set, wherein the wind turbine generator set comprises the computer device according to the embodiment of the present disclosure.

[0018] A fourth aspect of the present disclosure provides a computer-readable storage medium, which, when instructions in the computer-readable storage medium are executed by at least one processor, prompts the at least one processor to execute the pitch control method of a wind turbine generator set under wind shear conditions according to an embodiment of the present disclosure.

[0019] According to the pitch control method and generator set of the wind turbine generator set under wind shear conditions disclosed in the present invention, the characteristic quantities of different wind speeds of the impeller can be determined based on wind speed data, and their respective trend quantities can be determined according to the characteristic quantities of different wind speeds. The trend quantity can characterize the cumulative amount of changes in the characteristic quantity of wind speed over a period of time. Based on such trend quantities, the wind shear conditions can be judged more accurately, so that the pitch control of the wind turbine generator set can be performed based on the wind shear conditions, so as to deal with extreme load problems and clearance problems in a timely manner and ensure the safety of the unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 is a schematic flow chart showing a pitch control method of a wind turbine generator system under wind shear conditions according to an exemplary embodiment of the present disclosure.

[0021] Figure 2 It is a schematic flow chart showing the steps of determining a first characteristic quantity and a second characteristic quantity in a pitch control method of a wind turbine generator set under a wind shear condition according to an exemplary embodiment of the present disclosure.

[0022] Figure 3 is a schematic diagram showing how wind speed data is acquired in a pitch control method of a wind turbine generator set under wind shear conditions according to an exemplary embodiment of the present disclosure.

[0023] Figure 4 is a schematic flow chart showing steps of determining a synthetic wind speed in a pitch control method of a wind turbine generator system under a wind shear condition according to an exemplary embodiment of the present disclosure.

[0024] Figure 5 is a schematic diagram showing a change trend of a positive shear wind condition in a pitch control method of a wind turbine generator set under a wind shear wind condition according to an exemplary embodiment of the present disclosure.

[0025] Figure 6 is a schematic diagram showing a change trend of a negative shear wind condition in a pitch control method of a wind turbine generator set under a wind shear wind condition according to an exemplary embodiment of the present disclosure.

[0026] Figure 7is a schematic flow chart showing an example of steps of determining wind shear conditions in a pitch control method of a wind turbine generator system under wind shear conditions according to an exemplary embodiment of the present disclosure.

[0027] Figure 8 is a schematic flow chart showing another example of the step of determining the wind shear condition in the pitch control method of a wind turbine generator system under the wind shear condition according to an exemplary embodiment of the present disclosure.

[0028] Fig. 9 is a schematic flow chart showing an example of pitch control steps in a pitch control method of a wind turbine generator system under wind shear conditions according to an exemplary embodiment of the present disclosure.

[0029] Fig.10 is a schematic diagram showing fuzzy control based on average wind speed and trend quantity in a pitch control method of a wind turbine generator set under wind shear conditions according to an exemplary embodiment of the present disclosure.

[0030] Fig.11 is a schematic diagram showing fuzzy control based on a pitch angle and a trend value in a pitch control method of a wind turbine generator set under a wind shear condition according to an exemplary embodiment of the present disclosure.

[0031] Fig.12 1 is a schematic architecture diagram showing another example of pitch control steps in a pitch control method of a wind turbine generator system under wind shear conditions according to an exemplary embodiment of the present disclosure.

[0032] Fig.13 is a schematic flow chart showing steps of determining an additional pitch angle in a pitch control method of a wind turbine under wind shear conditions according to an exemplary embodiment of the present disclosure.

[0033] Fig.14 1 is a schematic diagram showing a nonlinear relationship change curve between wind speed and additional pitch angle in a pitch control method of a wind turbine generator set under wind shear conditions according to an exemplary embodiment of the present disclosure.

[0034] Fig.15 It is a schematic diagram showing a comparison of blade root loads of a wind turbine generator set under wind shear conditions using a pitch control method according to an exemplary embodiment of the present disclosure and a wind turbine generator set not using a pitch control method.

[0035] Fig.16 1 is a schematic diagram showing a comparison of the clearances of a wind turbine generator set under wind shear conditions using a pitch control method according to an exemplary embodiment of the present disclosure and a wind turbine generator set not using a pitch control method.

[0036] Fig.17It is a schematic diagram showing a comparison of nacelle acceleration of a wind turbine generator set under wind shear conditions using a pitch control method according to an exemplary embodiment of the present disclosure and a wind turbine generator set not using a pitch control method. DETAILED DESCRIPTION

[0037] The following specific embodiments are provided to help the reader obtain a comprehensive understanding of the methods, devices and / or systems described herein. However, after understanding the disclosure of the present application, various changes, modifications and equivalents of the methods, devices and / or systems described herein will be clear. For example, the order of operations described herein is only an example and is not limited to those orders set forth herein, but can be changed as will be clear after understanding the disclosure of the present application, except for operations that must occur in a specific order. In addition, for greater clarity and simplicity, the description of features known in the art may be omitted.

[0038] The features described herein can be implemented in different forms and should not be construed as being limited to the examples described herein. Rather, the examples described herein have been provided to illustrate only some of the many possible ways to implement the methods, devices, and / or systems described herein, which will be clear after understanding the disclosure of the present application.

[0039] As used herein, the term "and / or" includes any one of the associated listed items and any combination of any two or more.

[0040] Although terms such as "first", "second", and "third" may be used herein to describe various members, components, regions, layers, or portions, these members, components, regions, layers, or portions should not be limited by these terms. Instead, these terms are only used to distinguish one member, component, region, layer, or portion from another member, component, region, layer, or portion. Therefore, without departing from the teachings of the examples described herein, the first member, first component, first region, first layer, or first portion referred to in the examples may also be referred to as the second member, second component, second region, second layer, or second portion.

[0041] In the specification, when an element (such as a layer, a region, or a substrate) is described as being “on”, “connected to”, or “coupled to” another element, the element may be directly “on”, “connected to”, or “coupled to” another element, or one or more other elements may be present therebetween. Conversely, when an element is described as being “directly on”, “directly connected to”, or “directly coupled to” another element, there may be no other elements present therebetween.

[0042] The terms used herein are only used to describe various examples and are not intended to limit the disclosure. Unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. The terms "comprise", "include" and "have" indicate the presence of the described features, quantities, operations, components, elements and / or combinations thereof, but do not exclude the presence or addition of one or more other features, quantities, operations, components, elements and / or combinations thereof.

[0043] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as those generally understood by a person of ordinary skill in the art to which the present disclosure belongs after understanding the present disclosure. Unless explicitly defined as such herein, terms (such as those defined in a general dictionary) should be interpreted as having a meaning consistent with their meaning in the context of the relevant art and the present disclosure, and should not be interpreted in an idealized or overly formal manner.

[0044] Furthermore, in the description of examples, when it is considered that a detailed description of a well-known related structure or function would cause vague interpretation of the present disclosure, such a detailed description will be omitted.

[0045] As mentioned above, in the relevant technology, there is a lack of identification methods related to wind shear conditions and corresponding unit control strategies, which results in the inability to effectively solve the clearance problem or extreme load problem of wind turbines under wind shear conditions, affecting the safety and reliability of the unit.

[0046] In view of the above problems, the present disclosure provides a pitch control method of a wind turbine generator set under wind shear conditions, a computer device, a wind turbine generator set and a computer-readable storage medium to solve or at least alleviate the above problems.

[0047] According to a first aspect of an exemplary embodiment of the present disclosure, a pitch control method of a wind turbine generator set under wind shear conditions is provided. The pitch control method of the wind turbine generator set can be performed by an electronic device with a computing and analysis function, the electronic device can be a terminal device or a server, wherein the terminal device can be a tablet computer, a laptop computer, a digital assistant, etc.; the server can be an independent server, a server cluster, a cloud computing platform or a virtualization center.

[0048] In an example application scenario, an electronic device that executes a pitch control method for a wind turbine generator set under wind shear conditions according to an embodiment of the present disclosure can determine a first characteristic quantity of the wind speed of a first incoming wind at an impeller of the wind turbine generator set and a second characteristic quantity of the wind speed of a second incoming wind at an impeller based on wind speed data, and can determine a first trend quantity of the first characteristic quantity and a second trend quantity of the second characteristic quantity, respectively. Here, the first trend quantity represents the cumulative amount of changes in the first characteristic quantity within a preset time period before the first incoming wind reaches the impeller, and the second trend quantity refers to the cumulative amount of changes in the second characteristic quantity within a preset time period before the second incoming wind reaches the impeller.

[0049] The electronic device can also determine the wind shear condition between the first wind and the second wind based on the first trend quantity and the second trend quantity, and can perform pitch control on the wind turbine generator set based on the wind shear condition.

[0050] Here, the electronic device may be communicatively connected to a database or a data management system, for example, and the database or the data management system may store measured wind speed data or estimated wind speed data, so that the electronic device may execute the above method based on the wind speed data.

[0051] According to the pitch control scheme of the wind turbine generator set disclosed in the present invention, the wind shear condition can be judged more accurately, and the pitch control of the wind turbine generator set can be performed based on the wind shear condition to promptly deal with extreme load problems and clearance problems to ensure the safety of the unit.

[0052] According to an exemplary embodiment of the present disclosure, a pitch control method of a wind turbine generator set under wind shear conditions may include the following steps:

[0053] like Figure 1 As shown, in step S110, a first characteristic value of a wind speed of a first incoming wind at an impeller of the wind turbine generator system and a second characteristic value of a wind speed of a second incoming wind at the impeller may be determined based on the wind speed data.

[0054] In this step, the wind speed data may be measured by wind measuring equipment such as laser radar, millimeter wave ranging radar, microwave radar, sodar, etc. However, the embodiments of the present disclosure are not limited thereto, and may also be obtained by other devices or methods, for example, may also be estimated by a machine learning model or an empirical model.

[0055] The first wind and the second wind may be winds from different positions on the impeller. As an example, the first wind may be wind from the upper side of the impeller, and the second wind may be wind from the lower side of the impeller; or, the first wind may be wind from the right side of the impeller, and the second wind may be wind from the left side of the impeller, but it is not limited thereto, for example, the first wind may be wind from the upper right side of the impeller, and the second wind may be wind from the lower left side of the impeller.

[0056] The characteristic quantity of wind speed can characterize the characteristics of wind speed, which can be obtained by reconstructing the wind speed of corresponding incoming wind based on wind speed data, for example, it can be an equivalent wind speed.

[0057] As an example, the first feature quantity and the second feature quantity may be determined in the following manner:

[0058] like Figure 2 As shown, in step S210, wind speed data at multiple points on multiple paths from the incoming wind side to the impeller may be acquired based on a wind measuring device.

[0059] In the process of wind blowing from the windward side to the impeller, the wind speed may change. Here, the wind speed at multiple points on multiple paths pointing to the impeller can be obtained, so that the change trend of the wind speed can be analyzed more three-dimensionally and accurately. The multiple paths can have different directions.

[0060] For example, Figure 3 As shown, taking the wind measuring device as a four-beam pulse laser radar as an example, the wind speed data of multiple range gates can be measured simultaneously, and the wind speed of each beam at multiple range gates can be obtained. For example, four paths S1, S2, S3 and S4 formed by four beams can be selected to measure the wind speed at two range gates on each path, such as point P11 and point P12 on path S1, point P21 and point P22 on path S2, point P31 and point P32 on path S3, and point P41 and point P42 on path S4. In this way, point P11, point P21, point P31 and point P41 can be in the same plane, and point P12, point P22, point P32 and point P42 can be in the same plane.

[0061] It should be noted that, although the above example uses four paths and two points on each path to obtain wind speed data, the embodiments of the present disclosure are not limited to this, and more or fewer paths may be selected, and / or more or fewer points may be selected on each path.

[0062] In step S220, the synthetic wind speed on each path at the current moment may be determined based on the wind speed data, the direction of each path, the distance of each of the multiple points from the impeller, and the wind speed processing parameters on the impeller at the current moment.

[0063] In this step, in one example, the wind speed processing parameter on the impeller at the current moment can be determined based on the first characteristic quantity and the second characteristic quantity at the previous moment, for example, it can be the average value of the first characteristic quantity at the previous moment and the second characteristic quantity at the previous moment. In the example of determining the wind speed processing parameter based on the first characteristic quantity and the second characteristic quantity, the correlation of the wind speed in time series can be established, so that the obtained wind speed processing parameter is more in line with the change trend of the actual wind speed and can better reflect the wind speed characteristics on the impeller.

[0064] Here, the wind speed processing parameters at the initial moment may be estimated or measured using other methods, for example, by measuring with an anemometer installed at or near the impeller.

[0065] In another example, the wind speed processing parameter on the impeller at any current moment can be measured by an anemometer installed at or near the impeller.

[0066] The wind speed processing parameter may be, for example, an average wind speed, but is not limited thereto, and may also be other wind speed parameters that can characterize the wind speed conditions at the impeller, such as the equivalent wind speed of the entire impeller.

[0067] As an example, the direction of each path can be represented by the angle between the path and the horizontal line, but it is not limited thereto and can also be represented by other means, such as the angle between the path and the vertical line, the angle between the path and another path, vector coordinates, etc. Specifically, the extension direction of the path can be arbitrary. For example, the direction of the light beam emitted by the laser radar can be divergent. In the case of calculating the synthetic wind speed, the extension direction of the path can be converted to a direction perpendicular to the impeller surface. Therefore, the direction of the path can be represented by the angle between the path and the horizontal line perpendicular to the impeller surface.

[0068] The distance of each point from the impeller may be, for example, the distance from a range gate where the point is located to the impeller, and the distance may be read, for example, from a wind measuring device.

[0069] In step S220, based on the wind speed data, the direction of each path, the distance of each point in the multiple points from the impeller, and the wind speed processing parameters on the impeller at the current moment, the wind speed of each point on each path can be synthesized to obtain a synthesized wind speed on the path. The synthesized wind speed can, for example, represent the average wind speed at each point on the path when the wind moves to the impeller.

[0070] As an example, for each path, the resultant wind speed can be determined as follows:

[0071] like Figure 4 As shown, in step S410, the target time corresponding to each point can be determined based on the wind speed processing parameters on the impeller at the current moment and the distance of each point from the impeller in the plurality of points.

[0072] In this step, the target time corresponding to each point indicates the time when the wind moving to the nearest measurement point at the current time is at the point, where the nearest measurement point is the point closest to the impeller among the multiple points on each path. Specifically, the wind is always moving, and the wind blowing to the nearest measurement point at the current time will pass through the point on the above path at the previous target time. The target time is related to the distance from the point to the nearest measurement point and the wind speed. As an example, the nearest measurement point can be on the distance gate closest to the impeller, and the distance between each point and the nearest measurement point can be the distance between the distance gate where the point is located and the distance gate closest to the impeller.

[0073] Taking the wind speed processing parameter as the average wind speed on the impeller at the current moment as an example, the distance of each point from the nearest measuring point can be divided by the average wind speed to obtain the movement time of the wind from the point to the nearest measuring point, so that the target time can be calculated based on the current moment and the movement time.

[0074] For example, Figure 3 For example, based on the distance x between point P12 and the impeller j , the distance x1 to the nearest measuring point and the average wind speed of the impeller The time Δt required for the wind to move from point P12 to the impeller can be determined 12 ,Right now Based on the current time t, the target time can be determined as (t-Δt 12 ). By analogy, the target time corresponding to each point on each path can be determined.

[0075] In step S420, the measurement data of the wind speed at each point at the corresponding target time may be determined according to the wind speed data.

[0076] When the target time corresponding to each point is determined, the wind speed of the point at the corresponding target time can be extracted from the wind speed data, for example, RAWS ij (t-Δt ij ).

[0077] In step S430, the composite wind speed may be determined based on the measured data of the wind speed at each point at the corresponding target time and the direction of each path.

[0078] As an example, when the wind speeds of all points on the path at the corresponding target time are obtained, the average wind speed of these points in a specific direction may be calculated.

[0079] For example, the composite wind speed of the ith path at the current moment can be expressed by the following formula (1):

[0080]

[0081] Wherein, i represents the number of the path, for example, for a four-beam radar, the value of i can be 1, 2, 3, 4; j represents the number of the point on the path, for example, it can be the number of the range gate; θ i represents the direction of the i-th path, such as the angle between the path and the horizontal line; t represents the current time; x j represents the measured distance of the jth point, such as the measured distance of the jth range gate; x1 represents the measured distance of the first point; u represents the wind speed processing parameter at the current moment, such as the average wind speed at the current moment; RAWS ij (x) represents the measured value of the wind speed along the path direction at the jth point of the i-th path at time x, and n represents the number of points on the path, such as the number of range gates.

[0082] Here, since a wind measuring device is used to measure the wind speed in front of the impeller in real time and the wind speed can be converted to the measurement distance of the first point, risky wind conditions can be identified in advance, so that the pitch can be changed in advance, making the pitch protection control more effective.

[0083] By determining the composite wind speed in the above manner, the wind speeds of multiple points on each path can be comprehensively considered to determine the total composite wind speed of the path, thereby reflecting the wind speed status on the entire path, making subsequent wind speed calculations more accurate.

[0084] In step S230, the first characteristic quantity and the second characteristic quantity at the current moment may be determined based on the composite wind speed on each path at the current moment.

[0085] In this step, the first characteristic quantity and the second characteristic quantity can be determined using the composite wind speed of each path. Specifically, as described above, each composite wind speed can reflect the wind speed state on the corresponding path. When the composite wind speeds of multiple paths are obtained, the first characteristic quantity of the first wind and the second characteristic quantity of the second wind can be obtained by further fusing these composite wind speeds.

[0086] In the example where the first wind is the wind from the upper side of the impeller and the second wind is the wind from the lower side of the impeller, Figure 3 For example, according to the measurement directions corresponding to the numbers of each path, assuming that path S1 and path S2 represent two paths on the upper side of the impeller, and path S3 and path S4 represent two paths on the lower side of the impeller, a first characteristic quantity such as the equivalent wind speed on the upper side of the impeller and a second characteristic quantity such as the equivalent wind speed on the lower side of the impeller can be obtained.

[0087] Specifically, the first feature quantity U can be expressed by the following equations (2) and (3): high and the second characteristic quantity U low :

[0088]

[0089]

[0090] In the example where the first wind is the wind from the left side of the impeller and the second wind is the wind from the right side of the impeller, Figure 3 For example, according to the measurement direction corresponding to the number of each path, assuming that path S1 and path S4 represent two paths on the left side of the impeller, and path S2 and path S3 represent two paths on the right side of the impeller, then a first characteristic quantity such as the equivalent wind speed on the left side of the impeller and a second characteristic quantity such as the equivalent wind speed on the right side of the impeller can be obtained.

[0091] Specifically, the first feature quantity U can be expressed by the following equations (4) and (5): left and the second characteristic quantity U right :

[0092]

[0093]

[0094] As described above, the first characteristic quantity and the second characteristic quantity of the expected position can be reconstructed based on the wind speed data. The first characteristic quantity and the second characteristic quantity obtained by the above wind speed reconstruction method can better reflect the wind speed state of the corresponding position, making the prediction of the wind speed more accurate, thereby improving the control effect of the unit.

[0095] Although an example of wind speed reconstruction is given above, it is not limited thereto, and other wind speed reconstruction methods may be used according to different measurement locations and measurement methods of wind speed data.

[0096] In addition, although the above describes that the first characteristic quantity and the second characteristic quantity are obtained by wind speed reconstruction, the method of determining the first characteristic quantity and the second characteristic quantity is not limited to this. For example, the first characteristic quantity and the second characteristic quantity can be obtained by using the wind speed data of the first wind and the second wind through difference, fitting, etc.

[0097] In step S120 , a first trend amount of the first feature amount and a second trend amount of the second feature amount may be determined respectively.

[0098] Here, the first trend quantity may represent the cumulative amount of changes in the first characteristic quantity within a preset time period before the first wind reaches the impeller, and the second trend quantity may represent the cumulative amount of changes in the second characteristic quantity within the preset time period.

[0099] Wind shear (also known as wind shear) is an atmospheric phenomenon that can represent the change of wind vector with wind direction and wind speed in the horizontal and / or vertical distances in the air. Wind shear can include positive shear and negative shear. Wind shear conditions include positive shear wind conditions and negative shear wind conditions in the horizontal direction, and positive shear wind conditions and negative shear wind conditions in the vertical direction.

[0100] For example, vertical wind shear may refer to the change of the wind vector over the vertical distance in the air, wherein the vertical negative shear wind condition may be manifested as the wind speed value at a low distance being greater than the wind speed value at a high distance, and the vertical positive shear wind condition may be manifested as the wind speed value at a high distance being greater than the wind speed value at a low distance; horizontal wind shear may refer to the change of the wind vector over the horizontal distance in the air, wherein the horizontal negative shear wind condition may be manifested as the wind speed value on one horizontal side (e.g. the left side or the right side) being greater than the wind speed value on the other horizontal side (e.g. the right side or the left side), and the horizontal positive shear wind condition may be manifested as the wind speed value on one horizontal side being less than the wind speed value on the other horizontal side.

[0101] Since the local wind speed may increase or decrease rapidly in a short period of time under wind shear conditions, the extreme wind shear conditions can be identified more accurately and timely by calculating the cumulative amount of changes in the first characteristic quantity and the second characteristic quantity over a period of time, so that the unit control strategy can be adopted in a timely manner.

[0102] As an example, the first trend quantity and the second trend quantity can be determined in the following manner: the first trend quantity can be determined based on the cumulative amount of the first characteristic quantity within the preset time period and the cumulative amount of the first initial value of the first characteristic quantity within the preset time period; the second trend quantity can be determined based on the cumulative amount of the second characteristic quantity within the preset time period and the cumulative amount of the second initial value of the second characteristic quantity within the preset time period.

[0103] Here, the first initial value may be a first characteristic value at a specific moment in a preset time period, and the second initial value may be a second characteristic value at a specific moment in a preset time period. The length of the preset time period may be determined according to actual needs, and the specific moment may be, for example, the initial moment of the preset time period.

[0104] Specifically, the change in the cumulative amount of a characteristic quantity (such as a first characteristic quantity or a second characteristic quantity) within a preset time period can be determined based on the difference between the cumulative amount of the characteristic quantity within the preset time period and the cumulative amount of the characteristic quantity within the preset time period at the initial moment of the preset time period.

[0105] For example, Figure 5 An example curve of wind speed versus time under positive shear wind conditions is shown, as Figure 5 As shown, if the current time is t0, the initial time of the preset time period is (t0-Δt), and the length of the preset time period is Δt.

[0106] In this case, taking the first wind as the upper wind of the impeller and the second wind as the lower wind of the impeller as an example, the first trend quantity S high It can be expressed by the following formula (6):

[0107]

[0108] Among them, U high (t) represents the first feature quantity, represents the cumulative amount of the first feature value within a preset time period, U high (t0-Δt)×Δt represents the first initial value U of the first feature quantity. high0 The cumulative amount over a preset time period.

[0109] Reference Figure 5 The curve shown can be considered as the difference between the area under the curve of the first characteristic quantity within the preset time period (i.e., the area formed by the curve and the horizontal axis within the preset time period) and the accumulated area of ​​the first characteristic quantity at the initial moment after the preset time period (i.e., the area of ​​the rectangle formed by the size of the first characteristic quantity at the initial moment and the length of the preset time period).

[0110] Similarly, the second trend quantity S low It can be expressed by the following formula (7):

[0111]

[0112] Among them, U low (t) represents the second feature quantity, represents the accumulation of the second feature value within a preset time period, U low (t0-Δt)-Δt represents the second initial value U of the second feature quantity. low0 The cumulative amount over a preset time period.

[0113] Reference Figure 5 The curve shown can be considered as the area of ​​the second characteristic quantity at the initial moment accumulated over the preset time period (i.e., the area of ​​the rectangle formed by the second characteristic quantity at the initial moment and the length of the preset time period) and the area on the curve of the second characteristic quantity within the preset time period (i.e., the area of ​​the curve within the preset time period and the second initial value U low0 The difference in area formed).

[0114] Figure 6 An example curve of wind speed and time under negative shear wind conditions is shown. Although the area representation of the first trend quantity and the second trend quantity is not shown, it can be understood that it is similar to the above Figure 5 The representation and calculation method of are similar, so I will not go into details here.

[0115] In addition, in the example where the first wind is the wind from the left side of the impeller and the second wind is the wind from the right side of the impeller, the first trend quantity and the second trend quantity may have expressions similar to those of the above-mentioned equations (6) and (7), for example, as shown in the following equations (8) and (9):

[0116]

[0117]

[0118] Among them, U left (t) represents the first feature quantity, represents the cumulative amount of the first feature value within a preset time period, U left (t0-Δt)×Δt represents the accumulation of the first initial value of the first characteristic quantity within the preset time period; U right (t) represents the second feature quantity, represents the accumulation of the second feature value within a preset time period, U right (t0-Δt)×Δt represents the accumulation amount of the second initial value of the second feature amount within the preset time period.

[0119] In the above manner, the trend quantity is determined by utilizing the difference between the two cumulative quantities, which can reflect the change in wind speed since the start of the mutation (for example, the above initial moment), and the basic wind speed that already existed at the start of the mutation can be eliminated. This ensures that no matter what the basic wind speed is, the focus is always on the relative size of the cumulative change in the wind speed characteristic quantity, avoiding the difference in identifying wind shear conditions caused by different basic wind speeds, thereby being able to more accurately identify extreme wind shear conditions.

[0120] In step S130, the wind shear condition between the first incoming wind and the second incoming wind may be determined based on the first trend quantity and the second trend quantity.

[0121] In this step, when determining the first trend quantity and the second trend quantity, since the first trend quantity and the second trend quantity respectively represent the cumulative changes in the characteristic quantities of the first wind and the second wind within a preset time period, the wind shear condition between the current first wind and the second wind can be identified by comparing the first trend quantity and the second trend quantity.

[0122] As an example, step S130 may include the following steps:

[0123] like Figure 7 As shown, in step S710, a first difference between the first feature quantity and the second feature quantity may be determined based on an accumulation of the first feature quantity within a preset time period and an accumulation of the second feature quantity within a preset time period.

[0124] Specifically, the cumulative amount of the first characteristic quantity and the cumulative amount of the second characteristic quantity can respectively represent the cumulative wind energy of the first wind and the cumulative wind energy of the second wind. By determining the difference between the two, the energy difference between the winds at different positions of the impeller can be judged, thereby more accurately judging the degree of wind shear.

[0125] With the above Figure 5Taking equations (6) to (9) as examples, in an example where the first wind is the wind from the upper side of the impeller and the second wind is the wind from the lower side of the impeller, the cumulative amount of the first characteristic quantity within the preset time period can be expressed as The accumulation of the second characteristic quantity within the preset time period can be expressed as In this case, the first difference amount S v_diff It can be expressed by the following formula (10):

[0126]

[0127] Similarly, in the example where the first wind is the wind from the left side of the impeller and the second wind is the wind from the right side of the impeller, the cumulative amount of the first characteristic quantity within the preset time period can be expressed as The accumulation of the second characteristic quantity within the preset time period can be expressed as In this case, the first difference amount S h diff It can be expressed by the following formula (11):

[0128]

[0129] In step S720, the wind shear wind condition may be determined based on the first trend amount, the second trend amount, and the first difference amount.

[0130] Here, the first trend quantity and the second trend quantity can respectively characterize the accumulation of wind energy of the first wind and the second wind, and the first difference quantity can represent the difference between the accumulation of wind energy of the two winds. When these three parameters are known, it can be considered that the absolute wind conditions of the first wind and the second wind and the relative wind conditions between the two are mastered. Therefore, a suitable wind shear wind condition identification method can be selected for identification according to actual needs. Several examples of wind shear wind condition identification according to embodiments of the present disclosure are given below.

[0131] In one example, in step S720, preset conditions may be set for each of the first trend amount, the second trend amount, and the first difference amount. When the corresponding preset conditions are met, it may be considered that extreme wind shear conditions may have occurred.

[0132] For example, the presence of wind shear conditions can be determined in response to the first trend quantity satisfying the first preset condition, the second trend quantity satisfying the second preset condition, and the first difference quantity satisfying the third preset condition, or in response to the first difference quantity satisfying the third preset condition within a preset time length after the first trend quantity satisfies the first preset condition and the second trend quantity satisfies the second preset condition.

[0133] Here, the first preset condition may indicate that the cumulative amount of changes in the first characteristic quantity within the preset time period exceeds the design trend boundary of the wind turbine generator set; the second preset condition may indicate that the cumulative amount of changes in the second characteristic quantity within the preset time period exceeds the design trend boundary of the wind turbine generator set; the third preset condition may indicate that the difference between the first characteristic quantity and the second characteristic quantity exceeds the design difference boundary of the wind turbine generator set, wherein the numerical value of the design trend boundary of the first preset condition may be the reciprocal of the numerical value of the design trend boundary of the second preset condition.

[0134] Since wind shear conditions include positive shear conditions and negative shear conditions in the horizontal direction and positive shear conditions and negative shear conditions in the vertical direction, as an example, preset conditions may be set for different wind shear conditions, respectively.

[0135] As an example, in positive shear wind conditions, such as vertical positive shear wind conditions and horizontal positive shear wind conditions, the identification of wind shear can be explained by taking the extreme positive shear wind conditions in the extreme wind shear (EWS) wind conditions specified in the IEC-61400-1 standard as an example.

[0136] The first preset condition may be that the first trend amount is greater than the trend boundary, the second preset condition may be that the second trend amount is less than the opposite number of the trend boundary, and the third preset condition may be that the first difference amount is greater than the difference boundary.

[0137] For example, for vertical positive shear wind conditions, the trend boundary S can be set b_vp and the difference boundary S d_vp , these two boundary parameters are both positive. The above three preset conditions can be judged, specifically, they can be expressed as:

[0138]

[0139] When the above three preset conditions are met at the same time, or when the first preset condition and the second preset condition are met at the same time and the third preset condition is met within a future time length T, it can be determined as a vertical positive shear wind condition.

[0140] Similarly, for horizontal positive shear wind conditions, the trend boundary S can be set b_hp and the difference boundary S d_hp , these two boundary parameters are both positive. The above three preset conditions can be judged, specifically, they can be expressed as:

[0141]

[0142] When the above three preset conditions are met at the same time, or when the first preset condition and the second preset condition are met at the same time and the third preset condition is met within a future time length T, it can be determined as a horizontal positive shear wind condition.

[0143] As an example, in negative shear wind conditions, such as vertical negative shear wind conditions and horizontal negative shear wind conditions, the identification of wind shear can be explained by taking the extreme negative shear wind conditions in the EWS wind conditions specified in the IEC-61400-1 standard as an example.

[0144] The first preset condition may be that the first trend amount is less than the opposite number of the trend boundary, the second preset condition may be that the second trend amount is greater than the trend boundary, and the third preset condition may be that the first difference amount is less than the opposite number of the difference boundary.

[0145] For example, for vertical negative shear wind conditions, the trend boundary S can be set b_vn and the difference boundary S d_vn , these two boundary parameters are both positive. The above three preset conditions can be judged, specifically, they can be expressed as:

[0146]

[0147] When the above three preset conditions are met at the same time, or when the first preset condition and the second preset condition are met at the same time and the third preset condition is met within a future time length T, it can be determined as a vertical negative shear wind condition.

[0148] Similarly, for horizontal negative shear wind conditions, the trend boundary S can be set b_hn and the difference boundary S d_hn , these two boundary parameters are both positive. The above three preset conditions can be judged, specifically, they can be expressed as:

[0149]

[0150] When the above three preset conditions are met at the same time, or when the first preset condition and the second preset condition are met at the same time and the third preset condition is met within a future time length T, it can be determined as a horizontal negative shear wind condition.

[0151] In the above example, the time length T can be set according to actual needs. As an example, it can be defined according to the IEC61400-1 international standard. In the IEC 61400-1 international standard, the change period of the extreme wind shear model is 12 seconds. Therefore, the time length T can be set to 12 seconds.

[0152] By using the above-mentioned preset conditions to judge the wind shear condition, the wind shear condition can be comprehensively judged from two aspects, namely, the two trend quantities and the difference between the two trend quantities, so that the identification of the wind shear condition is more accurate.

[0153] Additionally or alternatively, in another example, in step S720, the wind shear condition may be determined in the following manner:

[0154] like Figure 8 As shown, in step S810, a second difference amount between the first trend amount and the second trend amount may be determined.

[0155] The above describes that the first difference amount is determined based on the first feature amount and the second feature amount. Here, the second difference amount may also be determined based on the first trend amount and the second trend amount as well as the first difference amount.

[0156] Still with the above Figure 5 Taking equations (6) to (9) as examples, in an example where the first wind is the wind from the upper side of the impeller and the second wind is the wind from the lower side of the impeller, the first trend quantity can be expressed as S high , the second trend quantity can be expressed as S low In this case, the second difference can be expressed as (S high -S low ).

[0157] Similarly, in the example where the first wind is the wind from the left side of the impeller and the second wind is the wind from the right side of the impeller, the first trend quantity can be expressed as S left , the second trend quantity can be expressed as S right In this case, the second difference can be expressed as (S left -S right ).

[0158] In step S820, a wind shear parameter may be determined based on the first difference amount and the second difference amount.

[0159] Here, the wind shear parameter may represent the degree of wind shear between the first wind and the second wind.

[0160] Still with the above Figure 5 Taking equations (6) to (9) as examples, in an example where the first wind is the wind from the upper side of the impeller and the second wind is the wind from the lower side of the impeller, the wind shear parameter S v It can be expressed by the following formula (12):

[0161] S v =(S high -S low )×S v_diff (12)

[0162] Similarly, in the example where the first wind is from the left side of the impeller and the second wind is from the right side of the impeller, the wind shear parameter S h It can be expressed by the following formula (13):

[0163] S h =(S left -S right )×S h_diff (13)

[0164] In step S830, the wind shear wind condition may be determined based on the wind shear parameter.

[0165] In this step, boundary conditions may be preset for the wind shear parameters, and when the wind shear parameters meet the boundary conditions, it may be determined to be a wind shear wind condition.

[0166] For example, different boundary conditions can be set for vertical wind shear conditions and horizontal wind shear conditions. Specifically, for vertical wind shear conditions, when the wind shear parameter S v Greater than the first boundary condition S vb In the case of , it can be determined as a vertical wind shear condition; for horizontal wind shear conditions, when the wind shear parameter S h Greater than the second boundary condition S hb In this case, it can be determined as a horizontal wind shear wind condition.

[0167] As an example, the boundary condition preset for the wind shear parameter may be related to the length Δt of the preset time period mentioned above, and the value of the boundary condition may be nonlinearly positively correlated with the length Δt of the preset time period.

[0168] In addition, as an example, the first difference amount and the second difference amount are both positive numbers, or the first difference amount and the second difference amount are both negative numbers. In this way, in calculating the wind shear parameter, the possibility of a negative value of the wind shear parameter can be eliminated by the same sign relationship between the first difference amount and the second difference amount, so that the wind shear parameter is always positive.

[0169] For example, for vertical positive shear wind conditions, the first trend quantity S high Greater than 0, the second trend quantity S low is less than 0, therefore, the first difference S v_diff is greater than 0, therefore, the wind shear parameter S v Greater than 0; for vertical negative shear wind conditions, the first trend quantity S high Less than 0, the second trend quantity S low is greater than 0, therefore, the first difference S v_diff is less than 0, therefore, the wind shear parameter S v It is also greater than 0. The same is true for horizontal positive shear wind conditions and horizontal negative shear wind conditions.

[0170] In this way, the same identification method can be used to identify positive shear wind conditions and negative shear wind conditions, which simplifies the identification logic of the wind condition identification process. For example, the number of set thresholds can be reduced, and only one threshold as a positive value is set to judge the size of the wind shear parameter.

[0171] According to the above-mentioned method for identifying wind shear conditions, the energy accumulation process can be considered through integration, and the wind shear parameters of positive shear wind conditions and negative shear wind conditions can be unified through the conversion method of wind shear parameters, thereby unifying the identification methods of positive shear wind conditions and negative shear wind conditions and reducing parameters.

[0172] It should be noted that although the calculation expressions of various parameters are shown in this article as examples, such as the above-mentioned formulas (1) to (13), they are not limited to the above-mentioned examples. For example, other calculation methods can be used for calculation, or variations of the above-mentioned expressions, multiple scaling, etc. can be used for calculation.

[0173] In step S140, pitch control may be performed on the wind turbine generator set based on the wind shear condition.

[0174] In this step, when it is identified that the wind is in a shear condition, pitch control can be used to achieve unit pitch control to alleviate the extreme load problem and clearance problem under the wind shear condition.

[0175] The following embodiments of the present disclosure provide several examples of performing pitch control on a wind turbine generator system based on wind shear conditions.

[0176] In one example, the pitch control of the wind turbine generator set can be performed in the following manner: Fig. 9 As shown, in step S910, an additional pitch angle may be determined based on wind shear conditions and wind speed related quantities; and in step S920, pitch control of the wind turbine generator may be performed based on the additional pitch angle.

[0177] Here, the wind speed related quantity may be a parameter related to the wind speed currently received by the wind turbine generator set, which may be, for example, the average wind speed, the pitch angle, etc., but is not limited thereto. The wind speed related quantity is used to characterize the magnitude or changing trend of the wind speed. The parameters obtained by statistical or other processing of the wind speed or the parameters that have a corresponding relationship with the wind speed can be used as wind speed related quantities.

[0178] In this step, pitch control can be performed based on two dimensions. Specifically, on the one hand, since the load and clearance results of the wind turbine generator set are different under different degrees of wind shear conditions, the wind shear parameter S v and wind shear parameter S h For example, the wind shear parameter S v and wind shear parameter Sh The larger it is, the greater the impact on the load and clearance of the wind turbine. On the other hand, the pitch control is also affected by the wind speed factor currently experienced by the wind turbine. Therefore, in this example, the idea of ​​fuzzy control can be adopted from a two-dimensional perspective to perform pitch control of the unit.

[0179] For example, Fig.10 As shown, in one dimension, the wind shear condition can be expressed by the wind shear parameter S v With the first boundary condition S vb The difference (S v -S vb ) and wind shear parameter S h With the second boundary condition S hb The difference (S h -S hb ) to indicate.

[0180] Here, the wind shear parameter S v Greater than the first boundary condition S vb The degree (S v -S vb ), the wind shear parameter is greater than the second boundary condition S hb The degree (S h -S hb ) to dynamically adjust the additional pitch angle Δθ, in (S v -S vb ) or (S h -S hb ) is less than or equal to 0, the additional pitch angle Δθ may be 0. However, it is not limited thereto. The wind shear condition may also be determined by the wind shear parameter S v and wind shear parameter S h To express, in this case, the wind shear parameter S v Less than or equal to the first boundary condition S vb and the wind shear parameter S h Less than or equal to the second boundary condition S hb In this case, the additional pitch angle Δθ can be 0.

[0181] Furthermore, in another dimension, the wind speed related quantity may be the average wind speed, and the additional pitch angle Δθ may be dynamically adjusted according to the average wind speed currently experienced by the wind turbine generator set.

[0182] For example, Fig.11 As shown, in one dimension, the wind shear condition can be expressed by the wind shear parameter S v With the first boundary condition S vb The difference (S v -S vb ) and wind shear parameter S h With the second boundary condition Shb The difference (S h -S hb ) to indicate.

[0183] In addition, in another dimension, the wind speed related quantity may be a pitch angle, and the additional pitch angle Δθ may be dynamically adjusted according to the pitch angle value of the current wind turbine. Here, the pitch angle is positively correlated with the current wind speed in the control of the wind turbine, so the greater the wind speed, the greater the pitch angle. Therefore, in this example, the pitch angle may be used as a wind speed related quantity.

[0184] In the above example, the load and clearance issues may be particularly prominent when the wind speed is near the rated wind speed, so if Fig.10 and Fig.11 As shown in FIG. 1 , when the average wind speed is close to the rated wind speed, or when the wind speed corresponding to the pitch angle is close to the rated wind speed, the additional pitch angle Δθ is large, that is, Fig.10 and Fig.11 The peak interval of the additional pitch angle Δθ.

[0185] When the additional pitch angle Δθ is determined, the additional pitch angle Δθ can be superimposed on the final pitch requirement of the wind turbine generator set, for example, it can be superimposed on the pitch angle determined by other control programs, thereby achieving the purpose of extreme load reduction and clearance protection under wind shear conditions.

[0186] In another example, the pitch control of a wind turbine generator set can be performed in the following manner:

[0187] like Fig.12 As shown, in step S1210, the wind speed characteristic quantity of the wind coming in front of the impeller can be determined based on the first characteristic quantity and the second characteristic quantity.

[0188] As an example, the wind speed characteristic quantity may be, for example, the average wind speed of the wind coming in front of the impeller. For example, the average value of the first characteristic quantity and the second characteristic quantity may be used as the wind speed characteristic quantity.

[0189] In step S1220, an additional pitch angle may be determined according to the extent to which the wind speed characteristic quantity deviates from the rated wind speed of the wind turbine generator set.

[0190] Under different wind speed conditions, when wind shear occurs, the impact on the unit is different. Generally speaking, the load reduction effect produced by control is higher near the rated wind speed. Therefore, the additional pitch angle can be determined according to the degree to which the wind speed characteristic quantity deviates from the rated wind speed of the wind turbine.

[0191] Here, the degree to which the wind speed characteristic quantity deviates from the rated wind speed may be negatively correlated with the additional pitch angle. When the wind speed characteristic quantity is near the rated wind speed, the additional pitch angle may be larger.

[0192] As an example, in step S1220, the additional pitch angle may be determined in the following manner:

[0193] like Fig.13 As shown, in step S1310, multiple wind speed intervals and candidate additional pitch angles corresponding to each wind speed interval may be determined based on the rated wind speed, cut-in wind speed, cut-out wind speed and a preset correction value of the wind turbine generator set.

[0194] In step S1320, a candidate additional pitch angle corresponding to a wind speed interval satisfied by the wind speed characteristic quantity may be determined as the additional pitch angle.

[0195] Here, the wind speed characteristic quantity may be divided into a plurality of wind speed intervals, and different intervals may correspond to different preset candidate additional pitch angles.

[0196] As an example, the plurality of wind speed intervals may include a first wind speed interval, a second wind speed interval, and a third wind speed interval, wherein the first wind speed interval may be determined based on a preset correction value and a rated wind speed, and includes the rated wind speed; the second wind speed interval may be determined based on a cut-in wind speed of the wind turbine generator set and the first wind speed interval, and is smaller than the first wind speed interval; the third wind speed interval may be determined based on a cut-out wind speed of the wind turbine generator set and the first wind speed interval, and is larger than the first wind speed interval. Here, the preset correction value may be determined according to actual needs or an empirical method, so as to be used to determine the first wind speed interval near the rated wind speed.

[0197] Here, the candidate additional pitch angle corresponding to the first wind speed interval may be greater than the candidate additional pitch angle corresponding to the third wind speed interval and the candidate additional pitch angle corresponding to the first wind speed interval. In this way, a larger additional pitch angle may be used when the wind speed condition is close to the rated wind speed, thereby improving the load reduction effect of pitch control.

[0198] Based on the above division of wind speed intervals, a nonlinear relationship curve between the wind speed characteristic and the additional pitch angle can be established. The curve can be expressed by the following formula (14):

[0199]

[0200] Among them, V0L represents the wind speed characteristic, V cutin Indicates the cut-in wind speed of the wind turbine, V rated Indicates the rated wind speed of the wind turbine generator set, V cutout represents the cut-out wind speed of the wind turbine generator set, v1 represents the preset first correction value, v2 represents the preset second correction value, θ represents the current pitch angle of the unit, θ0 represents the first pitch angle boundary, for example, it can be the minimum pitch angle of the unit, θ1 represents the second pitch angle boundary, Δθ maxHere, the second pitch angle boundary θ1 can be determined based on the corresponding pitch angle value when there is no risk in the whole machine load or clearance according to the non-open identification and protection scheme, and the maximum additional pitch demand Δθ max For example, it may be in the range of [0,5], and its unit is degree (deg). Although equation (14) shows the value of the additional pitch angle in each wind speed interval, it is not limited thereto and may also be set according to actual conditions.

[0201] As an example, the first correction value v1 and the second correction value v2 can be based on the whole machine development experience, such as v1∈[2,5], v2∈[2,5], and the unit can be meters per second (m / s). In addition, the first correction value and the second correction value can be the same or different, such as v1=3m / s and v2=5m / s.

[0202] In addition, the wind speed position where the load problem and / or clearance problem is the largest can be found based on the rated wind speed of the wind turbine generator set, and the first correction value v1 and the second correction value v2 can be set based on the wind speed position so that the wind speed position is included in the first wind speed interval. Taking the rated wind speed of 10m / s as an example, if the whole machine load problem occurs at a wind speed of 7m / s, v1 can be set to 4m / s to identify and control the wind speed in a specific range, and the method for selecting the second correction value v2 is similar.

[0203] For example, at the cut-in wind speed V cutin 3m / s, rated wind speed V rated The cut-out wind speed is 10m / s. cutout In the example where the first correction value v1 is 20 m / s, the first correction value v1 is 3 m / s, and the second correction value v2 is 5 m / s, the specific value can be as follows: Fig.14 The nonlinear relationship curve between the wind speed characteristic quantity and the additional pitch angle is shown.

[0204] Through the above method, the additional pitch angle can be determined according to the wind speed conditions, and pitch control can be performed to more precisely perform load protection and clearance protection under wind shear conditions.

[0205] In step S1230, pitch control may be performed on the wind turbine generator set based on the additional pitch angle.

[0206] After determining the additional pitch angle, the blades of the wind turbine can be controlled to perform the retracting action at a certain pitch rate, and the pitch angles of the three blades can be controlled from the current pitch angle θ to the position of θ+Δθ. After reaching the position of θ+Δθ, the pitch angle of the wind turbine can be limited, and the unit is not allowed to perform the opening action until the wind shear wind condition experiences and passes through the impeller surface of the wind turbine.

[0207] Through the above method, when a wind shear condition is identified, the additional pitch angle can be determined according to the wind speed conditions to perform variable pitch control. Since the changing trend of the wind speed is obtained in advance through the trend quantity, this control method has a time advance amount, which can effectively reduce the ultimate load of the wind turbine and alleviate the clearance.

[0208] Fig.15 , Fig.16 and Fig.17 The effects of using the pitch control method of a wind turbine generator set in a wind shear condition according to an exemplary embodiment of the present disclosure and not using the pitch control method are respectively shown.

[0209] Compared with not adopting the pitch control method, when the method according to the exemplary embodiment of the present disclosure is adopted, Fig.15 As shown, the load of the unit can be reduced; Fig.16 As shown, the headroom can be increased; Fig.17 As shown, the cabin acceleration can be reduced, thereby improving the stability of the unit.

[0210] According to the pitch control method of a wind turbine under wind shear conditions in an embodiment of the present disclosure, wind shear conditions can be accurately identified, and under extreme wind shear conditions, the pitch control of the wind turbine can be used to protect the entire machine, reduce the risk of blades sweeping the tower, and reduce the ultimate load of the wind turbine.

[0211] According to a second aspect of the present disclosure, a computer device is provided, comprising: at least one processor; and at least one memory storing computer executable instructions, wherein the computer executable instructions, when executed by the at least one processor, prompt the at least one processor to execute the pitch control method of a wind turbine generator set under wind shear conditions according to the exemplary embodiment of the present disclosure.

[0212] As an example, the computer device may be arranged in the wind turbine, or the computer device may be connected to a control system of the wind turbine.

[0213] As an example, the computer device can be a PC, a tablet device, a personal digital assistant, a smart phone, or other device capable of executing the above-mentioned instruction set. Here, the computer device is not necessarily a single electronic device, but can also be any device or circuit that can execute the above-mentioned instructions (or instruction sets) individually or jointly. The computer device can also be part of an integrated control system or system manager, or can be configured as a portable electronic device that is interconnected with a local or remote (e.g., via wireless transmission) interface.

[0214] In a computer device, a processor may include a central processing unit (CPU), a graphics processing unit (GPU), a programmable logic device, a dedicated processor system, a microcontroller or a microprocessor. As an example and not limitation, a processor may also include an analog processor, a digital processor, a microprocessor, a multi-core processor, a processor array, a network processor, etc.

[0215] The processor can execute instructions or codes stored in the memory, wherein the memory can also store data. Instructions and data can also be sent and received through the network via the network interface device, wherein the network interface device can adopt any known transmission protocol.

[0216] The memory may be integrated with the processor, for example, RAM or flash memory is arranged within an integrated circuit microprocessor or the like. In addition, the memory may include a separate device, such as an external disk drive, a storage array, or any other storage device that can be used by a database system. The memory and the processor may be operatively coupled, or may communicate with each other, such as through an I / O port, a network connection, etc., so that the processor can read files stored in the memory.

[0217] In addition, the computer device may also include a video display (such as a liquid crystal display) and a user interaction interface (such as a keyboard, a mouse, a touch input device, etc.) All components of the computer device may be connected to each other via a bus and / or a network.

[0218] According to a third aspect of the present disclosure, a wind turbine generator set is provided. The wind turbine generator set may include the computer device according to the embodiment of the present disclosure.

[0219] According to a fourth aspect of the present disclosure, a computer-readable storage medium is provided. When instructions in the computer-readable storage medium are executed by at least one processor, the at least one processor is prompted to execute the pitch control method of a wind turbine generator set under wind shear conditions according to the exemplary embodiment of the present disclosure.

[0220] The pitch control method of a wind turbine generator set under wind shear conditions according to an embodiment of the present disclosure can be written as a computer program and stored on a computer-readable storage medium. Examples of computer-readable storage media include: read-only memory (ROM), random access programmable read-only memory (PROM), electrically erasable programmable read-only memory (EEPROM), random access memory (RAM), dynamic random access memory (DRAM), static random access memory (SRAM), flash memory, non-volatile memory, CD-ROM, CD-R, CD+R, CD-RW, CD+RW, DVD-ROM, DVD-R, DVD+R, DVD-RW, DVD+RW, DVD-RAM, BD-ROM, BD-R, BD-R LTH, BD-RE, Blu-ray or optical disk storage, hard disk drive (HDD), solid state drive (SSD), card storage (such as, multimedia card, secure digital (SD) card or extreme digital (XD) card), magnetic tape, floppy disk, magneto-optical data storage device, optical data storage device, hard disk, solid state disk and any other device, any other device is configured to store computer program and any associated data, data files and data structures in a non-transitory manner and provide the computer program and any associated data, data files and data structures to a processor or computer so that the processor or computer can execute the computer program. In one example, the computer program and any associated data, data files and data structures are distributed on a networked computer system so that the computer program and any associated data, data files and data structures are stored, accessed and executed in a distributed manner by one or more processors or computers.

[0221] The specific implementation methods of the present disclosure have been described in detail above. Although some embodiments have been shown and described, those skilled in the art should understand that these embodiments may be modified and varied without departing from the principles and spirit of the present disclosure, the scope of which is defined by the claims and their equivalents. These modifications and variations should also be within the scope of protection of the claims of the present disclosure.

Claims

1. A method for controlling the pitch of a wind turbine generator set under wind shear conditions, characterized in that: The pitch control method comprises: Based on the wind speed data, determining a first characteristic value of a wind speed of a first incoming wind at an impeller of the wind turbine generator set and a second characteristic value of a wind speed of a second incoming wind at the impeller; Determine a first trend quantity of the first characteristic quantity and a second trend quantity of the second characteristic quantity respectively, wherein the first trend quantity represents a cumulative amount of changes in the first characteristic quantity within a preset time period before the first incoming wind reaches the impeller, and the second trend quantity represents a cumulative amount of changes in the second characteristic quantity within the preset time period; Determining a wind shear condition between the first incoming wind and the second incoming wind based on the first trend quantity and the second trend quantity; Based on the wind shear condition, pitch control is performed on the wind turbine generator set.

2. The pitch control method according to claim 1, characterized in that: The first trend amount and the second trend amount are determined by: determining the first trend amount based on the accumulation of the first feature amount within the preset time period and the accumulation of the first initial value of the first feature amount within the preset time period; determining the second trend amount based on the accumulation amount of the second feature amount within the preset time period and the accumulation amount of the second initial value of the second feature amount within the preset time period, The first initial value is a first characteristic value at a specific moment in the preset time period, and the second initial value is a second characteristic value at a specific moment in the preset time period.

3. The pitch control method according to claim 1, characterized in that: The determining of the wind shear condition between the first incoming wind and the second incoming wind based on the first trend quantity and the second trend quantity comprises: determining a first difference between the first feature quantity and the second feature quantity based on an accumulation amount of the first feature quantity within the preset time period and an accumulation amount of the second feature quantity within the preset time period; The wind shear wind condition is determined based on the first trend amount, the second trend amount, and the first difference amount.

4. The pitch control method according to claim 3, characterized in that: The determining the wind shear condition based on the first trend quantity, the second trend quantity and the first difference quantity comprises: determining a second difference amount between the first trend amount and the second trend amount; Determining a wind shear parameter based on the first difference and the second difference, wherein the wind shear parameter represents a degree of wind shear between the first incoming wind and the second incoming wind; Based on the wind shear parameter, the wind shear wind condition is determined.

5. The pitch control method according to claim 4, characterized in that: The first difference amount and the second difference amount are both positive numbers, or the first difference amount and the second difference amount are both negative numbers.

6. The pitch control method according to claim 3, characterized in that: The determining of the wind shear condition between the first incoming wind and the second incoming wind based on the first trend quantity and the second trend quantity comprises: In response to the first trend quantity satisfying a first preset condition, the first trend quantity satisfying a second preset condition and the first difference quantity satisfying a third preset condition, or in response to the first difference quantity satisfying the third preset condition within a preset time length after the first trend quantity satisfies the first preset condition and the first trend quantity satisfies the second preset condition, it is determined that a wind shear wind condition exists, The first preset condition indicates that the cumulative amount of the change of the first characteristic quantity within the preset time period exceeds the design trend boundary of the wind turbine generator set; The second preset condition indicates that the cumulative amount of change of the second characteristic quantity within the preset time period exceeds the design trend boundary of the wind turbine generator set; The third preset condition indicates that the difference between the first characteristic value and the second characteristic value exceeds the design difference boundary of the wind turbine generator set. Wherein, the numerical value of the design trend boundary of the first preset condition and the numerical value of the design trend boundary of the second preset condition are opposite to each other.

7. The pitch control method according to claim 1, characterized in that: The wind turbine generator set is subjected to pitch control in the following manner: Determining an additional pitch angle based on the wind shear wind condition and a wind speed related quantity, wherein the wind speed related quantity is a parameter related to the wind speed currently experienced by the wind turbine generator set; Based on the additional pitch angle, variable pitch control is performed on the wind turbine generator set.

8. The pitch control method according to claim 1, characterized in that: The first feature quantity and the second feature quantity are determined by: Acquiring wind speed data at multiple points on multiple paths from the incoming wind side to the impeller based on a wind measuring device; Determine the synthetic wind speed on each path at the current moment according to the wind speed data, the direction of each path, the distance of each of the multiple points from the impeller, and the wind speed processing parameter on the impeller at the current moment, wherein the wind speed processing parameter is determined based on the first feature quantity and the second feature quantity at the previous moment; The first feature amount and the second feature amount at the current moment are determined based on the composite wind speed at the current moment on each path.

9. The pitch control method according to claim 1, characterized in that: The wind turbine generator set is subjected to pitch control in the following manner: Determining a wind speed characteristic quantity of the wind coming in front of the impeller based on the first characteristic quantity and the second characteristic quantity; Determining an additional pitch angle according to the degree to which the wind speed characteristic quantity deviates from the rated wind speed of the wind turbine generator set; Based on the additional pitch angle, the wind turbine generator set is subjected to pitch control. The degree to which the wind speed characteristic quantity deviates from the rated wind speed is negatively correlated with the additional pitch angle.

10. The pitch control method according to claim 9, characterized in that: The step of determining the additional pitch angle according to the degree to which the wind speed characteristic quantity deviates from the rated wind speed of the wind turbine generator set comprises: Determining a plurality of wind speed intervals and candidate additional pitch angles corresponding to each wind speed interval based on the rated wind speed, the cut-in wind speed, the cut-out wind speed and a preset correction value of the wind turbine generator set; A candidate additional pitch angle corresponding to a wind speed interval satisfied by the wind speed characteristic quantity is determined as the additional pitch angle.

11. The pitch control method according to claim 10, characterized in that: The plurality of wind speed intervals include a first wind speed interval, a second wind speed interval and a third wind speed interval, The first wind speed interval is determined based on a preset correction value and the rated wind speed, and includes the rated wind speed; The second wind speed interval is determined based on the cut-in wind speed of the wind turbine generator set and the first wind speed interval, and is smaller than the first wind speed interval; The third wind speed interval is determined based on the cut-out wind speed of the wind turbine generator set and the first wind speed interval, and is greater than the first wind speed interval. The candidate additional pitch angle corresponding to the first wind speed interval is greater than the candidate additional pitch angle corresponding to the third wind speed interval and the candidate additional pitch angle corresponding to the first wind speed interval.

12. A computer device, characterized in that: include: at least one processor; at least one memory storing computer executable instructions, Wherein, when the computer executable instructions are executed by the at least one processor, the at least one processor is prompted to execute the pitch control method of a wind turbine generator set under wind shear conditions as described in any one of claims 1 to 11.

13. A wind turbine generator set, characterized in that: The wind turbine comprises the computer device according to claim 12.

14. A computer-readable storage medium, characterized in that: When the instructions in the computer-readable storage medium are executed by at least one processor, the at least one processor is prompted to execute the pitch control method of a wind turbine generator set under wind shear conditions as described in any one of claims 1 to 11.

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