Wind turbine and method for clearance control thereof

Abstract

Disclosed are a wind turbine generator and a method for controlling the clearance thereof, the method comprising: determining the rotation direction of the impeller of the wind turbine generator in response to the current clearance of the wind turbine generator being less than a safety clearance threshold; determining the yaw direction according to the rotation direction of the impeller and determining the yaw rate according to the clearance information of the wind turbine generator; and controlling the wind turbine generator to yaw the impeller upward in the yaw direction and at the yaw rate, so as to improve the clearance of the wind turbine generator.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to the field of wind power generation in general, and more particularly, to a wind turbine and a yaw control method thereof. BACKGROUND

[0002] In the early stage of the design of a wind turbine, the yaw angle and the pitch angle of the wind turbine are designed to ensure that the wind turbine has sufficient clearance. When an extreme situation occurs, such as an extreme wind speed, the pitch of the blades can be adjusted to reduce the thrust of the rotor to avoid excessive deformation of the blades and insufficient clearance, thereby avoiding the risk of tower strike. Currently, the pitch of the blades is triggered to reduce the thrust of the rotor by measuring the extreme situation (for example, by using a radar device) or by measuring the deformation of the blades (for example, by recording a video or using a laser device). When an extreme situation occurs, a faster pitch rate is usually desired to reduce the thrust of the rotor. However, a faster pitch rate can introduce a larger impact, which can increase the load on other parts of the wind turbine. SUMMARY

[0003] Embodiments of the present disclosure provide a wind turbine and a yaw control method thereof, which can effectively solve the problem that the yaw control method of the prior art can increase the load on the wind turbine.

[0004] In one general aspect, there is provided a yaw control method of a wind turbine, comprising: determining a rotor rotation direction of the wind turbine in response to a current clearance of the wind turbine being less than a safety clearance threshold; determining a yaw direction according to the rotor rotation direction and determining a yaw rate according to clearance information of the wind turbine; and controlling the wind turbine to yaw the rotor upward in the yaw direction and at the yaw rate to increase the clearance of the wind turbine.

[0005] Optionally, after controlling the wind turbine to yaw the rotor upward in the yaw direction and at the yaw rate, the yaw control method further comprises: detecting a first clearance of the wind turbine after yawing; maintaining a current yaw state of the wind turbine in response to the first clearance being greater than or equal to the safety clearance threshold; and increasing the yaw rate in response to the first clearance still being less than the safety clearance threshold.

[0006] Optionally, after controlling the wind turbine to yaw the rotor upward in the yaw direction and at the yaw rate, the yaw control method further comprises: detecting a second clearance of the wind turbine after yawing; and controlling the wind turbine to return to a normal operating state in response to the second clearance being greater than a predetermined clearance threshold, wherein the predetermined clearance threshold is greater than the safety clearance threshold.

[0007] Optionally, the yawing the wind turbine generator set to tilt the rotor in the yaw direction and at the yaw rate comprises: determining a predetermined yaw angle according to the clearance value of the current clearance and the average wind speed; and controlling the wind turbine generator set to yaw to tilt the rotor in the yaw direction and at the yaw rate, and to the predetermined yaw angle, so that the clearance of the wind turbine generator set is greater than or equal to the safety clearance threshold.

[0008] Optionally, the yaw rate is determined according to the clearance information of the wind turbine generator set, comprising: determining the yaw rate according to the clearance value of the current clearance; or determining the yaw rate according to the clearance reduction rate within a predetermined time period before the current time.

[0009] Optionally, the yaw rate is determined according to the clearance value of the current clearance, comprising: querying the yaw rate corresponding to the current clearance from a relationship database according to the clearance value of the current clearance, wherein the relationship database contains a mapping relationship between the clearance value and the yaw rate; or calculating the yaw rate corresponding to the current clearance in real time through the mapping relationship between the clearance value and the yaw rate according to the clearance value of the current clearance.

[0010] Optionally, the yaw direction is determined according to the rotor rotation direction, comprising: in the case that the wind turbine generator set is an upwind wind turbine generator set, when the rotor rotation direction is clockwise, determining the yaw direction as right turning of the wind turbine generator set; and when the rotor rotation direction is counterclockwise, determining the yaw direction as left turning of the wind turbine generator set, wherein the rotor rotation direction is determined according to the upwind observation.

[0011] Optionally, the yaw direction is determined according to the rotor rotation direction, comprising: in the case that the wind turbine generator set is a downwind wind turbine generator set, when the rotor rotation direction is clockwise, determining the yaw direction as left turning of the wind turbine generator set; and when the rotor rotation direction is counterclockwise, determining the yaw direction as right turning of the wind turbine generator set, wherein the rotor rotation direction is determined according to the upwind observation.

[0012] Optionally, the current clearance of the wind turbine generator set is determined to be less than the safety clearance threshold by one of the following ways: the deformation degree of the blade of the wind turbine generator set exceeds a safety deformation threshold; the load of the wind turbine generator set exceeds a safety load threshold; and the clearance value of the current clearance is less than the safety clearance threshold.

[0013] In another general aspect, a computer-readable storage medium storing instructions is provided, wherein the instructions, when executed by at least one computing device, cause the at least one computing device to perform any of the wind turbine generator clearance control methods described above.

[0014] In another general aspect, a wind turbine generator system is provided, including: a rotor; a yaw mechanism configured to cause the wind turbine generator system to perform a yaw action; a memory configured to store instructions; and a controller configured to execute the stored instructions stored in the memory to cause the yaw mechanism to perform the yaw control method of any of the wind turbine generator systems described above.

[0015] The wind turbine generator system and the yaw control method thereof according to the embodiments of the present disclosure, when the current clearance is less than the safety clearance threshold, determine a yaw direction according to a rotor rotation direction of the wind turbine generator system, determine a yaw rate according to the clearance information of the wind turbine generator system, and then yaw at the determined yaw direction and yaw rate, so that a gyroscopic moment generated by the yaw drives the rotor of the wind turbine generator system to pitch up, thereby improving the clearance of the wind turbine generator system and avoiding blade damage or tower collapse caused by tower sweeping. Therefore, by the present disclosure, the problem that the clearance control method in the prior art can cause the load of the wind turbine generator system to increase can be effectively solved.

[0016] Additional aspects and / or advantages of the general inventive concept will be set forth in part in the description that follows, and in part will be obvious from the description, or can be learned by practice of the general inventive concept. BRIEF DESCRIPTION OF DRAWINGS

[0017] The above and other objects and features of the embodiments of the present disclosure will become more apparent from the following description made with reference to the accompanying drawings, in which:

[0018] Figure 1 is a flowchart illustrating a yaw control method of a wind turbine generator system according to an embodiment of the present disclosure;

[0019] Figure 2 is a schematic diagram illustrating an upwind wind turbine generator according to an embodiment of the present disclosure;

[0020] Figure 3 is a schematic diagram illustrating a downwind wind turbine generator according to an embodiment of the present disclosure;

[0021] Figure 4 is a schematic diagram illustrating an execution logic according to an embodiment of the present disclosure;

[0022] Figure 5 is a schematic diagram illustrating a clearance change in a reference working condition according to an embodiment of the present disclosure;

[0023] Figure 6 is a schematic diagram illustrating a distance change from a blade to a tower in a comparative working condition according to an embodiment of the present disclosure;

[0024] Figure 7 is a schematic diagram illustrating a clearance change in a comparative working condition according to an embodiment of the present disclosure;

[0025] Figure 8 is a block diagram illustrating a yaw control device of a wind turbine generator system of the present disclosure. DETAILED DESCRIPTION

[0026] The following detailed description is presented to aid in understanding the method, apparatus and / or system described herein. It is not intended to limit the method, apparatus and / or system described herein to the details described. Rather, various changes, modifications and equivalents can be used, and substitutions can be made, without departing from the scope of the disclosure. For example, the order of the operations described herein can be altered, and additional operations can be added, without departing from the scope of the disclosure. Furthermore, features known to those in the art can be omitted for the sake of clarity and brevity.

[0027] The features described herein can be implemented in different forms and should not be construed as limited to the examples described herein. Rather, these examples are provided as a non-exhaustive list of a few of the many possible ways to implement the method, apparatus and / or system described herein.

[0028] As used herein, the term “and / or” includes any one of the associated listed items, as well as any combination of any two or more of the associated listed items.

[0029] Although terms such as “first,” “second,” and “third” can be used herein to describe various components, assemblies, regions, layers or sections, these components, assemblies, regions, layers or sections should not be limited to the terms. Rather, these terms are used only to distinguish one component, assembly, region, layer or section from another component, assembly, region, layer or section. Thus, a component, assembly, region, layer or section referred to as a first component, a first assembly, a first region, a first layer or a first section in the examples described herein can also be referred to as a second component, a second assembly, a second region, a second layer or a second section.

[0030] In the description, when an element (such as a layer, a region, or a substrate) is referred to as being “on,” “connected to,” or “coupled to” another element, it can be directly on, directly connected to, or directly coupled to the other element, or one or more other elements can be interposed therebetween. In contrast, when an element is referred to as being “directly on,” “directly connected to,” or “directly coupled to” another element, no other elements are interposed therebetween.

[0031] The terminology used herein is for the purpose of describing various examples only and is not intended to be limiting of the disclosure. As used herein, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms "comprises," "comprising," "includes," "including" and "has" are not intended to exclude many existing

[0032] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs when read in light of the entire disclosure. The terminology used, such as that found in the typical dictionary, is to be interpreted as consistently as the context will allow with the meaning to be understood by those of skill in the related art and the disclosure, and is not to be interpreted in an idealized or overly formal sense.

[0033] Further, in the description of the examples, detailed descriptions of well-known related structures or functions are omitted when it is deemed that such detailed description will cause ambiguous interpretation of the present disclosure.

[0034] The present disclosure provides a wind turbine generator and a clearance control method thereof, which can solve the above-mentioned problems. The clearance control method of the wind turbine generator of the present disclosure can be applied to a server, a controller of a single wind turbine generator, or a general controller of a wind farm. The present disclosure does not limit the server, the controller, and the wind turbine generator to be connected by wireless or wired connection. The above-mentioned server can be one server, a server cluster composed of several servers, a cloud computing platform, or a virtualization center. Hereinafter, the controller of a single wind turbine generator will be described as an example.

[0035] The controller determines a rotation direction of the impeller of the wind turbine generator in response to the current clearance of the wind turbine generator being less than a safety clearance threshold value, determines a yaw direction according to the rotation direction of the impeller, and determines a yaw rate according to the clearance information of the wind turbine generator. The controller controls the wind turbine generator to yaw the impeller upward in the yaw direction and at the yaw rate to improve the clearance of the wind turbine generator, thereby avoiding damage to the blades or collapse of the tower caused by the wind turbine generator sweeping the tower.

[0036] Hereinafter, the wind turbine generator and the clearance control method thereof of the present disclosure will be described in detail with reference to the accompanying drawings.

[0037] The present disclosure proposes a wind turbine generator and a clearance control method thereof, Figure 1 is a flowchart showing a clearance control method of a wind turbine generator according to an embodiment of the present disclosure. Referring to Figure 1 , the clearance control method of the wind turbine generator includes the following steps:

[0038] In step S101, the rotating direction of the impeller of the wind turbine is determined in response to the current clearance of the wind turbine being less than a safety clearance threshold.

[0039] The rotating direction of the impeller of the wind turbine can be detected by a sensor, can be calculated by analyzing and calculating hardware feedback information, or can be observed by a person, and the present disclosure does not limit the rotating direction of the impeller of the wind turbine, which can include clockwise, counterclockwise, and the like. The present disclosure also does not limit the safety clearance threshold, which can be set as needed.

[0040] As an example, in the event of an extreme situation (such as a gust), the operating condition of the wind turbine can be detected periodically or in real time, and once it is detected that the clearance of the wind turbine is less than the safety clearance threshold, the operation of determining the rotating direction of the impeller of the wind turbine is performed. The determination process of the rotating direction of the impeller of the wind turbine will be described later, and will not be described here.

[0041] According to an embodiment of the present disclosure, the current clearance of the wind turbine being less than the safety clearance threshold can be determined in one of the following ways: the deformation degree of the blade of the wind turbine exceeds a safety deformation threshold; the load of the wind turbine exceeds a safety load threshold; and the clearance value of the current clearance is less than the safety clearance threshold. According to the present embodiment, the way of determining that the current clearance of the wind turbine is less than the safety clearance threshold can be flexibly set, thereby meeting various user needs.

[0042] The safety deformation threshold, the safety load threshold, and the safety clearance threshold can be set as needed, and the present disclosure does not limit them. The deformation degree of the blade of the wind turbine can be detected by a sensor, can be calculated by analyzing and calculating hardware feedback information, or can be observed by a person, and the present disclosure does not limit it. The load of the wind turbine can also be detected by a sensor, and the present disclosure does not limit it. The clearance value of the clearance of the wind turbine can also be detected by a sensor, and the present disclosure does not limit it.

[0043] As an example, in the event of an extreme situation (such as a gust), the operating condition of the wind turbine can be detected periodically or in real time, and once it is detected that the clearance of the wind turbine is less than the safety clearance threshold, the operation of determining the rotating direction of the impeller of the wind turbine is performed. The determination process of the rotating direction of the impeller of the wind turbine will be described later, and will not be described here. As an example, in the event of an extreme situation (such as a gust), the operating condition of the wind turbine can be detected periodically or in real time, and once it is detected that the clearance of the wind turbine is less than the safety clearance threshold, the operation of determining the rotating direction of the impeller of the wind turbine is performed. The determination process of the rotating direction of the impeller of the wind turbine will be described later, and will not be described here.

[0044] In step S102, the yaw direction is determined according to the rotor rotation direction, and the yaw rate is determined according to the clearance information of the wind turbine generator.

[0045] The determination of the rotor rotation direction is related to the type of the wind turbine generator, for example, for an upwind wind turbine generator, the rotor rotation direction is determined by observing in the upwind direction, and for a downwind wind turbine generator, the rotor rotation direction is also determined by observing in the upwind direction. The determination process of the yaw direction will be introduced from the two types of wind turbine generators respectively as follows:

[0046] According to an embodiment of the present disclosure, the yaw direction is determined according to the rotor rotation direction, which can include: in the case of the wind turbine generator being an upwind wind turbine generator, when the rotor rotation direction is clockwise, determining the yaw direction to be right rotation of the wind turbine generator; when the rotor rotation direction is counterclockwise, determining the yaw direction to be left rotation of the wind turbine generator, wherein the rotor rotation direction is determined by observing in the upwind direction.

[0047] According to an embodiment of the present disclosure, the yaw direction is determined according to the rotor rotation direction, which can also include: in the case of the wind turbine generator being a downwind wind turbine generator, when the rotor rotation direction is clockwise, determining the yaw direction to be left rotation of the wind turbine generator; when the rotor rotation direction is counterclockwise, determining the yaw direction to be right rotation of the wind turbine generator, wherein the rotor rotation direction is determined by observing in the upwind direction.

[0048] According to the above embodiments, the type of the wind turbine generator is distinguished, i.e. the upwind wind turbine generator and the downwind wind turbine generator, which can ensure that the determined yaw direction drives the rotor of the wind turbine generator to tilt upward rather than downward, thereby avoiding the tower scanning of the wind turbine generator leading to blade damage or tower collapse.

[0049] As an example, in the case of the wind turbine generator being an upwind wind turbine generator, if the rotor rotation direction of the wind turbine generator is determined to be clockwise by observing in the upwind direction, then the yaw direction should be right rotation of the wind turbine generator; if the rotor rotation direction of the wind turbine generator is determined to be counterclockwise by observing in the upwind direction, then the yaw direction should be left rotation of the wind turbine generator. Only in this way, the determined yaw direction can drive the rotor of the wind turbine generator to tilt upward rather than downward, thereby avoiding the tower scanning of the wind turbine generator leading to blade damage or tower collapse.

[0050] As an example, in the case of the wind turbine is a downwind wind turbine, if the determination of the direction of rotation of the impeller of the wind turbine is clockwise in the way from the downwind to the wind turbine, then the yaw direction should be that the wind turbine turns left; if the determination of the direction of rotation of the impeller of the wind turbine is counterclockwise in the way from the downwind to the wind turbine, then the yaw direction should be that the wind turbine turns right. Similarly, the yaw direction thus determined can drive the impeller of the wind turbine to pitch up instead of pitch down, avoiding the tower-sweeping of the wind turbine leading to blade damage or tower collapse.

[0051] It should be noted that the upwind wind turbine refers to the wind turbine in which the wind first passes through the rotating impeller and then passes through the horizontal shaft of the tower; the downwind wind turbine refers to the wind turbine in which the wind first passes through the tower and then passes through the impeller.

[0052] The yaw rate in the above step S102 can be determined according to the clearance value of the current clearance, or can be determined according to the clearance reduction rate within a predetermined time length, and the present disclosure does not limit this. The yaw rate determination process will be introduced from the two ways respectively as follows:

[0053] According to the embodiment of the present disclosure, the determination of the yaw rate according to the clearance information of the wind turbine can include: determining the yaw rate according to the clearance value of the current clearance; or, determining the yaw rate according to the clearance reduction rate within a predetermined time length before the current time. According to the present embodiment, the corresponding yaw rate can be determined by both the clearance value and the clearance reduction rate, which improves the flexibility of operation, and the determination of the yaw rate according to the clearance reduction rate within a predetermined time length can avoid the yawing caused by the rapid change of the clearance, which leads to the fact that the pitch-up cannot keep up with the rhythm of the change of the clearance, resulting in the danger of the tower-sweeping of the wind turbine; and the determination of the yaw rate according to the clearance value of the current clearance can simplify the determination process without the need to additionally calculate the clearance reduction rate.

[0054] According to the embodiment of the present disclosure, the above determination of the yaw rate according to the clearance value of the current clearance can be: according to the clearance value of the current clearance, querying the yaw rate corresponding to the current clearance from a relationship database, wherein the relationship database contains the mapping relationship between the clearance value and the yaw rate; or, according to the clearance value of the current clearance, calculating in real time the yaw rate corresponding to the current clearance through the mapping relationship between the clearance value and the yaw rate. According to the present embodiment, the mapping relationship between the clearance value and the yaw rate is stored in advance, so that when the clearance value of the clearance is known, the corresponding yaw rate can be directly and quickly queried from the relationship database in which the mapping relationship is stored, or the corresponding accurate yaw rate can be obtained through real-time calculation of the mapping relationship.

[0055] As an example, a plurality of clearance values and yaw rates corresponding to each of the clearance values can be obtained through experiments, and the obtained plurality of clearance values and yaw rates corresponding to each of the clearance values can be stored in a relationship database, so that when the clearance value of the clearance is known, the corresponding yaw rate can be directly and quickly queried through the relationship database.

[0056] As an example, after obtaining a plurality of clearance values and yaw rates corresponding to each of the clearance values, a relationship model can be determined based on the mapping relationship between the clearance values and the corresponding yaw rates, and when the clearance value of the clearance is known, the corresponding accurate yaw rate can be calculated in real time according to the relationship model. Specifically, the plurality of clearance values and the yaw rates corresponding to each of the clearance values are taken as training samples, the initial relationship model is trained through the training samples to obtain a trained relationship model, and then when the clearance value of the clearance is known, the clearance value is input into the relationship model to calculate the yaw rate corresponding to the clearance value in real time.

[0057] According to the embodiments of the present disclosure, the yaw rate determined according to the clearance reduction rate in the predetermined time period before the current time can be querying the yaw rate corresponding to the current clearance reduction rate from the relationship database according to the clearance reduction rate in the predetermined time period before the current time, wherein the relationship database contains the mapping relationship between the clearance reduction rate in the predetermined time period and the yaw rate; or, the yaw rate corresponding to the current clearance can be calculated in real time through the mapping relationship between the clearance reduction rate in the predetermined time period and the yaw rate according to the clearance reduction rate in the predetermined time period before the current time.

[0058] As an example, a plurality of predetermined time period clearance reduction rates and yaw rates corresponding to each of the clearance reduction rates can be obtained through experiments, and the obtained plurality of clearance reduction rates and yaw rates corresponding to each of the clearance reduction rates can be stored in a relationship database, so that when the clearance reduction rate in the predetermined time period before the current time is known, the corresponding yaw rate can be directly and quickly queried through the relationship database.

[0059] As an example, after obtaining a plurality of predetermined time period clearance reduction rates and yaw rates corresponding to each of the clearance reduction rates, a relationship model can be determined based on the mapping relationship between the clearance reduction rates and the corresponding yaw rates, and when the clearance reduction rate in the predetermined time period before the current time is known, the corresponding accurate yaw rate can be calculated in real time according to the relationship model. Specifically, the plurality of predetermined time period clearance reduction rates and the yaw rates corresponding to each of the clearance reduction rates are taken as training samples, the initial relationship model is trained through the training samples to obtain a trained relationship model, and then when the clearance reduction rate in the predetermined time period before the current time is known, the clearance reduction rate is input into the relationship model to calculate the yaw rate corresponding to the clearance reduction rate in real time.

[0060] It should be noted that the predetermined time length between the current time can be the predetermined time length of the most adjacent current time, or the predetermined time length of a period of time before the current time. For example, assuming that the current time is 3 o'clock and the predetermined time length is 2 hours, the predetermined time length before the current time can be from 1 o'clock to 3 o'clock, or from 12 o'clock to 2 o'clock, or from 12:30 to 2:30. The present disclosure does not limit this.

[0061] In step S103, the wind turbine generator set is controlled to yaw in the yaw direction and the yaw rate to tilt the blades upward to improve the clearance of the wind turbine generator set.

[0062] The above-mentioned yaw rate can be determined according to the clearance value of the current clearance, or according to the clearance reduction rate within the predetermined time length of the clearance. Regardless of which way the yaw rate is determined, the wind turbine generator set can be subsequently controlled to yaw in the yaw direction and the yaw rate to tilt the blades upward to improve the clearance of the wind turbine generator set.

[0063] According to an embodiment of the present disclosure, after the wind turbine generator set is controlled to yaw in the yaw direction and the yaw rate to tilt the blades upward, the first clearance of the wind turbine generator set after yawing can be detected; in response to the first clearance being greater than or equal to the safety clearance threshold, the current yaw state of the wind turbine generator set is maintained; and in response to the first clearance still being less than the safety clearance threshold, the yaw rate is increased. According to the present embodiment, after yawing, the clearance can be continuously monitored. When the clearance after yawing reaches the safety clearance threshold, the current yaw state of the wind turbine generator set can be maintained. If the clearance after yawing is still less than the safety clearance threshold, the yaw rate is increased to increase the blade tilt angle, thereby improving the clearance of the wind turbine generator set and avoiding the risk of tower scanning of the wind turbine generator set when the adjustment does not reach the safety clearance threshold.

[0064] As an example, after the wind turbine generator set is controlled to yaw in the yaw direction and the yaw rate to tilt the blades upward, the clearance of the wind turbine generator set after yawing can be periodically or in real time. When the clearance after yawing is greater than or equal to the safety clearance threshold, the current yaw state of the wind turbine generator set can be maintained without further yawing at a larger angle, thereby avoiding the loss of power generation efficiency caused by long-term yawing at a large angle.

[0065] As an example, after the wind turbine generator set is controlled to yaw in the yaw direction and the yaw rate to tilt the blades upward, the clearance of the wind turbine generator set after yawing can be periodically or in real time. When the clearance after yawing is still less than the safety clearance threshold, the yaw rate can be increased to speed up the yawing, thereby avoiding the risk of tower scanning of the wind turbine generator set when the clearance does not reach the safety clearance threshold for a long time.

[0066] According to an embodiment of the present disclosure, after the wind turbine generator set is controlled to yaw the blade up in the yaw direction and at the yaw rate, the second clearance of the wind turbine generator set after yawing can be detected; and in response to the second clearance being greater than the predetermined clearance threshold, the wind turbine generator set is controlled to return to the normal operating state, wherein the predetermined clearance threshold is greater than the safety clearance threshold.

[0067] According to the present embodiment, when the clearance of the wind turbine generator set after yawing is greater than the predetermined clearance threshold (e.g., no longer in an extreme situation), the wind turbine generator set does not need to yaw again and can return to the normal operating state, thereby avoiding the loss of power generation efficiency caused by long-time yawing.

[0068] The predetermined clearance threshold can be set as needed, and the present disclosure does not limit this. However, the predetermined clearance threshold must be greater than the safety clearance threshold, because the predetermined clearance threshold is used to indicate that the clearance is already large enough and is no longer at the safety limit of the clearance. Even if the subsequent clearance is slightly smaller, the wind turbine generator set will not have the risk of tower scanning.

[0069] The second clearance and the first clearance are both clearances of the wind turbine generator set after yawing to tilt the blade up. The two clearances can be detected at the same time or at different times, and the present disclosure does not limit this.

[0070] For example, if the first clearance and the second clearance are detected at different times, the second clearance can be detected after the first clearance. For example, after the first yawing, the detected first clearance is greater than or equal to the safety clearance threshold, the current yawing state of the wind turbine generator set is maintained, and when the extreme situation becomes weaker, the clearance gradually recovers. At this time, the clearance can be detected in real time, i.e., the second clearance, until the second clearance is greater than the predetermined clearance threshold, and the wind turbine generator set is controlled to return to the normal operating state. That is, the second clearance is detected when the clearance gradually recovers, and the first clearance is detected after the first yawing. For another example, after the first yawing, the detected first clearance is still less than the safety clearance threshold, the yawing rate is increased, and after yawing at the increased yawing rate, the clearance can also be detected in real time, i.e., the second clearance, until it is found that the second clearance is greater than the predetermined clearance threshold, and the wind turbine generator set is controlled to return to the normal operating state. That is, the second clearance is detected after the yawing rate is increased, and the first clearance is detected after the first yawing.

[0071] For example, after the wind turbine generator set is yawed to tilt the blade up in the yaw direction and at the yaw rate, the clearance of the wind turbine generator set after yawing can be detected periodically or in real time. When the clearance after yawing is greater than the predetermined clearance threshold, it indicates that the clearance is large enough, the wind turbine generator set does not need to yaw again, and can return to the normal operating state, thereby avoiding the loss of power generation efficiency caused by long-time yawing.

[0072] According to an embodiment of the present disclosure, the yawing the rotor upwind in the yaw direction and at the yaw speed can include: determining a predetermined yaw angle according to the clearance value of the current clearance and the average wind speed; and controlling the wind turbine to yaw in the yaw direction and at the yaw speed to yaw the rotor upwind to the predetermined yaw angle, so that the clearance of the wind turbine is greater than or equal to the safety clearance threshold. According to the present embodiment, when the wind turbine is yawed in the appropriate yaw direction and at the appropriate yaw speed, the yaw angle at which the clearance reaches the safety clearance threshold is also determined, so that the clearance of the wind turbine after yawing can be ensured to not be less than the safety clearance threshold, and other operations when the clearance after yawing is less than the safety clearance threshold are avoided, thereby reducing the complexity of the operation.

[0073] The predetermined yaw angle can be obtained through experiments. For example, a plurality of clearance values, average wind speeds and corresponding yaw angles can be obtained through experiments, and the plurality of clearance values, average wind speeds and corresponding yaw angles obtained are stored in a predetermined database. Thus, when the clearance value of the current clearance and the average wind speed at the time are known, the corresponding yaw angle can be directly and quickly queried from the predetermined database. The predetermined yaw angle can also be obtained in real time. For example, after a plurality of clearance values, average wind speeds and corresponding yaw angles are obtained through experiments, a yaw angle determination model is determined based on the mapping relationship between the plurality of clearance values, average wind speeds and corresponding yaw angles. When the clearance value of the current clearance and the average wind speed at the time are known, the corresponding accurate yaw angle can be calculated in real time according to the yaw angle determination model. Specifically, the plurality of clearance values, average wind speeds and corresponding yaw angles are taken as training samples, the initial yaw angle determination model is trained through the training samples to obtain a trained yaw angle determination model, and then when the clearance value of the current clearance and the average wind speed at the time are known, the clearance value and the average wind speed are input into the yaw angle determination model to calculate the predetermined yaw angle corresponding to the clearance value in real time.

[0074] For example, after the yaw direction and the yaw speed are determined, the predetermined yaw angle can be determined according to the clearance value of the current clearance and the average wind speed, so that the wind turbine can be controlled to yaw in the yaw direction and at the yaw speed to yaw the rotor upwind to the determined predetermined yaw angle, so that the clearance of the wind turbine is greater than or equal to the safety clearance threshold.

[0075] According to an embodiment of the present disclosure, the present disclosure provides a wind turbine, which includes: a rotor; a yaw mechanism configured to yaw the wind turbine; a memory configured to store instructions; and a controller configured to execute the stored instructions stored in the memory to cause the yaw mechanism to perform the clearance control method of any of the wind turbines described above.

[0076] The wind turbine in the above embodiments can be a two-blade wind turbine, a three-blade wind turbine, or a wind turbine with any other number of blades, and the present disclosure is not limited in this regard.

[0077] The following will be described by taking a two-blade wind turbine as an example.

[0078] According to embodiments of the present disclosure, the present disclosure provides a wind turbine, comprising: an impeller, the impeller comprising a first blade and a second blade; a yaw mechanism configured to cause the wind turbine to perform a yaw action; a memory configured to store instructions; and a controller configured to execute the stored instructions stored in the memory, causing the yaw mechanism to perform the above-mentioned yaw control method of any wind turbine.

[0079] As an example, as shown in FIG. 1, a wind turbine is taken as an example from the upwind direction, and the direction of rotation of the impeller is observed from the upwind direction, and it is determined that the direction of rotation of the impeller of the wind turbine is clockwise. When an extreme situation (such as a gust) occurs, the yaw rate can be determined according to the current clearance value, so that the yaw mechanism drives the wind turbine to rotate to the right at the determined yaw rate. At this time, the gyroscopic moment generated by yawing drives the impeller to lift its head, so that the impeller is away from the tower, the clearance becomes larger, and the risk of tower sweeping of the wind turbine is reduced. Figure 2 As an example, as shown in FIG. 1, a wind turbine is taken as an example from the upwind direction, and the direction of rotation of the impeller is observed from the upwind direction, and it is determined that the direction of rotation of the impeller of the wind turbine is clockwise. When an extreme situation (such as a gust) occurs, the yaw rate can be determined according to the current clearance value, so that the yaw mechanism drives the wind turbine to rotate to the right at the determined yaw rate. At this time, the gyroscopic moment generated by yawing drives the impeller to lift its head, so that the impeller is away from the tower, the clearance becomes larger, and the risk of tower sweeping of the wind turbine is reduced.

[0080] As an example, as shown in FIG. 1, a wind turbine is taken as an example from the upwind direction, and the direction of rotation of the impeller is observed from the upwind direction, and it is determined that the direction of rotation of the impeller of the wind turbine is clockwise. When an extreme situation (such as a gust) occurs, the yaw rate can be determined according to the current clearance value, so that the yaw mechanism drives the wind turbine to rotate to the right at the determined yaw rate. At this time, the gyroscopic moment generated by yawing drives the impeller to lift its head, so that the impeller is away from the tower, the clearance becomes larger, and the risk of tower sweeping of the wind turbine is reduced. Figure 3 As an example, as shown in FIG. 1, a wind turbine is taken as an example from the upwind direction, and the direction of rotation of the impeller is observed from the upwind direction, and it is determined that the direction of rotation of the impeller of the wind turbine is clockwise. When an extreme situation (such as a gust) occurs, the yaw rate can be determined according to the current clearance value, so that the yaw mechanism drives the wind turbine to rotate to the right at the determined yaw rate. At this time, the gyroscopic moment generated by yawing drives the impeller to lift its head, so that the impeller is away from the tower, the clearance becomes larger, and the risk of tower sweeping of the wind turbine is reduced.

[0081] It should be noted that the wind turbine of the present disclosure can also include a conventional yaw system. When the yaw mechanism of the present disclosure is not started, the yaw operation is performed through the yaw system as before. However, when the scheme of the present disclosure is executed, that is, when the yaw mechanism of the present disclosure is started, the conventional yaw system included in the wind turbine will be turned off, and the yaw mechanism of the present disclosure will preferentially execute the scheme of the present disclosure. The specific execution logic can be as shown in FIG. 2. Figure 4As shown: if the technical solution of the present disclosure is not enabled, that is, the yaw control clearance is not passed through, if an extreme situation occurs, the yaw operation will be performed through the conventional yaw system, at this time, the yaw direction and the yaw rate also need to be determined, but it will not be based on the clearance calculation, generally, the change of the wind direction is transmitted to the processor of the yaw motor control loop of the yaw system through the wind sensor, the yaw direction and the yaw angle are determined after judgment, and finally the purpose of wind-against is achieved; if the technical solution of the present disclosure is enabled, the yaw mechanism of the present disclosure is used to make the wind turbine generator set yaw, at this time, the yaw direction and the yaw rate also need to be determined, but here it needs to be determined based on the clearance related information to avoid the problem caused by too small clearance.

[0082] The following analyzes the clearance change under the conditions of left turn or right turn of the wind turbine generator set when the direction of rotation of the impeller of the wind turbine generator set is clockwise:

[0083] Reference condition: it is assumed that the wind speed starts to appear gust at 40s, the wind speed gradually increases, the rotation speed and the pitch angle of the wind turbine generator set start to increase after a few seconds delay, and the clearance reaches the minimum value in the process, as shown in Figure 5 .

[0084] Comparative condition (execute left turn or right turn condition): it is assumed that the wind speed starts to appear gust at 40s, the influence of the clearance will lag for a few seconds, the clearance is large before the influence of the gust (that is, the distance between the blade and the tower is far, as shown in Figure 6 before the influence of the gust), the blade clearance becomes small in the middle of the influence of the gust, when it is detected that the clearance is less than the safety clearance threshold or the clearance continuously decreases (such as the deformation degree of the blade continuously increases or the load continuously increases), the yaw direction can be determined according to the direction of rotation of the impeller, the yaw rate is determined based on the clearance information, the yaw of the wind turbine generator set is triggered to generate a favorable gyroscopic moment, and the further deterioration of the clearance is avoided, as shown in Figure 6 in the middle of the influence of the gust, wherein the blue solid line (clearance 1) represents the clearance when the wind turbine generator set does not rotate at the moment when the clearance is minimum, the green solid line (clearance 2) represents the clearance when the wind turbine generator set turns right at the moment when the clearance is minimum, the black solid line (clearance 3) represents the clearance when the wind turbine generator set turns left at the moment when the clearance is minimum, and further, it can be seen from Figure 6 after the influence of the gust that the clearance is recovered better after the scheme of the present disclosure is adopted, that is, the clearance is relatively larger.

[0085] Specifically, if the wind turbine generator set turns right at the moment when the clearance is minimum, the blade clearance is improved (such as Figure 7 clearance 1 in the middle) under the influence of the gyroscopic moment; if the wind turbine generator set turns left at the moment when the clearance is minimum, the blade clearance is deteriorated (such as Figure 7the middle clearance 3) if the wind turbine set does not rotate at the moment when the clearance is the smallest, the blade clearance is also deteriorated, but the deterioration degree is less than the case that the wind turbine set rotates to the left (as shown in Figure 7 the middle clearance 2).

[0086] Figure 8 is a block diagram showing a clearance control device of a wind turbine set according to the present disclosure, as shown, the device comprises a rotor rotation direction determination unit 80, a yaw direction and yaw rate determination unit 82 and a yaw unit 84. Figure 8

[0087] The rotor rotation direction determination unit 80 is configured to determine the rotor rotation direction of the wind turbine set in response to the current clearance of the wind turbine set being less than the safety clearance threshold; the yaw direction and yaw rate determination unit 82 is configured to determine the yaw direction according to the rotor rotation direction and determine the yaw rate according to the clearance information of the wind turbine set; and the yaw unit 84 is configured to control the wind turbine set to yaw the rotor up in the yaw direction and at the yaw rate to improve the clearance of the wind turbine set.

[0088] According to an embodiment of the present disclosure, the yaw unit 84 is further configured to detect a first clearance of the wind turbine set after the wind turbine set is controlled to yaw the rotor up in the yaw direction and at the yaw rate; maintain the current yaw state of the wind turbine set in response to the first clearance being greater than or equal to the safety clearance threshold; and increase the yaw rate in response to the first clearance still being less than the safety clearance threshold.

[0089] According to an embodiment of the present disclosure, the yaw unit 84 is further configured to detect a second clearance of the wind turbine set after the wind turbine set is controlled to yaw the rotor up in the yaw direction and at the yaw rate; and control the wind turbine set to return to the normal operation state in response to the second clearance being greater than a predetermined clearance threshold, wherein the predetermined clearance threshold is greater than the safety clearance threshold.

[0090] According to an embodiment of the present disclosure, the yaw unit 84 is further configured to determine a predetermined yaw angle according to the clearance value of the current clearance and the average wind speed; control the wind turbine set to yaw the rotor up in the yaw direction and at the yaw rate, and yaw to the predetermined yaw angle, so that the clearance of the wind turbine set is greater than or equal to the safety clearance threshold.

[0091] According to an embodiment of the present disclosure, the yaw direction and yaw rate determination unit 82 is further configured to determine the yaw rate according to the clearance value of the current clearance; or determine the yaw rate according to the clearance reduction rate within a predetermined time length before the current time.

[0092] ​According to an embodiment of the present disclosure, the yaw direction and yaw rate determining unit 82 is further configured to, in the case that the wind turbine generator set is an upwind wind turbine generator set, determine the yaw direction as right turning of the wind turbine generator set when the blade rotation direction is clockwise, and determine the yaw direction as left turning of the wind turbine generator set when the blade rotation direction is counterclockwise, wherein the blade rotation direction is determined by observing in the upwind direction.

[0093] According to an embodiment of the present disclosure, the yaw direction and yaw rate determining unit 82 is further configured to, in the case that the wind turbine generator set is an upwind wind turbine generator set, determine the yaw direction as right turning of the wind turbine generator set when the blade rotation direction is clockwise, and determine the yaw direction as left turning of the wind turbine generator set when the blade rotation direction is counterclockwise, wherein the blade rotation direction is determined by observing in the upwind direction.

[0094] According to an embodiment of the present disclosure, the yaw direction and yaw rate determining unit 82 is further configured to, according to the clearance value of the current clearance, query the yaw rate corresponding to the current clearance from a relationship database, wherein the relationship database contains a mapping relationship between the clearance value and the yaw rate; or, according to the clearance value of the current clearance, calculate the yaw rate corresponding to the current clearance in real time through the mapping relationship between the clearance value and the yaw rate.

[0095] According to an embodiment of the present disclosure, a computer readable storage medium storing instructions is provided, wherein the instructions, when executed by at least one computing device, cause the at least one computing device to perform the wind turbine generator set clearance control method according to any one of the above embodiments.

[0096] According to an embodiment of the present disclosure, a system including at least one computing device and at least one storage device storing instructions is provided, wherein the instructions, when executed by the at least one computing device, cause the at least one computing device to perform the wind turbine generator set clearance control method according to any one of the above embodiments.

[0097] Although some embodiments of the present disclosure have been shown and described, it should be understood by those skilled in the art that modifications can be made to these embodiments without departing from the principles and spirit of the present disclosure, which are defined by the following claims and their equivalents.

Claims

1. A method of clearance control for a wind turbine, characterized in that, The method comprises: determining a yaw direction of the wind turbine according to the yaw direction of the rotor of the wind turbine, and determining a yaw rate according to the clearance information of the wind turbine; controlling the wind turbine to yaw the rotor up in the yaw direction and at the yaw rate to improve the clearance of the wind turbine; wherein the determining the yaw direction according to the yaw direction of the rotor of the wind turbine comprises: in the case that the wind turbine is an upwind wind turbine, when the yaw direction of the rotor is clockwise, determining the yaw direction as right turning of the wind turbine; and when the yaw direction of the rotor is counterclockwise, determining the yaw direction as left turning of the wind turbine; in the case that the wind turbine is a downwind wind turbine, when the yaw direction of the rotor is clockwise, determining the yaw direction as left turning of the wind turbine; and when the yaw direction of the rotor is counterclockwise, determining the yaw direction as right turning of the wind turbine, wherein the yaw direction of the rotor is determined according to the upwind view. after the controlling the wind turbine to yaw the rotor up in the yaw direction and at the yaw rate, the method further comprises:

2. The headroom control method of claim 1, wherein, detecting a first clearance of the wind turbine after yawing; in response to the first clearance being greater than or equal to the safety clearance threshold, maintaining the current yaw state of the wind turbine; in response to the first clearance still being less than the safety clearance threshold, increasing the yaw rate. after the controlling the wind turbine to yaw the rotor up in the yaw direction and at the yaw rate, the method further comprises:

3. The headroom control method of claim 1, wherein, detecting a second clearance of the wind turbine after yawing; in response to the second clearance being greater than a predetermined clearance threshold, controlling the wind turbine to return to a normal operating state, wherein the predetermined clearance threshold is greater than the safety clearance threshold. the controlling the wind turbine to yaw the rotor up in the yaw direction and at the yaw rate comprises:

4. The headroom control method of claim 1, wherein, determining a predetermined yaw angle according to the clearance value of the current clearance and the average wind speed; controlling the wind turbine to yaw the rotor up in the yaw direction and at the yaw rate, and yawing to the predetermined yaw angle, so that the clearance of the wind turbine is greater than or equal to the safety clearance threshold. the determining the yaw rate according to the clearance information of the wind turbine comprises:

5. The headroom control method of claim 1, wherein, determining the yaw rate according to the clearance value of the current clearance; or determining the yaw rate according to the clearance reduction rate within a predetermined time period before the current time. the determining the yaw rate according to the clearance value of the current clearance comprises:

6. The headroom control method of claim 5, wherein, querying the yaw rate corresponding to the current clearance from a relationship database according to the clearance value of the current clearance, wherein the relationship database contains the mapping relationship between the clearance value and the yaw rate; or calculating the yaw rate corresponding to the current clearance in real time through the mapping relationship between the clearance value and the yaw rate according to the clearance value of the current clearance. the current clearance of the wind turbine is determined to be less than the safety clearance threshold in one of the following ways: ​ 7. The headroom control method of claim 1, wherein, ​ the wind turbine exceeds a safe deformation threshold; the wind turbine exceeds a safe load threshold; the current clearance has a clearance value that is less than the safe clearance threshold.

8. A computer-readable storage medium storing instructions, wherein, The instructions, when executed by at least one computing device, cause the at least one computing device to perform the wind turbine clearance control method of any one of claims 1-7.

9. A wind power unit, characterized in that The wind turbine comprises: a rotor; a yaw mechanism configured to cause the wind turbine to perform a yaw action; a memory configured to store instructions; a controller configured to execute the stored instructions stored in the memory, causing the yaw mechanism to perform the wind turbine clearance control method of any one of claims 1-7.

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