Method and device for identifying blade stall of wind turbine generator set

Abstract

The present disclosure provides a method and apparatus for identifying blade stall in a wind turbine generator set. The blade stall identification method may include identifying an output power anomaly of the wind turbine generator set; controlling the wind turbine generator set to perform pitch control in response to identifying the output power anomaly of the wind turbine generator set; obtaining operating parameters of the wind turbine generator set within a predetermined time period after the start of the pitch control; and identifying whether the cause of the output power anomaly includes blade stall based on changes in the operating parameters within the predetermined time period.

Description

Technical Field

[0001] The present disclosure relates to the field of wind power generation, and in particular to a method and device for identifying blade stall of a wind turbine generator set. Background Art

[0002] During wind turbine operation, blades can experience adverse operating conditions such as icing and contamination due to factors such as severe weather, which can cause blade stall. Blade stall rapidly increases blade fatigue accumulation and, in severe cases, can easily lead to blade breakage within a short period of time.

[0003] Blade stall can have many adverse effects on the operation of wind turbines. For example, the relationship between wind speed and the output power of the wind turbine becomes abnormal. For example, the output power is too small relative to the wind speed, which is the "high wind and low power" problem.

[0004] However, blade stall is only one of many causes of wind turbine failure. Other factors can also contribute to failure, such as inaccurate yaw alignment, structural vibration within the turbine system, abnormal electrical system losses, and measurement system deviations. Therefore, when a wind turbine malfunction is discovered, it can be difficult to determine the true cause and determine in real time whether blade stall is the cause. Summary of the Invention

[0005] The purpose of the embodiments of the present disclosure is to provide a blade stall identification method and a blade stall identification device for a wind turbine generator set, so as to accurately identify blade stall and help ensure the safe operation of the wind turbine generator set.

[0006] According to an embodiment of the present disclosure, a method for identifying blade stall of a wind turbine is provided, the method comprising: identifying an output power anomaly of the wind turbine; controlling the wind turbine to perform pitch change in response to identifying the output power anomaly of the wind turbine; obtaining operating parameters of the wind turbine within a predetermined time period after starting the pitch change; and identifying whether the cause of the output power anomaly includes blade stall based on changes in the operating parameters within the predetermined time period.

[0007] According to an embodiment of the present disclosure, a blade stall identification device for a wind turbine is provided, the blade stall identification device comprising: an output power abnormality identification unit configured to identify an output power abnormality of the wind turbine; a pitch control unit configured to control the wind turbine to perform pitch change in response to identifying an output power abnormality of the wind turbine; the blade stall identification unit configured to obtain operating parameters of the wind turbine within a predetermined time period after starting the pitch change; and identify whether the cause of the output power abnormality includes blade stall based on changes in the operating parameters within the predetermined time period.

[0008] According to an embodiment of the present disclosure, a computer-readable storage medium storing a computer program is provided. When the computer program is executed by a processor, the blade stall method as described above is implemented.

[0009] According to an embodiment of the present disclosure, a computing device is provided, comprising: a processor; and a memory storing a computer program. When the computer program is executed by the processor, the blade stall method described above is implemented.

[0010] The blade stall identification method and blade stall identification device of a wind turbine generator set according to the embodiments of the present disclosure can achieve one of the following technical effects: it can simply and effectively determine in real time online whether the cause of the abnormal output power of the wind turbine generator set includes blade stall, and can timely and effectively avoid the hazards caused by blade stall, and solve the safety hazards existing in the operation of the wind turbine generator set; based on the judgment results, the operation of the wind turbine generator set can be intervened in time, and then the risks of blade breakage caused by blade stall can be eliminated in time and effectively, thereby ensuring the safe operation of the wind turbine generator set.

[0011] Other aspects and / or advantages of the general inventive concept of the present disclosure will be set forth in part in the following description and will in part be apparent from the description or may be learned through practice of the general inventive concept of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The above and other objects and features of the present disclosure will become more apparent from the following description in conjunction with the accompanying drawings.

[0013] Figure 1 4 is a flow chart of a method for identifying blade stall of a wind turbine generator set according to an embodiment of the present disclosure.

[0014] Figure 2 Schematic diagram of a speed triangle of a wind turbine generator set according to an embodiment of the present disclosure.

[0015] Figure 3 4 is a graph showing the relationship between blade lift and blade angle of attack of a wind turbine generator set according to an embodiment of the present disclosure.

[0016] Figure 4 4 is a graph showing the relationship between blade resistance and blade angle of attack of a wind turbine generator set according to an embodiment of the present disclosure.

[0017] Figures 5 to 8 is a partial flow chart of a method for identifying blade stall of a wind turbine generator system according to an exemplary embodiment of the present disclosure.

[0018] Figure 9 4 is a schematic block diagram of a blade stall identification device for a wind turbine generator set according to an embodiment of the present disclosure.

[0019] Figure 10 is a schematic diagram of a computing device according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0020] The following detailed description is provided to help the reader gain a comprehensive understanding of the methods, devices and / or systems described herein. However, various changes, modifications and equivalents of the methods, devices and / or systems described herein will be clear after understanding the disclosure of the present application. For example, the order of operations described herein is merely 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 conciseness, descriptions of features known in the art may be omitted.

[0021] The features described herein can be implemented in different forms and should not be construed as limited to the examples described herein. Rather, the examples described herein are provided to illustrate only some of the many possible ways to implement the methods, devices, and / or systems described herein, which will become clear after understanding the disclosure of this application.

[0022] As used herein, the term "and / or" includes any one of the associated listed items and any combination of any two or more.

[0023] 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 used solely to distinguish one member, component, region, layer, or portion from another member, component, region, layer, or portion. Thus, what is referred to as a first member, first component, first region, first layer, or first portion in the examples described herein may also be referred to as a second member, second component, second region, second layer, or second portion without departing from the teachings of the examples.

[0024] 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 is intended to include the plural. The terms "comprise," "include," and "have" indicate the presence of the recited features, quantities, operations, components, elements, and / or combinations thereof, but do not preclude the presence or addition of one or more other features, quantities, operations, components, elements, and / or combinations thereof.

[0025] Unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which the present disclosure pertains after understanding the present disclosure. Unless expressly defined otherwise herein, terms (such as those defined in general dictionaries) 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.

[0026] Furthermore, in describing the examples, when it is deemed that a detailed description of well-known related structures or functions would cause an obscure interpretation of the present disclosure, such detailed description will be omitted.

[0027] During the operation of a wind turbine, when the wind turbine output power is abnormal (for example, the output power is too small relative to the wind speed, that is, the "strong wind and low power" problem occurs), it is necessary to determine the cause of the abnormal output power in real time. The causes are various, such as blade stall, inaccurate yaw to wind, structural vibration in the unit system, abnormal electrical system loss, deviation in the measurement system, etc.

[0028] Blade stall is one of the more serious causes of failure. Blade stall refers to the following phenomenon: when the wind turbine is in normal operating conditions, the blade angle of attack is very small, and the airflow bypasses the airfoil blades and remains streamlined. When the airflow forms a positive angle of attack with the blade inlet, that is, the blade angle of attack is greater than 0, and this positive angle of attack exceeds a certain critical value, the gas flow conditions on the back of the blade begin to deteriorate, the boundary layer is destroyed, and a vortex zone appears at the rear end of the blade. The change in the blade airfoil during blade stall often causes flow separation on the blade suction surface, resulting in an increase in the blade angle of attack, a decrease in blade lift, and an increase in blade drag. This can cause a rapid increase in the cumulative fatigue load on the blade, and in severe cases, can easily induce blade fracture within a short period of time.

[0029] Therefore, identifying blade stall is particularly important. By determining in real time whether an abnormal output power is caused by blade stall, the hazards caused by blade stall can be promptly and effectively avoided, resolving potential safety hazards during wind turbine operation. When a wind turbine malfunction is discovered, if it is difficult to determine the true cause of the malfunction and to determine in real time whether the malfunction is caused by blade stall, the hazards caused by blade stall cannot be promptly and effectively avoided, making it difficult for the wind turbine to overcome potential safety hazards.

[0030] Blade stall is usually identified by identifying fault characteristics caused by blade stall reaching a certain severity. However, the accuracy and timeliness of such identification methods are limited. In order to identify blade stall more effectively and in real time, the present disclosure proposes a technical solution for blade stall identification of wind turbines based on a deep understanding of blade aerodynamics and overall machine control. It can simply and effectively determine in real time online whether the cause of abnormal output power of the wind turbine includes blade stall; based on the judgment result, timely intervention can be made in the operation of the wind turbine, and then the risks of blade breakage caused by blade stall can be eliminated in a timely and effective manner to ensure the safe operation of the wind turbine. The technical solution for blade stall identification proposed in the present disclosure can identify blade stall more directly and effectively based on the essence of blade stall.

[0031] The following will describe a method and device for identifying blade stall of a wind turbine generator set according to an embodiment of the present disclosure with reference to the accompanying drawings. However, the embodiments of the present disclosure are not limited to the following description.

[0032] According to an embodiment of the present disclosure, a blade stall identification method may include: identifying an output power anomaly of a wind turbine; controlling the wind turbine to perform pitch control in response to identifying the output power anomaly of the wind turbine; obtaining operating parameters of the wind turbine within a predetermined time period after the start of the pitch control; and identifying whether the cause of the output power anomaly includes blade stall based on changes in the operating parameters within the predetermined time period. The blade stall identification method may be performed by a device capable of controlling the wind turbine, such as a controller of the wind turbine and / or an external controller connected to the wind turbine.

[0033] Optionally, the inflow angle of the blades of the wind turbine generator set remains unchanged during the predetermined time period. Furthermore, the pitch angle of the blades of the wind turbine generator set may be increased by a predetermined amount, such that the increased pitch angle remains unchanged until the predetermined time period expires. Optionally, after the predetermined time period expires, the pitch angle may be restored to its pre-increase state. Optionally, the pitch angle may be reduced to a minimum pitch angle.

[0034] Figure 1 4 is a flow chart of a method for identifying blade stall of a wind turbine generator set according to an embodiment of the present disclosure.

[0035] like Figure 1 As shown, in step S11, an output power anomaly of the wind turbine is identified. According to an embodiment of the present disclosure, the output power anomaly may include that the actual output power of the wind turbine is too low relative to the actual wind speed. The output power anomaly can be identified in a variety of ways. For example, the actual output power of the wind turbine and the wind speed at the site where the wind turbine is located can be obtained, and the actual output power can be compared with the maximum output power at the corresponding wind speed to determine whether the actual output power is abnormal. The maximum output power can be the ideal output power or theoretical output power of the wind turbine. For example, the maximum output power at different wind speeds can be determined based on a curve of the change of the theoretical output power of the wind turbine relative to the wind speed.

[0036] By continuously or periodically executing step S11, it is possible to identify in real time whether the wind turbine's output power is abnormal. In step S12, it is determined whether an abnormality has been identified in the wind turbine's output power. If so, step S13 is executed; otherwise, step S11 is continued. For example, if the wind turbine's actual output power is significantly lower than the maximum output power at the corresponding wind speed, an abnormality in the wind turbine's output power is determined to have been identified.

[0037] In step S13, the wind turbine generator set may be controlled to perform pitch change. For example, the pitch change operation may be controlled by the pitch controller of the wind turbine generator set. For example, the pitch angle of the wind turbine generator set may be actively changed by actively performing pitch change, thereby causing a change in the blade angle of attack. However, the present disclosure is not limited thereto, and other pitch change operations may also be used to actively cause a change in the blade angle of attack, so as to facilitate identification of blade stall. Since the change in angle of attack in a blade stall state and a non-blade stall state has different effects on the operation of the wind turbine generator set, it is possible to identify whether the cause of the output power abnormality includes blade stall based on the change in operating parameters after the active start of pitch change.

[0038] According to an embodiment of the present disclosure, in step S14, the operating parameters of the wind turbine generator set within a predetermined time period after the start of pitch change are obtained. For example, the operating parameters may include but are not limited to at least one of the following items: the blade speed, output power, power generation, and wind energy absorption of the wind turbine generator set. After the wind turbine generator set starts to change pitch, due to the lag in the change of the inflow angle of the blade, the inflow angle remains unchanged in a short period of time, however, the angle of attack of the blade will change with the change of the pitch angle. The following will be combined with Figure 2 Analyze its principles.

[0039] Figure 2 Schematic diagram of a speed triangle of a wind turbine generator set according to an embodiment of the present disclosure.

[0040] like Figure 2 As shown in Figure 1, the wind speed V at the wind turbine generator station, the blade's linear velocity U (e.g., the linear velocity or tangential velocity at the blade tip), and the blade's inflow angle I form a velocity triangle. Based on the wind speed V and linear velocity U, the blade's inflow angle can be determined using the following formula.

[0041] I=arctan(V / U) (1)

[0042] The inflow angle of a blade is directly related to the blade's pitch angle, blade angle of attack, and blade twist angle. The pitch angle and angle of attack are particularly closely related. For example, the inflow angle is equal to the sum of the pitch angle and the angle of attack. Therefore, when the inflow angle remains constant, the blade's angle of attack will change with changes in the pitch angle. For example, the angle of attack decreases as the pitch angle increases.

[0043] Changes in the blade angle of attack will cause changes in the operating parameters of the wind turbine generator set. Therefore, the changes in the blade angle of attack can be obtained based on the changes in the operating parameters. The blade angle of attack is directly related to blade stall (for example, blade stall is directly reflected as the angle of attack becoming too large). Therefore, whether blade stall has occurred can be identified based on the changes in the operating parameters.

[0044] Refer again Figure 1 In step S15, the cause of the abnormal output power may be identified based on the change of the operating parameters within a predetermined time period to determine whether the cause includes blade stall. Figure 3 and Figure 4 Described examples to execute.

[0045] Figure 3 4 is a graph showing the relationship between blade lift and blade angle of attack of a wind turbine generator set according to an embodiment of the present disclosure. Figure 4 4 is a graph showing the relationship between blade resistance and blade angle of attack of a wind turbine generator set according to an embodiment of the present disclosure.

[0046] like Figure 3 As shown in , the horizontal axis represents the blade's angle of attack, and the vertical axis represents the blade's lift. Figure 4 As shown in the figure, the horizontal axis represents the blade's angle of attack, and the vertical axis represents the blade's resistance. Figure 3 and Figure 4 , when the angle of attack is in the normal operating range (e.g., zero to a predetermined stall angle of attack (e.g., Figure 3 When the angle of attack varies within the blade's velocity range (approximately 12° in the example, referred to as the attached flow region), the blade's lift increases with increasing angle of attack, while the blade's drag remains nearly constant, indicating stable operation. When the angle of attack varies within the stall region—that is, when the angle of attack is greater than the predetermined stall angle—the blade's lift decreases sharply with increasing angle of attack, while the blade's drag also increases sharply, indicating blade stall.

[0047] The present invention takes into account that when the angle of attack is equal to or greater than the predetermined stall angle of attack, the blades have stalled, resulting in abnormal output power during the operation of the wind turbine. At this time, the pitch angle can be temporarily and quickly increased by a predetermined amplitude through active pitch control, and the inflow angle lags behind the pitch action. Therefore, when the pitch angle begins to increase by a predetermined amplitude and / or within a short time (for example, 3 seconds) after the predetermined amplitude is increased, the angle of attack will decrease as the pitch angle increases. When the angle of attack decreases to less than the predetermined stall angle of attack, the blades are out of the stall state, causing the operating parameters of the wind turbine to change in a relatively short period of time, for example, the lift of the blades increases, the resistance of the blades decreases, the blade speed increases, the output power of the wind turbine increases, the generated power increases, the wind energy absorption (for example, the wind energy absorption of the impeller) increases, and so on.

[0048] The present invention also contemplates that, when the blades are not stalled, the pitch angle can be temporarily and rapidly increased by a predetermined amount through active pitch control. During the initial increase in the pitch angle by the predetermined amount and / or in the short period following the increase by the predetermined amount, changes in the wind turbine's operating parameters can differ significantly from those described above in the case of blade stall. For example, this can result in a decrease in the blade's aerodynamic torque, a decrease in the blade's lift, almost constant blade drag, a decrease in the blade's rotational speed, a decrease in the wind turbine's output power, a decrease in generated power, and a decrease in wind energy absorption (e.g., the amount absorbed by the impeller).

[0049] Therefore, under the two different operating conditions of blade stall and non-blade stall, the changes in operating parameters caused by temporarily increasing the pitch angle are opposite, which provides a theoretical basis for effectively identifying whether the cause of output power abnormality includes blade stall.

[0050] According to an exemplary embodiment of the present disclosure, the inflow angle of the blades of the wind turbine generator set remains unchanged for a predetermined time period after the start of the pitch change. For example, the predetermined time period can be set based on the time period (e.g., the lag period) during which the inflow angle remains unchanged after the start of the pitch change. For example, but not limited to, the predetermined time period can be very short, such as 3 seconds, 5 seconds, etc. In addition, the pitch angle of the blades of the wind turbine generator set can be increased by a predetermined amount, so that the increased pitch angle remains unchanged until the end of the predetermined time period.

[0051] The following combination Figures 5 to 7 A blade stall identification method for a wind turbine according to an exemplary embodiment of the present disclosure is further described. Figures 5 to 7 is a partial flow chart of a method for identifying blade stall of a wind turbine generator system according to an exemplary embodiment of the present disclosure.

[0052] According to an exemplary embodiment of the present disclosure, an abnormality in the output power of a wind turbine generator set may be identified based on a ratio between the actual output power of the wind turbine generator set and the maximum output power at a corresponding wind speed. For example, an abnormality in the output power of a wind turbine generator set may be identified in response to the ratio between the actual output power of the wind turbine generator set and the maximum output power at a corresponding wind speed being less than or equal to a predetermined ratio.

[0053] According to an exemplary embodiment of the present disclosure, the relationship between the output power and wind speed of a wind turbine generator set can be obtained in real time. Figure 5 As shown, in step S51, the ratio between the actual output power of the wind turbine generator set and the maximum output power at the corresponding wind speed can be obtained. For example, the actual output power of the wind turbine generator set can be obtained by a power measuring device or a power calculating device, and the maximum output power at the corresponding wind speed of the actual output power can be obtained based on a curve of the change of the theoretical output power of the wind turbine generator set relative to the wind speed (for example, based on the current wind speed value, the theoretical output power value Pi is searched, where i is the wind speed bin in which the current wind speed is located). Then, the ratio between the actual output power and the maximum output power at the corresponding wind speed is calculated.

[0054] In case of abnormal output power, a predetermined ratio may be set to compare with the ratio obtained above to determine whether the output power is abnormal.

[0055] In step S52, it is determined whether the ratio is less than or equal to a predetermined ratio. If so, step S53 is executed, otherwise step S51 is continued to be executed, thereby continuously identifying output power anomalies.

[0056] For example, when the wind speed is above 20 m / s, the actual output power of the wind turbine generator set is far lower than the full power (i.e., maximum output power) of the wind turbine generator set. For example, the ratio of the actual output power to the maximum output power is 0.2, while the predetermined ratio is set to 1. Because the obtained ratio is less than the predetermined ratio, an abnormal output power of the wind turbine generator set is identified. The predetermined ratio can be any value greater than 0 and less than or equal to 1.

[0057] Optionally, the predetermined ratio may include multiple predetermined ratios, each corresponding to a plurality of predetermined severity levels. Thus, by setting multiple different predetermined ratios, the severity of the output power anomaly can be determined in real time.

[0058] According to an embodiment of the present disclosure, the severity level of the identified output power anomaly is determined by comparing the ratio between the actual output power of the wind turbine generator set and the maximum output power at the corresponding wind speed with the plurality of predetermined ratios.

[0059] For example, the first severity level corresponds to a first predetermined ratio, the second severity level corresponds to a second predetermined ratio, and the third severity level corresponds to a third predetermined ratio. In terms of severity, the first severity level is higher than the second severity level, which is higher than the third severity level. Accordingly, the first predetermined ratio (e.g., 0.65) is smaller than the second predetermined ratio (e.g., 0.75), and the second predetermined ratio is smaller than the third predetermined ratio (e.g., 1.0).

[0060] When the ratio between the actual output power of the wind turbine generator set and the maximum output power at the corresponding wind speed is less than or equal to the first predetermined ratio, the output power abnormality is identified as being at the first severity level; when the ratio between the actual output power of the wind turbine generator set and the maximum output power at the corresponding wind speed is less than or equal to the second predetermined ratio and greater than the first predetermined ratio, the output power abnormality is identified as being at the second severity level; when the ratio between the actual output power of the wind turbine generator set and the maximum output power at the corresponding wind speed is less than or equal to the third predetermined ratio and greater than the second predetermined ratio, the output power abnormality is identified as being at the third severity level.

[0061] In addition, the severity level of the output power anomaly can be used to measure the severity of the output power anomaly and can also be used to set the increase range of the pitch angle during active pitch control.

[0062] The following combination Figure 6 The blade stall identification method is further described. Figure 6 As shown, in step S61, the pitch angle of the blades of the wind turbine generator set may be increased by a predetermined amount, so that the increased pitch angle remains unchanged until the end of a predetermined period after the start of pitch change. Optionally, according to an embodiment of the present disclosure, the pitch angle increase speed may be set to a relatively high speed (e.g., 3° / s) to quickly increase the pitch angle.

[0063] According to an embodiment of the present disclosure, a predetermined amplitude can be set according to the severity level of the output power anomaly. For example, multiple predetermined amplitudes corresponding to multiple severity levels can be set. For example, a first predetermined amplitude can be set according to the first severity level, a second predetermined amplitude can be set according to the second severity level, and a third predetermined amplitude can be set according to the third severity level. Since the severity of the first severity level, the second severity level, and the third severity level decreases in sequence, the first predetermined amplitude (for example, 5°) is greater than the second predetermined amplitude (for example, 4°), and the second predetermined amplitude is greater than the third predetermined amplitude (for example, 3°).

[0064] Optionally, the predetermined amplitude can be set by obtaining the blade angle of attack. For example, the blade angle of attack at the time the output power abnormality is identified can be obtained; the predetermined amplitude can be set based on the obtained blade angle of attack and the predetermined stall angle of attack. This allows the predetermined amplitude to be adjusted in real time, facilitating timely identification of blade stall.

[0065] According to the embodiment of the present disclosure, the blade angle of attack can be obtained in real time according to the aerodynamic mechanism of the blade. Figure 2 The blade angle of attack is obtained in real time using the aerodynamic mechanism described by equation (1). The blade inflow angle can be calculated based on the linear velocity of the blade and the wind speed at the wind turbine generator station (for example, according to equation (1)). The blade angle of attack can then be calculated based on the difference between the inflow angle and the pitch angle.

[0066] According to an embodiment of the present disclosure, the predetermined amplitude can be set by comparing the relative magnitude of the acquired blade angle of attack with the predetermined stall angle of attack. For example, the statistical value of the difference between the acquired blade angle of attack and the predetermined stall angle of attack (e.g., the absolute value or variance of the difference) can be set as the predetermined amplitude.

[0067] Optionally, a predetermined amplitude is set based on the obtained blade angle of attack, a predetermined stall angle of attack, and a predetermined adjustment value. For example, a predetermined amplitude can be set based on a statistical value of the difference between the obtained blade angle of attack and the predetermined stall angle of attack (for example, the absolute value of the difference, the variance, etc.) and a predetermined adjustment value. For example, the sum of a statistical value of the difference between the obtained blade angle of attack and the predetermined stall angle of attack (for example, the absolute value of the difference, the variance, etc.) and a predetermined adjustment value can be set as a predetermined amplitude. However, the present disclosure is not limited thereto, and a predetermined amplitude can also be set based on other statistical values of the obtained blade angle of attack, the predetermined stall angle of attack, and the predetermined adjustment value. By additionally setting the predetermined amplitude based on the predetermined adjustment value, the blade can be made to escape from a stall state more easily.

[0068] According to an embodiment of the present disclosure, a predetermined adjustment value can be set based on the severity level of the output power anomaly. This setting method is similar to the above-mentioned setting method for the predetermined amplitude. In this way, the predetermined amplitude of the increase can be further adjusted in real time based on the severity level. Based on the real-time acquired blade angle of attack and the real-time determined severity level of the output power anomaly, the predetermined adjustment value used to set the predetermined amplitude can be adjusted in real time, thereby accurately and effectively allowing the blade to quickly escape the stall state and maintain the non-stall state until the end of the above-mentioned predetermined time period.

[0069] According to an embodiment of the present disclosure, it is possible to identify whether the change in the operating parameter within a predetermined time period includes an increase; in response to the change in the operating parameter within the predetermined time period including an increase, it is determined that the cause of the output power abnormality includes blade stall.

[0070] After starting to execute pitch change to increase the pitch angle by a predetermined amplitude, step S62 may be executed to identify whether the change of the operating parameter within the predetermined time period includes an increase. If yes, step S63 is executed, otherwise step S62 is continued to be executed.

[0071] Refer to the following Figure 7Further describing how to identify whether a change in an operating parameter within a predetermined time period includes an increase. According to an embodiment of the present disclosure, a maximum change value of the operating parameter within the predetermined time period may be obtained; and in response to the maximum change value being greater than or equal to a predetermined change threshold, determining that the change in the operating parameter within the predetermined time period includes an increase.

[0072] Here, monitoring the changes in blade speed is used as an example to illustrate, but the present disclosure is not limited to this. It is also possible to identify whether the cause of the output power abnormality includes blade stall by monitoring the changes in one or more operating parameters such as blade speed, output power, power generation power, wind energy absorption, etc. within a predetermined time period after the start of pitch change.

[0073] like Figure 7 As shown, in step S71, the maximum change value of the operating parameter within a predetermined time period can be obtained. For example, the change in the blade speed can be monitored within a predetermined time period after the start of pitch control (for example, in the stage of executing the active pitch control action), for example, the maximum change value within the predetermined time period is calculated based on the statistical value of the change in the blade speed within the predetermined time period. For example, the sliding average value of the blade speed in the first time period within the predetermined time period can be obtained. The length of the first time period can be less than the predetermined time period. The difference between the blade speed in the predetermined time period and the above-mentioned sliding average value (that is, the blade speed minus the above-mentioned sliding average value) can be calculated, and then the maximum value of the difference is taken as the maximum change value of the blade speed within the predetermined time period. When the maximum change value is greater than the predetermined change threshold, it can be determined that the change in the operating parameter within the predetermined time period includes an increase (step S73). According to an embodiment of the present disclosure, in response to determining that the change in the operating parameter within the predetermined time period includes an increase, it is determined that the cause of the output power abnormality includes blade stall.

[0074] According to an embodiment of the present disclosure, after identifying whether the cause of the output power abnormality includes blade stall, a corresponding warning may be output and / or a corresponding protection operation may be performed.

[0075] According to an embodiment of the present disclosure, in response to identifying that the cause of the output power abnormality includes blade stall, a blade stall warning is output, and / or a protection operation corresponding to blade stall is performed. Optionally, in response to identifying that the cause of the output power abnormality does not include blade stall, a non-blade stall warning is output, and / or a protection operation corresponding to non-blade stall is performed. Figure 8 A schematic description is given.

[0076] In step S81, it can be determined whether the cause of the output power abnormality includes blade stall. If so, step S82 (output blade stall warning) and / or step S83 (execute protection operation corresponding to blade stall) are executed; otherwise, step S84 (output non-blade stall warning) and / or step S85 (execute protection operation corresponding to non-blade stall) are executed.

[0077] According to an embodiment of the present disclosure, each blade stall warning may include warning information corresponding to the severity level of the identified output power anomaly. Alternatively, a non-blade stall warning may include warning information corresponding to the severity level of the identified output power anomaly. The protection operation corresponding to blade stall may include a protection operation corresponding to the severity level of the identified output power anomaly. Alternatively, the protection operation corresponding to non-blade stall may include a protection operation corresponding to the severity level of the identified output power anomaly.

[0078] According to embodiments of the present disclosure, protective actions corresponding to blade stall may include, but are not limited to, at least one of the following: reducing the output power of the wind turbine generator set, adjusting the pitch angle, and shutting down for protection. For example, but not limited to, protective actions corresponding to blade stall may include shutting down for protection corresponding to the first severity level of the output power anomaly, and adjusting the pitch angle for protection corresponding to the second severity level of the output power anomaly. For example, when the output power anomaly is at the first severity level and the cause of the output power anomaly is determined to include blade stall, shutting down for protection may be performed to prevent blade stall. When the output power anomaly is at the second severity level and the cause of the output power anomaly is determined to include blade stall, adjusting the pitch angle may be performed to prevent blade stall, thereby promptly avoiding safety risks caused by blade stall. Protective actions corresponding to non-blade stall conditions may include, but are not limited to, at least one of the following: reducing the output power of the wind turbine generator set, shutting down for protection, and the like. For example, but not limited to, protective actions corresponding to non-blade stall conditions may include shutting down for protection corresponding to the first severity level of the output power anomaly, and reducing output power corresponding to the second severity level of the output power anomaly. For example, when the output power abnormality is at the first severity level and it is determined that the cause of the output power abnormality does not include blade stall, shutdown protection can be performed to avoid output power abnormality caused by non-blade stall; when the output power abnormality is at the second severity level and it is determined that the cause of the output power abnormality does not include blade stall, the pitch angle can be adjusted to avoid output power abnormality caused by non-blade stall, thereby timely avoiding safety risks caused by non-blade stall.

[0079] As described above, in response to identifying that the cause of the output power abnormality includes blade stall, the safety risk caused by the blade stall can be promptly eliminated by outputting a blade stall warning and / or performing corresponding protection operations.

[0080] Reference above Figures 1 to 8 The present invention describes a method for identifying blade stall of a wind turbine generator set according to an embodiment of the present invention. Figure 9 A blade stall identification device for a wind turbine generator system according to an embodiment of the present disclosure is described.

[0081] Figure 9 Figure 2 is a schematic block diagram of a blade stall identification device 2 for a wind turbine generator set according to an embodiment of the present disclosure. Blade stall identification device 2 may include an output power anomaly identification unit 21, a pitch control unit 22, and a blade stall identification unit 23. Blade stall identification device 2 and its various units or components may be implemented by a wind turbine generator set controller and / or a controller connected to the wind turbine generator set, or other device capable of controlling the wind turbine generator set.

[0082] The output power anomaly identification unit 21 can identify an output power anomaly of a wind turbine generator set. For example, the output power anomaly identification unit 21 can obtain the actual output power of the wind turbine generator set and the wind speed at the generator site where the wind turbine generator set is located, compare the actual output power with the maximum output power at the corresponding wind speed, and then determine whether the actual output power is abnormal.

[0083] In response to identifying an abnormal output power of the wind turbine generator set, the pitch control unit 22 can control the wind turbine generator set to perform pitch control. For example, the pitch control unit 22 can actively change the pitch angle of the wind turbine generator set by actively performing pitch control, thereby causing a change in the blade angle of attack. However, the present disclosure is not limited to this, and other pitch control operations can also be used to actively cause a change in the blade angle of attack to facilitate the identification of blade stall.

[0084] The blade stall identification unit 23 may obtain operating parameters of the wind turbine generator set within a predetermined time period after the start of the pitch change operation; and identify whether the cause of the abnormal output power includes blade stall based on changes in the operating parameters within the predetermined time period. For example, the blade stall identification unit 23 may identify whether the changes in the operating parameters within the predetermined time period after the start of the pitch change operation include an increase; and in response to the changes in the operating parameters within the predetermined time period including an increase, determine that the cause of the abnormal output power includes blade stall.

[0085] Optionally, the blade stall identification device 2 may further include a protection execution unit 24. In response to identifying that the cause of the output power abnormality includes blade stall, the protection execution unit 24 may output a blade stall warning and / or execute a protection operation corresponding to blade stall. In response to identifying that the cause of the output power abnormality does not include blade stall, the protection execution unit 24 may output a non-blade stall warning and / or execute a protection operation corresponding to a non-blade stall. Optionally, the protection execution unit 24 may also communicate with the power abnormality identification unit 21 to execute a protection operation and / or output an abnormality warning in response to the power abnormality identification unit 21 identifying an output power abnormality.

[0086] Please refer to Figures 1 to 8 The corresponding operations of the various units of the blade stall identification device 2 can be understood by referring to the various steps in the blade stall identification method for a wind turbine generator set described above, which will not be described in detail here for the sake of simplicity.

[0087] According to an embodiment of the present disclosure, there is further provided a computer-readable storage medium having a computer program stored thereon. When the computer program is executed, the data processing method according to the embodiment of the present disclosure is implemented.

[0088] In the embodiment of the present disclosure, the computer readable storage medium may carry one or more programs, and when the computer program is executed, reference may be made to Figures 1 to 8 The following steps are described: identifying an output power anomaly of a wind turbine generator set; controlling the wind turbine generator set to perform pitch change in response to identifying the output power anomaly of the wind turbine generator set; obtaining operating parameters of the wind turbine generator set within a predetermined time period after starting the pitch change; and identifying whether the cause of the output power anomaly includes blade stall based on changes in the operating parameters within the predetermined time period.

[0089] Computer-readable storage media can be, for example, but not limited to, electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems, devices or components, or any combination thereof. More specific examples of computer-readable storage media can include, but are not limited to: an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination thereof. In embodiments of the present disclosure, a computer-readable storage medium can be any tangible medium that contains or stores a computer program that can be used by or in conjunction with an instruction execution system, device or component. The computer program contained on the computer-readable storage medium can be transmitted using any suitable medium, including but not limited to: wires, optical cables, RF (radio frequency), etc., or any suitable combination thereof. The computer-readable storage medium can be contained in any device; it can also exist independently without being assembled into the device.

[0090] The above has been combined Figures 1 to 8 The blade stall identification method according to the embodiment of the present disclosure is described. Figure 10 A computing device according to an embodiment of the present disclosure is described.

[0091] Figure 10 is a schematic diagram of a computing device according to an embodiment of the present disclosure.

[0092] Reference Figure 10 According to an embodiment of the present disclosure, the computing device 3 may include a memory 31 and a processor 32 . A computer program 33 is stored in the memory 31 . When the computer program 33 is executed by the processor 32 , the blade stall identification method according to an embodiment of the present disclosure is implemented.

[0093] In the embodiment of the present disclosure, when the computer program 33 is executed by the processor 32, reference to Figures 1 to 8 The operation of the blade stall identification method described is as follows: identifying an output power abnormality of a wind turbine generator set; in response to identifying the output power abnormality of the wind turbine generator set, controlling the wind turbine generator set to perform pitch change; obtaining operating parameters of the wind turbine generator set within a predetermined time period after starting the pitch change; and identifying whether the cause of the output power abnormality includes blade stall based on changes in the operating parameters within the predetermined time period.

[0094] Figure 10 The computing device shown is only an example and should not bring any limitation to the functions and usage scope of the embodiments of the present disclosure.

[0095] The above has been referred to Figures 1 to 10 The blade stall identification method, device, and computing device of a wind turbine generator set according to the embodiments of the present disclosure are described. However, it should be understood that: Figure 9 The blade stall identification device and its respective units shown in the figure may be configured as software, hardware, firmware or any combination thereof to perform specific functions. Figure 10 The computing device shown in the figure is not limited to include the units or components shown above, but some units or components may be added or deleted as needed, and the above units or components may also be combined as needed.

[0096] By using the blade stall identification method and device of a wind turbine generator set and a computer-readable storage medium computing device according to the embodiments of the present disclosure, at least one of the following technical effects can be achieved: it can simply and effectively determine in real time online whether the cause of the abnormal output power of the wind turbine generator set includes blade stall, and can timely and effectively avoid the hazards caused by blade stall, and solve the safety hazards existing in the operation of the wind turbine generator set; based on the judgment result, timely intervention can be made in the operation of the wind turbine generator set, and then the risks of blade breakage caused by blade stall can be timely and effectively eliminated, thereby ensuring the safe operation of the wind turbine generator set.

[0097] The control logic or function executed by each component or controller in the control system can be represented by a flow chart or similar diagram in one or more accompanying drawings. These drawings provide representative control strategies and / or logic, which can be implemented using one or more processing strategies (such as, event-driven, interrupt-driven, multi-tasking, multi-threading, etc.). Therefore, the various steps or functions shown can be executed in the order shown, performed in parallel, or omitted in some cases. Although not always clearly shown, it will be appreciated by those of ordinary skill in the art that the one or more steps or functions shown can be repeatedly executed according to the specific processing strategy used.

[0098] While the present disclosure has been shown and described with reference to preferred embodiments, it will be understood by those skilled in the art that various modifications and variations can be made in these embodiments without departing from the spirit and scope of the disclosure as defined by the appended claims.

Claims

1. A method for identifying blade stall of a wind turbine generator set, characterized in that: The blade stall identification method comprises: Identify abnormal output power of wind turbines; In response to identifying an output power anomaly of the wind turbine generator set, controlling the wind turbine generator set to perform pitch change, wherein controlling the wind turbine generator set to perform pitch change includes: increasing the pitch angle of the blades of the wind turbine generator set by a predetermined amplitude, and maintaining the increased pitch angle until a predetermined time period ends, wherein the predetermined amplitude is set according to a severity level of the output power anomaly, or obtaining a blade angle of attack when the output power anomaly is identified, and setting the predetermined amplitude according to the obtained blade angle of attack and a predetermined stall angle of attack; Acquiring operating parameters of the wind turbine generator set within the predetermined time period after starting the pitch change; According to the change of the operating parameter within the predetermined time period, it is identified whether the cause of the output power abnormality includes blade stall.

2. The blade stall identification method according to claim 1, characterized in that: The inflow angle of the blades of the wind turbine generator set remains unchanged during the predetermined time period.

3. The blade stall identification method according to claim 1, characterized in that: Setting the predetermined amplitude according to the acquired blade angle of attack and the predetermined stall angle of attack includes: setting the predetermined amplitude according to the acquired blade angle of attack, the predetermined stall angle of attack, and a predetermined adjustment value.

4. The blade stall identification method according to any one of claims 1 to 3, characterized in that: Identifying the abnormality in the output power of the wind turbine generator set includes: identifying the abnormality in the output power of the wind turbine generator set according to a ratio between the actual output power of the wind turbine generator set and the maximum output power at a corresponding wind speed.

5. The blade stall identification method according to claim 4, characterized in that: Identifying an output power abnormality of a wind turbine generator set based on a ratio between the actual output power of the wind turbine generator set and the maximum output power at a corresponding wind speed includes: identifying an output power abnormality of the wind turbine generator set in response to the ratio between the actual output power of the wind turbine generator set and the maximum output power at a corresponding wind speed being less than or equal to a predetermined ratio.

6. The blade stall identification method according to claim 5, characterized in that: The predetermined ratio includes a plurality of predetermined ratios, each of which corresponds to a plurality of predetermined severity levels. Identifying an output power anomaly of a wind turbine generator set based on the ratio between the actual output power of the wind turbine generator set and the maximum output power at the corresponding wind speed also includes: determining the severity level of the identified output power anomaly by comparing the ratio between the actual output power of the wind turbine generator set and the maximum output power at the corresponding wind speed with the multiple predetermined ratios respectively.

7. The blade stall identification method according to any one of claims 1 to 3, characterized in that: Identifying, based on the change of the operating parameter within the predetermined time period, whether the cause of the abnormal output power includes blade stall includes: identifying whether the change in the operating parameter within the predetermined time period includes an increase; In response to the change in the operating parameter within the predetermined time period including an increase, it is determined that the cause of the output power abnormality includes blade stall.

8. The blade stall identification method according to claim 7, characterized in that: Identifying whether the change in the operating parameter within the predetermined time period includes an increase includes: Obtaining a maximum change value of the operating parameter within the predetermined time period; In response to the maximum change value being greater than or equal to a predetermined change threshold, it is determined that the change in the operating parameter within the predetermined time period includes an increase.

9. The blade stall identification method according to any one of claims 1 to 3, characterized in that: The operating parameters include at least one of the following items: blade speed, output power, power generation, and wind energy absorption of the wind turbine generator set.

10. The blade stall identification method according to any one of claims 1 to 3, characterized in that: The blade stall identification method further includes: In response to identifying that the cause of the output power abnormality includes blade stall, outputting a blade stall warning, and / or executing a protection operation corresponding to the blade stall; In response to identifying that the cause of the output power abnormality does not include blade stall, a non-blade stall warning is output, and / or a protection operation corresponding to non-blade stall is performed.

11. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the blade stall identification method according to any one of claims 1 to 10 is implemented.

12. A computing device, characterized in that: The computing device comprises: processor; A memory storing a computer program, wherein when the computer program is executed by a processor, the blade stall identification method according to any one of claims 1 to 10 is implemented.

13. A blade stall identification device for a wind turbine generator set, characterized in that: The blade stall identification device comprises: an output power abnormality identification unit configured to identify abnormalities in the output power of the wind turbine generator set; a pitch control unit configured to, in response to identifying an output power anomaly of the wind turbine generator set, control the wind turbine generator set to perform pitch change, wherein controlling the wind turbine generator set to perform pitch change comprises: increasing the pitch angle of the blades of the wind turbine generator set by a predetermined amplitude, and keeping the increased pitch angle unchanged until a predetermined time period ends, wherein the predetermined amplitude is set according to a severity level of the output power anomaly, or obtaining a blade angle of attack when the output power anomaly is identified, and setting the predetermined amplitude according to the obtained blade angle of attack and a predetermined stall angle of attack; The blade stall identification unit is configured to obtain operating parameters of the wind turbine generator set within the predetermined time period after the pitch change is started; and identify whether the cause of the output power abnormality includes blade stall based on changes in the operating parameters within the predetermined time period.

14. The blade stall identification device according to claim 13, characterized in that: The inflow angle of the blades of the wind turbine generator set remains unchanged during the predetermined time period.

15. The blade stall identification device according to claim 13, characterized in that: The pitch control unit is configured to set the predetermined amplitude according to the acquired blade angle of attack, the predetermined stall angle of attack, and the predetermined adjustment value.

16. The blade stall identification device according to any one of claims 13 to 15, characterized in that: The output power abnormality identification unit is configured to identify the output power abnormality of the wind generator set according to the ratio between the actual output power of the wind generator set and the maximum output power at the corresponding wind speed.

17. The blade stall identification device according to claim 16, characterized in that: The output power abnormality identification unit is configured to: in response to a ratio between the actual output power of the wind generator set and the maximum output power at the corresponding wind speed being less than or equal to a predetermined ratio, identify an output power abnormality of the wind generator set.

18. The blade stall identification device according to claim 17, characterized in that: The predetermined ratio includes a plurality of predetermined ratios, each of which corresponds to a plurality of predetermined severity levels. The output power anomaly identification unit is configured to determine the severity level of the identified output power anomaly by comparing the ratio between the actual output power of the wind turbine generator set and the maximum output power at the corresponding wind speed with the multiple predetermined ratios.

19. The blade stall identification device according to any one of claims 13 to 15, characterized in that: The output power abnormality identification unit is configured to: identifying whether the change in the operating parameter within the predetermined time period includes an increase; In response to the change in the operating parameter within the predetermined time period including an increase, it is determined that the cause of the output power abnormality includes blade stall.

20. The blade stall identification device according to claim 19, characterized in that: The blade stall identification unit is configured to: Obtaining a maximum change value of the operating parameter within the predetermined time period; In response to the maximum change value being greater than or equal to a predetermined change threshold, it is determined that the change in the operating parameter within the predetermined time period includes an increase.

21. The blade stall identification device according to any one of claims 13 to 15, characterized in that: The operating parameters include at least one of the following items: blade speed, output power, power generation, and wind energy absorption of the wind turbine generator set.

22. The blade stall identification device according to any one of claims 13 to 15, characterized in that: The blade stall identification device further includes an execution protection unit, which is configured to: In response to identifying that the cause of the output power abnormality includes blade stall, outputting a blade stall warning, and / or executing a protection operation corresponding to the blade stall; In response to identifying that the cause of the output power abnormality does not include blade stall, a non-blade stall warning is output, and / or a protection operation corresponding to non-blade stall is performed.

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