A control method for blade angle deviation fault based on inverse time

Abstract

The application discloses a control method for blade angle deviation fault based on reverse time limit, which pre-sets a starting threshold and a maximum blade deviation value, starts control calculation for the blade angle deviation fault based on the reverse time limit when the blade angle deviation value reaches the starting threshold, triggers a blade angle deviation fault protection action immediately when the blade angle deviation value reaches or exceeds the maximum blade deviation value, and formulates a reverse time limit curve based on the starting threshold and the maximum blade deviation value; the blade angle deviation value detected in real time is judged for deviation severity according to the reverse time limit curve, and the time for triggering the blade angle deviation fault protection action is dynamically adjusted according to the severity of the deviation; the application can quickly and effectively remove the fault, ensures the safe operation of the fan, improves the protection range of the blade deviation fault, and improves the reliability of the wind turbine generator set.

Description

Technical Field

[0001] This invention belongs to the field of wind power generation control, specifically relating to a blade angle deviation fault control method based on inverse time. Background Technology

[0002] In wind power generation control systems, large deviations in the three blades of a wind turbine (also known as "blade angle deviation fault") can significantly reduce power generation efficiency, cause stress concentration in components such as wind turbine blades and main shaft bearings, accelerate material fatigue, and increase tower vibration, thus affecting the stability of the entire wind turbine generator set.

[0003] In current technology, the method for identifying blade angle deviation faults uses time-limited logic. That is, a trigger value and a delay time are set in the time-limited logic. When the deviation value reaches or exceeds the trigger value, an alarm mechanism for "blade angle deviation fault" is triggered after a certain delay. If the deviation value is less than the trigger value, the alarm mechanism will not be triggered. This blade angle deviation fault control scheme based on time-limited logic has the following main problems:

[0004] 1. It is impossible to distinguish the severity of the fault. The time limit logic does not execute the protection logic when the deviation of the three blades is lower than the set value. However, the wind turbine may already be in an abnormal state at this time, and if it continues for too long, it will also affect the wind turbine.

[0005] 2. Parameter setting is difficult. Protection requires setting setpoints and delay values. If the parameters are not set properly, it may cause malfunctions or failure to operate.

[0006] 3. Inability to distinguish between persistent and transient faults, leading to unnecessary failures.

[0007] Therefore, the applicant seeks technical solutions to improve the above-mentioned technical problems. Summary of the Invention

[0008] In view of this, the purpose of this invention is to propose a control method for blade angle deviation faults based on inverse time limits. This method dynamically adjusts the triggering time of blade angle deviation fault protection actions according to the severity of the deviation. Specifically, the larger the blade deviation, the shorter the response time, enabling rapid and effective fault clearing and ensuring the safe operation of the wind turbine. When the deviation is severe, the protection logic is triggered quickly (which can manifest as alarms, shutdowns, etc.). Furthermore, by setting a start threshold, it is ensured that even with minor faults, there will be no overreaction like existing time-limited alarm mechanisms, thus improving the protection range of blade deviation faults and enhancing the reliability of wind turbine generator sets.

[0009] Therefore, the technical solution adopted by the present invention is as follows:

[0010] A control method for blade angle deviation fault based on inverse time is provided. A trigger threshold and a maximum blade deviation value are pre-set. When the blade angle deviation value reaches at least the trigger threshold, control calculations based on inverse time for the blade angle deviation fault are initiated. When the blade angle deviation value reaches or exceeds the maximum blade deviation value, a blade angle deviation fault protection action is immediately triggered. An inverse time curve is generated based on the trigger threshold and the maximum blade deviation value. The severity of the detected blade angle deviation value is judged according to this inverse time curve, and the triggering time for the blade angle deviation fault protection action is dynamically adjusted according to the severity of the deviation.

[0011] Preferably, the horizontal axis of the inverse time-delay curve represents the time when the blade angle deviation fault protection action is triggered, and the vertical axis represents the blade angle deviation value, which is obtained by fitting an exponential function.

[0012] Preferably, in the inverse time curve, the coordinate corresponding to the start-up threshold is (t1, start-up threshold), and the coordinate corresponding to the maximum blade deviation value is (t2, maximum blade deviation value). The inverse time curve passes through both of these coordinates. Wherein, t1 is the time corresponding to triggering the blade angle deviation fault protection action when the blade angle deviation value reaches the start-up threshold in the inverse time curve; t2 is the time corresponding to triggering the blade angle deviation fault protection action when the blade angle deviation value reaches the maximum blade deviation value in the inverse time curve.

[0013] Preferably, the exponential function is in the form of:

[0014] ;in,

[0015] t represents the time when the blade angle deviation fault protection action is triggered; θ represents the real-time detected blade angle deviation value; A, B and C are the matching fitting parameters, with (t1, start threshold) and (t2, maximum blade deviation value) as the fitting matching principle.

[0016] Preferably, the range of t1 is set to 50-150 seconds, more preferably 80-120 seconds; and / or the range of t2 is set to 0-0.5 seconds, more preferably 0-0.1 seconds, and even more preferably 0 seconds.

[0017] Preferably, the range of the start-up threshold is set to 0.2-1°, more preferably 0.3-0.8°, and even more preferably 0.4-0.6°; and / or the range of the maximum blade deviation value is set to 3-8°, more preferably 4-6°.

[0018] Preferably, after the blade angle deviation value reaches the activation threshold, the severity of the deviation is judged. When judging the severity of the deviation, the inverse time curve is used as the target. The real-time detected blade angle deviation value is compared with the intersection point of the inverse time curve. The time corresponding to the adjustment triggering the blade angle deviation fault protection action is determined based on the intersection point. Thus, the time for triggering the blade angle deviation fault protection action is dynamically adjusted according to the severity of the deviation.

[0019] Preferably, the control calculation process used in judging the severity of the deviation is as follows:

[0020] The squared values ​​of the real-time detected blade angle deviations are multiplied by the time step, and the sum is accumulated to obtain the deviation integral. The calculation formula is as follows:

[0021] devErrorSum1+= dev * dev * dt; where dev is the real-time detected blade angle deviation value, dt is the time step, which is the cumulative duration within the calculation cycle; devErrorSum1 is the deviation integral calculated cumulatively within the calculation cycle;

[0022] The deviation integral is compared with the alarm setting threshold (BladeDeviationIntegral): when the deviation integral reaches or exceeds the alarm setting threshold, the blade angle deviation fault protection action is triggered; when the deviation integral exceeds the alarm setting threshold, the blade angle deviation fault protection action is triggered; when it is less than the alarm setting threshold, the deviation integral is cleared to zero and the next calculation cycle begins.

[0023] Preferably, the alarm setting threshold (BladeDeviationIntegral) is dynamically adjusted based on the inverse time limit curve.

[0024] Preferably, the blade angle deviation fault protection action includes issuing a blade angle deviation fault alarm signal; wherein, the step of dynamically adjusting the timing of triggering the blade angle deviation fault protection action according to the severity of the deviation includes:

[0025] The larger the real-time detected blade angle deviation value, the shorter the time required to trigger the blade angle deviation fault protection action.

[0026] It should be noted that the blade deviation mentioned in this application refers to the angular deviation of the three blades. The detection of the angular deviation of the three blades is common knowledge in the field and is not an innovative content of this application. This application will not elaborate on this in detail.

[0027] This invention proposes a blade deviation fault protection logic control scheme based on inverse time-limited logic, optimizing the traditional blade deviation fault logic. Specifically, it introduces inverse time-limited logic control into the blade deviation fault triggering logic control, and specifically develops an inverse time-limited curve. Based on this curve, the severity of the deviation is judged, and the triggering time for the blade angle deviation fault protection action is dynamically adjusted according to the severity of the deviation. Specifically, the larger the blade deviation, the shorter the response time, enabling rapid and effective fault clearing and ensuring the safe operation of the wind turbine. In cases of severe deviation, the protection logic is quickly triggered (which can manifest as alarms, shutdowns, etc.). Furthermore, by setting a trigger threshold, it ensures that even with minor faults, there will be no overreaction like existing time-limited alarm mechanisms, thus improving the protection range of blade deviation faults and enhancing the reliability of wind turbine generators. Attached Figure Description

[0028] Figure 1 This is the inverse time limit curve diagram set in the specific implementation of this application. Detailed Implementation

[0029] This invention discloses a control method for blade angle deviation fault based on inverse time. A start threshold and a maximum blade deviation value are preset. Once the blade angle deviation value reaches at least the start threshold, control calculations for the blade angle deviation fault based on inverse time are initiated. When the blade angle deviation value reaches or exceeds the maximum blade deviation value, a blade angle deviation fault protection action is immediately triggered. An inverse time curve is formulated based on the start threshold and the maximum blade deviation value. The severity of the detected blade angle deviation value is judged according to this inverse time curve, and the timing of triggering the blade angle deviation fault protection action is dynamically adjusted based on the severity of the deviation.

[0030] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0031] This embodiment proposes a control method for blade angle deviation faults based on inverse time. A start threshold and a maximum blade deviation value are preset. Once the blade angle deviation value reaches at least the start threshold, control calculations for the blade angle deviation fault based on inverse time are initiated. When the blade angle deviation value reaches or exceeds the maximum blade deviation value, a blade angle deviation fault protection action is immediately triggered. An inverse time curve is established based on the start threshold and the maximum blade deviation value. The severity of the detected blade angle deviation value is judged according to this inverse time curve, and the timing of triggering the blade angle deviation fault protection action is dynamically adjusted according to the severity of the deviation. Preferably, the blade angle deviation fault protection action includes issuing a blade angle deviation fault alarm signal. In this embodiment, dynamically adjusting the timing of triggering the blade angle deviation fault protection action according to the severity of the deviation includes: the larger the detected blade angle deviation value, the shorter the corresponding triggering time for the blade angle deviation fault protection action.

[0032] Preferably, in this embodiment, the horizontal axis of the inverse time curve represents the time at which the blade angle deviation fault protection is triggered, and its vertical axis represents the blade angle deviation value, obtained by fitting an exponential function; more preferably, in this embodiment, the form of the exponential function is:

[0033] ;in,

[0034] t represents the time when the blade angle deviation fault protection action is triggered; θ represents the real-time detected blade angle deviation value; A, B and C are the matching fitting parameters, with (t1, start threshold) and (t2, maximum blade deviation value) as the fitting matching principle;

[0035] Preferably, in this embodiment, in the inverse time curve, the coordinate corresponding to the start threshold is (t1, start threshold), and the coordinate corresponding to the maximum blade deviation value is (t2, maximum blade deviation value). The inverse time curve passes through both of these coordinates. Wherein, t1 is the time when the blade angle deviation value reaches the start threshold in the inverse time curve, corresponding to the triggering of the blade angle deviation fault protection action; t2 is the time when the blade angle deviation value reaches the maximum blade deviation value in the inverse time curve, corresponding to the triggering of the blade angle deviation fault protection action.

[0036] More preferably, in this embodiment, the range of t1 is set to 50-150 seconds, more preferably 80-120 seconds; and / or the range of t2 is set to 0-0.5 seconds, more preferably 0-0.1 seconds, and even more preferably 0 seconds; the range of the start-up threshold is set to 0.2-1°, more preferably 0.3-0.8°, and even more preferably 0.4-0.6°; and / or the range of the maximum blade deviation value is set to 3-8°, more preferably 4-6°;

[0037] Specifically, in this embodiment, t1 is set to 100 seconds, t2 is set to 0 seconds, the start-up threshold is set to 0.5°, and the maximum blade deviation is set to 5°. Correspondingly, in this embodiment, in the inverse time curve, the coordinates corresponding to the start-up threshold are (100, 0.5), and the coordinates corresponding to the maximum blade deviation are (0, 5). Please refer to the specific inverse time curve obtained by matching and fitting. Figure 1 As shown.

[0038] Preferably, in this embodiment, after the blade angle deviation value reaches the activation threshold, the severity of the deviation is judged. When judging the severity of the deviation, the inverse time curve is used as the target. The real-time detected blade angle deviation value is compared with the coordinate intersection point of the inverse time curve. Based on this coordinate intersection point, the corresponding time for triggering the blade angle deviation fault protection action is determined. Thus, the timing of triggering the blade angle deviation fault protection action is dynamically adjusted according to the severity of the deviation. Preferably, in this embodiment, different deviation fault protection actions can also be triggered according to the severity of the deviation. For example, when the deviation exceeds the maximum blade deviation value, a shutdown protection can be immediately executed.

[0039] Please see Figure 1 As shown, Figure 1 The “Inverse-Time Curve” marked in the middle represents the inverse-time curve designed in this specific embodiment. The horizontal axis of the inverse-time curve, Actio time, represents the time when the blade angle deviation fault protection action is triggered, in seconds (s), and the value range is 0~500; its vertical axis, Angle Deviation, represents the blade angle deviation value, in degrees (°), and the value range is 0.5~5 degrees.

[0040] exist Figure 1 In the diagram, the two red "Points" represent two coordinate points that pass through the inverse time-limit curve. The coordinate point (0, 5) corresponds to the maximum blade deviation value, which means that when the blade angle deviation reaches 5°, the blade angle deviation fault protection action is triggered instantly (specifically, an alarm signal is issued and the machine is stopped), without any delay. The coordinate point (100, 0.5) corresponds to the activation threshold, which means that if the blade angle deviation value reaches 0.5 degrees, the blade angle deviation fault protection action is triggered with a delay of 100 seconds.

[0041] exist Figure 1In the diagram, the orange diagonal line Linear 1 and the green diagonal line Linear 2 represent two operating conditions with different real-time detected blade angle deviation values. The intersection point with the inverse time curve is the action point (i.e., the triggering of the blade angle deviation fault protection action). Specifically, the orange diagonal line has a larger deviation, and the corresponding fault triggering time (i.e., the time to trigger the blade angle deviation fault protection action) is shorter. The green diagonal line has a smaller angle deviation, and the corresponding fault triggering time (i.e., the time to trigger the blade angle deviation fault protection action) is longer.

[0042] The horizontal dashed line with y=0.5 represents the start-up threshold. Only when the blade deviation angle is equal to or greater than 0.5° will the inverse time-limit curve logic control provided in this embodiment be entered.

[0043] Therefore, we can confirm that in the inverse time-delay curve provided in this embodiment, the corresponding fault trigger time is different for different degrees of fault, for example, in Figure 1 The fault trigger time corresponding to the orange diagonal line Linear 1 shown is significantly shorter than that corresponding to the green diagonal line Linear 2. This embodiment introduces inverse time-limit curve control in the fault logic judgment, making the fault trigger time more flexible and realizing dynamic adjustment according to the severity of the deviation, and also providing protection for minor deviation faults.

[0044] Further preferably, in order to achieve the determination of deviation severity based on the inverse time-limit curve and the dynamic adjustment of the triggering time for blade angle deviation fault protection based on the severity of the deviation as described in the above embodiments of this application, the control calculation process adopted in this embodiment is as follows:

[0045] The squared values ​​of the real-time detected blade angle deviations are multiplied by the time step, and the sum is accumulated to obtain the deviation integral. The calculation formula is as follows:

[0046] devErrorSum1+= dev * dev * dt; where dev is the real-time detected blade angle deviation value, dt is the time step, which is the cumulative duration within the calculation cycle; devErrorSum1 is the deviation integral calculated cumulatively within the calculation cycle;

[0047] The deviation integral is compared with the alarm set threshold (BladeDeviationIntegral), which is dynamically adjusted based on an inverse time-limit curve: when the deviation integral reaches or exceeds the alarm set threshold, the blade angle deviation fault protection action is triggered; when the deviation integral exceeds the alarm set threshold, the blade angle deviation fault protection action is triggered; when it is less than the alarm set threshold, the deviation integral is cleared to zero, and the next calculation cycle begins; see also... Figure 1 As shown, Figure 1 The red "Action Zone" represents the active scanning area for comparing the deviation integral in the control calculation, while the purple "Inhibition Zone" represents the alarm protection triggered when the control calculation exceeds the alarm threshold set by the inverse time curve.

[0048] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0049] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A control method for blade angle deviation fault based on inverse time limitation, characterized in that, A pre-set start threshold and maximum blade deviation value are established. When the blade angle deviation value reaches at least the start threshold, control calculations for blade angle deviation faults based on inverse time are initiated. When the blade angle deviation value reaches or exceeds the maximum blade deviation value, a blade angle deviation fault protection action is immediately triggered. An inverse time curve is established based on the start threshold and maximum blade deviation value. The severity of the detected blade angle deviation value is judged according to the inverse time curve, and the timing of triggering the blade angle deviation fault protection action is dynamically adjusted according to the severity of the deviation. The horizontal axis of the inverse time curve represents the time when the blade angle deviation fault protection action is triggered, and the vertical axis represents the blade angle deviation value, which is obtained by fitting an exponential function. In the inverse time curve, the coordinate corresponding to the start-up threshold is (t1, start-up threshold), and the coordinate corresponding to the maximum blade deviation value is (t2, maximum blade deviation value). The inverse time curve passes through both of these coordinates. Here, t1 is the time corresponding to the triggering of the blade angle deviation fault protection action when the blade angle deviation value reaches the start-up threshold in the inverse time curve; t2 is the time corresponding to the triggering of the blade angle deviation fault protection action when the blade angle deviation value reaches the maximum blade deviation value in the inverse time curve. The exponential function takes the form of: ;in, t represents the time when the blade angle deviation fault protection action is triggered; θ represents the real-time detected blade angle deviation value; A, B and C are the matching fitting parameters, with (t1, start threshold) and (t2, maximum blade deviation value) as the fitting matching principle; The blade angle deviation fault protection action includes issuing a blade angle deviation fault alarm signal; wherein, the dynamic adjustment of the triggering time for the blade angle deviation fault protection action according to the severity of the deviation includes: The larger the real-time detected blade angle deviation value, the shorter the time required to trigger the blade angle deviation fault protection action.

2. The control method for blade angle deviation fault based on inverse time as described in claim 1, characterized in that, The range of t1 is set to 50-150 seconds; and / or the range of t2 is set to 0-0.5 seconds.

3. The control method for blade angle deviation fault based on inverse time as described in claim 1 or 2, characterized in that, The range of the start-up threshold is set to 0.2-1°; and / or the range of the maximum blade deviation value is set to 3-8°.

4. The control method for blade angle deviation fault based on inverse time as described in claim 1, characterized in that, Once the blade angle deviation value reaches the activation threshold, the severity of the deviation is assessed. During the severity assessment, the inverse time curve is used as the target. The real-time detected blade angle deviation value is compared with the intersection point of the inverse time curve. Based on the intersection point, the corresponding time for triggering the blade angle deviation fault protection action is determined. Thus, the timing of triggering the blade angle deviation fault protection action is dynamically adjusted according to the severity of the deviation.

5. The control method for blade angle deviation fault based on inverse time as described in claim 4, characterized in that, The control calculation process used to determine the severity of the deviation is as follows: The squared values ​​of the real-time detected blade angle deviations are multiplied by the time step, and the sum is accumulated to obtain the deviation integral. The calculation formula is as follows: devErrorSum1+= dev × dev × dt; where dev is the real-time detected blade angle deviation value, dt is the time step, which is the cumulative duration within the calculation cycle; devErrorSum1 is the deviation integral calculated cumulatively within the calculation cycle. The deviation integral is compared with the alarm setting threshold (BladeDeviationIntegral): when the deviation integral reaches or exceeds the alarm setting threshold, the blade angle deviation fault protection action is triggered; when the deviation integral is less than the alarm setting threshold, the deviation integral is cleared to zero and the next calculation cycle begins.

6. The control method for blade angle deviation fault based on inverse time as described in claim 5, characterized in that, The alarm setting threshold (BladeDeviationIntegral) is dynamically adjusted based on the inverse time limit curve.

Images