Wind generating set rotating speed abnormal value filtering method and device and wind generating set

Abstract

The invention discloses a wind generating set rotating speed abnormal value filtering method and device and a wind generating set, and the method comprises the steps: obtaining a current rotating speed measurement value, and calculating an absolute difference value between the current rotating speed measurement value and a filtering output value of a last period; if the absolute difference is larger than or equal to a first preset threshold value and the value of the abnormal counter is larger than zero, the current rotating speed measurement value is judged as abnormal jump data, the filtering output value is kept as the filtering output value of the last period, and meanwhile one is subtracted from the value of the abnormal counter; if the absolute difference value is smaller than or equal to a second preset threshold value, the current rotating speed measurement value is judged to be normal fluctuation data, the current rotating speed measurement value is adopted as the filtering output value, and the abnormal counter is reset to be a preset reset value; and if the absolute difference value is greater than the second preset threshold value and less than the first preset threshold value, adjusting at a preset step length according to the change direction of the current rotating speed measurement value relative to the filtering output value of the previous period to obtain the filtering output value. The problem of shutdown caused by abnormal jump of the rotating speed signal of the wind generating set is solved.

Description

Technical Field

[0001] This invention belongs to the field of wind turbine technology, specifically relating to a method, device and wind turbine generator set for filtering outdated speed values. Background Technology

[0002] In the field of wind power technology, the accuracy of speed measurement directly affects the stable operation of wind turbine generators. This signal is mainly used for overspeed protection and drivetrain failure protection, and is a key parameter to ensure the safe operation of the unit. Abnormal fluctuations in the speed signal are a common problem in the industry. These fluctuations are not caused by traditional sensor failures or electromagnetic interference, making conventional hardware troubleshooting difficult to resolve effectively. When frequent and large fluctuations occur, the fluctuating speed signal can easily trigger overspeed protection, leading to unit shutdown and impacting power generation efficiency.

[0003] Therefore, it is necessary to develop a new method, device, and wind turbine generator set for filtering outdated speed values. Summary of the Invention

[0004] The purpose of this invention is to provide a method, device and wind turbine generator set for filtering abnormal speed values, which can solve the shutdown problem caused by abnormal jumps in the speed signal of wind turbine generator sets.

[0005] In a first aspect, the present invention provides a method for filtering abnormal speed values ​​of a wind turbine generator set, comprising the following steps: Obtain the current speed measurement value and calculate the absolute difference between the current speed measurement value and the filter output value of the previous cycle; If the absolute difference is greater than or equal to the first preset threshold and the value of the abnormal counter is greater than zero, then the current speed measurement value is determined to be abnormal jump data, the filter output value is kept as the filter output value of the previous cycle, and the abnormal counter value is decremented by one. If the absolute difference is less than or equal to the second preset threshold, the current speed measurement value is determined to be normal fluctuation data, the filtered output value adopts the current speed measurement value, and the abnormal counter is reset to the preset reset value, wherein the first preset threshold is greater than the second preset threshold; If the absolute difference is less than the first preset threshold and greater than the second preset threshold, then the filtered output value is adjusted by a preset step size according to the direction of change of the current speed measurement value relative to the filtered output value of the previous cycle. That is, if the current speed measurement value is greater than the filtered output value of the previous cycle, the filtered output value is the filtered output value of the previous cycle plus the preset step size; if the current speed measurement value is less than the filtered output value of the previous cycle, the filtered output value is the filtered output value of the previous cycle minus the preset step size.

[0006] Optionally, the first preset threshold, the second preset threshold, and the preset step size are all determined based on the maximum value of the rotational speed change in adjacent cycles and the corresponding rotational speed jump factor, specifically: The first preset threshold is equal to the maximum change in speed between adjacent cycles × the maximum multiple of the speed jump, which is used to define the range of abnormal jumps and trigger the outlier removal mechanism. The second preset threshold = maximum speed change in adjacent cycles × speed jump factor, is used to define the normal fluctuation range and trigger the direct adoption mechanism; The preset step size = the maximum speed change in adjacent cycles × the speed jump factor, is used to determine the speed adjustment range in the transition range between normal and abnormal jumps; Among them, the maximum speed jump factor is greater than the speed jump factor.

[0007] Optionally, when the system starts up or the filtering method runs for the first time, the initial value of the filter value of the previous cycle is set to the current speed measurement value, the initial value of the abnormal counter is set to a preset value, and the current speed measurement value is used as the filter output value.

[0008] Optionally, when the abnormal counter value decreases to 0, if the absolute difference is detected to be greater than or equal to the first preset threshold again, the filtered output value is adjusted by the preset step size according to the direction of change of the current speed measurement value relative to the filtered output value of the previous cycle.

[0009] Secondly, the wind turbine generator set speed anomaly filtering device of the present invention includes a memory and a controller. The memory stores a computer-readable program. When the computer-readable program is called by a processor, it can execute the wind turbine generator set speed anomaly filtering method as described in the present invention.

[0010] Thirdly, the wind turbine generator set of the present invention employs the wind turbine generator set speed abnormality filtering device as described in the present invention.

[0011] The present invention has the following technical effects: This invention integrates a dual strategy of amplitude limiting and slope limiting, and employs a three-level judgment logic—abnormal jump rejection, direct sampling of normal fluctuations, and step size adjustment in the transition interval—to accurately distinguish between pulse-like noise and real dynamic changes in the wind turbine generator speed signal. Specifically, when the absolute difference between the current speed measurement value and the previous cycle's filtered output value is detected to be greater than a first preset threshold, the system classifies it as transient interference or abnormal data and rejects it to avoid false triggering of overspeed protection. Normal fluctuations with an absolute difference within a second preset threshold are directly adopted to ensure timely speed response. For real rapid changes between the two thresholds, a slope-limited progressive tracking is achieved with a preset step size, which avoids the phase lag problem of traditional low-pass filtering and maximizes the preservation of the dynamic characteristics of the speed signal. This invention effectively solves the problem of overspeed protection malfunction and unexpected shutdown caused by misjudgment of the speed signal in wind turbine generators, significantly improving the operational stability and power generation efficiency of wind turbine generators, and achieving an optimal balance between speed and stability under frequent and large speed jumps. Attached Figure Description

[0012] Figure 1 This is a flowchart of the wind turbine generator speed anomaly filtering method described in the embodiments of this application; Figure 2 This is a schematic diagram of the wind turbine generator speed anomaly filtering system described in the embodiments of this application; Figure 3 This is a schematic block diagram of the wind turbine generator set described in the embodiments of this application. Detailed Implementation

[0013] The embodiments of the present invention will be described below with reference to the accompanying drawings and preferred embodiments. Those skilled in the art can understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be understood that the preferred embodiments are only for illustrating the present invention and not for limiting the scope of protection of the present invention.

[0014] like Figure 1 As shown in the figure, this application discloses a method for filtering outlier values ​​in the rotational speed of a wind turbine generator set, including the following steps: Acquire the current speed measurement value and calculate the absolute difference between the current speed measurement value and the filtered output value of the previous cycle. If the absolute difference is greater than or equal to a first preset threshold and the abnormality counter value is greater than zero, the current speed measurement value is determined to be abnormal jump data, the filtered output value remains the filtered output value of the previous cycle, and the abnormality counter value is decremented by one. If the absolute difference is less than or equal to a second preset threshold, the current speed measurement value is determined to be normal fluctuation data, the filtered output value adopts the current speed measurement value, and the abnormality counter is reset to a preset reset value, where the first preset threshold is greater than the second preset threshold. If the absolute difference is less than the first preset threshold but greater than the second preset threshold, the filtered output value is adjusted by a preset step size according to the direction of change of the current speed measurement value relative to the filtered output value of the previous cycle. Save the current filtered output value as the benchmark for the next cycle calculation, completing this filtering operation.

[0015] This method integrates two strategies: amplitude limiting (i.e., limiting signal amplitude by defining a range through a threshold, with the core being the filtering of valid signals and the elimination of abnormal amplitudes) and slope limiting (i.e., adjusting the current speed measurement value through a preset step size to obtain the filtered output value). Through a three-level judgment mechanism, it achieves an effective balance between signal authenticity, smoothness, and response speed. Specifically, when a drastic speed jump far exceeding the expected range is detected (i.e., the absolute difference between the current speed measurement value and the filtered output value of the previous cycle is greater than or equal to a first preset threshold), the system classifies it as transient interference or abnormal data and eliminates it. To avoid masking true fault information due to continuous elimination, an upper limit is set for the number of eliminations (i.e., the initial value of the abnormality counter is set to a preset value, such as 3). For sampled values ​​within the normal range (i.e., when the absolute difference is less than or equal to a second preset threshold), the system directly adopts the sampled value to ensure a fast response. For rapidly changing but genuine signals (i.e., when the absolute difference is less than the first preset threshold but greater than the second preset threshold), this invention achieves progressive tracking through a preset step size, thereby avoiding the phase lag problem caused by traditional low-pass filtering. This invention not only effectively suppresses impulse noise but also preserves the dynamic characteristics of the signal to the maximum extent, achieving a good balance between speed and stability. This invention also solves the problem of wind turbine generators experiencing unexpected shutdowns due to overspeed protection triggered by frequent and large speed jumps, thus affecting power generation efficiency.

[0016] In this embodiment of the application, the filtered output value is obtained by adjusting with a preset step size, specifically as follows: If the current speed measurement value is greater than the filter output value of the previous cycle, the filter output value is the filter output value of the previous cycle plus a preset step size; if the current speed measurement value is less than the filter output value of the previous cycle, the filter output value is the filter output value of the previous cycle minus a preset step size.

[0017] In one possible embodiment, the first preset threshold, the second preset threshold, and the preset step size are all determined based on the maximum value of the rotational speed change in adjacent cycles and the corresponding rotational speed jump factor, specifically: The first preset threshold is equal to the maximum change in rotational speed between adjacent cycles multiplied by the maximum multiple of the rotational speed jump. This threshold is used to define the range of abnormal jumps and trigger the outlier removal mechanism.

[0018] The second preset threshold is calculated as the maximum change in rotational speed between adjacent cycles multiplied by the rotational speed jump factor. This threshold is used to define the normal fluctuation range and trigger the direct adoption mechanism.

[0019] The preset step size is calculated as the maximum speed change in adjacent cycles multiplied by the speed jump factor. It is used to determine the speed adjustment range in the transition zone between normal and abnormal jumps.

[0020] Among them, the maximum speed jump factor is greater than the speed jump factor.

[0021] In one possible embodiment, when the system starts up or the filtering method is run for the first time, the filter value of the previous cycle is initialized to the current speed measurement value, the initial value of the abnormality counter is set to a preset value, and the current speed measurement value is used as the filter output value.

[0022] In one possible embodiment, the initial value of the anomaly counter is set to a preset value to prevent loss of signal tracking due to continuous interference.

[0023] In one possible embodiment, when the abnormal counter value decreases to 0, if the absolute difference is detected again to be greater than or equal to the first preset threshold, the filtered output value is adjusted by a preset step size according to the direction of change of the current speed measurement value relative to the filtered output value of the previous cycle; specifically: if the current speed measurement value is greater than the filtered output value of the previous cycle, the filtered output value is the filtered output value of the previous cycle plus the preset step size; if the current speed measurement value is less than the filtered output value of the previous cycle, the filtered output value is the filtered output value of the previous cycle minus the preset step size.

[0024] like Figure 2 As shown in the embodiment of this application, a wind turbine generator speed anomaly filtering device includes a memory and a controller. The memory stores a computer-readable program. When the computer-readable program is called by the processor, it can execute the wind turbine generator speed anomaly filtering method of the present invention.

[0025] like Figure 3 As shown in the embodiments of this application, a wind turbine generator set adopts the wind turbine generator set speed abnormality filtering device as described in the embodiments of this application.

[0026] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. A wind turbine generator set rotational speed outlier filtering method, characterized by, The method comprises the following steps: obtaining a current rotation speed measurement value and calculating an absolute difference between the current rotation speed measurement value and a last period filter output value; if the absolute difference is greater than or equal to a first preset threshold value and a value of an abnormality counter is greater than zero, determining that the current rotation speed measurement value is abnormal jump data, keeping the filter output value as the last period filter output value, and reducing the value of the abnormality counter by one; if the absolute difference is less than or equal to a second preset threshold value, determining that the current rotation speed measurement value is normal fluctuation data, adopting the current rotation speed measurement value as the filter output value, and resetting the abnormality counter to a preset reset value, wherein the first preset threshold value is greater than the second preset threshold value; if the absolute difference is less than the first preset threshold value and greater than the second preset threshold value, adjusting the filter output value according to a change direction of the current rotation speed measurement value relative to the last period filter output value by a preset step, that is, if the current rotation speed measurement value is greater than the last period filter output value, the filter output value is the last period filter output value plus the preset step, and if the current rotation speed measurement value is less than the last period filter output value, the filter output value is the last period filter output value minus the preset step.

2. A wind turbine generator set rotational speed outlier filtering method according to claim 1, characterized by, The first preset threshold value, the second preset threshold value and the preset step are determined based on a maximum rotation speed change value of adjacent periods and a corresponding rotation speed jump multiple, and specifically: the first preset threshold value = the maximum rotation speed change value of adjacent periods × a maximum rotation speed jump multiple; the second preset threshold value = the maximum rotation speed change value of adjacent periods × a rotation speed jump multiple; the preset step = the maximum rotation speed change value of adjacent periods × the rotation speed jump multiple; wherein the maximum rotation speed jump multiple > the rotation speed jump multiple.

3. A wind turbine generator set rotational speed outlier filtering method according to claim 1, characterized by, When the system is started or the filter method is first run, a last period filter value is initialized as a current rotation speed measurement value currently read, an initial value of the abnormality counter is set as a preset value, and the current rotation speed measurement value is taken as a filter output value.

4. The wind turbine generator set rotational speed outlier filtering method according to claim 1, characterized by, When the value of the abnormality counter is reduced to 0, if the absolute difference is greater than or equal to the first preset threshold value again, the filter output value is adjusted according to the change direction of the current rotation speed measurement value relative to the last period filter output value by the preset step.

5. A wind turbine generator system rotational speed outlier filtering device, characterized by, The device comprises a memory and a controller, and the memory stores a computer readable program, which, when called by a processor, can execute the wind turbine rotation speed abnormal value filter method according to any one of claims 1 to 4.

6. A wind power unit, characterized in that The device adopts the wind turbine rotation speed abnormal value filter device according to claim 5.

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