CN113883014B

CN113883014B - Method, device and equipment for detecting unbalance of wind turbine generator impeller and storage medium

Info

Publication number: CN113883014B
Application number: CN202111243206.3A
Authority: CN
Inventors: 白淑华; 刘丽华; 梁家宁
Original assignee: Sany Renewable Energy Co Ltd
Current assignee: Sany Renewable Energy Co Ltd
Priority date: 2021-10-25
Filing date: 2021-10-25
Publication date: 2023-03-10
Anticipated expiration: 2041-10-25
Also published as: CN113883014A

Abstract

The invention provides a method, a device, equipment and a storage medium for detecting unbalance of an impeller of a wind turbine generator, wherein the method comprises the following steps: collecting operating data for a plurality of consecutive collection periods; and acquiring the first-order frequency conversion characteristic vector of the impeller of each group of operation data, constructing a characteristic vector group, and acquiring a pneumatic unbalance detection result and/or a mass unbalance detection result according to the characteristic vector group. The method combines the early warning logics of longitudinal trend analysis and transverse multi-channel fusion, adopts pneumatic unbalance detection mainly based on front and back vibration of the engine room, adopts mass unbalance detection mainly based on lateral vibration of the engine room and is supplemented with other associated channels with lower sensitivity, is more comprehensive compared with single-channel detection, and simultaneously combines the longitudinal trend analysis of a plurality of groups of operation data in a time domain range, can effectively reduce the misjudgment phenomenon of local abnormal points and improve the unbalance detection precision.

Description

Method, device and equipment for detecting unbalance of wind turbine generator impeller and storage medium

Technical Field

The invention relates to the technical field of intelligent detection, in particular to a method, a device, equipment and a storage medium for detecting unbalance of an impeller of a wind turbine generator.

Background

The wind turbine generator works in the field for a long time, the operation environment is usually severe, the failure rate of the wind turbine generator is high, the failure of the wind turbine generator is caused to be various, and the wind turbine generator mainly comprises blades, wherein the blades are unbalanced in quality due to wind sand, icing, uneven mass distribution and the like. In recent years, with the spread of low wind speed models, the length of the blade is increasing, and vibration caused by aerodynamic imbalance is receiving more and more attention from host manufacturers and owners. The long-term unbalance of the impeller not only influences the self power performance, but also causes great damage to other parts of the wind turbine. Therefore, the method has important significance in timely and accurately identifying the unbalanced fault of the impeller of the wind turbine generator.

In the prior art, when the unbalance of the impeller of the wind turbine generator is detected, the mass unbalance of the impeller is mainly detected according to the axial vibration (namely front and back vibration) of the impeller, but the practice proves that the axial vibration of part of the turbine is smaller under one-time rotation frequency, but when the rotation speed amplitude is larger, the pneumatic unbalance fault also exists, so that the axial vibration is considered to be more flakiness.

In addition, when the unbalance of the wind turbine generator impeller is detected in the prior art, a single-point early warning mode is generally adopted, that is, the operation data detected at a certain time point is independently analyzed, but due to the fact that individual abnormal points occur in actual operation, possible misjudgment of single-point early warning is inevitable.

In view of the above, it is desirable to improve the existing detection means to improve the accuracy of detecting the imbalance of the impeller.

Disclosure of Invention

The invention provides a method, a device, equipment and a storage medium for detecting the unbalance of an impeller of a wind turbine generator, which are used for solving the defect of low precision caused by single data in the process of detecting the unbalance of the impeller in the prior art.

In a first aspect, the present invention provides a wind turbine generator impeller imbalance detection method, including:

collecting operating data of the wind turbine generator in a plurality of continuous collecting time periods;

acquiring a first-order frequency conversion characteristic vector of the impeller corresponding to the running data in each acquisition time period to construct a characteristic vector group;

acquiring a pneumatic unbalance detection result and/or a mass unbalance detection result according to the feature vector group;

the pneumatic unbalance detection result is determined based on the comparison result of the amplitude of the front and rear vibration signals of the continuous K1 cabins and a first preset threshold;

and the mass unbalance detection result is determined based on the comparison result of the amplitude values of the continuous K2 cabin lateral vibration signals and a second preset threshold value.

According to the wind turbine generator impeller imbalance detection method provided by the invention, the operation data comprises at least one of the rotating speed of a main shaft or the rotating speed of a generator, the front and back vibration acceleration of a cabin and the lateral vibration acceleration of the cabin;

the obtaining of the first-order rotation frequency eigenvector of the impeller corresponding to the operation data in each acquisition period specifically includes:

acquiring a rotating speed power spectrum sequence pair according to the power spectrum density transformation of the rotating speed of the main shaft or the rotating speed of the generator in each acquisition time period;

performing fast Fourier transform on the front and rear vibration acceleration of the cabin in each acquisition time period to obtain a frequency spectrum sequence pair of the front and rear vibration amplitude of the cabin;

performing fast Fourier transform on the lateral vibration acceleration of the cabin in each acquisition time period to obtain a frequency spectrum sequence pair of lateral vibration amplitude of the cabin;

and determining a first-order rotation frequency characteristic vector of the impeller corresponding to each acquisition time period from the rotating speed power spectrum sequence pair, the cabin front and back vibration amplitude spectrum sequence pair and the cabin lateral vibration amplitude spectrum sequence pair respectively.

According to the method for detecting the imbalance of the impeller of the wind turbine generator, which is provided by the invention, the first-order rotating frequency characteristic vector of the impeller corresponding to each acquisition time period is determined from the rotating speed power spectrum sequence pair, the frequency spectrum sequence pair of the front and rear vibration amplitudes of the engine room and the frequency spectrum sequence pair of the lateral vibration amplitudes of the engine room respectively, and the method specifically comprises the following steps:

calculating initial frequency under one-time rotation frequency of the impeller according to the rotation speed of the main shaft or the rotation speed of the generator in each acquisition time period;

detecting first amplitude maxima in a first narrow-band range from the rotating speed power spectrum sequence pair, the cabin front and rear vibration amplitude spectrum sequence pair and the cabin lateral vibration amplitude spectrum sequence pair respectively, and determining the frequency corresponding to each first amplitude maximum;

taking the median of the frequencies corresponding to all the first amplitude maximum values as a reference frequency;

detecting second amplitude maximum values in a second narrow-band range from the rotating speed power spectrum sequence pair, the cabin front and back vibration amplitude spectrum sequence pair and the cabin lateral vibration amplitude spectrum sequence pair respectively, and constructing a first-order rotating frequency characteristic vector of the impeller by using the second amplitude maximum values;

the first narrow-band range is determined from the initial frequency, the second narrow-band range is determined from the reference frequency, and the first narrow-band range is greater than the second narrow-band range.

According to the method for detecting the unbalance of the impeller of the wind turbine generator, provided by the invention, a calculation formula for calculating the initial frequency of the impeller under one-time rotation frequency according to the rotation speed of the main shaft or the rotation speed of the generator in each acquisition time interval is as follows:

wherein f is _{1p_initial} Representing an initial frequency; ω _ rotor represents the spindle speed; ω _ gen represents generator speed; the SpeedRatio represents the transmission ratio of a speed increaser of the wind turbine generator; mean represents the geometric mean.

According to the wind turbine impeller imbalance detection method provided by the invention, a pneumatic imbalance detection result is determined based on a comparison result of amplitude values of front and rear vibration signals of continuous K1 cabins and a first preset threshold, and the method specifically comprises the following steps:

under the condition that the amplitude of the front and rear vibration signals of the continuous K1 engine rooms is not smaller than a first preset threshold value, if the amplitude of the front and rear vibration signals of the continuous K1 engine rooms is not smaller than a third preset threshold value, outputting the pneumatic unbalance detection result as a serious pneumatic unbalance fault, wherein the third preset threshold value is larger than the first preset threshold value;

under the condition that the amplitudes of the front and rear vibration signals of the continuous K1 engine rooms are not smaller than a first preset threshold value, if the amplitudes of the front and rear vibration signals of the continuous K1 engine rooms are smaller than a third preset threshold value and the amplitudes of the continuous K1 rotation speed signals are not smaller than a fourth preset threshold value, outputting the pneumatic unbalance detection result as a conventional pneumatic unbalance fault;

under the condition that the amplitude of the front and rear vibration signals of the continuous K1 engine rooms is not smaller than a first preset threshold value, if the amplitude of the front and rear vibration signals of the continuous K1 engine rooms is smaller than a third preset threshold value and the amplitude of the lateral vibration signals of the continuous K1 engine rooms is not smaller than a fifth preset threshold value, outputting the pneumatic unbalance detection result as a conventional pneumatic unbalance fault;

under the condition that the amplitudes of the front and rear vibration signals of the continuous K1 engine rooms are not smaller than a first preset threshold value, if the amplitudes of the front and rear vibration signals of the continuous K1 engine rooms are smaller than a third preset threshold value, the amplitudes of the continuous K1 rotation speed signals are smaller than a fourth preset threshold value, and the amplitudes of the lateral vibration signals of the continuous K1 engine rooms are smaller than a fifth preset threshold value, outputting the detection result of the pneumatic unbalance to be normal;

and outputting the detection result of the pneumatic unbalance to be normal when the amplitude of the front and rear vibration signals of the continuous K1 cabins is determined to be smaller than a first preset threshold value.

According to the wind turbine generator impeller imbalance detection method provided by the invention, the mass imbalance detection result is determined based on the comparison result of the amplitude values of the continuous K2 nacelle lateral vibration signals and the second preset threshold, and the method specifically comprises the following steps:

under the condition that the amplitudes of the continuous K2 machine cabin lateral vibration signals are not smaller than a second preset threshold value, if the amplitudes of the continuous K2 machine cabin lateral vibration signals are not smaller than a sixth preset threshold value, outputting the mass unbalance detection result as a serious mass unbalance fault, wherein the sixth preset threshold value is larger than the second preset threshold value;

under the condition that the amplitudes of the continuous K2 cabin lateral vibration signals are not smaller than a second preset threshold value, if the amplitudes of the continuous K2 cabin lateral vibration signals are smaller than a sixth preset threshold value, the amplitudes of the continuous K2 rotation speed signals are not smaller than a seventh preset threshold value, and the amplitudes of the continuous K2 cabin front and rear vibration signals are not larger than an eighth preset threshold value, outputting the mass unbalance detection result as a conventional pneumatic unbalance fault;

under the condition that the amplitudes of front and rear vibration signals of the continuous K2 engine rooms are not smaller than a second preset threshold value, if the amplitudes of lateral vibration signals of the continuous K2 engine rooms are smaller than a sixth preset threshold value and the amplitudes of continuous K2 rotating speed signals are smaller than a seventh preset threshold value, outputting the mass unbalance detection result as normal;

under the condition that the amplitudes of the front and rear vibration signals of the continuous K2 engine rooms are not smaller than a second preset threshold value, if the amplitudes of the lateral vibration signals of the continuous K2 engine rooms are smaller than a sixth preset threshold value, the amplitudes of the continuous K2 rotating speed signals are not smaller than a seventh preset threshold value, and the amplitudes of the front and rear vibration signals of the continuous K2 engine rooms are larger than an eighth preset threshold value, outputting the mass unbalance detection result as normal;

and outputting the mass unbalance detection result to be normal when the amplitude values of the continuous K2 cabin lateral vibration signals are determined to be smaller than a second preset threshold value.

According to the method for detecting the unbalance of the impeller of the wind turbine generator, provided by the invention, the operation data in a plurality of continuous acquisition time periods are acquired under the condition of the same rotating speed;

the same rotating speed condition means that the average rotating speed deviation of the wind turbine generator is smaller than a ninth preset threshold value in any two acquisition time periods.

In a second aspect, the present invention further provides a wind turbine generator impeller imbalance detection apparatus, including:

the data acquisition unit is used for acquiring the operating data of the wind turbine generator in a plurality of continuous acquisition time periods;

the data processing unit is used for acquiring a first-order conversion characteristic vector of the impeller corresponding to the operating data in each acquisition period so as to construct a characteristic vector group;

an imbalance detection unit cell is provided in the device,

the device is used for acquiring a pneumatic unbalance detection result and/or a mass unbalance detection result according to the feature vector group;

and the mass unbalance detection result is determined based on the comparison result of the amplitude values of the continuous K2 cabin lateral vibration signals and a second preset threshold value. In a third aspect, the present invention provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, where the processor executes the program to implement any of the steps of the wind turbine blade imbalance detection method described above.

In a fourth aspect, the present invention further provides a non-transitory computer-readable storage medium, on which a computer program is stored, which, when being executed by a processor, implements the steps of the wind turbine blade imbalance detection method according to any one of the above.

The method, the device, the equipment and the storage medium for detecting the imbalance of the impeller of the wind turbine generator set are combined with the early warning logic of longitudinal trend analysis and transverse multi-channel fusion, adopt pneumatic imbalance detection mainly based on front and back vibration of a cabin, adopt mass imbalance detection mainly based on lateral vibration of the cabin and are assisted by other associated channels with lower sensitivity, compared with single-channel detection, the method is more comprehensive, and simultaneously combined with the longitudinal trend analysis of multiple groups of running data in a time domain range, the method, the device, the equipment and the storage medium can effectively reduce the misjudgment phenomenon of local abnormal points and improve the accuracy of imbalance detection.

Drawings

In order to more clearly illustrate the technical solutions of the present invention or the prior art, the drawings needed for the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and those skilled in the art can also obtain other drawings according to the drawings without creative efforts.

FIG. 1 is a schematic flow diagram of a wind turbine blade imbalance detection method according to the present invention;

FIG. 2 is a second schematic flow chart of the method for detecting imbalance of an impeller of a wind turbine generator according to the present invention;

FIG. 3 is a schematic diagram of time-frequency waveforms of rotational speed and vibration signals under impeller balance provided by the present invention;

FIG. 4 is a schematic diagram of time-frequency waveforms of rotational speed and vibration signals under aerodynamic imbalance of an impeller according to the present invention;

FIG. 5 is a schematic diagram of time-frequency waveforms of rotational speed and vibration signals under the condition of unbalanced mass of the impeller provided by the invention;

FIG. 6 is a schematic flow diagram of the pneumatic imbalance detection provided by the present invention;

FIG. 7 is a schematic flow diagram of the mass imbalance detection provided by the present invention;

FIG. 8 is a schematic diagram illustrating the trend of the amplitudes at equilibrium for the impeller provided by the present invention;

FIG. 9 is a schematic view of the magnitude trend of the aerodynamic imbalance of the impeller provided by the present invention;

FIG. 10 is a graphical illustration of the magnitude trend for impeller mass imbalance provided by the present invention;

FIG. 11 is a schematic structural diagram of an unbalance detection device for an impeller of a wind turbine generator according to the present invention;

fig. 12 is a schematic structural diagram of an electronic device provided in the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings, and it is obvious that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It should be noted that in the description of the embodiments of the present invention, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising a … …" does not exclude the presence of another identical element in a process, method, article, or apparatus that comprises the element. The terms "upper", "lower", and the like, indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience in describing the present invention and simplifying the description, but do not indicate or imply that the referred devices or elements must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention. Unless expressly stated or limited otherwise, the terms "mounted," "connected," and "connected" are intended to be inclusive and mean, for example, that they may be fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

The terms first, second and the like in the description and in the claims of the present application are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It will be appreciated that the data so used may be interchanged under appropriate circumstances such that embodiments of the application may be practiced in sequences other than those illustrated or described herein, and that the terms "first," "second," and the like are generally used herein in a generic sense and do not limit the number of terms, e.g., the first term can be one or more than one. In addition, "and/or" in the specification and claims means at least one of connected objects, a character "/" generally means that a preceding and succeeding related objects are in an "or" relationship.

The method and the device for detecting the imbalance of the impeller of the wind turbine generator provided by the embodiment of the invention are described below with reference to fig. 1 to fig. 11.

Fig. 1 is a schematic flow diagram of a wind turbine blade imbalance detection method provided by the present invention, as shown in fig. 1, including but not limited to the following steps:

step 11: the method comprises the steps of collecting operating data of the wind turbine generator in a plurality of continuous collecting time periods.

Optionally, the operation data mainly refers to rotation speed information and vibration information of the wind turbine generator during operation, and a rotation speed sensor may be installed on a main shaft of the wind turbine generator or a generator to collect a rotation speed signal, so as to convert the rotation speed signal into rotation speed information; the method comprises the steps that a vibration sensor is installed at a relevant position of a cabin of the wind turbine generator to measure vibration signals of the wind turbine generator in the operation process, such as front and back vibration signals of the cabin and lateral vibration signals of the cabin, and then the converted front and back vibration acceleration and lateral vibration acceleration of the cabin are used as vibration information.

The front-back vibration of the engine room refers to the vibration of the engine room along the direction vertical to the fan surface of the wind turbine generator, and the lateral vibration of the engine room refers to the left-right vibration of the engine room along the direction of the fan surface of the wind turbine generator.

Compared with the prior art that the detection and analysis are only carried out on the operation data detected at a single time point when the wind turbine generator is in operation, the method and the device provided by the invention have the advantages that the operation data in a plurality of continuous time periods in the operation process of the wind turbine generator are collected, and the operation data in all the time periods are recorded and stored, so that data support is provided for longitudinal detection and analysis and trend early warning in the time domain at the later stage.

Optionally, the multiple continuous acquisition periods may be set according to actual detection accuracy requirements, configuration of data storage, and the like, for example: the method can take each day as an acquisition time interval, and take the operation data acquired each day in one month as a group, so as to realize the detection of the unbalance of the wind turbine impeller according to the group of operation data.

It should be noted that the operation data can be collected in real time, and the real-time detection of the unbalance of the impeller of the wind turbine generator is realized at the moment; the method for detecting the imbalance of the impeller of the wind turbine generator can also be used for detecting and analyzing historical data, and can provide a basis for fault analysis of the wind turbine generator according to an analysis result or provide experimental data for research and development design of the wind turbine generator.

Step 12: and acquiring a first-order frequency conversion eigenvector of the impeller corresponding to the operating data in each acquisition time period to construct an eigenvector group.

Each first-order rotation frequency characteristic vector of the impeller mainly comprises a front and back vibration signal amplitude, a rotation speed signal amplitude and a lateral vibration signal amplitude of the engine room under the condition that the rotation frequency of the impeller is one time.

After the operation data in a plurality of continuous acquisition periods are acquired, converting the operation data in each acquisition period from a time domain to a frequency domain, and acquiring the amplitude of the operation data according to the acquired corresponding frequency domain signal; then, constructing a first-order frequency conversion characteristic vector according to the amplitude of each signal, namely converting the operation data in each acquisition period into a first-order frequency conversion characteristic vector; finally, the first-order conversion feature vectors corresponding to the running data in each acquisition time interval are jointly assembled into a feature vector group, so that the signal component energy representing the degree of unbalance is extracted from the running data, and the impeller unbalance detection in the later period is more convenient.

Fig. 2 is a second schematic flow chart of the wind turbine blade imbalance detection method provided by the present invention, and as shown in fig. 2, the main shaft rotation speed signal (time domain signal) in any acquisition time period is subjected to time-frequency domain conversion to obtain a rotation speed amplitude spectrum sequence pair; carrying out time-frequency domain conversion on the vibration signals of the front and the back of the engine room in the acquisition time period to obtain a pair of frequency spectrum sequences of the vibration amplitudes of the front and the back; and carrying out time-frequency domain conversion on the lateral vibration signals of the cabin in the acquisition time period to obtain a lateral vibration amplitude spectrum sequence pair.

Further, impeller first-order frequency conversion feature extraction is respectively carried out on the rotating speed amplitude frequency spectrum sequence pair, the front-back vibration amplitude frequency spectrum sequence pair and the lateral vibration amplitude frequency spectrum sequence pair, so that corresponding first-order frequency conversion amplitude values (hereinafter referred to as 1p amplitude values) are respectively obtained, namely, a front-back vibration signal amplitude value (referred to as front-back vibration 1p amplitude value) of the engine room, a rotating speed signal amplitude value (referred to as rotating speed 1p amplitude value) and a lateral vibration signal amplitude value (referred to as lateral vibration 1p amplitude value) of the engine room can be obtained. Finally, a vector is formed by the three amplitudes, called the impeller first order beat feature vector (which may be a vector of 1*3). And finally, constructing the first-order rotation frequency eigenvectors of the impeller generated in all continuous acquisition periods into an eigenvector group, thereby realizing the fusion of the rotating speed and amplitude characteristics of the vibration signals related to the operation data in a plurality of continuous acquisition periods.

It should be noted that the feature vector set constructed by the present invention, on one hand, searches amplitude features (which can also be understood as having transverse multi-channel amplitude features) in the transverse direction from the rotation speed, the axial vibration of the nacelle, and the transverse vibration of the nacelle together; on the other hand, amplitude characteristic mining is carried out on the operation data in a plurality of continuous acquisition periods in the longitudinal direction, so that 1p amplitude characteristics of the rotating speed and the vibration signal for realizing the detection of the unbalance of the impeller are more comprehensive.

Step 13: acquiring a pneumatic unbalance detection result and/or a mass unbalance detection result according to the feature vector group;

It should be noted that the method for detecting the imbalance of the impeller of the wind turbine generator, provided by the invention, can be used for independently detecting the pneumatic imbalance of the impeller of the wind turbine generator, independently detecting the mass imbalance of the impeller of the wind turbine generator, and also can be used for combining the pneumatic imbalance detection with the mass imbalance detection according to the feature vector group corresponding to the constructed first-order frequency conversion feature vector of the impeller. For example: firstly, carrying out pneumatic unbalance detection, and then carrying out mass unbalance detection under the condition of determining that the pneumatic unbalance detection result is abnormal so as to comprehensively determine the reason for causing the unbalance of the wind turbine generator impeller.

Fig. 3 is a schematic diagram of time-frequency waveforms of rotational speed and vibration signals under the impeller balance provided by the present invention, fig. 4 is a schematic diagram of time-frequency waveforms of rotational speed and vibration signals under the impeller aerodynamic imbalance provided by the present invention, fig. 5 is a schematic diagram of time-frequency waveforms of rotational speed and vibration signals under the impeller mass imbalance provided by the present invention, and as shown in fig. 3, fig. 4 and fig. 5, three conditions of impeller balance, impeller aerodynamic imbalance and impeller mass imbalance are included, respectively, and a rotational speed power spectrum, a rotational speed amplitude frequency spectrum, a frequency spectrum of a forward and backward vibration amplitude of a nacelle, a frequency spectrum of a lateral vibration amplitude of the nacelle, and a rotational speed time sequence are respectively represented from top to bottom in each condition. The frequency spectrum graph is marked with the frequency and the amplitude of each channel signal under the condition of one time of rotation frequency of the impeller, the frequency and the amplitude of the channel signal under the condition of two times of rotation frequency of the impeller, and the frequency and the amplitude of the channel signal under the condition of three times of rotation frequency of the impeller.

In view of the above, according to the result of the trial and error test, the invention adopts a mode that the amplitude characteristics of the front and rear vibration signals of the nacelle are taken as the main and the amplitude characteristics of the rotating speed and the lateral vibration of the nacelle are taken as the auxiliary to carry out early warning on the aerodynamic imbalance fault of the impeller.

By extracting the amplitude values of the vibration signals of the front and the back of the engine room related to all the characteristic vectors in the characteristic vector group, if the amplitude values of the vibration signals of the front and the back of the K1 engine rooms are not smaller than a first preset threshold value, the pneumatic unbalance detection of the impeller of the wind turbine generator is executed, and the corresponding rotating speed amplitude value and the lateral vibration amplitude value of the engine room are combined to comprehensively determine the pneumatic unbalance detection result.

The first preset threshold value can be determined according to the model of the wind turbine generator, and can also be adjusted according to the requirement of detection precision.

And executing mass unbalance detection and outputting a mass unbalance detection result under the condition that the amplitude values of the continuous K2 machine cabin lateral vibration signals are not smaller than a second preset threshold value according to the characteristic vector group.

In combination with the analysis of fig. 3-5, the invention adopts a mode of mainly using the amplitude characteristic of the lateral vibration signal of the nacelle and secondarily using the amplitude characteristic of the rotating speed and the front and back vibration of the nacelle to carry out early warning on the mass unbalance fault of the impeller.

By extracting all cabin lateral vibration signal amplitudes related to the characteristic vectors in the characteristic vector group, if the detected continuous K2 cabin lateral vibration signal amplitudes are not smaller than a third preset threshold value, executing mass unbalance detection on the wind turbine generator impeller, and comprehensively determining a mass unbalance detection result by combining the corresponding rotating speed amplitude and the cabin front and back vibration amplitude.

The third preset threshold value can also be determined according to the model of the wind turbine generator, and can also be adjusted according to the requirement of detection precision. The first preset threshold may be the same as or different from the third preset threshold.

Where K1 and K2 may be the same or different, and are generally set to 3 or more from the viewpoint of detection accuracy.

The method for detecting the imbalance of the impeller of the wind turbine generator combines the early warning logics of longitudinal trend analysis and transverse multi-channel fusion, adopts pneumatic imbalance detection mainly based on front and back vibration of a cabin, adopts mass imbalance detection mainly based on lateral vibration of the cabin and is supplemented with other associated channels with lower sensitivity, compared with single-channel detection, the method is more comprehensive, and simultaneously combines the longitudinal trend analysis of multiple groups of running data in a time domain range, so that the phenomenon of misjudgment of local abnormal points can be effectively reduced, and the imbalance detection precision is improved.

Based on the disclosure of the above embodiments, as an alternative embodiment, the operation data includes at least one of a main shaft rotation speed or a generator rotation speed, a nacelle fore-aft vibration acceleration, and a nacelle lateral vibration acceleration;

the obtaining of the first-order rotation frequency characteristic vector of the impeller corresponding to the operating data in each acquisition period specifically includes:

acquiring a rotating speed power spectrum sequence pair according to the power spectrum density transformation of the rotating speed of the main shaft or the rotating speed of the generator in each acquisition period;

Firstly, a rotation speed sensor and a vibration sensor are installed at each corresponding position of a wind turbine generator, and a main shaft rotation speed omega _ rotor, a generator rotation speed omega _ gen, a front-back vibration acceleration a _ fa of a cabin and a lateral vibration acceleration a _ ss of the cabin of the wind turbine generator in each acquisition time period are acquired. The main shaft rotation speed omega _ rotor and the generator rotation speed omega _ gen can be collected selectively. In order to reduce the data processing amount, the sampling rate of each data may be set to 50Hz, and the sampling duration in each acquisition period may be set to 10min.

Further, power spectral density conversion and fast Fourier transform are respectively carried out on the collected generator rotating speed omega _ gen to obtain a rotating speed power spectrum sequence pair [ f _ omega _ gen _ psd, A _ omega _ gen _ psd ] and a rotating speed amplitude spectrum sequence pair [ f _ omega _ gen _ fft, A _ omega _ gen _ fft ]; and performing fast Fourier transform on the acquired front and rear vibration acceleration and lateral vibration acceleration of the cabin to obtain a front and rear vibration amplitude spectrum sequence pair [ f _ a _ fa _ fft, A _ a _ fa _ fft ] of the cabin and a lateral vibration amplitude spectrum sequence pair [ f _ a _ ss _ fft, A _ a _ ss _ fft ] of the cabin. A in the above sequence pair represents amplitude and f represents frequency.

Further, a secondary search method may be adopted to capture a first-order rotation frequency characteristic of the impeller from the rotation speed power spectrum sequence pair [ f _ ω _ gen _ psd, a _ ω _ gen _ psd ], the cabin forward and backward vibration amplitude spectrum sequence pair [ f _ a _ fa _ fft, a _ fa _ fft ] and the cabin lateral vibration amplitude spectrum sequence pair [ f _ a _ ss _ fft, a _ ss _ fft ], respectively, so that the amplitude of the cabin forward and backward vibration signal, the amplitude of the rotation speed signal and the amplitude of the cabin lateral vibration signal at one time of the rotation frequency of the corresponding impeller may be obtained. And finally, constructing the first-order frequency conversion characteristic vector of the impeller corresponding to the acquisition time period by the three amplitude values.

According to the method for detecting the imbalance of the impeller of the wind turbine generator, provided by the invention, the amplitude characteristics are searched in the horizontal direction from the rotating speed, the axial vibration of the engine room and the horizontal vibration of the engine room in a common mode, so that the multi-channel amplitude characteristic extraction is realized; meanwhile, amplitude characteristics of the running data in a plurality of continuous acquisition periods are mined in the longitudinal direction, so that the amplitude characteristics of the rotating speed and the vibration signal for realizing the detection of the unbalance of the impeller are more comprehensive.

Based on the content of the foregoing embodiment, as an optional embodiment, the determining the first-order rotation frequency eigenvector of the impeller corresponding to each acquisition period from the pair of the rotation speed power spectrum sequences, the pair of the frequency spectrum sequences of the forward and backward vibration amplitudes of the nacelle, and the pair of the frequency spectrum sequences of the lateral vibration amplitudes of the nacelle respectively specifically includes:

calculating the initial frequency under the one-time rotation frequency of the impeller according to the rotation speed of the main shaft or the rotation speed of the generator in each acquisition time period;

the first narrowband range is determined from the initial frequency, the second narrowband range is determined from the reference frequency, and the first narrowband range is greater than the second narrowband range.

For operation data in any acquisition time period, the method adopts a secondary search method to capture a first-order rotating frequency characteristic, namely a 1p amplitude value, of an impeller from a rotating speed power spectrum sequence pair, a cabin front and back vibration amplitude spectrum sequence pair and a cabin lateral vibration amplitude spectrum sequence pair, and mainly comprises the following steps:

(1) Converting the initial frequency f of the impeller under one-time rotation frequency according to the rotation speed of the main shaft or the generator _{1p_initial} The calculation formula may be:

wherein, f _{1p_initial} Representing an initial frequency; ω _ rotor represents the spindle speed; ω _ gen represents generator speed; the SpeedRatio represents the transmission ratio of a speed increaser of the wind turbine generator; mean represents the geometric mean, in rpm, of ω _ rotor and ω _ gen.

(2) Detecting initial frequency f from a rotating speed power spectrum sequence pair, a rotating speed amplitude frequency spectrum sequence pair, a cabin front and back vibration amplitude frequency spectrum sequence pair and a cabin lateral vibration amplitude frequency spectrum sequence pair by a peak picking method respectively _{1p_initial} A first amplitude maximum value in a nearby first narrow band range (deviation +/-band 1 bandwidth), and taking the frequency corresponding to the first amplitude maximum value as the frequency reference value of the corresponding channel, respectively recording as f _{1p_ref_ω_gen_psd} 、f _{1p_ref_ω_gen_fft} 、f _{1p_ref_a_fa_fft} And f _{1p_ref_a_ss_fft} 。

(3) Taking the median of the frequency reference values obtained by each channel as the reference frequency under the condition that the impeller has one time of rotation frequency:

f _{1p_update} ＝median([f _{1p_ref_ω_gen_psd} ，f _{1p_ref_ω_gen_fft} ，f _{1p_ref_a_fa_fft} ，f _{1p_ref_a_ss_fft} ])；

(4) Detecting the reference frequency f from the rotating speed power spectrum sequence pair, the cabin front and back vibration amplitude frequency spectrum sequence pair and the cabin lateral vibration amplitude frequency spectrum sequence pair by a peak picking method respectively _{1p_update} And taking the frequency and amplitude corresponding to the second amplitude maximum as the frequency and amplitude of the corresponding channel at one time of the rotation frequency of the impeller, wherein the frequency and amplitude are the second amplitude maximum in the second adjacent narrow-band range (deviation +/-band 2 bandwidth).

It should be noted that, in the present invention, the values of band1 and band2 may be 10% and 5%, respectively.

In the above steps (1) to (4), the process of constructing the first-order frequency conversion eigenvector of the impeller with respect to the operation data in the single acquisition period is described, and if the imbalance detection of the impeller is directly performed according to the single eigenvector, the misjudgment may be caused by the abnormality of the acquired operation data. Therefore, the method repeatedly executes the steps (1) to (4) by monitoring the operation data in a plurality of continuous acquisition time periods within a period of time to acquire the amplitude trend of the impeller with one-time rotation frequency of the rotating speed and the vibration signal.

The method for detecting the imbalance of the impeller of the wind turbine generator set provided by the invention adopts a secondary search method, combines the rotating speed and the vibration signal to further optimize the frequency band range of the impeller under one-time rotating frequency, and further searches the amplitude of each channel on the basis, so that the characteristic detection is more reliable.

In addition, due to the difference of vibration strength under different rotating speed conditions, the amplitude of the impeller at one time of rotation frequency under the same rotating speed condition is used as input, pneumatic unbalance faults and grades are preferentially judged, and when the pneumatic unbalance faults do not exist, mass unbalance faults and grades are judged.

Specifically, considering the complexity of the actual operating conditions, and in order to avoid misjudgment caused by the abnormality of a single operating data, the method provided by the invention performs pneumatic imbalance and mass imbalance fault judgment through the amplitude of a plurality of groups of continuous impellers under one-time rotating frequency at the same rotating speed, and specifically comprises the following steps:

(5) According to the feature vector group, determining a pneumatic unbalance detection result based on a comparison result of amplitude values of front and rear vibration signals of continuous K1 cabins and a first preset threshold, specifically comprising:

under the condition that the amplitudes of the front and rear vibration signals of the continuous K1 engine rooms are not smaller than a first preset threshold value, if the amplitudes of the front and rear vibration signals of the continuous K1 engine rooms are smaller than a third preset threshold value and the amplitudes of the continuous K1 rotating speed signals are not smaller than a fourth preset threshold value, outputting the pneumatic unbalance detection result as a conventional pneumatic unbalance fault;

Fig. 6 is a schematic flow chart of the pneumatic imbalance detection provided by the present invention, and as shown in fig. 6, when the amplitudes of the front and rear vibration signals of the continuous K1 group of data are not less than the first preset threshold T1 at the same rotation speed, the logical judgment of the pneumatic imbalance is started, otherwise, the pneumatic imbalance fault is considered to be absent.

When the pneumatic unbalance is judged, when the amplitude of the front and rear vibration signals of the continuous K1 group of data is not less than a third preset threshold value T2 at the same rotating speed, a serious pneumatic unbalance fault is considered to exist, otherwise, when the amplitude of the rotating speed signals of the continuous K1 group of data is not less than a fourth preset threshold value T3 at the same rotating speed or the amplitude of the lateral vibration signals of the engine room of the continuous K1 group of data is not less than a fifth preset threshold value T4 at the same rotating speed, a general pneumatic unbalance fault is considered to exist, and otherwise, the pneumatic unbalance fault is considered to not exist.

(6) Determining a mass unbalance detection result based on a comparison result of the amplitude values of the continuous K2 nacelle lateral vibration signals and a second preset threshold according to the feature vector group, wherein the mass unbalance detection result specifically comprises the following steps:

Fig. 7 is a schematic flow chart of the mass unbalance detection provided by the present invention, and as shown in fig. 7, when the amplitude of the lateral vibration signal of the continuous K2 group of data is not less than the second preset threshold B1 at the same rotation speed, the mass unbalance logic determination is started, otherwise, the mass unbalance fault is considered to be absent.

When mass unbalance fault is judged, when the amplitude of lateral vibration signals of the engine room of continuous K2 group data at the same rotating speed is not less than a sixth preset threshold value B2, serious mass unbalance fault is considered to exist, otherwise, when the amplitude of the rotating speed signals of the continuous K2 group data at the same rotating speed is not less than a seventh preset threshold value B3 and the amplitude of front and back vibration signals of the engine room of the continuous K2 group data at the same rotating speed is not greater than an eighth preset threshold value B4, general mass unbalance fault is considered to exist, and otherwise, mass unbalance fault is considered to not exist.

Fig. 8 is a schematic diagram of an amplitude trend under the impeller balance provided by the present invention, fig. 9 is a schematic diagram of an amplitude trend under the impeller aerodynamic imbalance provided by the present invention, fig. 10 is a schematic diagram of an amplitude trend under the impeller mass imbalance provided by the present invention, and with reference to fig. 8, fig. 9 and fig. 10, K1= K2=3 is set, and a threshold value for determining the aerodynamic imbalance under a rated rotation speed condition (average rotation speed fluctuation range 1700 ± 30 rpm) is set as: a first preset threshold T1=40, a third preset threshold T2=80, a fourth preset threshold T3= -0.9, a fifth preset threshold T4=19.7; the threshold for mass imbalance determination is set as: second preset threshold B1=30, sixth preset threshold B2=120, seventh preset threshold B3= -5, eighth preset threshold B4=25.0.

In the actual detection process, the preset thresholds T1, T2, T3, T4, B1, B2, B3 and B4 for judging the pneumatic imbalance and mass imbalance faults are all related to machine types, namely the same rotating speed working condition for logic judgment is determined according to the actual fan operation and data acquisition conditions, and the grid-connected rotating speed working condition with more data volume is preferentially adopted in the invention.

According to the method for detecting the imbalance of the impeller of the wind turbine generator, the corresponding threshold value can be set according to the combination of the actual data of the site and the engineering experience, so that the grades of the pneumatic imbalance fault and the gravity imbalance fault can be qualitatively given.

Based on the content of the foregoing embodiment, as an optional embodiment, the operation data in the multiple continuous acquisition periods are acquired under the same rotation speed condition;

the equal rotating speed condition means that the average rotating speed deviation of the wind turbine generator is smaller than a ninth preset threshold value in any two acquisition time periods.

The method adopts the amplitude of the impeller under one-time rotation frequency under the condition of the same rotation speed as input, preferentially judges the pneumatic unbalance fault and grade, and judges the mass unbalance fault and grade when the pneumatic unbalance fault does not exist.

Because the difference of the vibration intensity is large under different rotating speed conditions, when the trend early warning is carried out, the working condition data of the grid-connected rotating speed or the rated rotating speed is adopted, namely the working condition data of the fluctuation of the rotating speed of the generator within 30rpm of the deviation of the grid-connected rotating speed or the rated rotating speed (namely the ninth preset threshold is set to be 30 rpm), and the working condition data between the grid-connected rotating speed and the rated rotating speed and outside the resonance crossing area can be selected as the alternative scheme.

Fig. 11 is a schematic structural diagram of the wind turbine impeller imbalance detection device provided in the present invention, as shown in fig. 11, the wind turbine impeller imbalance detection device mainly includes: data acquisition unit 101, data processing unit 102 and unbalance detection unit 103, wherein:

the data acquisition unit 101 is mainly used for acquiring the operating data of the wind turbine generator in a plurality of continuous acquisition time periods; the data processing unit 102 is mainly configured to obtain a first-order rotation frequency eigenvector of the impeller corresponding to the operating data in each acquisition period, so as to construct an eigenvector group; the unbalance detection unit 103 is mainly used for

It should be noted that, when the device for detecting imbalance of an impeller of a wind turbine generator provided in the embodiment of the present invention is in specific operation, the method for detecting imbalance of an impeller of a wind turbine generator described in any of the above embodiments may be executed, and details of this embodiment are not described herein.

The wind turbine impeller imbalance detection device provided by the invention combines the early warning logics of longitudinal trend analysis and transverse multi-channel fusion, adopts pneumatic imbalance detection mainly based on front and back vibration of the engine room, adopts mass imbalance detection mainly based on lateral vibration of the engine room, is assisted by other associated channels with lower sensitivity, is more comprehensive compared with single-channel detection, and simultaneously combines the longitudinal trend analysis of multiple groups of running data in a time domain range, so that the phenomenon of misjudgment of local abnormal points can be effectively reduced, and the imbalance detection precision is improved.

Fig. 12 is a schematic structural diagram of an electronic device provided in the present invention, and as shown in fig. 12, the electronic device may include: a processor (processor) 110, a communication Interface (communication Interface) 120, a memory (memory) 130 and a communication bus 140, wherein the processor 110, the communication Interface 120 and the memory 130 are communicated with each other via the communication bus 140. The processor 110 may invoke logic instructions in the memory 130 to perform a wind turbine blade imbalance detection method comprising: collecting operating data of the wind turbine generator in a plurality of continuous collecting time periods; acquiring a first-order frequency conversion eigenvector of the impeller corresponding to the operation data in each acquisition time period to construct an eigenvector group; acquiring a pneumatic unbalance detection result and/or a mass unbalance detection result according to the feature vector group; the pneumatic unbalance detection result is determined based on the comparison result of the amplitude of the front and rear vibration signals of the continuous K1 cabins and a first preset threshold; and the mass unbalance detection result is determined based on the comparison result of the amplitude values of the continuous K2 cabin lateral vibration signals and a second preset threshold value.

In addition, the logic instructions in the memory 130 may be implemented in the form of software functional units and stored in a computer readable storage medium when the logic instructions are sold or used as independent products. Based on such understanding, the technical solution of the present invention may be embodied in the form of a software product, which is stored in a storage medium and includes instructions for causing a computer device (which may be a personal computer, a server, or a network device) to execute all or part of the steps of the method according to the embodiments of the present invention. And the aforementioned storage medium includes: a U-disk, a removable hard disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk or an optical disk, and other various media capable of storing program codes.

In another aspect, the present invention also provides a computer program product comprising a computer program stored on a non-transitory computer readable storage medium, the computer program comprising program instructions which, when executed by a computer, enable the computer to perform the wind turbine blade imbalance detection method provided by the above methods, the method comprising: collecting operating data of the wind turbine generator in a plurality of continuous collecting time periods; acquiring a first-order frequency conversion eigenvector of the impeller corresponding to the operation data in each acquisition time period to construct an eigenvector group; acquiring a pneumatic unbalance detection result and/or a mass unbalance detection result according to the feature vector group; the pneumatic unbalance detection result is determined based on the comparison result of the amplitude of the front and rear vibration signals of the continuous K1 cabins and a first preset threshold; and the mass unbalance detection result is determined based on the comparison result of the amplitude values of the continuous K2 cabin lateral vibration signals and a second preset threshold value.

In yet another aspect, the present invention further provides a non-transitory computer-readable storage medium, on which a computer program is stored, the computer program being implemented by a processor to execute the wind turbine blade imbalance detection method provided in the foregoing embodiments, the method including:

collecting operating data of the wind turbine generator in a plurality of continuous collecting time periods; acquiring a first-order frequency conversion eigenvector of the impeller corresponding to the operation data in each acquisition time period to construct an eigenvector group; acquiring a pneumatic unbalance detection result and/or a mass unbalance detection result according to the feature vector group; the pneumatic unbalance detection result is determined based on the comparison result of the amplitude of the front and rear vibration signals of the continuous K1 cabins and a first preset threshold; and the mass unbalance detection result is determined based on the comparison result of the amplitude values of the continuous K2 cabin lateral vibration signals and a second preset threshold value.

The above-described embodiments of the apparatus are merely illustrative, and the units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of the present embodiment. One of ordinary skill in the art can understand and implement it without inventive effort.

Through the above description of the embodiments, those skilled in the art will clearly understand that each embodiment may be implemented by software plus a necessary general hardware platform, and may also be implemented by hardware. With this understanding in mind, the above-described technical solutions may be embodied in the form of a software product, which can be stored in a computer-readable storage medium such as ROM/RAM, magnetic disk, optical disk, etc., and includes instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute the methods described in the embodiments or some parts of the embodiments.

Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.

Claims

1. A wind turbine generator impeller imbalance detection method is characterized by comprising the following steps:

the mass unbalance detection result is determined based on the comparison result of the amplitude values of the continuous K2 cabin lateral vibration signals and a second preset threshold value;

the operation data comprises at least one of a main shaft rotating speed or a generator rotating speed, a cabin front-back vibration acceleration and a cabin lateral vibration acceleration;

respectively determining a first-order rotation frequency characteristic vector of the impeller corresponding to each acquisition time period from the rotating speed power spectrum sequence pair, the cabin front and back vibration amplitude spectrum sequence pair and the cabin lateral vibration amplitude spectrum sequence pair, and specifically comprising the following steps:

2. The method for detecting the imbalance of the impeller of the wind turbine generator set according to claim 1, wherein a calculation formula for calculating the initial frequency of the impeller at one time of the rotation frequency according to the rotation speed of the main shaft or the rotation speed of the generator in each acquisition period is as follows:

wherein, f _{1p_initial} Representing an initial frequency; ω _ rotor represents the spindle speed; ω _ gen represents generator speed; the SpeedRatio represents the transmission ratio of a speed increaser of the wind turbine generator; mean represents the geometric mean.

3. The wind turbine generator impeller imbalance detection method according to claim 1, wherein the pneumatic imbalance detection result is determined based on a comparison result of amplitude values of front and rear vibration signals of the continuous K1 nacelles and a first preset threshold, and specifically comprises:

under the condition that the amplitudes of the front and rear vibration signals of the continuous K1 engine rooms are not smaller than a first preset threshold value, if the amplitudes of the front and rear vibration signals of the continuous K1 engine rooms are not smaller than a third preset threshold value, outputting the pneumatic unbalance detection result as a serious pneumatic unbalance fault, wherein the third preset threshold value is larger than the first preset threshold value;

under the condition that the amplitudes of the front and rear vibration signals of the continuous K1 engine rooms are not smaller than a first preset threshold value, if the amplitudes of the front and rear vibration signals of the continuous K1 engine rooms are smaller than a third preset threshold value and the amplitudes of the continuous K1 rotating speed signals are not smaller than the third preset threshold value, outputting the pneumatic unbalance detection result as a conventional pneumatic unbalance fault;

under the condition that the amplitudes of the front and rear vibration signals of the continuous K1 engine rooms are not smaller than a first preset threshold value, if the amplitudes of the front and rear vibration signals of the continuous K1 engine rooms are smaller than a third preset threshold value, the amplitudes of the continuous K1 rotation speed signals are smaller than a third preset threshold value, and the amplitudes of the lateral vibration signals of the continuous K1 engine rooms are smaller than a fifth preset threshold value, outputting the detection result of the pneumatic unbalance to be normal;

4. The wind turbine generator impeller imbalance detection method according to claim 1, wherein the mass imbalance detection result is determined based on a comparison result of the amplitudes of the continuous K2 nacelle lateral vibration signals and a second preset threshold, and specifically comprises:

under the condition that the amplitudes of the front and rear vibration signals of the continuous K2 engine rooms are not smaller than a second preset threshold value, if the amplitudes of the lateral vibration signals of the continuous K2 engine rooms are smaller than a sixth preset threshold value, the amplitudes of the continuous K2 rotating speed signals are not smaller than a seventh preset threshold value, and the amplitudes of the front and rear vibration signals of the continuous K2 engine rooms are larger than an eighth preset threshold value, outputting a mass unbalance detection result to be normal;

5. The method for detecting the imbalance of the impeller of the wind turbine generator set according to claim 1, wherein the operation data in the plurality of continuous acquisition time periods are acquired under the condition of the same rotating speed;

6. The utility model provides a wind turbine generator system impeller unbalance detection device which characterized in that includes:

the unbalance detection unit is used for acquiring a pneumatic unbalance detection result and/or a mass unbalance detection result according to the feature vector group;

wherein the operational data comprises at least one of a main shaft rotation speed or a generator rotation speed, a nacelle fore-aft vibration acceleration and a nacelle lateral vibration acceleration;

7. An electronic device comprising a memory, a processor and a computer program stored on the memory and executable on the processor, wherein the processor implements the wind turbine blade imbalance detection method steps according to any one of claims 1 to 5 when executing the computer program.

8. A non-transitory computer-readable storage medium, on which a computer program is stored, which, when being executed by a processor, carries out the wind turbine blade imbalance detection method steps of any one of claims 1 to 5.