CN111173687B - On-line monitoring device and method for crack damage of wind power fan blade - Google Patents
On-line monitoring device and method for crack damage of wind power fan blade Download PDFInfo
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- CN111173687B CN111173687B CN201911390310.8A CN201911390310A CN111173687B CN 111173687 B CN111173687 B CN 111173687B CN 201911390310 A CN201911390310 A CN 201911390310A CN 111173687 B CN111173687 B CN 111173687B
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F03—MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
- F03D—WIND MOTORS
- F03D17/00—Monitoring or testing of wind motors, e.g. diagnostics
Abstract
The invention discloses an online monitoring device and method for crack damage of a wind power fan blade, wherein the device comprises the following steps: the data acquisition device is arranged on the wind power fan blade and is used for acquiring the acceleration values of the blade in X, Y, Z three directions; the wireless signal receiving module is used for receiving the data acquired by the data acquisition device and sending the data to the data processing module; the data processing module is used for processing the acquired data and judging whether the blade has crack damage or not; the master control system receives the blade damage judgment result and sends a blade damage alarm signal; and controlling the blades of the wind power fan. According to the method, the step ratio analysis is adopted, sampling is carried out by adopting different sampling frequencies according to different rotating speeds of the fan blades, the obtained vibration waveforms of the fan blades can be compared more accurately, and the online monitoring of the crack damage of the wind power fan blades is realized.
Description
Technical Field
The invention relates to an online monitoring device and method for crack damage of a wind power fan blade, and belongs to the technical field of power generation systems.
Background
The domestic wind power generation is developed in a leap-forward manner within 15 years, along with the rapid promotion of localization and high power of a wind power generation unit, the equipment failure rate of the wind power generation unit is high, serious accidents such as wind power tower falling, fire, runaway and the like occur endlessly, a batch of serious wind power accidents need to be reported by the national energy bureau every year, and the number of wind power accident claim cases in 2012 and 2016 is counted and 1526.
The blade is one of the most critical parts of the wind generating set, bears the comprehensive actions of centrifugal force, fluid power, vibration, temperature difference, medium and the like, and the safe operation of the blade is directly related to the safety of the whole wind generating set. Generally, the surface of the blade of the wind generating set is cracked after the wind generating set operates for two to three years. The cracks can be deepened and lengthened by each self-vibration and parking of the wind generating set, and dirt and sand in the air can also run in a false mode while the cracks are expanded, so that the cracks are deepened and widened. The propagation of cracks can lead to blade breakage and seriously threaten the safety of the blade. Therefore, monitoring of blade cracking conditions is very important.
The existing blade crack diagnosis method can only diagnose whether the blade has cracks or not and cannot specifically detect the positions of the cracks by means of carrying out frequency spectrum analysis on the obtained vibration signals based on an acoustic emission technology, so that economic loss caused by the cracks of the blade cannot be effectively avoided, and the difficulty of equipment maintenance is increased.
Disclosure of Invention
Aiming at the defects of the method, the invention provides an online monitoring device and method for crack damage of a wind power fan blade, which can be used for monitoring the crack damage of the wind power fan blade
The technical scheme adopted for solving the technical problems is as follows:
on one hand, the online monitoring device for the crack damage of the wind power fan blade provided by the embodiment of the invention comprises:
the data acquisition device is arranged on the wind power fan blade and is used for acquiring the acceleration values of the blade in X, Y, Z three directions;
the wireless signal receiving module is used for receiving the data acquired by the data acquisition device and sending the data to the data processing module;
the data processing module is used for processing the acquired data and judging whether the blade has crack damage or not;
the master control system receives the blade damage judgment result and sends a blade damage alarm signal; and controlling the blades of the wind power fan.
As a possible implementation manner of this embodiment, the data acquisition device includes a triaxial acceleration sensor, a charge amplification module, an a/D conversion module, and a wireless transmission module, acceleration values of the triaxial acceleration sensor blade in X, Y, Z three directions are processed by the charge amplification module and the a/D conversion module, and then are sent to the wireless signal receiving module through the wireless transmission module.
As a possible implementation manner of this embodiment, the three-axis acceleration sensor is an MEMS three-axis acceleration sensor, the MEMS three-axis acceleration sensor is installed inside a blade of the wind turbine, an X axis is parallel to a direction of a pointed tip of the blade, and a Z axis is perpendicular to the blade.
As a possible implementation manner of this embodiment, the data processing module includes a filtering and denoising module, a database, and a signal comparison module, and the filtering and denoising module performs filtering and denoising processing on the acquired blade data; the database stores blade data of the wind power fan; and the signal comparison module is used for comparing the processed blade data and judging whether the blade has crack damage or not.
As a possible implementation manner of this embodiment, the data processing module further includes a rotation speed calculating module, and the rotation speed calculating module calculates the rotation speed of the blade according to the acceleration value of the blade in the Z direction.
On the other hand, the online monitoring method for the crack damage of the wind power fan blade provided by the embodiment of the invention comprises the following steps:
collecting acceleration values of the fan blade X, Y, Z in three directions;
analyzing and processing the acceleration value of the fan blade;
calculating the rotating speed of the blade according to the acceleration value of the fan blade in the X direction;
adjusting sampling frequency according to the rotating speed of the fan;
sampling and analyzing the acceleration value in the Z direction by adopting a step ratio sampling method to obtain waveform data of the Z axis;
carrying out filtering and denoising processing on the waveform data of the Z axis, and carrying out fast Fourier transform on the time domain vibration signal after the filtering processing to convert the time domain vibration signal into a frequency domain signal;
judging whether the blade has crack damage or not according to the processed Z-axis waveform data;
and when the blade is damaged, alarming.
As a possible implementation manner of this embodiment, the process of determining whether the blade has the crack damage according to the processed Z-axis waveform data includes:
the method comprises the steps of obtaining vibration waveforms of three blades through a step ratio sampling method, placing the vibration waveforms of the three fan blades in the same time period in the same graph for comparison, and judging that the fan blades are damaged when the similarity of the vibration waveforms of the three blades is lower than a threshold value.
As a possible implementation manner of this embodiment, the process of determining whether the blade has the crack damage according to the processed Z-axis waveform data includes:
the acquired waveform data and the fan rotation speed are placed in the same time domain graph for comparison, the relation between the amplitude of the vibration waveform and the fan rotation speed is observed, and when the amplitude and the rotation speed are in a gentle positive correlation, the fan blade is not damaged; and when the non-positive correlation or the sharply changed positive correlation is formed and the whole numerical value is increased, judging that the fan blade is damaged.
As a possible implementation manner of this embodiment, in the process of acquiring acceleration values of the fan blade X, Y, Z in three directions, the MEMS three-axis acceleration sensor is installed inside the wind turbine blade, the X axis is parallel to the direction of the pointed blade tip of the blade, and the Z axis is perpendicular to the blade.
As a possible implementation manner of this embodiment, the process of calculating the rotation speed of the blade according to the acceleration value of the fan blade in the X direction and the number of rotations of the blade is as follows:
recording an acceleration value of an X axis of a blade pointing to the blade tip direction measured by a triaxial acceleration sensor;
when the blade rotates from the highest point to the lowest point and then rotates to the highest point, the process is repeated for one circle, and the average time of the cycle for one circle is recorded, namely the rotation period of the blade;
and calculating the rotating speed of the blade according to the acceleration value of the fan blade in the X direction.
The technical scheme of the embodiment of the invention has the following beneficial effects:
according to the technical scheme of the embodiment of the invention, order ratio analysis is adopted, sampling is carried out by adopting different sampling frequencies according to different rotating speeds of the fan blade, the obtained vibration waveforms of the fan blade can be compared more accurately, and the online monitoring of the crack damage of the wind power fan blade is realized.
According to the technical scheme of the embodiment of the invention, the vibration waveform of the fan blade is sampled according to the rotating speed of the fan, the obtained waveform diagram is more accurate, and whether the blade has crack damage or not is judged according to the waveform data of the Z axis by comparing the time domain diagram and the vibration waveform coincidence rate of the three blades, so that the accuracy of on-line monitoring of the crack damage of the wind power fan blade is ensured.
Description of the drawings:
FIG. 1 is a block diagram illustrating an online crack damage monitoring device for a wind turbine blade according to an exemplary embodiment;
FIG. 2 is a flow chart illustrating a method for online monitoring of crack damage to a wind turbine blade according to an exemplary embodiment.
Detailed Description
The invention is further illustrated by the following examples in conjunction with the accompanying drawings:
in order to clearly explain the technical features of the present invention, the following detailed description of the present invention is provided with reference to the accompanying drawings. The following disclosure provides many different embodiments, or examples, for implementing different features of the invention. To simplify the disclosure of the present invention, the components and arrangements of specific examples are described below. Furthermore, the present invention may repeat reference numerals and/or letters in the various examples. This repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and/or configurations discussed. It should be noted that the components illustrated in the figures are not necessarily drawn to scale. Descriptions of well-known components and processing techniques and procedures are omitted so as to not unnecessarily limit the invention.
FIG. 1 is a structural diagram of an online crack damage monitoring device for a wind turbine blade according to an exemplary embodiment. As shown in fig. 1, an online monitoring device for crack damage of a wind turbine blade according to an embodiment of the present invention includes:
the data acquisition device is arranged on the wind power fan blade and is used for acquiring the acceleration values of the blade in X, Y, Z three directions;
the wireless signal receiving module is used for receiving the data acquired by the data acquisition device and sending the data to the data processing module;
the data processing module is used for processing the acquired data and judging whether the blade has crack damage or not;
the master control system receives the blade damage judgment result and sends a blade damage alarm signal; and controlling the blades of the wind power fan.
As a possible implementation manner of this embodiment, the data acquisition device includes a triaxial acceleration sensor, a charge amplification module, an a/D conversion module, and a wireless transmission module, acceleration values of the triaxial acceleration sensor blade in X, Y, Z three directions are processed by the charge amplification module and the a/D conversion module, and then are sent to the wireless signal receiving module through the wireless transmission module.
As a possible implementation manner of this embodiment, the three-axis acceleration sensor is an MEMS three-axis acceleration sensor, the MEMS three-axis acceleration sensor is installed inside a blade of the wind turbine, an X axis is parallel to a direction of a pointed tip of the blade, and a Z axis is perpendicular to the blade.
As a possible implementation manner of this embodiment, the data processing module includes a filtering and denoising module, a database, and a signal comparison module, and the filtering and denoising module performs filtering and denoising processing on the acquired blade data; the database stores blade data of the wind power fan; and the signal comparison module is used for comparing the processed blade data and judging whether the blade has crack damage or not.
As a possible implementation manner of this embodiment, the data processing module further includes a rotation speed calculating module, and the rotation speed calculating module calculates the rotation speed of the blade according to the acceleration value of the blade in the Z direction.
FIG. 2 is a flow chart illustrating a method for online monitoring of crack damage to a wind turbine blade according to an exemplary embodiment. As shown in fig. 2, the online monitoring method for crack damage of the wind turbine blade provided by the embodiment of the invention includes the following steps:
collecting acceleration values of the fan blade X, Y, Z in three directions;
analyzing and processing the acceleration value of the fan blade;
calculating the rotating speed of the blade according to the acceleration value of the fan blade in the X direction;
adjusting sampling frequency according to the rotating speed of the fan;
sampling and analyzing the acceleration value in the Z direction by adopting a step ratio sampling method to obtain waveform data of the Z axis;
carrying out filtering and denoising processing on the waveform data of the Z axis, and carrying out fast Fourier transform on the time domain vibration signal after the filtering processing to convert the time domain vibration signal into a frequency domain signal;
judging whether the blade has crack damage or not according to the processed Z-axis waveform data;
and when the blade is damaged, alarming.
As a possible implementation manner of this embodiment, the process of determining whether the blade has the crack damage according to the processed Z-axis waveform data includes:
the acquired waveform data and the fan rotation speed are placed in the same time domain graph for comparison, the relation between the amplitude of the vibration waveform and the fan rotation speed is observed, and when the amplitude and the rotation speed are in a gentle positive correlation, the fan blade is not damaged; and when the non-positive correlation or the sharply changed positive correlation is formed and the whole numerical value is increased, judging that the fan blade is damaged.
In the implementation mode, the specific process of online monitoring of the crack damage of the blade of the wind power fan comprises the following steps:
s1: an MEMS triaxial acceleration sensor is installed in the fan blade in an inner side mode in such a way that an X axis is parallel to the blade pointing to the blade tip, and a Z axis is perpendicular to the blade.
And S2, acquiring acceleration values of the fan blade X, Y, Z in three directions by the MEMS triaxial acceleration sensor, and transmitting signals to the wireless signal receiving module through the wireless transmitting module.
And S3, the signal processing module analyzes and processes the received acceleration value. The value measured by the sensor in the X-axis direction can regularly change according to the rotation of the blade for one circle, the measured value is the minimum when the blade rotates to the highest point, the measured value is the maximum when the blade rotates to the lowest point, and the process is repeated once and is a circle. At this time, the counter of the signal processing module is increased by one. The rotational speed of the fan blade can be calculated.
S4: the rotating speed of the fan is sent to the blade sensor module through the wireless signal module, and the MEMS sensor adjusts sampling frequency according to the rotating speed of the fan. And sampling and analyzing the Z axis of the sensor by adopting a step ratio sampling method to obtain the waveform data of the Z axis of the MEMS sensor. And transmitting the signal to the wireless signal receiving module through the wireless transmitting module.
And S5, the data processing module filters and denoises the information from the wireless signal receiving module.
And S6, comparing the acquired spectrogram with the fan rotating speed in the same graph, and observing the relation between the spectrogram and the fan rotating speed. When the positive correlation is gentle, the fan blade is not damaged; and when the non-positive correlation or the sharply changed positive correlation is formed but the whole numerical value is increased, judging that the fan blade is damaged.
And S7, when the blade is damaged, transmitting an alarm signal to background personnel through the optical fiber connected with the equipment.
And comparing the obtained vibration oscillogram with the rotating speed of the fan, and continuously taking the rotating speed for N times in a certain time period. The higher the principle rotation speed, the larger the amplitude of the vibration waveform and the gentle positive correlation. Therefore, if the amplitude and the rotating speed are in a non-positive correlation or a rapidly-changing positive correlation and the overall numerical value is increased, the damage of the fan blade is judged.
As a possible implementation manner of this embodiment, the process of determining whether the blade has the crack damage according to the processed Z-axis waveform data includes:
the vibration waveforms of the three blades are obtained through a step ratio sampling method, the vibration waveforms of the three blades are placed in the same image for comparison, and when the similarity of the vibration waveforms of the three blades is lower than a threshold value, the blades of the fan are considered to be damaged.
In the implementation mode, the specific process of online monitoring of the crack damage of the blade of the wind power fan is as follows.
S1: an MEMS triaxial acceleration sensor is installed in the fan blade in an inner side mode in such a way that an X axis is parallel to the blade pointing to the blade tip, and a Z axis is perpendicular to the blade.
And S2, acquiring acceleration values of the fan blade X, Y, Z in three directions by the MEMS triaxial acceleration sensor, and transmitting signals to the wireless signal receiving module through the wireless transmitting module.
And S3, the signal processing module analyzes and processes the received acceleration value. The value measured by the sensor in the X-axis direction can regularly change according to the rotation of the blade for one circle, the measured value is the minimum when the blade rotates to the highest point, the measured value is the maximum when the blade rotates to the lowest point, and the process is repeated once and is a circle. At this time, the counter of the signal processing module is increased by one. The rotational speed of the fan blade can be calculated.
S4: the rotating speed of the fan is sent to the blade sensor module through the wireless signal module, and the MEMS sensor adjusts sampling frequency according to the rotating speed of the fan. And sampling and analyzing the Z axis of the sensor by adopting a step ratio sampling method to obtain the waveform data of the Z axis of the MEMS sensor. And transmitting the signal to the wireless signal receiving module through the wireless transmitting module.
And S5, the data processing module filters and denoises the information from the wireless signal receiving module.
And S6, acquiring vibration waveforms of the three blades by a step ratio sampling method, comparing the vibration waveforms of the three blades in the same graph, and determining that the blades of the fan are damaged when the similarity of the vibration waveforms of the three blades is lower than a threshold value.
And S7, when the blade is damaged, transmitting an alarm signal to background personnel through the optical fiber connected with the equipment.
The vibration waveforms of the three blades are obtained according to a step ratio sampling method, and are put in the same graph for comparison, so that the vibration waveforms of the three blades are consistent in principle. The probability that three blades are damaged simultaneously is considered to be very low by the aid of the fan, so that the probability is ignored, and therefore when the similarity of vibration waveforms of the three blades is lower than a certain threshold value, the blades of the fan are considered to be damaged.
As a possible implementation manner of this embodiment, in the process of acquiring acceleration values of the fan blade X, Y, Z in three directions, the MEMS three-axis acceleration sensor is installed inside the wind turbine blade, the X axis is parallel to the direction of the pointed blade tip of the blade, and the Z axis is perpendicular to the blade.
As a possible implementation manner of this embodiment, the process of calculating the rotation speed of the blade according to the acceleration value of the fan blade in the X direction and the number of rotations of the blade is as follows:
recording an acceleration value of an X axis of a blade pointing to the blade tip direction measured by a triaxial acceleration sensor;
when the blade rotates from the highest point to the lowest point and then rotates to the highest point, the process is repeated for one circle, and the average time of the cycle for one circle is recorded, namely the rotation period of the blade;
and calculating the rotating speed of the blade according to the acceleration value of the fan blade in the X direction.
The foregoing is only a preferred embodiment of the present invention, and it will be apparent to those skilled in the art that various modifications and improvements can be made without departing from the principle of the present invention, and these modifications and improvements are also considered to be within the scope of the present invention.
Claims (1)
1. An online monitoring method for crack damage of a wind power fan blade is characterized by comprising the following steps:
the acceleration values of the fan blade X, Y, Z in three directions are collected: in the process of acquiring acceleration values of the fan blade X, Y, Z in three directions, the MEMS three-axis acceleration sensor is installed on the inner side of the wind power fan blade, the X axis is parallel to the direction of the blade tip, and the Z axis is perpendicular to the blade;
analyzing and processing the acceleration value of the fan blade;
calculating the rotating speed of the blade according to the acceleration value of the fan blade in the X direction;
adjusting sampling frequency according to the rotating speed of the fan blade;
sampling and analyzing the acceleration value in the Z direction by adopting a step ratio sampling method to obtain waveform data of the Z axis;
carrying out filtering and denoising processing on the waveform data of the Z axis;
judging whether the blade has crack damage according to the processed Z-axis waveform data: the acquired waveform data and the rotating speed of the fan blade are compared in the same graph, the relation between the amplitude of the vibration waveform and the rotating speed of the fan blade is observed, and when the amplitude and the rotating speed are in a gentle positive correlation, the fan blade is not damaged; when a non-positive correlation or a rapidly-changing positive correlation is formed and the overall numerical value is increased, judging that the fan blade is damaged;
and when the blade is damaged, alarming.
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| CN113958463A (en) * | 2021-10-12 | 2022-01-21 | 深圳前海慧联科技发展有限公司 | Online monitoring method, system and device for fan blade |
| TWI781850B (en) * | 2021-12-10 | 2022-10-21 | 國立勤益科技大學 | Intelligent networked wind power generation fault diagnosis and detection system and detection method |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN104914165A (en) * | 2015-05-06 | 2015-09-16 | 上海电机学院 | Wind-electricity draught fan blade crack damage online monitoring device and monitoring method thereof |
| CN107356384A (en) * | 2017-07-26 | 2017-11-17 | 安徽容知日新科技股份有限公司 | Method, computing device and the system of the state of blade in a kind of monitoring wind power plant |
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| US9194843B2 (en) * | 2013-03-15 | 2015-11-24 | Digital Wind Systems, Inc. | Method and apparatus for monitoring wind turbine blades during operation |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104914165A (en) * | 2015-05-06 | 2015-09-16 | 上海电机学院 | Wind-electricity draught fan blade crack damage online monitoring device and monitoring method thereof |
| CN107356384A (en) * | 2017-07-26 | 2017-11-17 | 安徽容知日新科技股份有限公司 | Method, computing device and the system of the state of blade in a kind of monitoring wind power plant |
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