CN114324607A - Insulator surface crack detection device and method based on ultrasonic guided wave energy - Google Patents
Insulator surface crack detection device and method based on ultrasonic guided wave energy Download PDFInfo
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- 238000012545 processing Methods 0.000 claims description 2
- 230000035945 sensitivity Effects 0.000 abstract description 3
- 238000003384 imaging method Methods 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
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- G01N29/00—Investigating or analysing materials by the use of ultrasonic, sonic or infrasonic waves; Visualisation of the interior of objects by transmitting ultrasonic or sonic waves through the object
- G01N29/04—Analysing solids
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N29/00—Investigating or analysing materials by the use of ultrasonic, sonic or infrasonic waves; Visualisation of the interior of objects by transmitting ultrasonic or sonic waves through the object
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- G01N29/041—Analysing solids on the surface of the material, e.g. using Lamb, Rayleigh or shear waves
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- G—PHYSICS
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- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
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Abstract
The invention discloses an insulator surface crack detection device and method based on ultrasonic guided wave energy, wherein the device comprises: an upper computer; the flaw detector is connected with the upper computer and is used for generating pulse signals; the ultrasonic detection unit is arranged on the surface of the insulator and is connected with the flaw detector; the invention improves the sensitivity of the ultrasonic guided wave in detecting the micro cracks and has stronger engineering application value.
Description
Technical Field
The invention relates to the technical field of insulator nondestructive testing, in particular to an insulator surface crack detection device and method based on ultrasonic guided wave energy.
Background
At present, Gas insulated Switchgear (GIS for short) has the advantages of high reliability, short installation period, long overhaul period and the like, so that the Gas insulated Switchgear is widely applied to transformer substations. As the most important insulating part in the GIS, the basin-type insulator plays the roles of electrical insulation, gas sealing, shell reinforcement and support. In actual production and live-line operation, due to the fact that factors such as improper control of a production process, uneven stress distribution of bolt fasteners at flanges, unbalanced stress of bus guide rods, opening and closing vibration of a circuit breaker and the like can cause deformation and cracking of the basin-type insulator, and further faults such as GIS (gas insulated switchgear) gas leakage, partial discharge and even insulator surface flashover are caused, and therefore large-area power failure accidents are caused. Therefore, the crack detection aiming at the basin-type insulator has great significance for the safe operation of the GIS
However, at present, the crack detection means for the basin-type insulator mainly comprises vibration method detection, X-DR imaging detection, laser ultrasonic detection and the like. The vibration method is used for judging whether a crack defect exists or not by observing the change rule of the modal frequency of the basin-type insulator in different states, but the establishment of a comprehensive and perfect diagnosis library is extremely difficult due to the diversity of insulator types and manufacturing formulas of different manufacturers. X-DR imaging can realize the visualization of crack detection, but the X-DR imaging has high cost and poor portability and is not suitable for field detection. The laser ultrasonic detection generates ultrasonic waves through the action of high-energy laser pulses and instantaneous heat on the surface of an insulator, and then ultrasonic signals are received by a piezoelectric transducer for analysis.
Therefore, how to provide an apparatus and a method for detecting cracks on the surface of an insulator, which can solve the above problems, is a problem that needs to be solved by those skilled in the art.
Disclosure of Invention
In view of the above, the invention provides an insulator surface crack detection device and method based on ultrasonic guided wave energy, and the method can realize crack detection of a basin-type insulator, improve the sensitivity of ultrasonic guided wave detection of tiny cracks, and have strong engineering application value.
In order to achieve the purpose, the invention adopts the following technical scheme:
the utility model provides an insulator surface crack detection device based on supersound guided wave energy, includes:
an upper computer;
the flaw detector is connected with the upper computer and is used for generating pulse signals;
the ultrasonic detection unit is arranged on the surface of the insulator and is connected with the flaw detector.
Preferably, the ultrasonic detection unit comprises a signal excitation end and a signal receiving end, and both the signal excitation end and the signal receiving end are connected with the flaw detector;
the signal excitation end is used for receiving the pulse signal and generating an ultrasonic signal, and the signal receiving end is used for receiving the ultrasonic signal and sending the ultrasonic signal to the upper computer through the flaw detector.
Preferably, the upper computer is configured to process the received ultrasonic signal to obtain a corresponding ultrasonic signal energy attenuation rate, so as to implement surface crack detection on the insulator.
Further, the invention also provides a detection method using any one of the above devices for detecting surface cracks of an insulator based on ultrasonic guided wave energy, which comprises the following steps:
the flaw detector generates a pulse signal;
the ultrasonic detection unit collects ultrasonic signals generated on the surface of the insulator and sends the ultrasonic signals to the upper computer;
and the upper computer processes the ultrasonic signals to obtain corresponding ultrasonic signal energy attenuation rate, so that the surface crack detection of the insulator is realized.
Preferably, the method further comprises the following steps: the specific process of collecting the ultrasonic signals generated on the surface of the insulator comprises the following steps:
the ultrasonic detection unit comprises a signal excitation end and a signal receiving end;
the signal excitation end receives the pulse signal and generates an ultrasonic signal, and the signal receiving end is used for receiving the ultrasonic signal and sending the ultrasonic signal to the upper computer through the flaw detector.
Preferably, the upper computer obtains the corresponding ultrasonic guided wave energy according to the ultrasonic signal, and further obtains the ultrasonic guided wave energy attenuation rate by taking the ultrasonic guided wave energy as a characteristic quantity.
Preferably, the specific expression of the ultrasonic signal energy attenuation rate is as follows:
in the formula, F0And F is the guided wave energy of the signal received by the sensor under the intact state and the crack state of the insulator respectively.
According to the technical scheme, compared with the prior art, the invention discloses and provides the insulator surface crack detection device and method based on ultrasonic guided wave energy, the upper computer is utilized to control the flaw detector to generate a unipolar pulse signal, the pulse signal is applied to the detection unit adhered to the surface of the insulator to generate ultrasonic guided waves, and the receiving end sensor sends an ultrasonic response signal with insulator state information to the upper computer through the flaw detector; and calculating ultrasonic guided wave energy based on the ultrasonic response signal, further calculating the ultrasonic guided wave energy attenuation rate by taking the ultrasonic detection signal of the intact basin-type insulator as a reference by taking the ultrasonic guided wave energy as a characteristic quantity, and finally realizing crack detection on the basin-type insulator according to the guided wave energy attenuation rate index. The detection method improves the sensitivity of the ultrasonic guided wave in detecting the micro cracks and has strong engineering application value.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative efforts.
FIG. 1 is a schematic structural diagram of an insulator surface crack detection device based on ultrasonic guided wave energy according to the present invention;
FIG. 2 is a flow chart of the insulator surface crack detection method based on ultrasonic guided wave energy provided by the invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. 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.
Example 1
Referring to the attached drawing 1, the embodiment of the invention discloses an insulator surface crack detection device based on ultrasonic guided wave energy, which comprises:
an upper computer 1;
the flaw detector 2 is connected with the upper computer 1, and the flaw detector 2 is used for generating pulse signals;
the ultrasonic detection unit 3, ultrasonic detection unit 3 set up on the insulator surface, and ultrasonic detection unit 3 is connected with flaw detector 2.
In a specific embodiment, the ultrasonic detection unit 3 includes a signal excitation end 31 and a signal receiving end 32, and both the signal excitation end 31 and the signal receiving end 32 are connected to the flaw detector 2;
the signal excitation end 31 is used for receiving the pulse signal and generating an ultrasonic signal, and the signal receiving end 32 is used for receiving the ultrasonic signal and sending the ultrasonic signal to the upper computer 1 through the flaw detector 2.
In a specific embodiment, the upper computer 1 is configured to process the received ultrasonic signal to obtain a corresponding ultrasonic signal energy attenuation rate, so as to implement surface crack detection on the insulator.
Further, referring to fig. 2, embodiment 1 of the present invention further provides a method for detecting cracks on an insulator surface based on ultrasonic guided wave energy, where the method includes:
the flaw detector 2 generates a pulse signal;
the ultrasonic detection unit 3 collects ultrasonic signals generated on the surface of the insulator and sends the ultrasonic signals to the upper computer 1;
the upper computer 1 processes the ultrasonic signals to obtain corresponding ultrasonic signal energy attenuation rate, and surface crack detection of the insulator is achieved.
In a specific embodiment, the method further comprises the following steps: the specific process of collecting the ultrasonic signals generated on the surface of the insulator comprises the following steps:
the ultrasonic detection unit 3 comprises a signal excitation end 31 and a signal receiving end 32;
the signal excitation end 31 receives the pulse signal and generates an ultrasonic signal, and the signal receiving end 32 is used for receiving the ultrasonic signal and sending the ultrasonic signal to the upper computer 1 through the flaw detector 2.
In a specific embodiment, the upper computer 1 obtains corresponding ultrasonic guided wave energy according to the ultrasonic signal, and further obtains the attenuation rate of the ultrasonic guided wave energy by taking the ultrasonic guided wave energy as a characteristic quantity.
In a specific embodiment, the specific expression of the ultrasonic signal energy attenuation rate is as follows:
in the formula, F0And F is the guided wave energy of the signal received by the sensor under the intact state and the crack state of the insulator respectively.
Specifically, the specific expression of the ultrasonic guided wave energy F is as follows:
in the formula, N is the sample length of the collected signal, v is the voltage value of the ith sampling point, and N can be selected according to actual needs.
Example 2
The method and the device provided by the embodiment 1 are utilized to detect the insulator, wherein the type of the detected insulator is 220kV single-phase air-insulated basin-type insulator, and the specific detection process is as follows:
(1) and 5 piezoelectric ceramic sensors with the same specification are arranged on the convex surface of the basin-type insulator, the thickness of the sensors is 2mm, the radius of the sensors is 6mm, and the center frequency of the sensors is 1 MHz. The signal excitation end 31 positioned at the top of the convex surface of the insulator is responsible for exciting ultrasonic waves, and the other 4 signal receiving ends 32 symmetrically distributed at the bottom of the convex surface are responsible for receiving ultrasonic signals.
(2) Ultrasonic testing was performed on the intact basin-type insulators with crack sizes of 5mm × 1mm × 2mm, 10mm × 1mm × 2mm, and 20mm × 1mm × 4mm, respectively, and the energy of the received signals was calculated, and the results are shown in table 1.
TABLE 1 basin-type insulator A in different states1Sensor signal energy
As can be seen from the measurement results of table 1: the energy attenuation rate is gradually increased as the energy of the received signal is gradually reduced along with the increase of the crack size, the energy attenuation rates of the ultrasonic received signal of the insulator with the crack size of 5mm multiplied by 1mm multiplied by 2mm and 10mm multiplied by 1mm multiplied by 2mm respectively reach 35.50 percent and 40.26 percent, the energy attenuation rate of the insulator with the crack size of 20mm multiplied by 1mm multiplied by 4mm further reaches 87.99 percent, the influence of machine errors and algorithm errors in the data processing process on data can be eliminated, and a large amount of experimental data conforms to the rule. Therefore, the size of the crack can be judged by utilizing the signal energy attenuation rate, and when the signal energy attenuation rate is between 0 and 35.5 percent, the size of the crack is basically smaller than 5mm multiplied by 1mm multiplied by 2 mm; when the signal energy attenuation rate is 35.5-40.26%, the crack size is between 5mm multiplied by 1mm multiplied by 2mm and 10mm multiplied by 1mm multiplied by 2 mm; when the signal energy attenuation rate is between 40.26 and 87.99 percent, the crack size is between 10mm multiplied by 1mm multiplied by 2mm and 20mm multiplied by 1mm multiplied by 4 mm; when the signal energy decay rate is greater than 87.99%, the crack size will be greater than 20mm by 1mm by 4 mm.
The embodiments in the present description are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other. The device disclosed by the embodiment corresponds to the method disclosed by the embodiment, so that the description is simple, and the relevant points can be referred to the method part for description.
The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims (7)
1. The utility model provides an insulator surface crack detection device based on supersound guided wave energy which characterized in that includes:
an upper computer (1);
the flaw detector (2) is connected with the upper computer (1), and the flaw detector (2) is used for generating pulse signals;
the ultrasonic detection unit (3), ultrasonic detection unit (3) set up on the insulator surface, just ultrasonic detection unit (3) with flaw detector (2) are connected.
2. The insulator surface crack detection device based on ultrasonic guided wave energy is characterized in that the ultrasonic detection unit (3) comprises a signal excitation end (31) and a signal receiving end (32), and the signal excitation end (31) and the signal receiving end (32) are both connected with the flaw detector (2);
the signal excitation end (31) is used for receiving the pulse signal and generating an ultrasonic signal, and the signal receiving end (32) is used for receiving the ultrasonic signal and sending the ultrasonic signal to the upper computer (1) through the flaw detector (2).
3. The insulator surface crack detection device based on ultrasonic guided wave energy as claimed in claim 2, wherein the upper computer (1) is used for processing the received ultrasonic signals to obtain the corresponding ultrasonic signal energy attenuation rate, so as to realize the surface crack detection of the insulator.
4. A method for detecting surface cracks of an insulator based on ultrasonic guided wave energy, which is characterized by comprising the following steps:
the flaw detector (2) generates a pulse signal;
the ultrasonic detection unit (3) collects ultrasonic signals generated on the surface of the insulator and sends the ultrasonic signals to the upper computer (1);
the upper computer (1) processes the ultrasonic signals to obtain corresponding ultrasonic signal energy attenuation rate, and surface crack detection of the insulator is achieved.
5. The method for detecting the insulator surface crack detection device based on the ultrasonic guided wave energy is characterized by further comprising the following steps: the specific process of collecting the ultrasonic signals generated on the surface of the insulator comprises the following steps:
the ultrasonic detection unit (3) comprises a signal excitation end (31) and a signal receiving end (32);
the signal excitation end (31) receives the pulse signal and generates an ultrasonic signal, and the signal receiving end (32) is used for receiving the ultrasonic signal and sending the ultrasonic signal to the upper computer (1) through the flaw detector (2).
6. The method for detecting the insulator surface crack detection device based on the ultrasonic guided wave energy according to the claim 5, characterized in that the upper computer (1) obtains the corresponding ultrasonic guided wave energy according to the ultrasonic signal, and further obtains the ultrasonic guided wave energy attenuation rate by taking the ultrasonic guided wave energy as a characteristic quantity.
7. The method for detecting the insulator surface crack detection device based on the ultrasonic guided wave energy as claimed in claim 6, wherein the specific expression of the ultrasonic signal energy attenuation rate is as follows:
in the formula, F0And F is the guided wave energy of the signal received by the sensor under the intact state and the crack state of the insulator respectively.
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| CN202110518740.4A CN113189206A (en) | 2021-05-12 | 2021-05-12 | Insulator surface crack detection device and method based on ultrasonic guided wave energy |
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| CN110531233A (en) * | 2019-09-25 | 2019-12-03 | 国网陕西省电力公司电力科学研究院 | GIS disc insulator surface state detection device and method based on ultrasonic wave injection |
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| CN110531233A (en) * | 2019-09-25 | 2019-12-03 | 国网陕西省电力公司电力科学研究院 | GIS disc insulator surface state detection device and method based on ultrasonic wave injection |
Non-Patent Citations (1)
| Title |
|---|
| 马君鹏等: "基于超声导波的盆式绝缘子缺陷检测及定位", 高电压技术, vol. 45, no. 12, pages 3941 - 3948 * |
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Inventor after: Li Xiaojing Inventor after: Jiao Guoxun Inventor after: Liu Hong Inventor after: Song Jiancheng Inventor after: Wang Wei Inventor after: Xu Yudong Inventor after: Gao Jinwu Inventor after: Li Guanliang Inventor after: Li Pengjiang Inventor after: Yu Hua Inventor after: Ge Jian Inventor after: Zheng Zhihong Inventor before: Li Xiaojing Inventor before: Song Jiancheng Inventor before: Gao Jinwu Inventor before: Li Guanliang Inventor before: Li Pengjiang Inventor before: Yu Hua Inventor before: Ge Jian Inventor before: Zheng Zhihong Inventor before: Jiao Guoxun Inventor before: Liu Hong |
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