CN117330586A - Method and related device for detecting external insulation damage of power system - Google Patents
Method and related device for detecting external insulation damage of power system Download PDFInfo
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Abstract
The invention discloses a method and a related device for detecting external insulation damage of a power system, wherein the method comprises the following steps: collecting defect information of a physical space by using ultra-wideband electromagnetic pulse and synthetic aperture radar SAR; based on the defect information, a back projection algorithm BP is used to reconstruct the defect image. The method for detecting the external insulation defects adopts ultra-wide band electromagnetic pulse with strong penetrability and high resolution, overcomes the defects of the traditional method for detecting the external insulation defects, improves the efficiency and accuracy of defect detection imaging, and can realize nondestructive and online detection, thereby greatly improving the nondestructive online detection capability of the external insulation defects. The method can develop researches such as an external insulation process improvement test and a state online detection, provides references for determining damage positions and insulation replacement, and has important significance for guaranteeing safe operation of a power grid. In addition, the external insulation inspection type defect detection can be carried out by matching with an unmanned aerial vehicle system, the method has important guiding significance for insulation protection early warning and the like of power grid equipment, and insulation safety of the power grid equipment is guaranteed.
Description
Technical Field
The invention belongs to the technical field of damage detection, relates to a detection method based on ultra-wide band electromagnetic pulse, and in particular relates to an external insulation damage detection method and a related device of a power system.
Background
At present, the existing insulator damage detection method is low in observation efficiency and easy to be interfered by acceptors. For example, deng Gonglei discloses that an ultrasonic method utilizes heterogeneous interface echo characteristics when ultrasonic waves propagate in different media to judge insulator defects in "composite insulator detection based on ultrasonic guided waves", and the scheme cannot realize online detection of external insulation internal damage; the scheme disclosed in "Tomography Technology of GIS Basin Insulator Based on Laser Ultrasonic" by wang et al has problems of reduced detection accuracy of field noise, insufficient detection accuracy in composite materials, and the like. Zhang Zhonghao et al disclose a terahertz detection method in the research of terahertz wave-based composite insulator interface detection, which detects and distinguishes the defect and normal part of an insulator according to the fingerprint characteristics of substances carried by terahertz reflection waves, and requires densely collecting echo signals on the surface of an object to obtain a projection image of the defect, so that the detection complexity is high. The terahertz detection system is precise and complex, is easily interfered by outdoor strong light, air humidity and external strong electromagnetic fields, and the safe distance of high-voltage equipment can seriously obstruct the practical engineering application of the terahertz method, so that the electrified detection is difficult to realize.
The ultra-wideband electromagnetic pulse refers to transient electromagnetic radiation with the percentage bandwidth being more than 25%, the rising edge of the time domain waveform is of the order of subnanoseconds or even picoseconds, the frequency domain band ratio can reach more than 10:1, and the ultra-wideband electromagnetic pulse has unique application advantages in the field of target detection and identification. The ultra-wideband detection has the advantages of wide frequency spectrum, strong penetrability, high resolution and the like, and has great application value in the aspect of detecting the external insulation defects of the power system, especially the internal defects of the insulation components. The broadband characteristic of the ultra-wideband pulse enables the ultra-wideband pulse to penetrate different media so as to have nondestructive detection capability.
Disclosure of Invention
The invention aims to solve the problem of detection of external insulation damage of a power system, and provides a method and a related device for detecting the external insulation damage of the power system so as to realize nondestructive online detection of the external insulation damage. A method of combining a synthetic aperture radar (Synthetic Aperture Radar, SAR) with a Back Projection algorithm (BP) for defect imaging is provided, and a defect imaging method based on ultra-wideband electromagnetic pulses is provided.
In order to achieve the above purpose, the invention is realized by adopting the following technical scheme:
in a first aspect, the present invention provides a method for detecting insulation damage outside an electric power system, including the steps of:
collecting defect information of a physical space by using ultra-wideband electromagnetic pulse and synthetic aperture radar SAR;
based on the defect information, a back projection algorithm BP is used to reconstruct the defect image.
In a second aspect, the present invention provides an external insulation damage detection system for an electric power system, including:
the defect information extraction module is used for collecting defect information of a physical space by utilizing ultra-wideband electromagnetic pulse and using a synthetic aperture radar SAR;
and the defect image reconstruction module is used for reconstructing a defect image by using a back projection algorithm BP based on the defect information.
In a third aspect, the invention provides an electronic device comprising a memory, a processor and a computer program stored in the memory and executable on the processor, the processor implementing the steps of the method as described above when executing the computer program.
In a fourth aspect, the present invention provides a computer readable storage medium storing a computer program which when executed by a processor performs the steps of a method as described above.
Compared with the prior art, the invention has the following beneficial effects:
the invention mainly divides the detection of the external insulation damage of the power system based on ultra-wideband electromagnetic pulse into two parts, namely collecting reflected signals in SAR mode and processing the signals by BP algorithm to obtain a defect image. Firstly, a transmitting antenna is aligned with a measured object and moves around the measured object, simultaneously transmits an ultra-wideband electromagnetic pulse signal, and a receiving antenna obtains a reflected signal containing material distribution information and stores data. Secondly, separating and amplifying the reflection signals with small defects from the original reflection signals by a defect extraction signal processing method, extracting the energy distribution image amplitude of each detection azimuth by a BP algorithm according to the propagation time of electromagnetic waves, and performing coherent processing on images with different azimuth to obtain BP images of the defects. The method for detecting the external insulation defects adopts ultra-wide band electromagnetic pulse with strong penetrability and high resolution, overcomes the defects of the traditional method for detecting the external insulation defects, improves the efficiency and accuracy of defect detection imaging, and can realize nondestructive and online detection, thereby greatly improving the nondestructive online detection capability of the external insulation defects. On the basis, research such as external insulation process improvement test and state online detection can be carried out, reference is provided for determining damage positions and insulation replacement, and the method has important significance for guaranteeing safe operation of a power grid. In addition, the external insulation inspection type defect detection can be carried out by matching with an unmanned aerial vehicle system, the method has important guiding significance for insulation protection early warning and the like of power grid equipment, and insulation safety of the power grid equipment is guaranteed.
Drawings
For a clearer description of the technical solutions of the embodiments of the present invention, the drawings that are needed in the embodiments will be briefly described below, it being understood that the following drawings only illustrate some embodiments of the present invention and should not be considered as limiting the scope, and other related drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
FIG. 1 is a flow chart of the method of the present invention.
Fig. 2 is a schematic diagram of the system of the present invention.
Fig. 3 is a schematic diagram of damage detection based on ultra-wideband electromagnetic pulses.
Fig. 4 is a schematic diagram of defect imaging based on the SAR-BP method.
Fig. 5 is a configuration diagram of an external insulation defect detection test.
Fig. 6 is a schematic view of imaging region division.
Fig. 7 is a schematic flow chart of external insulation damage detection.
FIG. 8 is a graph of simulation results of using CST software to verify the effectiveness of a defect detection method; wherein, (a) is an object to be tested with spherical defects, and (b) is a simulation test chart.
Fig. 9 is a coherent addition processed image of a defect.
Fig. 10 is a coherent multiplication processed image of a defect.
Detailed Description
For the purpose of making the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is apparent that the described embodiments are some embodiments of the present invention, but not all embodiments of the present invention. The components of the embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations.
Thus, the following detailed description of the embodiments of the invention, as presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
It should be noted that: like reference numerals and letters denote like items in the following figures, and thus once an item is defined in one figure, no further definition or explanation thereof is necessary in the following figures.
In the description of the embodiments of the present invention, it should be noted that, if the terms "upper," "lower," "horizontal," "inner," and the like indicate an azimuth or a positional relationship based on the azimuth or the positional relationship shown in the drawings, or the azimuth or the positional relationship in which the inventive product is conventionally put in use, it is merely for convenience of describing the present invention and simplifying the description, and does not indicate or imply that the apparatus or element to be referred to must have a specific azimuth, be configured and operated in a specific azimuth, and thus should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and the like, are used merely to distinguish between descriptions and should not be construed as indicating or implying relative importance.
Furthermore, the term "horizontal" if present does not mean that the component is required to be absolutely horizontal, but may be slightly inclined. As "horizontal" merely means that its direction is more horizontal than "vertical", and does not mean that the structure must be perfectly horizontal, but may be slightly inclined.
In the description of the embodiments of the present invention, it should also be noted that, unless explicitly specified and limited otherwise, the terms "disposed," "mounted," "connected," and "connected" should be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art according to the specific circumstances.
The invention is described in further detail below with reference to the attached drawing figures:
referring to fig. 1, the embodiment of the invention discloses a method for detecting external insulation damage of a power system, which comprises the following steps:
s1, utilizing ultra-wideband electromagnetic pulse, and collecting defect information of a physical space by using a synthetic aperture radar SAR; the method comprises the following steps:
s1-1, transmitting ultra-wideband electromagnetic pulse to an ultra-wideband antenna when the antenna moves around a measured object;
s1-2, the ultra-wideband reflection signals obtained by the receiving antenna form a data space, and the ultra-wideband reflection signals store the material distribution characteristics of the target space, so that defect signals are obtained. The defect signal is obtained according to the following method:
s1-2-1, performing defect extraction on the ultra-wideband reflection signal;
s1-2-2 adopts an average inhibition signal processing method, and takes reflected signals generated by an external insulation external regular structure as clutter and filters the clutter to obtain defect signals.
According to the synthetic aperture radar SAR, the longer virtual antenna is synthesized by combining and processing echo signals received from different positions by a single antenna, so that imaging with higher resolution is obtained. The transmitting antenna and the receiving antenna of the synthetic aperture radar SAR simultaneously do circular motion around the measured object, and two-dimensional high resolution is obtained.
S2, reconstructing a defect image by using a back projection algorithm BP based on defect information, wherein the defect image is specifically as follows:
s2-1, extracting a calculated amplitude of the back projection algorithm BP from an ultra-wideband waveform of a reflected signal according to the distance and the propagation time between a target point and a transmitting antenna and a receiving antenna by using the back projection algorithm BP, and obtaining energy distribution corresponding to a single echo signal;
s2-2, after the images obtained by processing the echo signals of each position are subjected to coherent superposition, the intensity of the pixel points of the defects is enhanced, and defect imaging is obtained.
The back projection algorithm BP realizes high-resolution imaging through the coherent processing of echo data in a time domain, and can obtain information in an object, and the method is concretely as follows:
echoes s received by antennas of the first group l (t) is:
wherein n is n reflection points in total in a target space g (x, y), and the target space g (x, y) is a physical area of radar detection, wherein x and y represent directions; sigma (sigma) n For the reflection coefficient of the reflection point in the target space, the center is located at (x n ,y n ) N=1, 2, …; p (t) is a radar emission pulse signal; t is the time from the moment of pulse emission; v is the propagation speed of electromagnetic waves; (u) l1 0) and (u) l2 0) is the receiving and transmitting position of the synthetic aperture radar, L is the number of detection sequences, l=1, 2, …, L;
dividing the imaging region into N×M grids according to the resolution, and dividing the imaging region into N×M grids for the mth point (x m ,y m ) The coherent addition imaging algorithm of the back projection algorithm BP is as follows:
wherein L is the group number of the synthetic aperture radar, S l Is the time domain waveform of the first reflected signal, t ml The propagation time of the electromagnetic wave corresponding to the mth point in the grid;
the coherence multiplication imaging algorithm using the back projection algorithm BP highlights the abnormal position, concretely as follows:
imaging the single echo data, and judging the sum of the distances from the scatterer to the transmitting antenna and the receiving antenna according to the echo signals; if the receiving and transmitting antennas are not positioned at the same position, the scatterer is any point on an elliptical track; the echo received by the antenna at each position can obtain the image of the scatterer, the intensity of the scattering point is enhanced after coherent superposition according to time delay, and other positions can be submerged in the background, so that the imaging of the back projection algorithm BP is realized.
As shown in fig. 2, an embodiment of the present invention provides an external insulation damage detection system for an electric power system, including:
the defect information extraction module is used for collecting defect information of a physical space by utilizing ultra-wideband electromagnetic pulse and using a synthetic aperture radar SAR;
and the defect image reconstruction module is used for reconstructing a defect image by using a back projection algorithm BP based on the defect information.
The principle of the invention is as follows:
the invention establishes an external insulation defect detection method based on ultra-wideband electromagnetic pulse, and the key point is that a one-dimensional time signal of the ultra-wideband electromagnetic pulse is converted into a defect image.
1) SAR-BP-based defect detection method and process
The ultra-wideband electromagnetic pulse is used for detecting the external insulation damage and is divided into two parts, and ultra-wideband reflection signals and BP algorithm imaging are collected in an SAR mode, as shown in figure 3. The former collects the defect information of the physical space into the data space, and the latter reconstructs the data into an image, so that the detection and imaging of the defect are finally realized.
The specific principle of detection is shown in fig. 4. Firstly, an ultra-wideband antenna emits ultra-wideband electromagnetic pulse to an object to be measured when the antenna moves around the object to be measured, and a reflected signal obtained by the receiving antenna forms a data space, wherein the material distribution characteristics of a target space are stored. And secondly, extracting BP calculation amplitude from the reflected ultra-wideband waveform according to the distance and the propagation time between the target point and the transmitting antenna and the receiving antenna by using a backward projection algorithm, thereby obtaining the energy distribution corresponding to the single echo. And finally, after the images obtained by processing echo signals of each position are coherently superimposed, the intensity of defective pixel points is enhanced, and other positions are submerged in the background, so that defect imaging is obtained.
2) SAR-BP imaging method
SAR synthesizes longer virtual antennas by combining echo signals received from different locations by a single antenna, thereby obtaining higher resolution imaging. The invention uses CSAR method, the transmitting antenna and the receiving antenna do circular motion around the measured object at the same time, which can obtain two-dimensional high resolution, and the problem of incomplete information caused by linear SAR small angle observation range can not occur.
The BP algorithm is initially a SAR time domain imaging algorithm derived from the projection slice theory of CT imaging, which achieves high resolution imaging by coherent processing of echo data in the time domain. The algorithm principle is simple, the accurate position of interface reflection is not required to be known during imaging, and information in the object can be obtained.
The target space g (x, y) is the physical area of radar detection, where x, y represent the azimuth. N reflection coefficients sigma in the target space n Is centered at (x) n ,y n ) N=1, 2, …. The L groups of receiving and transmitting positions provided with the synthetic aperture radar are respectively positioned at (u) l1 0) and (u) l2 0), l=1, 2, …, L. The radar transmit pulse signal is p (t).
The echoes received by the first set of antennas can be expressed as:
wherein n is n reflection points in total in a target space g (x, y), and the target space g (x, y) is a physical area of radar detection, wherein x and y represent directions; sigma (sigma) n For the reflection coefficient of the reflection point in the target space, the center is located at (x n ,y n ) N=1, 2, …; p (t) is a radar emission pulse signal; t is the time from the moment of pulse emission; v is the propagation speed of electromagnetic waves; (u) l1 0) and (u) l2 0) is the receiving and transmitting position of the synthetic aperture radar, L is the number of detection sequences, l=1, 2, …, L;
the imaging region as shown in fig. 6 is divided into n×m grids according to resolution size, and for the mth point (x m ,y m ) The BP coherent addition imaging algorithm is as follows:
wherein L is the group number of the synthetic aperture radar, S l Is the time domain waveform of the first reflected signal, t ml The propagation time of the electromagnetic wave corresponding to the mth point in the grid;
sometimes because of interference of the clutter, the distinction between the damage and the normal part in the imaging is not obvious, the BP coherent multiplication imaging algorithm can be used for highlighting the abnormal position, enhancing the focusing effect, and the algorithm is as follows:
and imaging the single echo data, and judging the sum of the distances from the scattering body to the transmitting antenna and the receiving antenna according to the echo signals. If the transceiver antennas are not co-located, the scatterer may be any point on an elliptical trajectory. The echo received by the antenna at each position can obtain the image of the scatterer, the intensity of the scattering point is enhanced after coherent superposition according to time delay, and other positions can be submerged in the background, namely BP imaging.
3) Small defect detection technology
Because the defects are relatively small compared with the whole external insulation, the information of the defects in the reflected signals is less and cannot be imaged, so that the defects of the ultra-wideband reflected signals are required to be extracted first. And adopting an average suppression signal processing method, regarding the reflected signals generated by the external insulation external regular structure as clutter and filtering the clutter to obtain defective reflected signals, wherein the processing method is to take the average value of all the reflected signals subtracted from the reflected signals as a defective signal.
Examples
The specific implementation flow of the external insulation defect detection method based on ultra-wideband electromagnetic pulse is shown in fig. 7.
And using CST software simulation results to verify the effectiveness of the defect detection method. The object to be measured is a cylinder of ceramic material with a diameter of 160mm, and the defect is a circular cavity with a radius of 5mm from the axis of 48mm, as shown in figure 8. The transmitting antenna and the receiving antenna are ultra-wideband antennas, the available bandwidth is the same as that of the pulse source, and the available bandwidth is 0.3-3 GHz. The defect detection system configuration is shown in fig. 5.
In the simulation, the measured object has only a single-layer medium, and the single-layer refraction algorithm is used for imaging the measured object. And performing defect detection on the defect insulator and the perfect insulator by using an ultra-wideband method respectively, wherein a coherent addition image is shown in fig. 9, and a coherent multiplication amplification image is shown in fig. 10.
The defect insulator has a significant energy enhancement inside, which is the location of the defect. The shape of the defect can be roughly considered to be a circle from the coherent addition image, and the defect position is determined to be 44.7mm from the axis, the deviation of the actual value is 6.9%, the radius is 5mm, and the angle position is the same as the actual value and has no deviation. The boundary between the object to be measured and the defect is not shown in the coherent multiplication image, but the artifact is almost eliminated. And judging that the distance between the defect center and the center of the measured object is 50mm according to the maximum value, wherein the relative deviation between the defect center and the actual value is 4.2%, and the angle position has no deviation. Therefore, the invention can effectively detect the shape, position and size of the defect.
The embodiment of the invention provides computer equipment. The computer device of this embodiment includes: a processor, a memory, and a computer program stored in the memory and executable on the processor. The steps of the various method embodiments described above are implemented when the processor executes the computer program. Alternatively, the processor may implement the functions of the modules/units in the above-described device embodiments when executing the computer program.
The computer program may be divided into one or more modules/units, which are stored in the memory and executed by the processor to accomplish the present invention.
The computer equipment can be a desktop computer, a notebook computer, a palm computer, a cloud server and other computing equipment. The computer device may include, but is not limited to, a processor, a memory.
The processor may be a central processing unit (Central Processing Unit, CPU), but may also be other general purpose processors, digital signal processors (Digital Signal Processor, DSP), application specific integrated circuits (Application Specific Integrated Circuit, ASIC), off-the-shelf programmable gate arrays (Field-Programmable Gate Array, FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, or the like.
The memory may be used to store the computer program and/or modules, and the processor may implement various functions of the computer device by running or executing the computer program and/or modules stored in the memory, and invoking data stored in the memory.
The modules/units integrated with the computer device may be stored in a computer readable storage medium if implemented in the form of software functional units and sold or used as stand alone products. Based on such understanding, the present invention may implement all or part of the flow of the method of the above embodiment, or may be implemented by a computer program to instruct related hardware, where the computer program may be stored in a computer readable storage medium, and when the computer program is executed by a processor, the computer program may implement the steps of each of the method embodiments described above. Wherein the computer program comprises computer program code which may be in source code form, object code form, executable file or some intermediate form etc. The computer readable medium may include: any entity or device capable of carrying the computer program code, a recording medium, a U disk, a removable hard disk, a magnetic disk, an optical disk, a computer Memory, a Read-Only Memory (ROM), a random access Memory (RAM, random Access Memory), an electrical carrier signal, a telecommunications signal, a software distribution medium, and so forth. It should be noted that the computer readable medium contains content that can be appropriately scaled according to the requirements of jurisdictions in which such content is subject to legislation and patent practice, such as in certain jurisdictions in which such content is subject to legislation and patent practice, the computer readable medium does not include electrical carrier signals and telecommunication signals.
The above is only a preferred embodiment of the present invention, and is not intended to limit the present invention, but various modifications and variations can be made to the present invention by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (10)
1. The method for detecting the external insulation damage of the power system is characterized by comprising the following steps of:
collecting defect information of a physical space by using ultra-wideband electromagnetic pulse and synthetic aperture radar SAR;
based on the defect information, a back projection algorithm BP is used to reconstruct the defect image.
2. The method for detecting external insulation damage of power system according to claim 1, wherein the collecting defect information of the physical space using the synthetic aperture radar SAR using ultra wideband electromagnetic pulse comprises:
the ultra-wideband antenna transmits ultra-wideband electromagnetic pulse to the object to be measured when the ultra-wideband antenna moves around the object to be measured;
the ultra-wideband reflected signals obtained by the receiving antenna form a data space, and the ultra-wideband reflected signals store the material distribution characteristics of the target space, so that defect signals are obtained.
3. The method for detecting an external insulation damage of a power system according to claim 2, wherein reconstructing a defect image using a back projection algorithm BP based on defect information comprises:
the method comprises the steps of extracting a calculated amplitude of a back projection algorithm BP from an ultra-wideband waveform of a reflected signal according to the distance and propagation time between a target point and a transmitting antenna and between the target point and a receiving antenna by using the back projection algorithm BP, and obtaining energy distribution corresponding to a single echo signal;
and after the images obtained by processing the echo signals of each position are subjected to coherent superposition, the intensity of the pixel points of the defects is enhanced, and defect imaging is obtained.
4. The method for detecting external insulation damage of power system according to claim 2, wherein the synthetic aperture radar SAR synthesizes longer virtual antennas by combining echo signals received from different positions by a single antenna, thereby obtaining higher resolution imaging.
5. The method for detecting external insulation damage of power system according to claim 4, wherein the transmitting and receiving antennas of the synthetic aperture radar SAR simultaneously do circular motion around the object to be detected, thereby obtaining two-dimensional high resolution.
6. The method for detecting external insulation damage of an electric power system according to any one of claims 1 to 3, wherein the back projection algorithm BP realizes high resolution imaging by coherent processing of echo data in a time domain, and can obtain information inside an object, specifically as follows:
echoes s received by antennas of the first group l (t) is:
wherein n is n reflection points in total in a target space g (x, y), and the target space g (x, y) is a physical area of radar detection, wherein x and y represent directions; sigma (sigma) n For the reflection coefficient of the reflection point in the target space, the center is located at (x n ,y n ) N=1, 2, …; p (t) is a radar emission pulse signal; t is the time from the moment of pulse emission; v is the propagation speed of electromagnetic waves; (u) l1 0) and (u) l2 0) is the receiving and transmitting position of the synthetic aperture radar, L is the number of detection sequences, l=1, 2, …, L;
dividing the imaging region into N×M grids according to the resolution, and dividing the imaging region into N×M grids for the mth point (x m ,y m ) The coherent addition imaging algorithm of the back projection algorithm BP is as follows:
wherein L is the group number of the synthetic aperture radar, S l Is the time domain waveform of the first reflected signal, t ml The propagation time of the electromagnetic wave corresponding to the mth point in the grid;
the coherence multiplication imaging algorithm using the back projection algorithm BP highlights the abnormal position, concretely as follows:
imaging the single echo data, and judging the sum of the distances from the scatterer to the transmitting antenna and the receiving antenna according to the echo signals; if the receiving and transmitting antennas are not positioned at the same position, the scatterer is any point on an elliptical track; the echo received by the antenna at each position can obtain the image of the scatterer, the intensity of the scattering point is enhanced after coherent superposition according to time delay, and other positions can be submerged in the background, so that the imaging of the back projection algorithm BP is realized.
7. The method for detecting external insulation damage of power system according to claim 2, wherein the defect signal is obtained according to the following method:
performing defect extraction on the ultra-wideband reflection signal;
and adopting an average inhibition signal processing method, regarding the reflected signals generated by the external insulation external regular structure as clutter and filtering out the clutter to obtain defect signals.
8. An external insulation damage detection system for an electric power system, comprising:
the defect information extraction module is used for collecting defect information of a physical space by utilizing ultra-wideband electromagnetic pulse and using a synthetic aperture radar SAR;
and the defect image reconstruction module is used for reconstructing a defect image by using a back projection algorithm BP based on the defect information.
9. An electronic device comprising a memory, a processor and a computer program stored in the memory and executable on the processor, characterized in that the processor implements the steps of the method according to any of claims 1-7 when the computer program is executed.
10. A computer readable storage medium storing a computer program, characterized in that the computer program when executed by a processor implements the steps of the method according to any one of claims 1-7.
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