A nondestructive detection method, system and device for insulator defects

Abstract

The present invention relates to a nondestructive detection method, system, and equipment for insulator defects, comprising: obtaining first temperature change data for each pixel of an insulator fitting after heating and second temperature change data for the insulator after heating; determining the maximum temperature value of each first temperature change data, and determining the shortest time for temperature drop in all first temperature change data; shifting the time corresponding to the maximum temperature value to the same time point, and determining reconstructed data based on the shortest time; analyzing the characteristics of the reconstructed data at the fundamental frequency, and detecting defects in the fitting based on the characteristics of the reconstructed data; analyzing the characteristics of the second temperature change data, and determining defects in the insulator based on the characteristics of the second temperature change data; the characteristics of the reconstructed data include amplitude characteristics and phase characteristics. The present invention can adapt to the detection of different insulator structures, reduce the error rate, and is applicable to the field of power equipment detection technology.

Description

Technical Field

[0001] The present invention relates to the technical field of power equipment detection, and in particular to a non-destructive detection method, system and equipment for insulator defects. Background Art

[0002] Insulators are susceptible to temperature fluctuations in extreme climates. Large temperature fluctuations can cause cracks, such as internal or surface cracks, due to thermal expansion and contraction. Currently, existing crack defect detection methods primarily include visual inspection, electric field measurement, infrared imaging, and ultraviolet imaging. These temperature fluctuations can interfere with temperature measurement and discharge status, impacting defect detection and leading to a high rate of false positives among existing detection technologies. Summary of the Invention

[0003] In view of this, an object of the present invention is to provide a non-destructive detection method, system and equipment for insulator defects, which can adapt to the detection of different insulator structures and reduce the misjudgment rate.

[0004] In one aspect, the present invention provides a method for nondestructive detection of insulator defects, comprising the following steps:

[0005] Acquire first temperature change data of each pixel point after the insulator hardware is heated and second temperature change data of the insulator after the insulator is heated;

[0006] Determine the maximum temperature value of each first temperature change data, and determine the shortest time of temperature drop in all first temperature change data;

[0007] Shifting the time corresponding to the maximum temperature value to the same time point, and determining the reconstructed data according to the shortest time;

[0008] Analyze the characteristics of the reconstructed data at the fundamental frequency, and detect defects in the hardware based on the characteristics of the reconstructed data; analyze the characteristics of the second temperature change data, and determine defects in the insulator based on the characteristics of the second temperature change data; the characteristics of the reconstructed data include amplitude characteristics and phase characteristics.

[0009] Optionally, determining the reconstructed data according to the shortest time specifically includes: taking the same time point as the starting point, and intercepting temperature data after the maximum temperature value and within the shortest time as the reconstructed data.

[0010] Optionally, analyzing the characteristics of the reconstructed data at the fundamental frequency and detecting defects of the hardware according to the characteristics of the reconstructed data specifically includes:

[0011] Performing Fourier transform on the reconstructed data at a base frequency, and determining amplitude characteristics and phase characteristics of the reconstructed data according to a result of the Fourier transform;

[0012] A secondary value map is reconstructed according to the amplitude feature and a phase map is reconstructed according to the phase feature, and a defect position is determined according to the secondary value map and the phase map, and the size of the defect is measured according to the peak value of the defect position in the phase map.

[0013] On the other hand, the present invention provides a nondestructive detection system for insulator defects, wherein the insulator includes a hardware and an insulator, and the nondestructive detection system includes an excitation power supply module, an electromagnetic excitation module, a photothermal excitation module, an infrared thermal imaging module, a motion module, and an industrial control computer;

[0014] The excitation power supply module is used to provide power to the electromagnetic excitation module and the photothermal excitation module;

[0015] The electromagnetic excitation module is used to emit electromagnetic waves to generate electromagnetic induction with the hardware to heat the hardware;

[0016] The photothermal excitation module is used to emit a light beam to heat the insulator;

[0017] The infrared thermal imaging module is used to obtain first temperature change data of the hardware after heating and / or second temperature change data of the insulator after heating;

[0018] The motion module is used to move the electromagnetic excitation module, the photothermal excitation module or the infrared thermal imaging module;

[0019] The industrial computer is used to implement the above method.

[0020] Optionally, the excitation power supply module is specifically used to provide the electromagnetic excitation module with a first power supply whose first power supply parameters correspond to the material and / or shape of the hardware; the first power supply parameters include power supply size, power supply frequency and loading time.

[0021] Optionally, the excitation power supply module is specifically configured to provide the photothermal excitation module with a second power supply whose second power supply parameters correspond to the first geometric parameters of the insulator; the second power supply parameters include power supply power and loading time.

[0022] Optionally, the photothermal excitation module includes one or more light sources selected from halogen lamps, downlights, flash lamps or array lasers, and the industrial computer is further used to determine the light source for heating according to the type of the insulator, and turn on the light source for heating in the photothermal excitation module to heat the insulator.

[0023] Optionally, the infrared thermal imaging module includes several lenses with different focal lengths; the industrial computer is also used to select at least one lens to obtain the first temperature change data of the hardware after heating and / or the second temperature change data of the insulator after heating based on the second geometric parameters and accuracy of the hardware and / or the insulator.

[0024] Optionally, the electromagnetic excitation module is specifically used to scan and heat the hardware.

[0025] On the other hand, the present invention provides an electronic device, comprising a memory and a processor, wherein the memory stores a computer program, and the processor implements the above method when executing the computer program.

[0026] The implementation of the present invention includes the following beneficial effects: respectively obtaining the temperature change data of the insulator hardware and the insulator part after heating, and adopting a targeted processing method for the specific part according to the characteristics of the insulator, so that the present invention is suitable for defect detection of the specific part. At the same time, a defect identification method based on the phase characteristics and amplitude characteristics at the fundamental frequency is adopted. The thermal wave propagation depth at this frequency is the deepest, and the defect detection signal-to-noise ratio is the highest, which can better present the state of the defect. The use of fundamental frequency data avoids the influence of invalid data in multi-dimensional data, thereby reducing the misjudgment rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] 1-Electromagnetic induction coil; 2-Photothermal excitation source; 3-Infrared thermal imaging module; 4-Motion module; 5-Industrial computer; 6-Excitation power supply module; 7-Porcelain insulator to be tested.

[0028] Figure 1 This is a flowchart of the steps of a nondestructive detection method for insulator defects provided by the present invention;

[0029] Figure 2 This is a schematic diagram of a data reconstruction process provided by the present invention;

[0030] Figure 3 This is a schematic diagram of a module of a nondestructive detection system for insulator defects provided by the present invention;

[0031] Figure 4 This is a structural schematic diagram of a nondestructive detection system for insulator defects provided by the present invention;

[0032] Figure 5 It is a structural schematic diagram of an electronic device provided by the present invention. DETAILED DESCRIPTION

[0033] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. The step numbers in the following embodiments are provided for ease of description only and do not limit the order of the steps. The order of execution of the steps in the embodiments can be adaptively adjusted according to the understanding of those skilled in the art.

[0034] The terms used in the embodiments of the present application are for the purpose of describing specific embodiments only and are not intended to limit the embodiments of the present application. The singular forms "a," "the," and "the" used in the embodiments of the present application and the appended claims are also intended to include plural forms unless the context clearly indicates otherwise. It should also be understood that the term "and / or" used herein refers to and includes any or all possible combinations of one or more associated listed items.

[0035] When the following description refers to the accompanying drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present application. On the contrary, they are merely examples of devices and methods consistent with some aspects of the present application as detailed in the appended claims. In the description of the present application, it should be understood that the terms "first", "second", etc. are only used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence, nor can they be understood as indicating or implying relative importance. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to the specific circumstances.

[0036] Additionally, in this application, unless otherwise specified, "plurality" refers to two or more. "And / or" describes the relationship between associated objects, indicating that three possible relationships exist. For example, "D and / or E" can mean: D exists alone, D and E exist simultaneously, or E exists alone. The character " / " generally indicates that the associated objects are in an "or" relationship.

[0037] In some embodiments, as Figure 1 As shown, Figure 1 The present invention provides a nondestructive detection method for insulator defects, which includes the following steps:

[0038] S1. Acquire first temperature change data of each pixel point after the insulator hardware is heated and second temperature change data of the insulator after the insulator is heated.

[0039] An insulator includes a hardware and an insulator. The hardware includes a plurality of pixels. The first temperature change data and the second temperature change data may be, but are not limited to, temperature change curves. Each pixel may be represented by at least one temperature change curve.

[0040] S2. Determine the maximum temperature value of each first temperature change data, and determine the shortest time of temperature drop in all first temperature change data.

[0041] Specifically, if Figure 2 As shown, Figure 2 This is a schematic diagram of the data reconstruction process. In the figure, F represents the hardware to be tested, 1 represents the electromagnetic induction coil, and 8 represents the reconstructed data. For example, three pixels A, B, and C on the hardware have three temperature change curves, A, B, and C, respectively. The maximum temperature value of each temperature change curve is determined and the corresponding time is recorded.

[0042] The shortest temperature drop time in all the first temperature change data is determined. For example, the temperature drop time of the temperature change curve C in the figure is the shortest after the temperature maximum, and this is used as the shortest temperature drop time.

[0043] S3. Shift the time corresponding to the maximum temperature value to the same time point, and determine the reconstructed data based on the shortest time;

[0044] The same time point may be a time point corresponding to the maximum temperature value of any temperature change curve, or may not be a time point on the temperature change curve.

[0045] Specifically, when the time corresponding to the maximum temperature value is shifted to the same time point, the remaining time points are also shifted accordingly. With the same time point as the starting point, the temperature data after the maximum temperature value and within the shortest time are intercepted as the reconstructed data. Figure 2 , the temperature data within time C is intercepted as the reconstructed data.

[0046] S4. Analyze the characteristics of the reconstructed data at the fundamental frequency, and detect defects in the hardware according to the characteristics of the reconstructed data; analyze the characteristics of the second temperature change data, and determine defects in the insulator according to the characteristics of the second temperature change data.

[0047] The features of the reconstructed data include amplitude features and phase features. The features of the second temperature change data may be, but are not limited to, amplitude features, phase features, maximum temperature, temperature change rate, and the like.

[0048] Specifically, the reconstructed data is Fourier transformed at the base frequency, as shown in formula (1):

[0049] (1)

[0050] in, T ( k ) is the reconstructed data, F n Indicates the n The fast Fourier transform result of the frequency components isL represents the time dimension of the reconstructed data, represents the exponential operation. At the fundamental frequency, n =1.

[0051] Determine the amplitude characteristics of the reconstructed data based on the results of Fourier transform and phase characteristics , as shown in formulas (2) and (3):

[0052] (2)

[0053] (3)

[0054] in, express The real part of express The imaginary part of Represents the inverse tangent function.

[0055] The secondary value graph is reconstructed based on the amplitude characteristics and the phase graph is reconstructed based on the phase characteristics. The position where the data change is greater than the preset value, i.e., the defect position, is located by combining the secondary value graph and the phase graph. The size of the defect is measured based on the peak value of the defect position in the phase graph. For example, the 5 / 12 peak width of the defect position in the phase graph is used to represent the size of the defect. Compared with the results of the existing half-peak width measurement, the problem of oversized size measurement caused by lateral heat diffusion is reduced, and the measurement accuracy of the defect size is improved.

[0056] On the other hand, Figure 3 As shown, Figure 3 The present invention provides a nondestructive detection system for insulator defects. The insulator includes a hardware and an insulator. The nondestructive detection system includes an excitation power supply module, an electromagnetic excitation module, a photothermal excitation module, an infrared thermal imaging module, a motion module, and an industrial control computer.

[0057] Excitation power supply module, used to provide power to the electromagnetic excitation module and the photothermal excitation module;

[0058] The electromagnetic excitation module is used to emit electromagnetic waves to generate electromagnetic induction with the hardware to heat the hardware;

[0059] A photothermal excitation module is used to emit a light beam to heat the insulator;

[0060] Infrared thermal imaging module, used to obtain first temperature change data after the hardware is heated and / or second temperature change data after the insulator is heated;

[0061] A motion module, used to move the electromagnetic excitation module, the photothermal excitation module or the infrared thermal imaging module;

[0062] An industrial computer is used to implement the aforementioned method.

[0063] Specifically, the modules of the nondestructive testing system can be connected by communication, or by lines or mechanical connections. The overall architecture can be that the motion module drives the excitation power module, electromagnetic excitation module, photothermal excitation module and infrared thermal imaging module to move near the insulator. For example, the motion module can be a drone, etc., to achieve online detection of the insulator. In addition, the overall architecture can also be as follows: Figure 4 As shown, Figure 4 The schematic diagram of the structure of a nondestructive detection system for insulator defects is shown in FIG.

[0064] The excitation power supply module may include multiple power supplies to provide power to the electromagnetic excitation module and the photothermal excitation module respectively, changing the output power, frequency, voltage, and current waveform of the excitation power supply module, thereby providing targeted thermal excitation methods for different detection objects.

[0065] The excitation power module is configured to provide the electromagnetic excitation module with a first power source whose parameters correspond to the material and / or shape of the fitting. The first power source parameters include power level, power frequency, and loading time. The fitting material includes, but is not limited to, ferromagnetic and non-ferromagnetic materials. The fitting shape can be represented by, but not limited to, thickness or area. For ferromagnetic materials, due to their greater electromagnetic induction heat generation, the loading time can be less than 1 second, the current can be less than 200A, and the power frequency can be 100-200kHz. For non-ferromagnetic materials, the loading time can be 1-10 seconds, the current can be greater than 200A, such as 220A or 300A, and the power frequency can be greater than 200kHz, such as 300kHz. Regarding the fitting shape, based on the corresponding material parameters, the material thickness and / or area are proportional to the increased loading time; that is, the thicker the material or the larger the area, the longer the loading time. The power loading time can represent the time it takes for the electromagnetic excitation module or photothermal excitation module to heat a specific area.

[0066] The excitation power module is specifically configured to provide the photothermal excitation module with a second power supply whose parameters correspond to the first geometric parameters of the insulator. The second power supply parameters include power and loading time, while the first geometric parameters include the area or thickness of the insulator. Similarly, the area or thickness of the insulator is proportional to the power or loading time. That is, the thicker the insulator or the larger its area, the greater the power required and the longer the loading time.

[0067] The industrial computer can determine the power supply parameters according to the materials of the hardware and insulators, and control the excitation power supply module to achieve the power supply parameters.

[0068] The electromagnetic excitation module can include an electromagnetic induction coil, which can be either annular or cylindrical and can scan and heat the hardware. The electromagnetic induction coil and the hardware undergo electromagnetic induction, generating Joule heat that is not affected by the hardware surface. Defects such as cracks in the hardware can affect the heat generation, heating, and cooling processes. Compared to photothermal excitation, this provides more information by including the influence of defects during the heat generation process. In general, using electromagnetic induction to partially heat the hardware can reduce the impact of the hardware surface, provide better coupling between electromagnetic waves and the hardware, and provide information on multiple processes such as heating, heating, and cooling, providing richer defect information.

[0069] The photothermal excitation module includes one or more light sources such as halogen lamps, downlights, flashlights, or array lasers. The industrial computer can determine the light source used for heating based on the type of insulator, and turn on the light source used for heating in the photothermal excitation module to heat the insulator. The types of insulators include, but are not limited to, insulators of varying sizes or insulators coated with or without materials. The size of the insulator is proportional to the amount of array laser data. For example, if the insulator is small, the light source used for heating is a row of lasers; if the insulator is large, the light source used for heating is all lasers. For insulators coated with material, if you want to detect the state of the coating material layer, the light source used for heating is a flash lamp excitation source.

[0070] The infrared thermal imaging module includes several thermal imagers with several lenses of varying focal lengths. The industrial computer selects at least one lens to acquire first temperature change data after heating the hardware and / or second temperature change data after heating the insulator based on the second geometric parameters and accuracy of the hardware and / or insulator. "Several" refers to more than one; the second geometric parameters include volume and area; and accuracy indicates the accuracy of the temperature data sampling. Volume or area is inversely proportional to the focal length of the lens, while accuracy is directly proportional to the focal length.

[0071] In addition, the industrial computer can determine the acquisition frequency, pixel size or acquisition time of the infrared thermal imaging module according to the accuracy.

[0072] The present invention also has the following beneficial effects:

[0073] This invention addresses the different physical properties of insulator fittings and insulators, proposing adaptive heating methods tailored to the specific test objects. An electromagnetic excitation source is used to detect defects in the fittings, while a photothermal excitation source is used to detect cracks on the surface of insulators (such as porcelain components). Different thermal excitation detection methods are selected based on the material properties, improving detection accuracy and efficiency.

[0074] The present invention adopts a coil scanning electromagnetic thermal excitation loading method, combined with a data reconstruction method, to achieve single-shot, large-scale hardware defect detection, thereby improving defect detection efficiency.

[0075] In some embodiments, such as Figure 5 As shown, Figure 5 1 is a structural diagram of an electronic device provided by the present invention. The present invention also provides an electronic device, which includes a processor 10 and a memory 11, wherein the memory 11 stores a computer program, and when the processor 10 executes the computer program, it implements any one of the methods described in the above method embodiments.

[0076] Among them, the memory is a non-transient computer-readable storage medium that can be used to store non-transient software programs and non-transient computer executable programs. The memory may include a high-speed random access memory and may also include a non-transient memory, such as at least one disk storage device, a flash memory device, or other non-transient solid-state storage device. In some embodiments, the memory optionally includes a remote memory remotely arranged relative to the processor, and these remote memories can be connected to the processor via a network. Examples of the above-mentioned network include but are not limited to the Internet, an intranet, a local area network, a mobile communication network and a combination thereof.

[0077] In addition, embodiments of the present application further disclose a computer program product or computer program, which is stored in a computer-readable storage medium. A processor of a computer device can read the computer program from the computer-readable storage medium and execute the computer program, causing the computer device to perform the above-described method.

[0078] The present invention also provides a computer-readable storage medium storing a program executable by a processor. When the program is executed by the processor, it is used to execute any one of the methods described in the above method embodiments.

[0079] Similarly, the contents of the above method embodiments are applicable to the present storage medium embodiment. The functions specifically implemented by the present storage medium embodiment are the same as those of the above method embodiments, and the beneficial effects achieved are also the same as those achieved by the above method embodiments.

[0080] It will be appreciated that all or some of the steps and systems disclosed above may be implemented as software, firmware, hardware, or any suitable combination thereof. Some or all of the physical components may be implemented as software executed by a processor, such as a central processing unit, digital signal processor, or microprocessor, or as hardware, or as an integrated circuit, such as an application-specific integrated circuit. Such software may be distributed on computer-readable media, which may include computer storage media (or non-transitory media) and communication media (or transient media). As is well known to those skilled in the art, the term computer storage media includes volatile and non-volatile, removable and non-removable media implemented in any method or technology for storing information, such as computer-readable instructions, data structures, program modules, or other data. Computer storage media includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technologies, CD-ROM, digital versatile disks (DVDs) or other optical disk storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to store the desired information and can be accessed by a computer. Furthermore, as is well known to those skilled in the art, communication media typically embodies computer-readable instructions, data structures, program modules, or other data in a modulated data signal such as a carrier wave or other transport mechanism, and may include any information delivery media.

[0081] The above is a specific description of the preferred implementation of the present invention, but the invention is not limited to the embodiments. Those skilled in the art can make various equivalent modifications or substitutions without violating the spirit of the present invention. These equivalent modifications or substitutions are all included in the scope defined by the claims of this application.

Claims

1. A nondestructive detection method for insulator defects, characterized in that: The following steps are involved: Acquire first temperature change data of each pixel point after the insulator hardware is heated and second temperature change data of the insulator after the insulator is heated; Determine the maximum temperature value of each first temperature change data, and determine the shortest time of temperature drop in all first temperature change data; Shifting the time corresponding to the maximum temperature value to the same time point, and determining the reconstructed data according to the shortest time; Analyzing the characteristics of the reconstructed data at the fundamental frequency and detecting defects in the hardware according to the characteristics of the reconstructed data; analyzing the characteristics of the second temperature change data and determining defects in the insulator according to the characteristics of the second temperature change data; the characteristics of the reconstructed data include amplitude characteristics and phase characteristics; The determining of the reconstructed data according to the shortest time specifically includes: taking the same time point as the starting point, intercepting the temperature data after the maximum temperature value and within the shortest time as the reconstructed data; Analyzing the characteristics of the reconstructed data at the fundamental frequency and detecting defects of the hardware according to the characteristics of the reconstructed data specifically includes: Performing Fourier transform on the reconstructed data at a base frequency, and determining amplitude characteristics and phase characteristics of the reconstructed data according to a result of the Fourier transform; An amplitude map is reconstructed according to the amplitude characteristics and a phase map is reconstructed according to the phase characteristics, and a defect position is determined according to the amplitude map and the phase map. The size of the defect is measured according to a peak value of the defect position in the phase map.

2. A nondestructive detection system for insulator defects, characterized in that: The insulator includes a hardware and an insulator, and the nondestructive testing system includes an excitation power supply module, an electromagnetic excitation module, a photothermal excitation module, an infrared thermal imaging module, a motion module, and an industrial computer; The excitation power supply module is used to provide power to the electromagnetic excitation module and the photothermal excitation module; The electromagnetic excitation module is used to emit electromagnetic waves to generate electromagnetic induction with the hardware to heat the hardware; The photothermal excitation module is used to emit a light beam to heat the insulator; The infrared thermal imaging module is used to obtain first temperature change data of the hardware after heating and / or second temperature change data of the insulator after heating; The motion module is used to move the electromagnetic excitation module, the photothermal excitation module or the infrared thermal imaging module; The industrial computer is used to implement the method described in claim 1.

3. The system according to claim 2, characterized in that The excitation power supply module is specifically used to provide the electromagnetic excitation module with a first power supply with first power parameters corresponding to the material and / or shape of the hardware; the first power parameters include power size, power frequency and loading time.

4. The system according to claim 2, wherein: The excitation power supply module is specifically configured to provide the photothermal excitation module with a second power supply having second power supply parameters corresponding to the first geometric parameters of the insulator; the second power supply parameters include power supply power and loading time.

5. The system according to claim 2, wherein: The photothermal excitation module includes one or more light sources selected from the group consisting of a halogen lamp, a downlight, a flash lamp, and an array laser. The industrial computer is further configured to determine a light source for heating according to the type of the insulator, and to turn on the light source for heating in the photothermal excitation module to heat the insulator.

6. The system according to claim 2, wherein: The infrared thermal imaging module includes several lenses with different focal lengths; the industrial computer is also used to select at least one lens to obtain the first temperature change data of the hardware after heating and / or the second temperature change data of the insulator after heating based on the second geometric parameters and accuracy of the hardware and / or the insulator.

7. The system according to claim 2, wherein: The electromagnetic excitation module is specifically used to scan and heat the hardware.

8. An electronic device, characterized in that: The electronic device includes a memory and a processor, the memory stores a computer program, and the processor implements the method according to claim 1 when executing the computer program.

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