Partial discharge position detecting and positioning method and system

Abstract

The invention discloses a partial discharge position detecting and positioning method and system, and belongs to the technical field of partial discharge position positioning, and the method comprises the following steps: arranging sensors in a preset region, and recording a region surrounded by the sensors as a detection arrangement region; arranging a plurality of detection groups at the periphery of the detection arrangement area, wherein each detection group comprises a plurality of detection points; detecting the detection points in each detection group one by one to obtain a receiving signal; and processing the received signal, extracting an effective signal associated with the structure corrosion, and positioning the position of the effective signal. When a single detection point is detected, as a large number of ultrasonic guided waves reach the same detection point at the same time, the amplitude of the echo can be greatly enhanced, so that the problem that the amplitude of the echo is relatively weak after long-distance conduction can be effectively solved, and the influence of attenuation on the detection range is avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of partial discharge position location, and particularly relates to a method and system for detecting and locating the partial discharge position. Background Art

[0002] With the increasing demand for electricity, the scale of the power grid is constantly expanding, and power equipment is developing in the direction of large capacity and extra high voltage. In this regard, the power grid system has put forward more stringent requirements for the safe operation of power equipment and the power supply reliability.

[0003] The reliability of GIS / transformer mainly depends on the insulation state. With the wide application of insulation materials, the problem of partial discharge becomes increasingly prominent. Since the electric field is unevenly distributed, the electric field in a certain local range will be very high, and finally breakdown or electrical discharge phenomena will occur in the insulating medium. This phenomenon is called partial discharge. Partial discharge phenomena will occur between insulating layers with different dielectric characteristics, as well as in liquid insulation bubbles or solid insulation pores. By continuously corroding the surrounding insulating medium, the insulation performance of the entire equipment will be damaged eventually. Therefore, in order to ensure the stable and safe operation of GIS / transformer, it has very important practical significance to effectively detect and locate the partial discharge position.

[0004] During the process of partial discharge, there will be phenomena of power loss and charge transfer, which will cause additional noise interference. The traditional ultrasonic acoustics detects the position of partial discharge by measuring the sound generated by partial discharge. This method has problems such as being easily interfered, low detection efficiency, and poor stability. Summary of the Invention

[0005] In view of the above existing problems, the present invention is proposed.

[0006] Therefore, the technical problem solved by the present invention is that the traditional ultrasonic acoustics detects the position of partial discharge by measuring the sound generated by partial discharge, and this method has problems such as being easily interfered, low detection efficiency, and poor stability.

[0007] To solve the above technical problem, the present invention provides the following technical solution: A method for detecting and locating the partial discharge position, which includes the following steps,

[0008] Arrange sensors in a preset area, and record the area surrounded by the sensors as the detection arrangement area;

[0009] Set multiple detection groups outside the detection arrangement area, and each detection group contains multiple detection points;

[0010] Detect each detection point in each detection group one by one to obtain a received signal;

[0011] Process the received signal, extract the effective signal associated with structural corrosion, and locate the position of the effective signal.

[0012] As a preferred solution of a partial discharge position detection and location method according to the present invention, wherein: the arrangement method of the sensors includes,

[0013] A plurality of sensors are provided, and the plurality of sensors form a plurality of rings;

[0014] Among them, the radii of the plurality of rings are all different, and the plurality of rings have the same center of circle.

[0015] As a preferred solution of a partial discharge position detection and location method according to the present invention, wherein: the arrangement method of the sensors includes,

[0016] A plurality of sensors are provided, and the plurality of sensors form a cross array;

[0017] Among them, the number of sensors on the upper and lower sides of the sensor at the center of the cross array is the same, and the number of sensors on the left and right sides of the sensor at the center of the cross array is the same.

[0018] As a preferred solution of a partial discharge position detection and location method according to the present invention, wherein: the arrangement method of the sensors includes,

[0019] A plurality of sensors are provided, and the plurality of sensors form a plurality of square matrices;

[0020] Among them, the plurality of square matrices are distributed in equal proportion with the center position as the center.

[0021] As a preferred solution of a partial discharge position detection and location method according to the present invention, wherein: the setting method of the detection group includes,

[0022] The geometric center of the sensor arrangement area is denoted as the center of the circle;

[0023] The moment when the sensor emits the ultrasonic guided wave is denoted as the emission moment;

[0024] By controlling the time delay of each emission moment, the ultrasonic guided waves emitted by the plurality of sensors reach the same position simultaneously, and this position is denoted as the detection point;

[0025] The distance from the detection point to the center of the circle is denoted as the detection radius;

[0026] A plurality of detection points are arranged outside the sensor arrangement area, and the plurality of detection points with the same detection radius are denoted as a detection group;

[0027] The plurality of detection points under the jurisdiction of a single detection group are evenly distributed circumferentially around the center of the circle.

[0028] As a preferred solution of the partial discharge position detection and location method described in the present invention, among which: the step of detecting each detection point in each detection group includes,

[0029] When detecting a single detection group, perform detection operations on multiple detection points one by one;

[0030] The step of detecting a single detection point includes:

[0031] By controlling the time delay at each emission moment, make the ultrasonic guided waves emitted by multiple sensors reach the corresponding detection point simultaneously, and then after multiple sensors all receive the corresponding echo signals, continue to perform detection operations on the next detection point;

[0032] Among them, the echo signal is denoted as the received signal.

[0033] As a preferred solution of the partial discharge position detection and location method described in the present invention, among which: the location method for the position of the effective signal includes,

[0034] After receiving the received signal, process the received signal received by the sensor, eliminate the interference signals in the received signal, and obtain the effective signal related to structural corrosion;

[0035] Then use the TOF time-of-flight algorithm to process the effective signal and locate the corrosion position;

[0036] Record the corrosion position as the position of the effective signal.

[0037] Another object of the present invention is to provide a system for partial discharge position detection and location.

[0038] To solve the above technical problems, the present invention provides the following technical solution: a system for partial discharge position detection and location, including: a sensor arrangement unit, a detection control module, a signal processing module, and a positioning calculation module;

[0039] The sensor arrangement unit is used to arrange sensors in a preset area;

[0040] The detection control module is used to control the sensors to emit ultrasonic guided waves at a preset time delay;

[0041] The signal processing module is used to detect each detection point in each detection group one by one and obtain the received signal;

[0042] The positioning calculation module calculates the time difference of the received signals of each sensor and solves the corrosion position coordinates.

[0043] The present invention provides a computer device, including a memory and a processor, where the memory stores a computer program, and is characterized in that when the processor executes the computer program, the steps of a method for detecting and locating the partial discharge position are implemented.

[0044] The present invention provides a computer-readable storage medium, on which a computer program is stored, and is characterized in that when the computer program is executed by a processor, the steps of a method for detecting and locating the partial discharge position are implemented.

[0045] The beneficial effects of the present invention are as follows: When detecting a single detection point, since a large number of ultrasonic guided waves reach the same detection point simultaneously, the amplitude of the echo can be greatly enhanced, which can effectively solve the problem of weak echo amplitude after long-distance transmission, thereby avoiding the influence of attenuation on the detection range; on the other hand, due to the existence of a large number of welds in the bottom plate and various boundaries, there are a large number of interference signals caused by welds and boundaries in the echo signal. Through analysis, it is found that these interference signals are similar to the multipath effect in the radar field. The present application uses the blind signal separation algorithm commonly used in the radar field to process the signal, eliminate the interference signals in the echo, and finally obtain the effective signals related to structural corrosion. The present application uses the blind signal separation algorithm based on ICA independent component analysis to process the echo, which can better eliminate the interference signals in the echo and obtain the effective signals related to structural corrosion; finally, the TOF time-of-flight algorithm is used to process the effective signals, and the corrosion position can be located. Description of the Drawings

[0046] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0047] Figure 1 It is the overall flowchart of a method for detecting and locating the partial discharge position provided by an embodiment of the present invention.

[0048] Figure 2 It is the schematic diagram of the circular arrangement of sensors for a method for detecting and locating the partial discharge position provided by an embodiment of the present invention.

[0049] Figure 3 It is the schematic diagram of the cross-array arrangement of sensors for a method for detecting and locating the partial discharge position provided by an embodiment of the present invention.

[0050] Figure 4 It is the schematic diagram of the square matrix arrangement of sensors for a method for detecting and locating the partial discharge position provided by an embodiment of the present invention. Detailed implementation manners

[0051] To make the above objects, features, and advantages of the present invention more obvious and understandable, the following provides a detailed description of the specific implementation manners of the present invention with reference to the accompanying drawings of the specification. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0052] Embodiment 1. Refer to Figures 1 to 2 , which is the first embodiment of the present invention. This embodiment provides a method for detecting and locating the partial discharge position, including the following steps.

[0053] S1. Arrange sensors in a preset area, and record the area surrounded by the sensors as the detection and arrangement area.

[0054] In this embodiment, the arrangement method of the sensors includes

[0055] A plurality of sensors are provided, and the plurality of sensors form a plurality of rings;

[0056] Among them, the radii of the plurality of rings are all different, and the plurality of rings have the same center.

[0057] Please refer to Figure 2 As shown, a plurality of ultrasonic sensors are arranged in the middle of the bottom plate. The area surrounded by the plurality of ultrasonic sensors is recorded as the sensor arrangement area. The size of the sensor arrangement area is much smaller than the size of the bottom plate. Secondly, the transceiver integrated ultrasonic sensor is adopted. The transceiver integrated ultrasonic sensor can reduce the signal transmission path loss and reduce the influence of environmental noise (such as electromagnetic interference, mechanical vibration) on the received signal. The stray signals in the non-target area are attenuated due to lack of focusing, effectively suppressing the background noise and improving the detection rate of weak corrosion signals.

[0058] In an alternative embodiment, for example, the influence of electromagnetic interference on the received signal includes electromagnetic waves generated by motors, frequency converters, high-voltage equipment, wireless communication devices (such as Wi-Fi, Bluetooth), lightning, etc. in an industrial environment, and also includes electromagnetic radiation from the sensor's own circuit (such as the power supply module, signal processing circuit) or adjacent electronic devices. The influence on the received signal includes interference signals being superimposed on the ultrasonic signal, resulting in distortion of the echo waveform, affecting the distance measurement accuracy. A strong electromagnetic pulse may cause the sensor to misjudge the signal (such as falsely detecting a non-existent target), and high-frequency interference may drown out weak corrosion signals (such as echoes from tiny defects inside a metal structure). The sensor of this method adopts a transceiver-integrated design, which can reduce external cable connections, shorten the signal transmission path, and reduce the risk of conducted interference. The sensor housing uses metal shielding (such as grounding the bottom plate) to isolate external electromagnetic fields; in the circuit design, filtering, shielding covers, etc. are used, and an ultrasonic frequency (such as 40 kHz) that does not overlap with common industrial interference frequency bands (such as the power frequency of 50 / 60 Hz, wireless communication frequency bands) is selected to reduce co-frequency interference.

[0059] In another alternative embodiment, for example, the influence of mechanical vibration on the received signal includes equipment operation (such as pumps, fans), vehicle driving, building structure vibration, etc., and also includes the vibration of the sensor's own drive circuit or mechanical structure (such as piezoelectric ceramic elements). Among them, the influence on the received signal includes mechanical displacement of the sensor probe caused by vibration, resulting in the echo signal being superimposed with vibration noise (such as periodic fluctuations). Long-term high-frequency vibration may cause the sensor's solder joints to fall off, components to become loose, or the probe material to fatigue, and vibration may cause the ultrasonic beam direction to deviate, affecting the positioning accuracy of the target area (such as the corrosion point). This method uses a mechanical fixation method. The sensor is fixed to the middle of the bottom plate through a rigid bracket to reduce vibration conduction (the symmetry of the concentric circle arrangement enhances the structural stability), and a vibration damping material (such as a rubber pad) is added between the sensor and the bottom plate to isolate external vibration.

[0060] In this embodiment, the sensors are arranged in a circular ring layout. Detection points at different distances are covered by circular rings with different radii to achieve focused detection over a large range (such as 0.5 m to 3 m), avoiding the blind area problem of traditional single-point detection. Secondly, the multi-circular ring structure can adjust the number and distribution density of sensors according to detection requirements to adapt to GIS / transformers of different sizes. The geometric center of the sensor arrangement area coincides with the center of the bottom plate to ensure the symmetry of detection coverage and avoid positioning deviation caused by eccentricity.

[0061] Multiple concentric ring sensors form a focused sound field. Stray signals (including EMI and vibration noise) in non-target areas naturally attenuate due to lack of focusing, improving the signal-to-noise ratio. The core of the transceiver-integrated design can eliminate long-distance signal lines and reduce conductive interference; the internal circuit integration shortens the signal chain and reduces radiation interference. The integrated structure reduces mechanical connection points and lowers the risk of poor contact or structural looseness caused by vibration.

[0062] In an alternative embodiment, when applied to GIS equipment, during the detection of 110 kV GIS pipelines, internal corrosion defects of 3 mm × 2 mm were successfully located, and the detection distance reached 2.5 m; in another alternative embodiment, when applied to power transformers, during the detection of the tank wall of oil-immersed transformers, microcracks of 0.1 mm level were identified, and the false alarm rate was reduced by 60% compared with traditional ultrasonic detection.

[0063] In another group of alternative embodiments, such as in the detection of 10 kV cross-linked polyethylene (XLPE) cables in urban power grids, precise positioning of partial discharge points of underground cables was achieved. 12 transceiver-integrated ultrasonic sensors were arranged in 4 layers of concentric rings (radii 0.2 m, 0.5 m, 1.0 m, 1.5 m); 8 sensors were evenly distributed in each ring, and the total number of sensors was 96. The geometric center of the sensor arrangement area coincided with the cable axis. Using the ultrasonic signals generated by partial discharge (frequency range 100 kHz - 1 MHz), the time difference of arrival (TOA) algorithm was used to calculate the distance differences between the discharge point and each sensor, and the discharge position coordinates were determined by combining three-dimensional space geometric calculations.

[0064] Locate partial discharge points on the cable body (accuracy ±3 cm); identify surface discharges along the cable terminal head (minimum discharge amount 10 pC); distinguish corona discharge from insulation aging discharge (accuracy 95%). This embodiment demonstrates the unique advantages of the multi-ring ultrasonic sensor array in the detection of partial discharge in power cables. By optimizing the sensor configuration and positioning algorithm, precise identification and spatial positioning of discharge defects in underground concealed projects are achieved, providing a reliable basis for cable condition maintenance.

[0065] S2. Set multiple detection groups outside the detection arrangement area, and each detection group contains multiple detection points.

[0066] Denote the geometric center of the sensor arrangement area as the center of the circle;

[0067] Denote the moment when the sensor emits ultrasonic guided waves as the emission moment;

[0068] By controlling the time delay of each emission moment, make the ultrasonic guided waves emitted by multiple sensors reach the same position simultaneously, and this position is denoted as the detection point;

[0069] Denote the distance from the detection point to the center of the circle as the detection radius;

[0070] A plurality of detection points are arranged outside the sensor arrangement area, and a plurality of detection points with the same detection radius are recorded as a detection group;

[0071] The multiple detection points under the jurisdiction of a single detection group are evenly distributed circumferentially along the center of the circle.

[0072] Among them, the detection points are evenly distributed along the center of the circle (such as one point every 60°), ensuring 360° blind - area - free coverage, avoiding the directional limitation of traditional single - point detection, and multiple detection points within the same detection group provide multiple sets of TOF time differences. Based on the hyperbola positioning principle, the theoretical error ≤ 5mm, and multiple detection points cross - verify to reduce misjudgment caused by single - sensor failure.

[0073] In an alternative embodiment, for example, for partial discharge detection of GIS pipelines, the sensors are arranged in 3 concentric circles with radii of 0.5m, 1.0m, and 1.5m respectively, and there are 8 sensors in each layer (24 in total); the detection radius range is 2.0m - 3.0m, with an interval of 0.3m (4 detection groups in total), and each detection group contains 6 detection points (the central angle interval is 60°); the ultrasonic guided - wave parameters are: the center frequency is 100kHz, and the pulse width is 2μs.

[0074] Successfully locate a 3mm×2mm corrosion defect at a distance of 2.5m, with a positioning error ≤ 4mm; the detection time: it takes 12 seconds to complete 1 detection group (6 points), and the total detection time is 2 minutes; anti - interference: in a 50Hz power - frequency interference environment, the effective signal recognition rate reaches 98%. This embodiment and the traditional single - point detection require manual movement of the sensor, and it takes 15 minutes to complete the detection of the same area, with a positioning error of 8 - 12mm.

[0075] In another group of alternative embodiments, for example, for corrosion detection of the wall of a power transformer tank, the sensors are arranged in 2 concentric circles with radii of 0.8m and 1.6m, and there are 12 sensors in each layer (24 in total); the detection radius range is 2.0m - 3.5m, with an interval of 0.5m (4 detection groups in total), and each detection group contains 8 detection points (the central angle interval is 45°), and the ultrasonic guided - wave parameters are: the center frequency is 200kHz, frequency - modulated continuous wave (FMCW).

[0076] Detect a 0.1mm - level micro - crack, with a positioning error ≤ 3mm; the time taken for a single detection group is 8 seconds, and the total detection time is 1.5 minutes; in an oil - immersed environment, the effective signal strength is increased by 15dB compared with the traditional method. In this embodiment, compared with traditional ultrasonic detection that requires a coupling agent, the detection speed is slow (it takes 20 minutes for the same area), and the detection rate of micro - cracks is less than 70%.

[0077] S3. Detect each detection point within each detection group one by one to obtain the received signal.

[0078] The steps of detecting each detection point in each detection group include

[0079] When detecting a single detection group, perform detection operations on multiple detection points one by one;

[0080] The steps of detecting a single detection point include:

[0081] By controlling the time delay at each emission moment, make the ultrasonic guided waves emitted by multiple sensors reach the corresponding detection point simultaneously, improve the defect detection rate, and then continue to perform detection operations on the next detection point after multiple sensors have received the corresponding echo signals;

[0082] This step can significantly improve the signal-to-noise ratio (SNR) of the received signal. For example, in weld detection, the amplitude of the crack echo can be increased by more than 30%. Secondly, by detecting each detection point one by one, ensure that the acoustic energy is concentrated at each position, and avoid energy dispersion caused by detecting multiple points simultaneously. For example, in the application of pipelines, circumferential uniform scanning of the curved surface structure can achieve 100% coverage. Finally, because when detecting a single detection point, the sensors at other detection points are in a silent state, reducing the superimposed interference of multipath reflection and environmental noise.

[0083] In an optional embodiment, such as partial discharge detection of GIS pipelines, the detection radius range is 1.5m - 2.5m (outer surface of the pipeline), with an interval of 0.2m (a total of 6 detection groups), and each group contains 6 detection points (central angle 60°). For each group of detection points, trigger the sensors to emit guided waves in sequence: calculate the distance from each sensor to the current detection point, use the ICA algorithm to separate the effective signals (amplitude > 50mV), and identify corrosion defects. For example, when using traditional single-point detection, the pipeline needs to be disassembled, the detection time is 4 hours, and the positioning error is 8 - 12mm.

[0084] Among them, the echo signal is recorded as the received signal.

[0085] S4. Process the received signal, extract the effective signals associated with structural corrosion, and locate the positions of the effective signals.

[0086] The positioning method for the position of the effective signal includes

[0087] After receiving the received signal, process the received signal received by the sensor, remove the interference signals in the received signal, and obtain the effective signals related to structural corrosion;

[0088] Then use the TOF time-of-flight algorithm to process the effective signals and locate the corrosion positions;

[0089] Record the corrosion positions as the positions of the effective signals.

[0090] When processing the received signal by the sensor, the present application uses a blind signal separation algorithm based on ICA (Independent Component Analysis) to process the echo, which can better remove the interference signals in the echo and obtain the effective signals related to structural corrosion; finally, the TOF (Time of Flight) algorithm is used to process the effective signals, and the corrosion location can be located.

[0091] In this embodiment, it is assumed that the mixed signal X(t) = As(t), and the independent components s(t) are separated by maximizing non-Gaussianity;

[0092] Actually, whitening processing is used: z(t) = WX(t), W = (ED -1 / 2 E T ) -1 ; where E is the eigenvector matrix and D is the eigenvalue of the covariance matrix;

[0093] Then, the separation matrix W is initialized and updated iteratively until convergence. Calculate the kurtosis of each independent component, and select the component with the maximum kurtosis (the corrosion signal has higher non-Gaussianity).

[0094] In an alternative embodiment, in addition to the blind signal separation algorithm based on ICA, the wavelet transform algorithm can also be used. It performs 5-layer decomposition of the received signal using db4 wavelet, and performs hard threshold denoising on the high-frequency coefficients. After reconstructing the signal, the characteristic frequency band related to corrosion is extracted (such as 50 - 100 kHz); a uniform circular array (6 sensors, radius 0.5 m) is adopted. The MUSIC algorithm estimates the signal incident angle, and combines with the geometric formula to calculate the position coordinates. The AOA positioning formula involved in this embodiment is expressed as:

[0095]

[0096] where c is the wave speed, is the time difference corresponding to the phase difference between adjacent array elements, and r is the array element radius.

[0097] In another alternative embodiment, in addition to using the wavelet transform algorithm, the power frequency interference can also be suppressed by using the ambient noise as the reference input and the LMS filter, and the signal is further purified by using band-pass filtering (30 - 150 kHz). Among them, the positioning method adopted is to collect the signal intensities of 50 standard points offline to construct a fingerprint database. When matching online, the signal attenuation model used is to take the weighted average of the 3 nearest neighbor fingerprint points for positioning, and the signal attenuation model used is expressed as:

[0098]

[0099] where P(d) is the signal intensity at the reference distance d0, n is the path loss exponent, and X δ is Gaussian noise.

[0100] In summary, when detecting a single detection point, since a large number of ultrasonic guided waves arrive at the same detection point simultaneously, the amplitude of the echo can be greatly enhanced, which can effectively solve the problem of weak echo amplitude after long-distance transmission, thereby avoiding the influence of attenuation on the detection range. On the other hand, due to the existence of a large number of welds in the bottom plate and various boundaries, there are a large number of interference signals caused by welds and boundaries in the echo signal. After analysis, it is found that these interference signals are similar to the multipath effect in the radar field. The present application uses the blind signal separation algorithm commonly used in the radar field to process the signal and eliminate the interference signals in the echo. Finally, an effective signal related to structural corrosion can be obtained. The present application uses the blind signal separation algorithm based on ICA independent component analysis to process the echo, which can better eliminate the interference signals in the echo and obtain an effective signal related to structural corrosion. Finally, the TOF time-of-flight algorithm is used to process the effective signal, and the corrosion location can be located.

[0101] Embodiment 2 is the second embodiment of the present invention, which is different from the previous embodiment in that:

[0102] Please refer to Figure 3 As shown, in this embodiment, the arrangement method of the sensors includes

[0103] A plurality of sensors are provided, and the plurality of sensors form a cross array;

[0104] Among them, the number of sensors on the upper and lower sides of the sensor at the center of the cross array is the same, and the number of sensors on the left and right sides of the sensor at the center of the cross array is the same.

[0105] In this embodiment, the cross array arrangement method is adopted, and the orthogonal symmetric structure of the cross array can achieve 360° blind area-free monitoring, especially suitable for axially symmetric structures such as GIS equipment cylinders or transformer windings. Each sensor forms a specific angle (such as 0°, 90°, 180°, 270°) with the central sensor, and the calculation accuracy of the time difference of arrival (TOA) of the signal is improved through the triangulation principle.

[0106] And each detection point can be received by more than 4 groups of sensors simultaneously (such as the central sensor + four-direction sensors), and the signal-to-noise ratio is improved through signal superposition. The effective signal strength S = Σ(Si * cosθi), where θi is the angle between the i-th sensor and the signal source. Redundant reception can suppress random noise N and increase S / N by √n times (n is the number of sensors). The geometric symmetry of the cross array makes the positioning equation have a decoupling characteristic, simplifying the calculation complexity of the TOF algorithm. The cross array can simultaneously excite guided waves in multiple directions, and the single detection coverage area is π times that of the linear array; for transformer winding detection, the detection time can be shortened from the traditional point-by-point scanning of 30 minutes to within 5 minutes.

[0107] All other steps are the same as those in Embodiment 1.

[0108] Embodiment 3 is the third embodiment of the present invention. What is different from the previous two embodiments is:

[0109] Please refer to Figure 4 As shown, in this embodiment, the arrangement method of the sensors includes

[0110] A plurality of sensors are provided, and the plurality of sensors form a plurality of square matrices;

[0111] Among them, the plurality of square matrices are distributed in equal proportion with the most central position as the center.

[0112] In this embodiment, the sensors are constructed by using the distribution method of square matrices. The square matrices are expanded in equal proportion with the center as the reference (for example, the side lengths increase in the ratio of 1:2:3), so as to realize hierarchical detection from the near field to the far field.

[0113] The coverage area is increased compared with the concentric circle array, and the calculation formula is: S = n 2 ·a 2 , in this formula, n is the number of matrix layers, and a is the side length of the smallest matrix. The sensor spacing inside each matrix is equal (such as 0.2 m), ensuring that the far-field detection points still maintain a high spatial resolution (such as defect identification at the 1 mm level).

[0114] Moreover, the orthogonal structure of the square matrix focuses the ultrasonic guided waves in the X / Y axis directions, increasing the signal amplitude by 20 - 30 dB compared with random arrangement. In the detection of GIS pipelines, the amplitude of the corrosion echo at 1.5 m reaches 150 mV, which is 12 dB higher than that of the traditional method. The stray signals in the non-target area are attenuated because they are not aligned with the matrix direction, effectively suppressing environmental noise (such as mechanical vibration). Additionally, each detection point is covered by more than 4 groups of sensors, and the single-sensor error (such as temperature drift) is eliminated through cross-positioning. The number of matrix layers can be dynamically adjusted according to the equipment size (such as 3 layers for the transformer tank wall and 5 layers for GIS pipelines), reducing the design complexity. The square matrix supports parallel detection (such as simultaneously exciting the sensors on the four sides), saving 40% - 60% of the time compared with point-by-point scanning.

[0115] Embodiment 4 is the fourth embodiment of the present invention. What is different from the previous three embodiments is:

[0116] If the above-described functions are implemented in the form of software function units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in various embodiments of the present invention. The foregoing storage medium includes: various media that can store program codes, such as USB flash drives, mobile hard disks, read-only memories (ROMs), random access memories (RAMs), magnetic disks, or optical discs.

[0117] The logic and / or steps represented in the flowchart or described in other ways herein, for example, can be considered as a definite sequence list of executable instructions for implementing logical functions, and can be specifically implemented in any computer-readable medium for use by an instruction execution system, apparatus, or device (such as a computer-based system, a system including a processor, or other systems that can fetch and execute instructions from the instruction execution system, apparatus, or device), or in combination with these instruction execution systems, apparatuses, or devices. For the purposes of this specification, a "computer-readable medium" can be any device that can contain, store, communicate, propagate, or transport a program for use by or in connection with an instruction execution system, apparatus, or device.

[0118] More specific examples (non-exhaustive list) of computer-readable media include the following: electrical connection parts with one or more wirings (electronic devices), portable computer disk cartridges (magnetic devices), random access memories (RAMs), read-only memories (ROMs), erasable programmable read-only memories (EPROMs or flash memories), optical fiber devices, and portable compact disc read-only memories (CDROMs). Additionally, the computer-readable medium can even be paper or other suitable media on which the program can be printed, because the program can be obtained electronically, for example, by optically scanning the paper or other media, then editing, interpreting, or processing it in other suitable ways as necessary, and then storing it in a computer memory.

[0119] It should be understood that each part of the present invention can be implemented by hardware, software, firmware or a combination thereof. In the above embodiments, multiple steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, any one or a combination of the following techniques well known in the art can be used: discrete logic circuits having logic gate circuits for implementing logic functions on data signals, application specific integrated circuits having appropriate combinational logic gate circuits, programmable gate arrays (PGAs), field programmable gate arrays (FPGAs), etc.

[0120] Embodiment 5 is the fifth embodiment of the present invention. This embodiment provides a system for detecting and locating the partial discharge position, including a sensor arrangement unit, a detection control module, a signal processing module, and a positioning calculation module.

[0121] The sensor arrangement unit is used to arrange sensors in a preset area.

[0122] The detection control module is used to control the sensors to emit ultrasonic guided waves according to a preset time delay.

[0123] The signal processing module is used to detect each detection point in each detection group one by one to obtain received signals.

[0124] The positioning calculation module calculates the time difference of the received signals of each sensor and solves the coordinates of the corrosion position.

[0125] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the spirit and scope of the technical solutions of the present invention, and they should all be covered within the scope of the claims of the present invention.

Claims

1. A method for detecting and locating the partial discharge position, characterized in that: Including the following steps, Arrange sensors in a preset area, and record the area surrounded by the sensors as the detection arrangement area; Set multiple detection groups outside the detection arrangement area, and each detection group includes multiple detection points; Detect each detection point in each detection group one by one to obtain received signals; Process the received signals, extract the effective signals associated with structural corrosion, and locate the positions of the effective signals.

2. The partial discharge position detection and location method according to claim 1, characterized in that: The arrangement method of the sensors includes, A plurality of sensors are provided, and the plurality of sensors form a plurality of rings; Among them, the radii of the plurality of rings are all different, and the plurality of rings have the same center.

3. The partial discharge position detection and location method according to claim 1, characterized in that: The arrangement method of the sensors includes, A plurality of sensors are provided, and the plurality of sensors form a cross array; Among them, the number of sensors on the upper and lower sides of the sensor at the center of the cross array is the same, and the number of sensors on the left and right sides of the sensor at the center of the cross array is the same.

4. A method for detecting and locating the partial discharge position according to claim 1, characterized in that: The arrangement method of the sensors includes, A plurality of sensors are provided, and the plurality of sensors form a plurality of square matrices; Among them, the plurality of square matrices are equally proportionally distributed with the center position as the center.

5. A method for detecting and locating the partial discharge position according to any one of claims 2 to 4, characterized in that: The setting method of the detection group includes, Record the geometric center of the sensor arrangement area as the center of the circle; Record the moment when the sensor emits ultrasonic guided waves as the emission moment; By controlling the time delay of each emission moment, make the ultrasonic guided waves emitted by a plurality of sensors reach the same position simultaneously, and this position is recorded as the detection point; Record the distance from the detection point to the center of the circle as the detection radius; Set a plurality of detection points outside the sensor arrangement area, and a plurality of detection points with the same detection radius are recorded as one detection group; The plurality of detection points under the jurisdiction of a single detection group are evenly distributed along the circumferential direction of the center of the circle.

6. The partial discharge position detection and location method according to claim 5, characterized in that: The step of detecting each detection point in each detection group one by one includes, When detecting a single detection group, perform detection operations on each of the plurality of detection points one by one; The step of detecting a single detection point includes: By controlling the time delay of each emission moment, make the ultrasonic guided waves emitted by a plurality of sensors reach the corresponding detection point simultaneously, and then after each of the plurality of sensors receives the corresponding echo signal, continue to perform detection operations on the next detection point; Among them, the echo signal is recorded as the received signal.

7. The partial discharge position detection and location method according to claim 6, characterized in that: The positioning method of the position of the effective signal includes, After receiving the received signal, process the received signal received by the sensor, remove the interference signal in the received signal, and obtain the effective signal related to structural corrosion; Then use the TOF time-of-flight algorithm to process the effective signal and locate the corrosion position; Record the corrosion position as the position of the effective signal.

8. A system for detecting and locating the partial discharge position, which applies a method for detecting and locating the partial discharge position according to any one of claims 1 to 7, characterized in that, Including: A sensor arrangement unit, a detection control module, a signal processing module, and a positioning calculation module; The sensor arrangement unit is used to arrange sensors in a preset area; The detection control module is used to control the sensors to emit ultrasonic guided waves at a preset time delay; The signal processing module is used to detect each detection point in each detection group one by one to obtain received signals; The positioning calculation module calculates the time difference of the received signals of each sensor and solves the corrosion position coordinates.

9. A computer device, comprising a memory and a processor, the memory storing a computer program, characterized in that, When the processor executes the computer program, it implements the steps of a partial discharge position detection and positioning method according to any one of claims 1 to 7.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, the steps of a partial discharge position detection and location method according to any one of claims 1 to 7 are implemented.

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