Visual detection method and system for partial discharge in power construction

Abstract

The invention relates to the field of discharge fault detection, in particular to a power construction partial discharge visual detection method and system, and the method comprises the steps: carrying out the ultrasonic collection and thermal infrared detection of a power construction region, and obtaining the ultrasonic signal data and thermal infrared signal data of the power construction region; based on the ultrasonic signal data, partial discharge fault point distribution of the power construction area is determined; based on the thermal infrared signal data, determining ultrasonic thermal effect characteristics in a range adjacent to the partial discharge fault point; based on the ultrasonic heat effect characteristics, estimating deviation information of partial discharge fault point distribution; and based on the infrared absorption spectrum data of the power construction area, correcting the deviation information to obtain a partial discharge fault visual distribution map of the power construction area. According to the method, the defect that the detected ultrasonic intensity spatial distribution cannot accurately and truly represent the original condition of partial discharge due to the ultrasonic heat effect can be overcome, and the detection deviation of the partial discharge position is corrected.

Description

Technical Field

[0001] The present invention relates to the field of discharge fault detection, and in particular to a method and system for visually detecting partial discharge in electric power construction. Background Art

[0002] The construction of electric power projects is huge, involving a large number of electrical equipment and complex wires and pipelines. When the construction operation is improper or the insulation is aged and damaged, partial discharge and other faults will occur. When partial discharge occurs, electrical equipment or wires and pipelines will emit high voltage electricity, which will stimulate the generation of substances such as ultrasonic waves during the release of high voltage electricity. Considering that ultrasonic waves have good directionality, strong penetration, and concentrated energy that is not easy to dissipate during transmission, ultrasonic detection of electrical equipment or wires and pipelines is an important means of detecting partial discharge in existing technologies. By detecting the spatial distribution of ultrasonic intensity, the location of partial discharge can be accurately determined, and visual detection of partial discharge can be achieved.

[0003] As can be seen from the above, partial discharge visualization detection is achieved by detecting the intensity of ultrasonic waves, and the ultrasonic thermal effect will seriously affect the accuracy of partial discharge detection. When ultrasonic waves pass through an object, the object will absorb the ultrasonic energy and convert it into heat energy, and the intensity of the ultrasonic wave itself will decrease; the greater the intensity of the ultrasonic wave itself, the more significant its thermal effect. When the intensity of partial discharge is large, the intensity attenuation of the accompanying ultrasonic wave due to the thermal effect during the transmission process is also greater, resulting in the inability of the directly detected spatial distribution of the ultrasonic wave intensity to accurately characterize the location of partial discharge. It can be seen that how to identify the partial discharge position detection deviation caused by the thermal effect of the ultrasonic wave generated by the partial discharge and correct the partial discharge position detection deviation is of great significance for accurately locating partial discharge faults and realizing the visualization detection of partial discharge faults. Summary of the invention

[0004] Considering that the ultrasonic thermal effect causes the ultrasonic intensity to be significantly attenuated, the detected ultrasonic intensity spatial distribution cannot accurately and truly represent the original situation of partial discharge, resulting in deviations in the partial discharge position located by ultrasonic detection. It is necessary to correct the deviation in the partial discharge position in combination with the state of gas substances generated by the detection of partial discharge, so as to achieve full-range and high-precision partial discharge positioning in the power construction area. The present invention provides a method for visual detection of partial discharge in power construction, which comprises the following steps: Performing ultrasonic collection and thermal infrared detection on the power construction area to obtain ultrasonic signal data and thermal infrared signal data of the power construction area; determining the distribution of partial discharge fault points in the power construction area based on the ultrasonic signal data; Based on the thermal infrared signal data, determining the ultrasonic thermal effect characteristics of the vicinity of the partial discharge fault point; based on the ultrasonic thermal effect characteristics, estimating the deviation information of the distribution of the partial discharge fault point; Based on the infrared absorption spectrum data of the power construction area, the deviation information is corrected to obtain a visualized distribution map of partial discharge faults in the power construction area.

[0005] Preferably, the ultrasonic collection and thermal infrared detection are performed on the power construction area to obtain the ultrasonic signal data and thermal infrared signal data of the power construction area, specifically: Performing global ultrasonic scanning and acquisition on the power construction area to obtain the time domain recurrence characteristics of the ultrasonic intensity change in the power construction area in several scanning cycles; based on the time domain recurrence characteristics of the ultrasonic intensity change, identifying the suspected discharge electron area in the power construction area; Directional continuous ultrasonic collection and thermal infrared detection are performed on the suspected electron-discharging area to obtain ultrasonic signal data and thermal infrared signal data of the suspected electron-discharging area; wherein the ultrasonic signal data includes time-domain continuous data on the spatial distribution of ultrasonic intensity of the suspected electron-discharging area; and the thermal infrared signal data includes time-domain continuous data on the spatial distribution of thermal infrared radiation intensity of all objects in the suspected electron-discharging area.

[0006] Preferably, the determining of the distribution of partial discharge fault points in the power construction area based on the ultrasonic signal data is specifically as follows: Performing spatiotemporal frame processing on the time-domain continuous data of the ultrasonic intensity spatial distribution of the suspected electron-discharging region to obtain a number of ultrasonic intensity spatial distribution data frames of the suspected electron-discharging region; performing ultrasonic beam edge recognition and time-domain inversion on the several ultrasonic intensity spatial distribution data frames to obtain the ultrasonic beam transmission path inside the suspected electron-discharging region; The ultrasonic beam transmission path is spatially traced to obtain the distribution of local discharge fault points inside the suspected sub-discharge area; wherein the local discharge fault point distribution includes the spatial occupation range of the local discharge fault points inside the suspected sub-discharge area.

[0007] Preferably, the ultrasonic thermal effect characteristics of the vicinity of the partial discharge fault point are determined based on the thermal infrared signal data; and the deviation information of the distribution of the partial discharge fault point is estimated based on the ultrasonic thermal effect characteristics, specifically: Based on the distribution of the partial discharge fault points, calibrate the contour features of the objects adjacent to the partial discharge fault points; based on the contour features, extract the thermal infrared signal sub-data of the adjacent objects from the thermal infrared signal data; Perform heat accumulation positioning analysis on the thermal infrared signal sub-data to determine the site boundary of the local discharge fault point where the ultrasonic thermal effect occurs in the object adjacent to the local discharge fault point; based on the site boundary and the spatial occupation range of the local discharge fault point, estimate the fault point with incorrect positioning in the local discharge fault point distribution and its positioning deviation.

[0008] Preferably, the deviation information is corrected based on the infrared absorption spectrum data of the power construction area to obtain a visualized distribution map of partial discharge faults in the power construction area, specifically: Analyze the infrared absorption spectrum data of the distribution range of the local discharge fault points in the power construction area to obtain the preset gas space movement characteristics of the distribution range of the local discharge fault points; based on the preset gas space movement characteristics, correct the positioning deviation of the fault points that are mislocated in the distribution of the local discharge fault points; Based on the corrected partial discharge fault point distribution, the fault point density and fault point discharge intensity are calculated to determine the high-voltage electrical breakdown sub-area distribution information of the power construction area, thereby generating a visualized distribution map of partial discharge faults in the power construction area.

[0009] On the other hand, the present invention provides a visual detection system for partial discharge in power construction, the system comprising the following modules: An ultrasonic acquisition module is used to perform ultrasonic acquisition on the electric power construction area to obtain ultrasonic signal data of the electric power construction area; A thermal infrared detection module is used to perform thermal infrared detection on the power construction area to obtain thermal infrared signal data of the power construction area; A partial discharge fault point determination module, used to determine the distribution of partial discharge fault points in the power construction area based on the ultrasonic signal data; A fault point distribution deviation estimation module is used to determine the ultrasonic thermal effect characteristics of the vicinity of the partial discharge fault point based on the thermal infrared signal data; and estimate the deviation information of the partial discharge fault point distribution based on the ultrasonic thermal effect characteristics; A deviation correction module, used for correcting the deviation information based on the infrared absorption spectrum data of the power construction area; The visualization map generation module is used to generate a visualization distribution map of partial discharge faults in the power construction area.

[0010] Preferably, before the ultrasonic acquisition module performs ultrasonic acquisition on the power construction area, it also includes: Performing global ultrasonic scanning and acquisition on the power construction area to obtain the time domain recurrence characteristics of the ultrasonic intensity change in the power construction area in several scanning cycles; based on the time domain recurrence characteristics of the ultrasonic intensity change, identifying the suspected discharge electron area in the power construction area; The ultrasonic acquisition module is used to perform ultrasonic acquisition on the power construction area to obtain ultrasonic signal data of the power construction area, specifically: Directed continuous ultrasonic acquisition is performed on the suspected electron-discharging region to obtain ultrasonic signal data of the suspected electron-discharging region; wherein the ultrasonic signal data includes time-domain continuous data of the spatial distribution of ultrasonic intensity of the suspected electron-discharging region; The thermal infrared detection module is used to perform thermal infrared detection on the power construction area to obtain thermal infrared signal data of the power construction area, specifically: Thermal infrared detection is performed on the suspected electron-discharging area to obtain thermal infrared signal data of the suspected electron-discharging area; wherein the thermal infrared signal data includes time-domain continuous data of the spatial distribution of thermal infrared radiation intensity of all objects in the suspected electron-discharging area.

[0011] Preferably, the local discharge fault point determination module is used to determine the distribution of local discharge fault points in the power construction area based on the ultrasonic signal data, specifically: Performing spatiotemporal frame processing on the time-domain continuous data of the ultrasonic intensity spatial distribution of the suspected electron-discharging region to obtain a number of ultrasonic intensity spatial distribution data frames of the suspected electron-discharging region; performing ultrasonic beam edge recognition and time-domain inversion on the several ultrasonic intensity spatial distribution data frames to obtain the ultrasonic beam transmission path inside the suspected electron-discharging region; The ultrasonic beam transmission path is spatially traced to obtain the distribution of local discharge fault points inside the suspected sub-discharge area; wherein the local discharge fault point distribution includes the spatial occupation range of the local discharge fault points inside the suspected sub-discharge area.

[0012] Preferably, the fault point distribution deviation estimation module is used to determine the ultrasonic thermal effect characteristics of the vicinity of the partial discharge fault point based on the thermal infrared signal data; based on the ultrasonic thermal effect characteristics, estimate the deviation information of the partial discharge fault point distribution, specifically: Based on the distribution of the partial discharge fault points, calibrate the contour features of the objects adjacent to the partial discharge fault points; based on the contour features, extract the thermal infrared signal sub-data of the adjacent objects from the thermal infrared signal data; Perform heat accumulation positioning analysis on the thermal infrared signal sub-data to determine the site boundary of the local discharge fault point where the ultrasonic thermal effect occurs in the object adjacent to the local discharge fault point; based on the site boundary and the spatial occupation range of the local discharge fault point, estimate the fault point with incorrect positioning in the local discharge fault point distribution and its positioning deviation.

[0013] Preferably, the deviation correction module is used to correct the deviation information based on the infrared absorption spectrum data of the power construction area, specifically: Analyze the infrared absorption spectrum data of the distribution range of the local discharge fault points in the power construction area to obtain the preset gas space movement characteristics of the distribution range of the local discharge fault points; based on the preset gas space movement characteristics, correct the positioning deviation of the fault points that are mislocated in the distribution of the local discharge fault points; The visualization map generation module is used to generate a visualization distribution map of partial discharge faults in the power construction area, specifically: Based on the corrected partial discharge fault point distribution, the fault point density and fault point discharge intensity are calculated to determine the high-voltage electrical breakdown sub-area distribution information of the power construction area, thereby generating a visualized distribution map of partial discharge faults in the power construction area.

[0014] Compared with the prior art, the present invention has the following beneficial effects: Ultrasonic acquisition and thermal infrared detection are performed on the power construction area to obtain ultrasonic signal data and thermal infrared signal data of the power construction area; based on the ultrasonic signal data, the distribution of local discharge fault points in the power construction area is determined. In the process of preliminary detection of the power construction area, a global ultrasonic scanning and acquisition is first performed on the power construction area to identify the suspected discharge electron area in the power construction area, which can effectively narrow the visual detection range of local discharge, reduce the workload of full-range inspection of the power construction area, and accurately locate the local discharge in the early stage. The ultrasonic signal data and thermal infrared signal data comprehensively characterize the ultrasonic intensity distribution state generated by the local discharge in the suspected discharge electron area and the thermal infrared radiation intensity distribution state formed after the object receives the ultrasonic wave, providing reliable data for the subsequent comprehensive characterization of the local discharge fault point location and the deviation of the fault point location in the suspected discharge area.

[0015] Based on the thermal infrared signal data, the ultrasonic thermal effect characteristics of the vicinity of the local discharge fault point are determined; based on the ultrasonic thermal effect characteristics, the deviation information of the distribution of the local discharge fault point is estimated. The intensity of the ultrasonic wave will decay after passing through the object due to the thermal effect, so that the edge boundary of the ultrasonic wave energy in the space will shrink accordingly, resulting in a corresponding deviation in the position of the local discharge fault point determined by the ultrasonic wave detected by the ultrasonic sensor array. By determining the range of the part of the object passed by the ultrasonic wave, the process of the ultrasonic thermal effect on the object and its influence on the positioning deviation of the local discharge fault point can be determined, which is convenient for the subsequent accurate position correction of the local discharge fault point distribution obtained according to the ultrasonic signal data.

[0016] Based on the infrared absorption spectrum data of the power construction area, the deviation information is corrected to obtain a visualization distribution map of partial discharge faults in the power construction area. The high voltage electricity released during the partial discharge in the power construction area will break through the air and generate specific types of gases. By detecting the propagation and diffusion of these specific types of gases to obtain the diffusion and propagation source of the gas, the location of the partial discharge that produces these specific types of gases can be accurately determined. By detecting the infrared absorption peak of the air in the distribution range of the partial discharge fault point, the specific location of these specific types of gases in the distribution range of the partial discharge fault point can be determined, so that the position deviation of the above-mentioned partial discharge fault point can be corrected within a smaller spatial range. In addition, based on the distribution information of the high-voltage electricity breakdown sub-area in the power construction area, a visualization distribution map of partial discharge faults in the power construction area is generated, which can visualize the partial discharge faults in the entire range of the power construction area and realize the full range and high-precision partial discharge positioning of the power construction area. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. Among them: Figure 1 The present invention provides a flow chart of a method for visually detecting partial discharge in power construction.

[0018] Figure 2 It is the time-frequency diagram corresponding to the change of ultrasonic intensity in the suspected electron discharge area.

[0019] Figure 3 It is the spatial distribution diagram of the ultrasonic intensity in the suspected electron discharge area.

[0020] Figure 4 It is a structural diagram of a visual detection system for partial discharge in electric power construction provided by the present invention. DETAILED DESCRIPTION

[0021] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings. It is understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only the parts related to the present invention rather than all structures are shown in the accompanying drawings. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0022] The terms "including" and "having" and any variations thereof in the present invention are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device comprising a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products or devices.

[0023] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present invention. The appearance of the phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0024] See also Figure 1 As shown, the present invention provides a method for visually detecting partial discharge in power construction, the method comprising the following steps: S100, performing ultrasonic collection and thermal infrared detection on the power construction area to obtain ultrasonic signal data and thermal infrared signal data of the power construction area; based on the ultrasonic signal data, determining the distribution of local discharge fault points in the power construction area.

[0025] Furthermore, ultrasonic collection and thermal infrared detection are performed on the power construction area to obtain ultrasonic signal data and thermal infrared signal data of the power construction area, specifically: Perform global ultrasonic scanning and acquisition of the power construction area to obtain the time domain recurrence characteristics of the ultrasonic intensity change in the power construction area in several scanning cycles; based on the time domain recurrence characteristics of the ultrasonic intensity change, identify the suspected discharge electron area in the power construction area; Directed continuous ultrasonic collection and thermal infrared detection are carried out on the suspected electron-discharging area to obtain ultrasonic signal data and thermal infrared signal data of the suspected electron-discharging area; wherein the ultrasonic signal data include the spatial distribution and time-domain continuous data of the ultrasonic intensity of the suspected electron-discharging area; and the thermal infrared signal data include the spatial distribution and time-domain continuous data of the thermal infrared radiation intensity of all objects in the suspected electron-discharging area.

[0026] The internal space of power construction areas such as power stations and substations is vast, the number of power equipment is large, and the layout of power pipelines is complicated, making the environment of power construction areas complex. When a partial discharge fault occurs in the power construction area due to human construction errors or aging of equipment lines, the location of the partial discharge fault may be relatively hidden, and in the initial stage of partial discharge, it will not cause visible phenomena such as sparks or smoke. In order to conduct timely and full-range detection of early partial discharge faults in the power construction area, robots can be used to enter the internal inspection of the power construction area. During the inspection, the robot will simultaneously perform ultrasonic collection and thermal infrared detection in the power construction area to realize automated detection of the power construction area. Considering the large internal space of the power construction area, it takes a long time for the robot to complete a complete inspection of the internal space of the power construction area, which is not conducive to timely discovery of partial discharge faults in the power construction area and cannot efficiently detect the power construction area. Under normal circumstances, the ultrasonic signal content in the internal space of the power construction area can be ignored. Once a partial discharge occurs in a sub-area of ​​the internal space of the power construction area, ultrasonic waves will be generated during the release of high voltage electricity by the partial discharge, and the ultrasonic wave intensity is positively correlated with the partial discharge intensity. In addition, the ultrasonic waves generated by the partial discharge will remain in the environment for a period of time. Regardless of the duration of the partial discharge itself, once a partial discharge occurs, a corresponding ultrasonic signal will inevitably be formed in the environment. Based on the above relationship between partial discharge and ultrasonic wave generation, during the initial detection stage of the robot in the power construction area, as long as the entire range of the power construction area is scanned and collected, the residual ultrasonic wave in the internal space of the power construction area can be determined.

[0027] Specifically, the robot's built-in ultrasonic sensor array can be used to perform several global ultrasonic scans and acquisitions on the power construction area. During each global ultrasonic scan and acquisition process, the ultrasonic sensor array will completely scan and detect the ultrasonic intensity distribution information of the entire power construction area within the corresponding scanning cycle duration; the ultrasonic intensity distribution information obtained within several scanning cycle durations will be compared in time domain to obtain the time domain reproduction characteristics of the ultrasonic intensity changes in the power construction area during several scanning cycles; the above-mentioned time domain reproduction characteristics of the ultrasonic intensity changes refer to the temporal repetition characteristics of the ultrasonic intensity increase to decrease events in each sub-area within the entire power construction area. If the number of times that the ultrasonic intensity increases and decreases in a certain sub-region of the power construction area on the surface of the above-mentioned ultrasonic intensity change time domain repetition feature is greater than or equal to the preset number threshold, it indicates that the above-mentioned sub-region may periodically undergo local discharge accompanied by periodic formation of ultrasonic waves, and the above-mentioned sub-region is determined as a suspected electron discharge region; if the number of times that the ultrasonic intensity increases and decreases in a certain sub-region of the power construction area on the surface of the above-mentioned ultrasonic intensity change time domain repetition feature is less than the preset number threshold, it indicates that the local discharge in the above-mentioned sub-region is an accidental low-probability event, and the above-mentioned sub-region is not determined as a suspected electron discharge region. In the preliminary detection process of the power construction area, a global ultrasonic scanning and acquisition is first performed on the power construction area to identify the suspected electron discharge region in the power construction area, which can effectively narrow the visual detection range of local discharge, reduce the workload of full-range inspection of the power construction area, and accurately locate the local discharge in the early stage. Considering that the ultrasonic sensor array directly detects the ultrasonic intensity data and there may be large interference, it is impossible to accurately observe its temporal change state from the change of the ultrasonic intensity data itself. For this reason, Figure 2 As shown, the ultrasonic intensity data detected by the ultrasonic sensor array is transformed to obtain a time-frequency diagram corresponding to the change of ultrasonic intensity. Figure 2 The corresponding figure is the time-frequency diagram of the suspected electron-discharging area. Figure 2 It can be seen that the time-frequency diagram of the suspected discharge area clearly reflects the change of ultrasonic intensity in the area, and it fully presents the situation of the ultrasonic intensity increasing and decreasing in the corresponding time period. Only when a sub-area in the power construction area belongs to the suspected discharge area, the time-frequency diagram corresponding to the change of ultrasonic intensity will be shown as follows Figure 2 The multiple increase-to-decrease events shown in the figure are as follows; when a sub-area within the power construction area does not belong to the suspected discharge area, the time-frequency diagram corresponding to the change in ultrasonic intensity cannot be shown. Figure 2 The multiple increase-to-decrease events shown are based on the time-frequency diagram corresponding to the ultrasonic intensity changes in each sub-area within the power construction area, which can accurately determine whether each sub-area belongs to a suspected electron discharge area.

[0028] After a discharge event occurs in a suspected discharge area, the ultrasonic wave generated by the discharge event will be transmitted in a directional manner in the environment. When the ultrasonic wave passes through an object, it will induce a thermal effect, and the ultrasonic wave energy will be partially or completely transferred to the object. The temperature of the part of the object that receives the ultrasonic wave will increase, and the ultrasonic wave intensity will be attenuated accordingly, which may cause the ultrasonic sensor array to be unable to detect the existence of the ultrasonic wave. It can be seen that the ultrasonic thermal effect will affect the detection accuracy and reliability of the ultrasonic wave. In actual partial discharge detection, if only ultrasonic signals are detected, false detection or missed detection is likely to occur. Considering that when a partial discharge occurs in a suspected discharge area, the ultrasonic wave generated can provide a relatively comprehensive and accurate visual indication of the partial discharge phenomenon, it is necessary to rely on directional and continuous ultrasonic acquisition of the suspected discharge area, and use the collected ultrasonic signal data to perform a comprehensive and basic characterization of the partial discharge phenomenon in the suspected discharge area; then use the thermal infrared signal data obtained by thermal infrared detection of the suspected discharge area to perform deviation calibration on the partial discharge fault location determined based on ultrasonic acquisition and analysis, which can accurately determine the false detection that occurs only by detecting ultrasonic signals.

[0029] Specifically, the robot's built-in ultrasonic sensor array and thermal infrared sensor array can be used to conduct directional and continuous ultrasonic acquisition and thermal infrared detection of the suspected discharge area, and obtain the time-domain continuous data of the spatial distribution of ultrasonic intensity in the suspected discharge area and the time-domain continuous data of the spatial distribution of thermal infrared radiation intensity of all objects in the suspected discharge area; wherein the above-mentioned time-domain continuous data of the spatial distribution of ultrasonic intensity refers to the continuous change data of the intensity value of the ultrasonic intensity at each position point in the entire range of the suspected discharge area over time; the above-mentioned time-domain continuous data of the spatial distribution of thermal infrared radiation intensity refers to the continuous change data of the intensity value of the thermal infrared radiation intensity formed by all objects in the suspected discharge area after receiving ultrasonic waves. The ultrasonic signal data and thermal infrared signal data comprehensively characterize the ultrasonic intensity distribution state generated by local discharge in the suspected discharge area and the thermal infrared radiation intensity distribution state formed by the object after receiving ultrasonic waves, and provide reliable data for the subsequent comprehensive characterization of the local discharge fault point location in the suspected discharge area and the deviation of the above-mentioned fault point location.

[0030] Furthermore, based on the ultrasonic signal data, the distribution of partial discharge fault points in the power construction area is determined, specifically: Performing spatiotemporal frame processing on the time-domain continuous data of the ultrasonic intensity spatial distribution of the suspected electron-discharging region to obtain a number of ultrasonic intensity spatial distribution data frames of the suspected electron-discharging region; performing ultrasonic beam edge recognition and time-domain inversion on the several ultrasonic intensity spatial distribution data frames to obtain the ultrasonic beam transmission path inside the suspected electron-discharging region; The transmission path of the ultrasonic beam is spatially traced to obtain the distribution of local discharge fault points inside the suspected sub-discharge area; wherein the local discharge fault point distribution includes the spatial occupation range of the local discharge fault points inside the suspected sub-discharge area.

[0031] When local discharge occurs in the suspected discharge area, the local discharge will induce the generation of ultrasonic waves. The generated ultrasonic waves will be transmitted in the environment and form a corresponding transmission path. If the transmission process of the ultrasonic waves is continuously detected, every time the ultrasonic wave is transmitted to a certain position in the environmental space, the above-mentioned position will have corresponding ultrasonic energy. For this reason, the time-domain continuous data of the spatial distribution of the ultrasonic wave intensity in the suspected discharge area fully characterizes the position change of the energy distribution formed in the environmental space during the transmission of the ultrasonic wave along the corresponding transmission path. In this way, by inverting the above-mentioned energy distribution position change, the actual transmission path of the ultrasonic wave generated by the local discharge inside the suspected discharge area can be obtained. Figure 3 As shown, a two-dimensional spatial distribution diagram of the ultrasonic intensity of a suspected discharge region at a certain time point is displayed. The suspected discharge region is divided into a grid shape, and each grid unit has a corresponding ultrasonic intensity distribution. The darker the color of the grid unit in the figure, the greater the ultrasonic intensity corresponding to the grid unit, and the lighter the color of the grid unit, the smaller the ultrasonic intensity corresponding to the grid unit. It can be understood that the more concentrated the ultrasonic energy is in the darkest grid unit in the suspected discharge region, that is, the darkest grid unit is most likely to have a local discharge fault point. In order to further confirm the location of the local discharge fault point, the time domain continuous data of the ultrasonic intensity spatial distribution of the suspected discharge region is processed in time and space to obtain several ultrasonic intensity spatial distribution data frames of the suspected discharge region. Each ultrasonic intensity spatial distribution data frame represents the spatial distribution of the ultrasonic intensity in the suspected discharge region at the corresponding time point. The above ultrasonic intensity spatial distribution reflects the ultrasonic energy spatial distribution of the suspected discharge region at the corresponding time point, and the above ultrasonic energy spatial distribution corresponds to the edge of the ultrasonic beam. By performing ultrasonic beam edge recognition and time domain inversion on several ultrasonic intensity spatial distribution data frames, the ultrasonic beam edge boundary at each moment during the directional continuous ultrasonic acquisition is obtained, and the ultrasonic beam edge boundary at all moments during the directional continuous ultrasonic acquisition is inverted in the time domain, so that the ultrasonic transmission path inside the suspected discharge area can be obtained. Then the ultrasonic transmission path is spatially traced to determine the starting point of the ultrasonic transmission path, and the above starting point is used as the local discharge fault point inside the suspected discharge area, so that the starting points of all ultrasonic transmission paths are combined to obtain the distribution of local discharge fault points, accurately determine the spatial occupation range of local discharge fault points inside the suspected discharge area, and comprehensively locate local discharge fault points within the entire range of the power construction area.

[0032] S200, determining ultrasonic thermal effect characteristics of a vicinity of a partial discharge fault point based on thermal infrared signal data; and estimating deviation information of a distribution of the partial discharge fault point based on the ultrasonic thermal effect characteristics.

[0033] Furthermore, based on the thermal infrared signal data, the ultrasonic thermal effect characteristics of the vicinity of the partial discharge fault point are determined; based on the ultrasonic thermal effect characteristics, the deviation information of the distribution of the partial discharge fault point is estimated, specifically: Based on the distribution of partial discharge fault points, the contour features of objects adjacent to the partial discharge fault points are calibrated; based on the contour features, the thermal infrared signal sub-data of the adjacent objects are extracted from the thermal infrared signal data; The heat accumulation positioning analysis is performed on the thermal infrared signal sub-data to determine the location boundary of the local object near the partial discharge fault point where the ultrasonic thermal effect occurs. Based on the location boundary and the spatial occupancy range of the partial discharge fault point, the fault points with incorrect positioning in the partial discharge fault point distribution and their positioning deviation are estimated.

[0034] From the above analysis, it can be seen that ultrasound has strong penetrability. The ultrasound detected by the built-in ultrasonic sensor array of the robot may be the ultrasound after passing through the object inside the suspected discharge area. At this time, the intensity of the ultrasound will decay due to the thermal effect after passing through the object, so that the edge boundary of the ultrasonic energy in the space will shrink accordingly, resulting in a corresponding deviation in the position of the partial discharge fault point determined by the ultrasound detected by the ultrasonic sensor array. Generally speaking, the greater the intensity attenuation of the ultrasound due to the thermal effect, the greater the position deviation of the determined partial discharge fault point. In addition, the energy of the ultrasound itself will be transferred to the object due to the thermal effect during the process of passing through the object. The more energy the ultrasound transfers to the object, the higher the temperature of the part of the object passed by the ultrasound, the greater the intensity of the thermal infrared radiation of the corresponding part, and the larger the range of the thermal infrared radiation. According to the above-mentioned ultrasonic thermal effect on the object and its influence on the positioning deviation of the partial discharge fault point, the positioning deviation of the partial discharge fault point can be determined by performing thermal infrared detection and analysis on the object.

[0035] Specifically, based on the location of the partial discharge fault point included in the partial discharge fault point distribution, the full range image of the suspected discharge sub-area is recognized, and the contour features of the objects adjacent to the partial discharge fault point are calibrated; wherein, the full range image of the suspected discharge sub-area is obtained by taking a picture of the robot's built-in camera; the contour features of the objects adjacent to the partial discharge fault point may be, but are not limited to, the contour features of the objects whose distance from the partial discharge fault point is less than or equal to a preset distance threshold. Then, based on the contour features of the adjacent objects, the thermal infrared signal sub-data of the adjacent objects are extracted from the thermal infrared signal data, so that the above thermal infrared signal sub-data fully and accurately reflect the thermal infrared radiation signal intensity of the adjacent objects in the full range.

[0036] Considering that the thermal infrared signal sub-data comprehensively and accurately reflects the thermal infrared radiation signal intensity of the entire range of the neighboring objects, as the ultrasonic wave generated by the partial discharge passes through the object, the ultrasonic wave transfers part of its own energy to the object due to the thermal effect, and the part of the object passed by the ultrasonic wave continuously accumulates heat. The coverage range of the ultrasonic wave in the object where the thermal effect occurs is consistent with the range of the part of the object passed by the ultrasonic wave. By determining the range of the part of the object passed by the ultrasonic wave, it is possible to determine the process of the ultrasonic thermal effect on the object and its influence on the positioning deviation of the partial discharge fault point. Specifically, the thermal infrared signal sub-data is subjected to heat accumulation positioning analysis to obtain the range of the part where the heat accumulation increases inside the object, thereby determining the part boundary where the ultrasonic thermal effect occurs in the neighboring object of the partial discharge fault point. Based on the above-mentioned part boundary, the spatial occupation range of the previously determined partial discharge fault point is inverted and calculated, the fault point and its positioning deviation in the distribution of the partial discharge fault point are estimated, and the positioning deviation information in the distribution of the partial discharge fault point is accurately calibrated.

[0037] S300, based on the infrared absorption spectrum data of the power construction area, the deviation information is corrected to obtain a visualized distribution map of partial discharge faults in the power construction area.

[0038] Furthermore, based on the infrared absorption spectrum data of the power construction area, the deviation information is corrected to obtain a visualization distribution map of partial discharge faults in the power construction area, specifically: Analyze the infrared absorption spectrum data of the distribution range of the partial discharge fault points in the power construction area to obtain the preset gas space movement characteristics of the distribution range of the partial discharge fault points; based on the preset gas space movement characteristics, correct the positioning deviation of the fault points that are incorrectly positioned in the distribution of the partial discharge fault points; Based on the corrected partial discharge fault point distribution, the fault point density and fault point discharge intensity are calculated to determine the high-voltage electrical breakdown sub-area distribution information of the power construction area, thereby generating a visualized distribution map of partial discharge faults in the power construction area.

[0039] The high voltage electricity released during the local discharge in the power construction area will break through the air, causing the oxygen in the air to react and / or causing the oxygen to react with nitrogen to generate specific types of gases such as ozone and / or nitric oxide. These specific types of gases have good stability and can remain in the air and diffuse and spread. The concentration and diffusion of these specific types of gases are only related to the intensity of local discharge, and the influence of the external environment or objects on them can be ignored. By detecting the propagation and diffusion of these specific types of gases, the diffusion source of the gas can be obtained, and the location of the local discharge that produces these specific types of gases can be accurately determined. Generally speaking, these specific types of gases have unique infrared absorption peaks. By detecting the infrared absorption peaks of the air in the distribution range of the local discharge fault point, the specific location of these specific types of gases in the distribution range of the local discharge fault point can be determined.

[0040] Specifically, the infrared absorption spectrum data of the distribution range of the local discharge fault point in the power construction area is analyzed to obtain the infrared absorption peaks of the air at different positions in the distribution range of the local discharge fault point; wherein the infrared absorption spectrum data can be detected by the built-in infrared spectrum sensor of the robot. The infrared absorption peak is compared with the infrared absorption peak of a specific type of gas to determine whether the air at different positions contains a specific type of gas, thereby obtaining the preset gas space movement position change characteristics of the distribution range of the local discharge fault point. The preset gas space movement position change characteristics are inverted to obtain the source position of the specific type of gas, thereby correcting the positioning deviation of the fault point that is incorrectly located in the distribution of the local discharge fault point. In addition, based on the corrected local discharge fault point distribution, the fault point density and the fault point discharge intensity are calculated to determine the high-voltage electrical breakdown sub-region distribution information of the power construction area; wherein, the greater the fault point density and / or the greater the fault point discharge intensity, the greater the probability of a high-voltage electrical breakdown event occurring in the corresponding area; and based on the high-voltage electrical breakdown sub-region distribution information of the power construction area, a local discharge fault visualization distribution map of the power construction area is generated, which can visualize the local discharge faults in the entire range of the power construction area and realize full-range and high-precision local discharge positioning of the power construction area.

[0041] See also Figure 4 As shown, the present invention provides a visual detection system for partial discharge in power construction, which includes the following modules: The ultrasonic acquisition module is used to collect ultrasonic waves in the power construction area to obtain ultrasonic signal data in the power construction area; Thermal infrared detection module, used to perform thermal infrared detection on the power construction area and obtain thermal infrared signal data of the power construction area; A partial discharge fault point determination module is used to determine the distribution of partial discharge fault points in the power construction area based on ultrasonic signal data; The fault point distribution deviation estimation module is used to determine the ultrasonic thermal effect characteristics of the vicinity of the partial discharge fault point based on the thermal infrared signal data; based on the ultrasonic thermal effect characteristics, estimate the deviation information of the partial discharge fault point distribution; Deviation correction module, used to correct deviation information based on infrared absorption spectrum data of power construction area; The visualization map generation module is used to generate a visualization distribution map of partial discharge faults in the power construction area.

[0042] Furthermore, before the ultrasonic collection module collects ultrasonic waves in the power construction area, it also includes: Perform global ultrasonic scanning and acquisition of the power construction area to obtain the time domain recurrence characteristics of the ultrasonic intensity change in the power construction area in several scanning cycles; based on the time domain recurrence characteristics of the ultrasonic intensity change, identify the suspected discharge electron area in the power construction area; The ultrasonic acquisition module is used to collect ultrasonic waves in the power construction area to obtain ultrasonic signal data in the power construction area, specifically: Directed continuous ultrasonic acquisition is performed on the suspected electron-discharging area to obtain ultrasonic signal data of the suspected electron-discharging area; wherein the ultrasonic signal data includes continuous time-domain data of the spatial distribution of ultrasonic intensity of the suspected electron-discharging area; The thermal infrared detection module is used to perform thermal infrared detection on the power construction area to obtain the thermal infrared signal data of the power construction area, specifically: Thermal infrared detection is performed on the suspected electron-discharging area to obtain thermal infrared signal data of the suspected electron-discharging area; wherein the thermal infrared signal data includes the spatial distribution and time domain continuous data of the thermal infrared radiation intensity of all objects in the suspected electron-discharging area.

[0043] Furthermore, the partial discharge fault point determination module is used to determine the distribution of partial discharge fault points in the power construction area based on the ultrasonic signal data, specifically: Performing spatiotemporal frame processing on the time-domain continuous data of the ultrasonic intensity spatial distribution of the suspected electron-discharging region to obtain a number of ultrasonic intensity spatial distribution data frames of the suspected electron-discharging region; performing ultrasonic beam edge recognition and time-domain inversion on the several ultrasonic intensity spatial distribution data frames to obtain the ultrasonic beam transmission path inside the suspected electron-discharging region; The transmission path of the ultrasonic beam is spatially traced to obtain the distribution of local discharge fault points inside the suspected sub-discharge area; wherein the local discharge fault point distribution includes the spatial occupation range of the local discharge fault points inside the suspected sub-discharge area.

[0044] Furthermore, the fault point distribution deviation estimation module is used to determine the ultrasonic thermal effect characteristics of the vicinity of the partial discharge fault point based on the thermal infrared signal data; based on the ultrasonic thermal effect characteristics, the deviation information of the partial discharge fault point distribution is estimated, specifically: Based on the distribution of partial discharge fault points, the contour features of objects adjacent to the partial discharge fault points are calibrated; based on the contour features, the thermal infrared signal sub-data of the adjacent objects are extracted from the thermal infrared signal data; The heat accumulation positioning analysis is performed on the thermal infrared signal sub-data to determine the location boundary of the local object near the partial discharge fault point where the ultrasonic thermal effect occurs. Based on the location boundary and the spatial occupancy range of the partial discharge fault point, the fault points with incorrect positioning in the partial discharge fault point distribution and their positioning deviation are estimated.

[0045] Furthermore, the deviation correction module is used to correct the deviation information based on the infrared absorption spectrum data of the power construction area, specifically: Analyze the infrared absorption spectrum data of the distribution range of the partial discharge fault points in the power construction area to obtain the preset gas space movement characteristics of the distribution range of the partial discharge fault points; based on the preset gas space movement characteristics, correct the positioning deviation of the fault points that are incorrectly positioned in the distribution of the partial discharge fault points; The visualization map generation module is used to generate a visualization distribution map of partial discharge faults in the power construction area, specifically: Based on the corrected partial discharge fault point distribution, the fault point density and fault point discharge intensity are calculated to determine the high-voltage electrical breakdown sub-area distribution information of the power construction area, thereby generating a visualized distribution map of partial discharge faults in the power construction area.

[0046] The operation and effect of the electric power construction partial discharge visualization detection system of the present invention are corresponding to and consistent with the above-mentioned electric power construction partial discharge visualization detection method, and the electric power construction partial discharge visualization detection system will not be repeated here.

[0047] Through the description of the above embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by adding a necessary general hardware platform, and of course can also be implemented by combining hardware and software. Based on such an understanding, the above technical solution can essentially or in other words be embodied in the form of a computer product, and the present invention can be implemented in the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program codes.

[0048] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it, and other embodiments may also be used. Although the present invention has been described in detail with reference to the aforementioned embodiments, ordinary technicians in this field should understand that they can still modify the technical solutions recorded in the aforementioned embodiments, or replace some of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A visual detection method for partial discharge in power construction, characterized in that: The method comprises the following steps: Performing ultrasonic collection and thermal infrared detection on the power construction area to obtain ultrasonic signal data and thermal infrared signal data of the power construction area; determining the distribution of partial discharge fault points in the power construction area based on the ultrasonic signal data; Based on the thermal infrared signal data, determining the ultrasonic thermal effect characteristics of the vicinity of the partial discharge fault point; based on the ultrasonic thermal effect characteristics, estimating the deviation information of the distribution of the partial discharge fault point; Based on the infrared absorption spectrum data of the power construction area, the deviation information is corrected to obtain a visualized distribution map of partial discharge faults in the power construction area.

2. The method according to claim 1, characterized in that The ultrasonic wave collection and thermal infrared detection are performed on the power construction area to obtain the ultrasonic wave signal data and thermal infrared signal data of the power construction area, specifically: Performing global ultrasonic scanning and acquisition on the power construction area to obtain the time domain recurrence characteristics of the ultrasonic intensity change in the power construction area in several scanning cycles; based on the time domain recurrence characteristics of the ultrasonic intensity change, identifying the suspected discharge electron area in the power construction area; Directional continuous ultrasonic collection and thermal infrared detection are performed on the suspected electron-discharging area to obtain ultrasonic signal data and thermal infrared signal data of the suspected electron-discharging area; wherein the ultrasonic signal data includes time-domain continuous data on the spatial distribution of ultrasonic intensity of the suspected electron-discharging area; and the thermal infrared signal data includes time-domain continuous data on the spatial distribution of thermal infrared radiation intensity of all objects in the suspected electron-discharging area.

3. The method according to claim 2, characterized in that The determining of the distribution of partial discharge fault points in the power construction area based on the ultrasonic signal data is specifically as follows: Performing spatiotemporal frame processing on the time-domain continuous data of the ultrasonic intensity spatial distribution of the suspected electron-discharging region to obtain a number of ultrasonic intensity spatial distribution data frames of the suspected electron-discharging region; performing ultrasonic beam edge recognition and time-domain inversion on the several ultrasonic intensity spatial distribution data frames to obtain the ultrasonic beam transmission path inside the suspected electron-discharging region; The ultrasonic beam transmission path is spatially traced to obtain the distribution of local discharge fault points inside the suspected sub-discharge area; wherein the local discharge fault point distribution includes the spatial occupation range of the local discharge fault points inside the suspected sub-discharge area.

4. The method according to claim 1, characterized in that: The method of determining the ultrasonic thermal effect characteristics of the vicinity of the partial discharge fault point based on the thermal infrared signal data; and estimating the deviation information of the distribution of the partial discharge fault point based on the ultrasonic thermal effect characteristics, is specifically as follows: Based on the distribution of the partial discharge fault points, calibrate the contour features of the objects adjacent to the partial discharge fault points; based on the contour features, extract the thermal infrared signal sub-data of the adjacent objects from the thermal infrared signal data; Perform heat accumulation positioning analysis on the thermal infrared signal sub-data to determine the site boundary of the local discharge fault point where the ultrasonic thermal effect occurs in the object adjacent to the local discharge fault point; based on the site boundary and the spatial occupation range of the local discharge fault point, estimate the fault points with incorrect positioning in the local discharge fault point distribution and their positioning deviations.

5. The method according to claim 1, characterized in that: The deviation information is corrected based on the infrared absorption spectrum data of the power construction area to obtain a visualized distribution map of partial discharge faults in the power construction area, specifically: Analyze the infrared absorption spectrum data of the distribution range of the local discharge fault points in the power construction area to obtain the preset gas space movement characteristics of the distribution range of the local discharge fault points; based on the preset gas space movement characteristics, correct the positioning deviation of the fault points that are incorrectly positioned in the distribution of the local discharge fault points; Based on the corrected partial discharge fault point distribution, the fault point density and fault point discharge intensity are calculated to determine the high-voltage electrical breakdown sub-area distribution information of the power construction area, thereby generating a visualized distribution map of partial discharge faults in the power construction area.

6. A visual detection system for partial discharge in power construction, characterized in that: The system includes the following modules: An ultrasonic acquisition module is used to perform ultrasonic acquisition on the electric power construction area to obtain ultrasonic signal data of the electric power construction area; A thermal infrared detection module is used to perform thermal infrared detection on the power construction area to obtain thermal infrared signal data of the power construction area; A partial discharge fault point determination module, used to determine the distribution of partial discharge fault points in the power construction area based on the ultrasonic signal data; A fault point distribution deviation estimation module is used to determine the ultrasonic thermal effect characteristics of the vicinity of the partial discharge fault point based on the thermal infrared signal data; based on the ultrasonic thermal effect characteristics, estimate the deviation information of the partial discharge fault point distribution; A deviation correction module, used for correcting the deviation information based on the infrared absorption spectrum data of the power construction area; The visualization map generation module is used to generate a visualization distribution map of partial discharge faults in the power construction area.

7. The system according to claim 6, characterized in that Before the ultrasonic collection module collects ultrasonic waves in the power construction area, it also includes: Performing global ultrasonic scanning and acquisition on the power construction area to obtain the time domain recurrence characteristics of the ultrasonic intensity change in the power construction area in several scanning cycles; based on the time domain recurrence characteristics of the ultrasonic intensity change, identifying the suspected discharge electron area in the power construction area; The ultrasonic acquisition module is used to perform ultrasonic acquisition on the power construction area to obtain ultrasonic signal data of the power construction area, specifically: Directed continuous ultrasonic acquisition is performed on the suspected electron-discharging region to obtain ultrasonic signal data of the suspected electron-discharging region; wherein the ultrasonic signal data includes continuous spatial distribution time-domain data of ultrasonic intensity of the suspected electron-discharging region; The thermal infrared detection module is used to perform thermal infrared detection on the power construction area to obtain thermal infrared signal data of the power construction area, specifically: Thermal infrared detection is performed on the suspected electron-discharging area to obtain thermal infrared signal data of the suspected electron-discharging area; wherein the thermal infrared signal data includes time-domain continuous data of the spatial distribution of thermal infrared radiation intensity of all objects in the suspected electron-discharging area.

8. The system according to claim 7, characterized in that The local discharge fault point determination module is used to determine the local discharge fault point distribution in the power construction area based on the ultrasonic signal data, specifically: Performing spatiotemporal frame processing on the time-domain continuous data of the ultrasonic intensity spatial distribution of the suspected electron-discharging region to obtain a number of ultrasonic intensity spatial distribution data frames of the suspected electron-discharging region; performing ultrasonic beam edge recognition and time-domain inversion on the several ultrasonic intensity spatial distribution data frames to obtain the ultrasonic beam transmission path inside the suspected electron-discharging region; The ultrasonic beam transmission path is spatially traced to obtain the distribution of local discharge fault points inside the suspected sub-discharge area; wherein the local discharge fault point distribution includes the spatial occupation range of the local discharge fault points inside the suspected sub-discharge area.

9. The system according to claim 6, characterized in that The fault point distribution deviation estimation module is used to determine the ultrasonic thermal effect characteristics of the vicinity of the partial discharge fault point based on the thermal infrared signal data; based on the ultrasonic thermal effect characteristics, estimate the deviation information of the partial discharge fault point distribution, specifically: Based on the distribution of the partial discharge fault points, calibrate the contour features of the objects adjacent to the partial discharge fault points; based on the contour features, extract the thermal infrared signal sub-data of the adjacent objects from the thermal infrared signal data; Perform heat accumulation positioning analysis on the thermal infrared signal sub-data to determine the site boundary of the local discharge fault point where the ultrasonic thermal effect occurs in the object adjacent to the local discharge fault point; based on the site boundary and the spatial occupation range of the local discharge fault point, estimate the fault points with incorrect positioning in the local discharge fault point distribution and their positioning deviations.

10. The system according to claim 6, characterized in that The deviation correction module is used to correct the deviation information based on the infrared absorption spectrum data of the power construction area, specifically: Analyze the infrared absorption spectrum data of the distribution range of the local discharge fault points in the power construction area to obtain the preset gas space movement characteristics of the distribution range of the local discharge fault points; based on the preset gas space movement characteristics, correct the positioning deviation of the fault points that are incorrectly positioned in the distribution of the local discharge fault points; The visualization map generation module is used to generate a visualization distribution map of partial discharge faults in the power construction area, specifically: Based on the corrected partial discharge fault point distribution, the fault point density and fault point discharge intensity are calculated to determine the high-voltage electrical breakdown sub-area distribution information of the power construction area, thereby generating a visualized distribution map of partial discharge faults in the power construction area.

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