Method and system for detecting arc striking phenomenon of power distribution cabinet

Abstract

The invention relates to the technical field of power distribution cabinet safety detection, in particular to a power distribution cabinet arc striking phenomenon detection method and system. The method comprises the steps of obtaining an image in a power distribution cabinet; when the long-strip-shaped highlight area exists in the in-cabinet image, end areas corresponding to the two end positions of the long-strip-shaped highlight area are constructed; dividing the long-strip-shaped highlight area into a plurality of sub-areas, judging whether the number of the long-strip-shaped highlight targets contained in each sub-area is 1 or not, and if yes, judging whether the brightness difference between the two end areas is larger than a preset brightness difference threshold value or not; and if yes, judging whether the brightness from one end part to the other end part is monotonically increased or monotonically decreased, and if yes, judging that an arc striking phenomenon occurs in the power distribution cabinet. According to the invention, whether an arcing abnormal phenomenon occurs in the power distribution cabinet can be accurately detected.

Description

Technical Field

[0001] The present invention relates to the technical field of safety detection of power distribution cabinets, and particularly to a method and system for detecting the arc starting phenomenon of power distribution cabinets. Background Art

[0002] In modern power systems, power distribution cabinets are one of the key facilities in the process of power transmission and distribution. There are usually many key components inside power distribution cabinets, such as busbars, terminal heads, etc. These components play an important role in power transmission and distribution. They work together to ensure that power can be safely, stably and efficiently delivered to each electrical equipment and area.

[0003] During the actual operation of substations, due to climatic reasons, accidents caused by condensation occur frequently. This is mainly because of the need for cable inlets and outlets, and power distribution cabinet equipment is usually connected to cable channels. In rainy seasons such as summer, due to reasons such as rainwater accumulation and poor ventilation, the humidity in the cable channel is usually high. A large amount of moisture accumulates in the cable channel, laying a hidden danger for subsequent problems. In cold seasons such as autumn and winter, the situation is equally worrying. The temperature in the cable channel is higher than the outdoor ambient temperature. When the sealing condition of the cable holes is not ideal, hot and humid air enters the power distribution cabinet from the bottom. In the low-temperature environment inside the cabinet, the air will become supersaturated with water vapor, and some water vapor will condense and precipitate to cover the surface of the equipment. This condensed water vapor will reduce the insulation performance of equipment such as cable terminals and insulating bushings. When the insulation performance drops to a certain level, it is easy to cause the arc starting phenomenon. For example, at the electrical connection points of the equipment, when the insulation is good, the current passes through stably. When condensation causes the insulation performance to deteriorate, the air is broken down to form an arc. This arc starting is likely to form abnormal phenomena such as flashover, which can not only directly lead to equipment operation failures, but also induce the premature development of internal defects of the equipment into operation failures. In severe cases, the arc starting will cause insulation breakdown, and the strong current will cause the terminal to burn out, and even cause the cabinet to explode, posing a serious threat to the safe and stable operation of the substation.

[0004] Due to the discontinuous occurrence characteristic of the arc starting phenomenon, it poses a great challenge to the conventional inspection methods. Most conventional inspection methods rely on manual periodic inspections, and the inspection cycle is usually in units of days, weeks or even months. Within such a long time interval, the arc starting phenomenon may only occur in a short moment. If the starting time is not within the inspection period of the inspection personnel, it is very easy to be missed. Moreover, the environment inside the power distribution cabinet is relatively complex, with many electrical components and circuits. These devices will also generate various signals such as sounds and heats during normal operation, which are likely to interfere with the inspection personnel's judgment of the arc starting phenomenon, making it difficult for the inspection personnel to accurately identify the starting phenomenon from the complex background information even when on site. Summary of the Invention

[0005] To this end, the technical problem to be solved by the present invention is to overcome the defect that it is difficult to detect the discontinuous arc starting phenomenon by the existing conventional inspection method, resulting in the difficulty in timely discovery and prevention of equipment failures.

[0006] To solve the above technical problem, the present invention provides a method for detecting the arc starting phenomenon in a distribution cabinet, including the following steps: Obtain the image inside the distribution cabinet. When there is a long and strip-shaped high-brightness area in the cabinet image, construct the end regions corresponding to the two ends of the long and strip-shaped high-brightness area; Divide the long and strip-shaped high-brightness area into multiple sub-regions, and judge whether the number of long and strip-shaped high-brightness targets contained in each sub-region is 1. If so, judge whether the brightness difference between the two end regions of the long and strip-shaped high-brightness area is greater than a preset brightness difference threshold. If it is greater, judge whether the brightness change from one end to the other end is monotonically increasing or decreasing. If so, it is determined that an arc starting phenomenon has occurred inside the distribution cabinet.

[0007] Preferably, pass the cabinet image through a pre-trained object detection model to identify the square area where the highlight is located in the cabinet image; Judge whether the aspect ratio of the square area where the highlight is located in the cabinet image is greater than a preset ratio. If it is greater, it is determined that the high-brightness area in the square area where the highlight is located is long and strip-shaped, and extract the high-brightness area to obtain the long and strip-shaped high-brightness area.

[0008] Preferably, after it is determined that an arc starting phenomenon has occurred inside the distribution cabinet, judge whether there is a square area where the highlight is located with an aspect ratio within a preset range in the cabinet image after an interval of one time sequence. If so, judge whether there is the long and strip-shaped high-brightness area based on which the arc starting phenomenon was determined in the previous time sequence. If so, judge whether there is an intersection between the square area where the highlight is located and the long and strip-shaped high-brightness area based on which the arc starting phenomenon was determined in the previous time sequence. If there is an intersection, it is determined that a gas flow contact arc phenomenon has occurred inside the distribution cabinet at this time sequence; wherein, the upper limit value of the preset range is less than the preset ratio; After it is determined that a gas flow contact arc phenomenon has occurred inside the distribution cabinet, judge whether there is a square area where the highlight is located with an aspect ratio within a preset range in the cabinet image after an interval of one time sequence. If so, judge whether an arc starting phenomenon has occurred inside the distribution cabinet at this time sequence. If not, it is determined that a strong gas flow arc blowing phenomenon has occurred inside the distribution cabinet at this time sequence; When the distribution cabinet successively has an arc starting phenomenon, a gas flow contact arc phenomenon, and a strong gas flow arc blowing phenomenon in three consecutive adjacent time sequences, it is determined that a flashover phenomenon has occurred in the distribution cabinet.

[0009] Preferably, based on the two end positions of the long and strip-shaped high-brightness area and the average width of the long and strip-shaped high-brightness area, construct the end region corresponding to each end.

[0010] Preferably, the process of obtaining the average width of the elongated highlighted area includes: According to the direction perpendicular to the long side of the minimum circumscribed rectangle of the elongated highlighted area, draw multiple line segments passing through the elongated highlighted area at a preset interval, and calculate the average value of the distances between the two intersection points of each line segment and the boundary of the elongated highlighted area as the average width of the elongated highlighted area.

[0011] Preferably, constructing an end area corresponding to each end based on the two end positions of the elongated highlighted area and the average width of the elongated highlighted area includes: Taking each end position as the center and the average width of the elongated highlighted area as the side length or diameter, construct a square area or a circular area as the end area corresponding to this end.

[0012] Preferably, if the angle between the line connecting one end of the elongated highlighted area to the other end and the horizontal direction is less than 45°, the elongated highlighted area is vertically divided into multiple sub-areas; If the angle between the line connecting one end of the elongated highlighted area to the other end and the horizontal direction is greater than 45°, the elongated highlighted area is horizontally divided into multiple sub-areas; If the angle between the line connecting one end of the elongated highlighted area to the other end and the horizontal direction is equal to 45°, the elongated highlighted area is horizontally or vertically divided into multiple sub-areas.

[0013] Preferably, if the number of elongated highlighted targets contained in a sub-area of the elongated highlighted area is greater than 1, it is determined that the elongated highlighted area does not meet the conditions of the arc starting phenomenon, and no subsequent judgment is made, and the next elongated highlighted area is continued to be processed.

[0014] Preferably, the method for judging that the brightness from one end of the elongated highlighted area to the other end is monotonically increasing or decreasing includes: Taking the average value of the brightness of each pixel point in each sub-area as the brightness of each sub-area; According to the extension direction from one end of the elongated highlighted area to the other end, determine the brightness difference between the brightness of the subsequent sub-area and the brightness of the previous sub-area to obtain brightness differences; where is the number of sub-areas; Count the number of brightness differences greater than 0 and less than 0 among the brightness differences. If the number of brightness differences greater than 0 among the When the number of luminance differences less than 0 among the luminance differences is greater than a preset luminance difference number judgment threshold, it is determined that the luminance from one end to the other end of the long strip-shaped high-brightness region is monotonically decreasing.

[0015] The present invention also provides an arc starting phenomenon detection system for a power distribution cabinet, including: An image acquisition module for acquiring an image inside the power distribution cabinet; An end region construction module for constructing end regions corresponding to the two ends of the long strip-shaped high-brightness region when there is a long strip-shaped high-brightness region in the image inside the cabinet; A judgment module for dividing the long strip-shaped high-brightness region into multiple sub-regions, judging whether the number of long strip-shaped high-brightness targets included in each sub-region is 1, if so, judging whether the luminance difference between the two end regions of the long strip-shaped high-brightness region is greater than a preset luminance difference threshold, if greater, judging whether the luminance change from one end to the other end is monotonically increasing or monotonically decreasing, and if so, determining that an arc starting phenomenon has occurred inside the power distribution cabinet.

[0016] The above technical solution of the present invention has the following beneficial effects compared with the prior art: The arcing phenomenon detection method and system of a distribution cabinet described in the present invention can break through the time limit of conventional inspections and realize continuous monitoring of the internal conditions of the distribution cabinet by performing image detection in the image inside the distribution cabinet. Since the distribution cabinet is usually a dark environment, when arcing occurs in the distribution cabinet, it will be highlighted. According to factors such as the effect of current and the flow of gas, it will usually present a long strip shape. The present invention uses this feature. When there is a long strip of highlighted area in the image inside the cabinet, the present invention preliminarily judges that arcing may occur. Considering that there may be highlights caused by other factors such as light leakage from the distribution box and reflection of equipment in the distribution cabinet, the present invention further combines other characteristics of arcing for accurate judgment. According to the characteristic of arcing that it is curved but not spiral, the long strip of highlighted area is divided into multiple sub-areas, and it is judged whether the number of long strip highlighted targets contained in each sub-area is 1, so as to eliminate some interference. At the same time, according to the characteristic of arcing phenomenon that the brightness gradually decreases from the head to the tail, if the brightness difference between the two end areas is greater than the preset brightness difference threshold, and the brightness from one end to the other is monotonically increasing or monotonically decreasing, by integrating the various characteristics of arcing phenomenon, it is possible to effectively eliminate the interference of high brightness caused by other factors, and realize the accurate identification of arcing phenomenon in the distribution cabinet, breaking through the time limit of conventional inspections, and being able to continuously monitor the internal situation of the distribution cabinet, greatly improving the accuracy of arcing phenomenon judgment in complex environments. In addition, by accurately identifying the arcing phenomenon in the distribution cabinet, it is possible to intervene before the power equipment fails, effectively prevent equipment failure, reduce the complexity of the failure, avoid a large number of component damage and increased maintenance difficulty caused by the deterioration of the failure, thereby reducing maintenance costs.

[0017] In addition, when the gas flow contacts the arc, the gas flow will disturb the arc when it touches the burning arc, changing the gas flow field and energy distribution around the arc. On the cabinet image, this disturbance appears as a large area that intersects with the original long and narrow highlighted area of the arc. Therefore, after determining that an arc initiation phenomenon has occurred in the power distribution cabinet, the present invention determines whether there is a large area in the cabinet image after an interval of one time sequence. The large area refers to an area where the aspect ratio of the length and width of the long and narrow highlighted area is within a set ratio range, and there is the long and narrow highlighted area based on which the arc initiation phenomenon was determined in the previous time sequence. If so, it is determined whether there is an intersection between the highlighted square area and the long and narrow highlighted area based on which the arc initiation phenomenon was determined in the previous time sequence. If there is an intersection, it is determined that a gas flow contacting arc phenomenon has occurred in the power distribution cabinet at the current time sequence. When the gas flow contacting arc phenomenon occurs, the strong gas flow will disperse the arc, causing the arc to extinguish. At this time, there is no new arc initiation phenomenon in the power distribution cabinet, but the energy of the gas flow still exists and will form a large area on the cabinet image. Therefore, after determining that the gas flow contacting arc phenomenon has occurred in the power distribution cabinet, the present invention determines whether the aspect ratio of the highlighted square area is within a preset range in the cabinet image after an interval of one time sequence, and there is no arc initiation phenomenon in the power distribution cabinet. If so, it is determined that a strong gas flow blowing arc phenomenon has occurred in the power distribution cabinet at the current time sequence. Arc initiation is the initial stage of flashover. Subsequently, the gas flow contacts the arc, changing the arc shape and energy distribution. Finally, the strong gas flow blows the arc, causing the arc to extinguish or the arc energy to be greatly weakened. Therefore, by determining whether the power distribution cabinet sequentially experiences an arc initiation phenomenon, a gas flow contacting arc phenomenon, and a strong gas flow blowing arc phenomenon in three consecutive adjacent time sequences, the present invention determines whether a flashover phenomenon occurs in the power distribution cabinet, which can prevent the flashover phenomenon from threatening the safe and stable operation of the substation and ensure the safe and stable operation of the power distribution cabinet. Description of the Drawings

[0018] To make the content of the present invention easier to understand clearly, the following further details the present invention according to specific embodiments of the present invention in conjunction with the drawings, where: Figure 1 is a schematic flow chart of a method for detecting an arc initiation phenomenon in a power distribution cabinet according to the present invention.

[0019] Figure 2 is a schematic diagram for extracting the long and narrow highlighted area.

[0020] Figure 3 is a schematic diagram for dividing the long and narrow highlighted area into multiple sub-regions along the horizontal direction. Figure 3 In (a) is a schematic diagram where the number of long and narrow highlighted targets in each sub-region is 1. Figure 3 In (b) is a schematic diagram where there are two or more long and narrow highlighted targets in the sub-region.

[0021] Figure 4 It is a schematic flow diagram for the recognition of flashover phenomenon.

[0022] Figure 5 It is a schematic diagram of the highlighted box area identified when the cabinet image contains a current image.

[0023] Figure 6 It is a schematic structural diagram of an arc starting phenomenon detection device for a power distribution cabinet provided by an embodiment of the present application. Specific Embodiments

[0024] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments, so that those skilled in the art can better understand the present invention and be able to implement it, but the embodiments given are not intended to limit the present invention.

[0025] In the power system, the arc starting phenomenon is often hidden inside the power distribution cabinet. Due to its discontinuous occurrence characteristics, it is difficult to easily detect by conventional patrol methods. Therefore, in the first embodiment, a method for detecting the arc starting phenomenon in a power distribution cabinet is proposed, which can accurately and timely detect whether there is an abnormal arc starting phenomenon inside the power distribution cabinet.

[0026] Referring to Figure 1 As shown, the first embodiment of the present application provides a method for detecting the arc starting phenomenon in a power distribution cabinet, including the following steps: Step S1: Obtain the image inside the power distribution cabinet. When there is a long strip-shaped highlighted area in the cabinet image, construct the end areas corresponding to the two ends of the long strip-shaped highlighted area; In this embodiment, specifically, the process of obtaining the long strip-shaped highlighted area in the cabinet image is as follows: Based on the cabinet image, detect the highlighted box area in the cabinet image; in the highlighted box area in the cabinet image, extract the long strip-shaped highlighted area through an image segmentation model; the image segmentation model is any one of the U-Net model, SegNet model, and FCN model.

[0027] The highlighted area in the cabinet image is framed by a box, and the formula for the highlighted box area identified in the cabinet image is: , where box represents the highlighted box area in the cabinet image, bx represents the x-axis coordinate of the vertex of the highlighted box area, by represents the y-axis coordinate of the vertex of the highlighted box area, bw represents the width of the highlighted box area, and bh represents the height of the highlighted box area.

[0028] The method for detecting the highlighted box area in the cabinet image is any one of a pre-trained object detection model and a region detection algorithm; The target detection model is any one of the YOLOv10_L target detection model, the Faster R-CNN model, and the Mask R-CNN model; the region detection algorithm is any one of the opencv region detection algorithm and the Canny edge detection algorithm.

[0029] In this embodiment, specifically, when the aspect ratio of the highlighted square region in the cabinet image is greater than a preset ratio, it is determined that the highlighted region in the highlighted square region is a long strip; among them, the value range of the preset ratio is between 3 and 8, and other larger ratios can also be selected. The present application does not specifically limit it.

[0030] The long strip can be a straight long strip or a curved long strip. The present application does not specifically limit it. Since the arc ignition is usually a curved long strip, the above-mentioned highlighted region of the long strip is usually a curved long strip region.

[0031] As Figure 2 shown, Figure 2 It is a schematic diagram for extracting the highlighted region of the long strip. Figure 2 The highlighted region of the long strip in it is a curved long strip region.

[0032] In this embodiment, after detecting the highlighted square region in the cabinet image, the highlighted region of the long strip is extracted from the highlighted square region, which can accurately extract the highlighted region of the long strip in the image, effectively exclude the interference of other irrelevant information in the image, and only focus on the key parts related to the abnormality. Compared with the traditional method of directly analyzing the entire image, this method greatly improves the accuracy of abnormality detection. Because in a complex cabinet environment, there are many factors that may affect the judgment, such as the reflection of the equipment itself and the normal indicator light on. And the method of this embodiment can accurately identify the highlighted part that truly represents the abnormality, reduce misjudgment, thereby providing a more reliable data basis for the analysis and processing of the arc ignition phenomenon, and ensuring the accuracy and reliability of the recognition result of the arc ignition phenomenon.

[0033] In this embodiment, specifically, the end regions corresponding to the two ends of the highlighted region of the long strip are constructed, including: Taking each end as the center, the region composed of pixels with a range less than or equal to the preset distance is used as the end region corresponding to the end.

[0034] Among them, the positions of the two ends of the highlighted region of the long strip are , , The coordinate of , The coordinate of , and the positions of the two ends of the highlighted region of the long strip are the positions where the two endpoints of the highlighted region of the long strip are located.

[0035] In this embodiment, preferably, based on the two end positions of the long strip-shaped highlighted area and the average width of the long strip-shaped highlighted area, an end area corresponding to each end is constructed.

[0036] Optionally, with each end position as the center and the average width of the long strip-shaped highlighted area as the side length, a square area is constructed as the end area corresponding to this end. The formula is: , , wherein, is the end area corresponding to the head end, is the end area corresponding to the tail end. The coordinate of the head end position is , The coordinate of the tail end position is , is the abscissa of the head end position , is the ordinate of the head end position , is the abscissa of the tail end position , is the ordinate of the tail end position , is the average width of the long strip-shaped highlighted area, is the function representation for constructing the rectangular area.

[0037] Optionally, with each end position as the center and the average width of the long strip-shaped highlighted area as the diameter, a circular area is constructed as the end area corresponding to this end.

[0038] In this embodiment, based on the two end positions of the long strip-shaped highlighted area and the average width of the long strip-shaped highlighted area, an end area corresponding to each end is constructed, which can make the determined end area consistent with the overall width of the long strip-shaped highlighted area, so as to comprehensively reflect the overall brightness of each end area and will not affect the accuracy of the end area brightness due to the overly large range of the end area.

[0039] Specifically, in the present invention, the process of obtaining the average width of the long strip-shaped highlighted area includes: Perpendicular to the long side of the minimum circumscribed rectangle of the long strip-shaped highlighted area, draw multiple line segments passing through the long strip-shaped highlighted area at a preset interval, and calculate the average value of the distances between the two intersection points of each line segment and the boundary of the long strip-shaped highlighted area as the average width of the long strip-shaped highlighted area.

[0040] Optionally, according to the direction of the major axis of the minimum circumscribed ellipse perpendicular to the elongated highlighted area, draw multiple line segments penetrating the elongated highlighted area at a preset interval, and calculate the average value of the distances between the two points where each line segment intersects the boundary of the elongated highlighted area as the average width of the elongated highlighted area.

[0041] Optionally, along the extension direction of the elongated highlighted area from one end to the other end, divide the elongated highlighted area into highlight segments, and take the average value of the widths of highlight segments as the average width of the elongated highlighted area. The formula is: , In the formula, is the average width of the elongated highlighted area, is the average value function, is the th width of the highlight segment, ; Among them, there are multiple ways to determine the width of each highlight segment, as follows: For each highlight segment, arbitrarily select a position inside it. Starting from the selected position, along the extension direction of the elongated highlighted area from one end to the other end, measure the distance from the selected position to one side boundary of the current highlight segment as the width of the current highlight segment.

[0042] For each highlight segment, determine the middle position inside it. Starting from the middle position, along the extension direction of the elongated highlighted area from one end to the other end, measure the distance from the middle position to one side boundary of the current highlight segment as the width of the current highlight segment.

[0043] For each highlight segment, arbitrarily select multiple positions inside it. Starting from each selected position respectively, along the extension direction of the elongated highlighted area from one end to the other end, calculate the average value of the distances from each position to one side boundary of the current highlight segment as the width of the current highlight segment.

[0044] Step S2: Divide the elongated highlighted area into multiple sub-areas, and determine whether the number of elongated highlighted targets contained in each sub-area is 1. If so, determine whether the brightness difference between the two end areas of the elongated highlighted area is greater than a preset brightness difference threshold. If it is greater, determine whether the brightness change from one end to the other end is monotonically increasing or decreasing. If so, it is determined that an arc starting phenomenon has occurred in the power distribution cabinet.

[0045] In this embodiment, specifically, according to the extension direction from one end to the other end, determine the division direction, and divide the elongated highlighted area into multiple sub-areas; The extension direction from one end to the other end follows the bending contour of the long strip-shaped highlighted area. Starting from the starting end, it conforms to the trend of the curve throughout the whole process until reaching the other end. For the convenience of calculation, the extension direction from one end to the other end can also be the straight connection direction from one end to the other end.

[0046] If the angle between the connection line from one end to the other end of the long strip-shaped highlighted area and the horizontal direction is less than 45°, the long strip-shaped highlighted area is vertically divided into multiple sub-regions; If the angle between the connection line from one end to the other end of the long strip-shaped highlighted area and the horizontal direction is greater than 45°, the long strip-shaped highlighted area is horizontally divided into multiple sub-regions; If the angle between the connection line from one end to the other end of the long strip-shaped highlighted area and the horizontal direction is equal to 45°, the long strip-shaped highlighted area is horizontally or vertically divided into multiple sub-regions.

[0047] Among them, the angle between the straight connection direction from one end to the other end of the long strip-shaped highlighted area and the horizontal direction can be represented by the tilt angle The formula for the tangent value of the tilt angle is: , where is the tilt angle, is the tangent value of the tilt angle .

[0048] If the angle between the straight connection direction from one end to the other end of the long strip-shaped highlighted area and the horizontal direction is less than 45°, that is , it indicates that the long strip-shaped highlighted area as a whole tends to extend horizontally. Therefore, the division direction is set to vertical to divide the long strip-shaped highlighted area into multiple sub-regions along its own length direction; similarly, if the angle between the straight connection direction from one end to the other end of the long strip-shaped highlighted area and the horizontal direction is greater than 45°, that is or , it indicates that the long strip-shaped highlighted area as a whole tends to extend vertically. Therefore, the division direction is set to horizontal.

[0049] Using different division methods for long strip-shaped highlighted areas with different angles can divide the long strip-shaped highlighted area into parts along its own length direction, enabling the divided sub-regions to better fit the actual shape of the arc. In this way, when analyzing the brightness distribution, the monotonic change of brightness from one end to the other end and the brightness of the end regions can be captured more accurately, and there will be no detection loopholes due to the diversity of the arc shape, ensuring the accurate determination of the arc starting phenomenon in the power distribution cabinet under various complex conditions.

[0050] As Figure 3 shown Figure 3 is a schematic diagram of dividing a long strip-shaped highlighted area into multiple sub-areas in the horizontal direction.

[0051] In this application, the long strip-shaped highlighted area can be evenly divided into multiple sub-areas, or the image inside the cabinet can be divided into multiple sub-areas along the extension direction from one end to the other end. Each sub-area contains the long strip-shaped highlighted area, so that the long strip-shaped highlighted area is divided into multiple parts. It can also be divided into multiple sub-areas with unequal areas. This application does not specifically limit.

[0052] Figure 3 In (a) of Figure 3 is a schematic diagram where the number of long strip-shaped highlighted targets in each sub-area is 1. In (b) of Figure 3 is a schematic diagram where there are two or more long strip-shaped highlighted targets in the sub-area. When the long strip-shaped highlighted area is spiral, there will be two or more long strip-shaped highlighted targets in the sub-area. In this case, it means that the long strip-shaped highlighted area is not the highlight caused by the arc starting phenomenon, and it may be the highlight caused by other reasons, such as light leakage in the distribution box. Since the characteristic of the arc starting phenomenon is curved but not spiral, when the number of long strip-shaped highlighted targets in each sub-area is 1, it means that the characteristics of the starting arc phenomenon are met, which can exclude some interferences and more accurately judge whether an arc starting phenomenon occurs in the power distribution cabinet.

[0053] Since the arc starting phenomenon usually has a large brightness at the starting arc head and a small brightness at the starting arc tail, when judging whether a suspected starting arc area is actually a starting arc area, it is necessary to detect whether the brightness difference between the two end areas of the suspected starting arc area is greater than the preset brightness difference threshold. If it is greater, it means that the suspected starting arc area meets the condition of a large brightness difference between the starting arc head and the starting arc tail.

[0054] In this embodiment, specifically, the brightness of each end area is any one of the average brightness of each pixel in the end area, the brightness of the pixel at the middle position in the end area, and the brightness of any pixel in the end area. Those skilled in the art can flexibly select the method for determining the brightness of the two end areas.

[0055] For each end area, the average brightness of all pixels in the area can be calculated, and the average brightness of all pixels is determined as the brightness corresponding to the end area. The average brightness value can more accurately and comprehensively reflect the overall brightness situation corresponding to the end area.

[0056] The formula for calculating the average brightness of each pixel in the two end areas is: , ,

[0057] Among them, is the average value of the brightness of the end region corresponding to the head end of, is the average value of the brightness of the end region corresponding to the tail end of, is the number of pixel points in the end region corresponding to the head end is the number of pixel points in the end region corresponding to the tail end is the pixel point index in the end region corresponding to the head end is the pixel point index in the end region corresponding to the tail end is the brightness of, is the brightness of.

[0058] Since the arc starting phenomenon is usually that the brightness gradually decreases from the starting head to the starting tail of the arc, therefore, when judging whether the arc starting phenomenon occurs, it is also necessary to detect that the brightness from one end to the other end is monotonically increasing or decreasing. If it meets the condition, it means that the long and narrow high-brightness region satisfies the condition that the brightness gradually decreases from the starting head to the starting tail of the arc. Among them, if the brightness of the long and narrow high-brightness region gradually decreases from one end to the other end, it means that the starting end is the starting head of the arc and the ending end is the starting tail of the arc; if the brightness of the long and narrow high-brightness region gradually increases from one end to the other end, it means that the starting end is the starting tail of the arc and the ending end is the starting head of the arc.

[0059] In this embodiment, specifically, judging that the brightness from one end to the other end of the long and narrow high-brightness region is monotonically increasing or decreasing includes: Construct a brightness profile line that can go from one end to the other end of the long and narrow high-brightness region, uniformly sample pixel points along the brightness profile line. If the brightness of all sampled pixel points is monotonically increasing or decreasing, then the brightness from one end to the other end of the long and narrow high-brightness region is monotonically increasing or decreasing.

[0060] Among them, the brightness profile line can be any one of a straight line, a broken line, and a curve.

[0061] Optionally, the method for judging that the brightness from one end to the other end of the long and narrow high-brightness region is monotonically increasing or decreasing is: Take the average value of the brightness of each pixel point in each sub-region as the brightness of each sub-region. The formula is: ,

[0062] Among them, is the average brightness of each pixel in the th sub-region, , is the number of pixels in the th sub-region, is the pixel index in the th sub-region, is the brightness of

[0063] Compare the brightness of adjacent sub-regions in sequence according to the extension direction from one end to the other; If the brightness of the subsequent sub-region is always greater than that of the previous sub-region, it is determined that the brightness from one end to the other end of the long and narrow highlighted region is monotonically increasing; if the average brightness of the subsequent sub-region is always less than that of the previous sub-region, it is determined that the brightness from one end to the other end of the long and narrow highlighted region is monotonically decreasing.

[0064] In order to more accurately detect whether the brightness of the long and narrow highlighted region gradually decreases or increases, the number of sub-region divisions can be selected as integers such as 4, 5, 6, 7, 8, 9, 10, etc., but the number of divisions should not be too large to avoid increasing the computational complexity and improving the operation efficiency and the efficiency of anomaly recognition.

[0065] Preferably, the method for determining whether the brightness from one end to the other end of the long and narrow highlighted region is monotonically increasing or monotonically decreasing is: Take the average brightness of each pixel in each sub-region as the brightness of each sub-region; According to the extension direction from one end to the other end, determine the brightness difference between the brightness of the subsequent sub-region and the brightness of the previous sub-region to obtain brightness differences; For example, the long and narrow highlighted region is divided into 4 sub-regions, that is , there is a brightness difference corresponding to the second sub-region and the first sub-region, a brightness difference corresponding to the third sub-region and the second sub-region, and a brightness difference corresponding to the fourth sub-region and the third sub-region, and a total of 3 brightness differences are obtained.

[0066] In this embodiment, the brightness difference between the brightness of the subsequent sub-region and the brightness of the previous sub-region is: the difference obtained by subtracting the brightness of the previous sub-region from the brightness of the subsequent sub-region.

[0067] Count the number of brightness differences greater than 0 and less than 0 among brightness differences, and the formula is: , , where is The number of luminance differences greater than 0 among them, is The number of luminance differences less than 0 among them, is the sub-region index, is the number of sub-regions, is the luminance of the is the luminance of the

[0068] Statistically, the number of luminance differences greater than 0 and less than 0 among them. If the number of luminance differences greater than 0 among them is greater than a preset luminance difference number judgment threshold, it is determined that the luminance from one end to the other end of the long strip-shaped high-brightness region is monotonically increasing; if the number of luminance differences less than 0 among them is greater than a preset luminance difference number judgment threshold, it is determined that the luminance from one end to the other end of the long strip-shaped high-brightness region is monotonically decreasing.

[0069] For example: The long strip-shaped high-brightness region is divided into 4 sub-regions, and the respective luminance values corresponding to the first sub-region to the fourth sub-region are 15, 12, 20, and 25. The three luminance differences are -3, 8, and 5. Among them, the number of luminance differences greater than 0 is 2, and the number of luminance differences less than 0 is 1. If the set luminance difference number judgment threshold is 1.8, and the number of luminance differences greater than 0 among the three luminance differences is greater than 1.8, it is determined that the luminance from one end to the other end of the long strip-shaped high-brightness region is monotonically increasing.

[0070] In practical applications, since the luminance of the arcing image captured in the cabinet may be uneven, and during the arcing phenomenon, the overall arcing light is gradually increasing or decreasing in luminance, but there may be a situation of local luminance flickering. For example, the overall arcing shows a decreasing trend in luminance, but due to the instability of the arcing phenomenon at two adjacent ends, the luminance of the latter region is higher than that of the former region, which does not meet the decreasing trend. In this case, the overall trend should be judged from the overall situation. In this embodiment, when the number of luminance differences greater than 0 among them and the number of luminance differences less than 0 among them, if any one of the numbers is greater than the luminance difference number judgment threshold, it means that the proportion of the number of cases satisfying decreasing or increasing is relatively large, so that the overall trend can satisfy increasing or decreasing. This setting method can well avoid the situation of missing the detection of arcing and improve the accuracy of detecting the arcing phenomenon.

[0071] In this embodiment, optionally, if there is only one long strip-shaped high-brightness region in the cabinet image, end regions corresponding to the two ends of the long strip-shaped high-brightness region are constructed; Divide the long strip-shaped highlighted area into multiple sub-areas, and determine whether the number of long strip-shaped highlighted targets contained in each sub-area is 1. If so, determine whether the brightness difference between the two end areas is greater than the preset brightness difference threshold. If it is greater, determine whether the brightness from one end to the other end is monotonically increasing or decreasing. If so, it is determined that an arc ignition phenomenon has occurred inside the power distribution cabinet.

[0072] Because there may be various factors in the power distribution cabinet that cause highlights in the image. For example, the normal indicator lights turning on, the reflection on the surface of the equipment, etc. may all form highlighted areas, and these situations do not belong to the arc ignition phenomenon. Only when the highlights in the image are completely caused by the arc ignition phenomenon and there is no mixing of highlighted images caused by other reasons, can it be accurately determined that an arc ignition phenomenon has indeed occurred inside the power distribution cabinet. Therefore, taking the premise that there is only one highlight in the cabinet image can effectively avoid misjudgment of the arc ignition phenomenon caused by interference from other irrelevant highlighted images.

[0073] Such as Figure 4 shown, Figure 4 is a schematic flow diagram for the identification of flashover phenomenon.

[0074] Such as Figure 5 shown, Figure 5 is a schematic diagram of the rectangular area where the highlight is identified in the case of an arc ignition phenomenon in the cabinet image.

[0075] In this embodiment, specifically, step S31: After determining that an arc ignition phenomenon has occurred inside the power distribution cabinet, determine whether the aspect ratio of the rectangular area where the highlight is located in the cabinet image after one time sequence is within the range of 0.7 to 1.3, and there is the long strip-shaped highlighted area based on which the arc ignition phenomenon was determined in the previous time sequence. If so, determine whether there is an intersection between the rectangular area where the highlight is located and the long strip-shaped highlighted area based on which the arc ignition phenomenon was determined in the previous time sequence. If there is an intersection, it is determined that an air flow contact arc phenomenon has occurred inside the power distribution cabinet at the current time sequence; When the air flow contacts the burning arc, the air flow will disturb the arc, changing the gas flow field and energy distribution around the arc. In the cabinet image, this disturbance is manifested as a new highlighted area, and the aspect ratio of the rectangular area where the highlighted area is located is within the range of 0.7 to 1.3, and it intersects with the original long strip-shaped highlighted area of the arc. This is because the air flow brings a new energy source or changes the material distribution in the original arc area, resulting in the appearance of highlighted features in the new area and interacting with the original arc area. Therefore, when such image features appear, it can be determined that an air flow contact arc phenomenon has occurred inside the power distribution cabinet.

[0076] Step S32: After determining that there is an air-flow contact arc phenomenon in the power distribution cabinet, determine whether the aspect ratio of the length and width of the highlighted box area in the cabinet image after one time sequence is within a preset range and there is no arc initiation phenomenon in the power distribution cabinet. If so, determine that there is a strong air-flow arc-blowing phenomenon in the power distribution cabinet at the current time sequence; When there is a strong air-flow arc-blowing, the strong air flow will disperse the arc, causing the arc to extinguish. At this time, there will be no new arc initiation phenomenon in the power distribution cabinet. However, the energy of the air flow still exists and will form a highlighted area in the cabinet image, and the aspect ratio of the box area where the highlighted area is located is within a preset range. This is because the air flow may carry substances heated by the arc or the air flow itself interacts with other substances in the power distribution cabinet to produce a light-emitting phenomenon. Therefore, the image feature of a highlighted area with a specific shape appearing without an arc initiation can determine that there is a strong air-flow arc-blowing phenomenon in the power distribution cabinet.

[0077] Step S33: When the power distribution cabinet successively experiences an arc initiation phenomenon, an air-flow contact arc phenomenon, and a strong air-flow arc-blowing phenomenon in three consecutive adjacent time sequences, determine that the power distribution cabinet has a flashover phenomenon.

[0078] Flashover is a gas discharge phenomenon along the insulation surface, usually accompanied by a series of complex physical processes. Arc initiation is the starting stage of flashover. Subsequently, the air flow contacts the arc, causing changes in the arc shape and energy distribution. Finally, the strong air-flow arc-blowing causes the arc to extinguish or the arc energy to be significantly weakened. The sequential occurrence of this series of phenomena reflects the process of energy generation, transfer, and dissipation during flashover. Therefore, when these three phenomena are monitored to occur in sequence, it can be determined that the power distribution cabinet has a flashover phenomenon.

[0079] Among them, the pre-trained highlighted area detection model is used to detect the highlighted box area in the image. The above large area is an area where the maximum circumscribed ellipse of the long strip-shaped highlighted area is close to a circle, that is, the absolute value of the difference between the major axis and the minor axis lengths of the maximum circumscribed ellipse of the long strip-shaped highlighted area is less than a preset first length threshold, and the ratio of the area of the long strip-shaped highlighted area to the area of its maximum circumscribed ellipse is greater than 0.7; or the large area is an area where the maximum circumscribed rectangle of the long strip-shaped highlighted area is close to a square, that is, the absolute value of the difference between the length and the width of the maximum circumscribed rectangle of the long strip-shaped highlighted area is less than a preset second length threshold, and the ratio of the area of the long strip-shaped highlighted area to the area of the maximum circumscribed rectangle is greater than 0.7.

[0080] Among them, for three consecutive adjacent time series, the previous time series and the adjacent next time series are two time series within a preset time duration, that is, the interval between two adjacent time series is within the preset time duration. The preset time duration can be any time duration from 1 second to 5 seconds. Those skilled in the art can set the interval between two adjacent time series according to the specific occurrence duration of flashover. By judging whether three characteristics of arc initiation phenomenon, air flow contacting arc phenomenon, and strong air flow blowing arc phenomenon occur in sequence within the power distribution cabinet for three adjacent time series, it can be accurately judged whether flashover occurs.

[0081] The first embodiment can detect various different types of abnormal situations according to the different displays of the highlighted areas in the cabinet image, and timely send a prompt message to the maintenance personnel according to the situation.

[0082] In this embodiment, it further includes: when it is detected that an arc initiation phenomenon occurs in the power distribution cabinet, an abnormal prompt message is sent to the user terminal device, and the abnormal prompt message is used to indicate the abnormal situation of arc initiation in the power distribution cabinet.

[0083] In practical applications, the fault warning of the power distribution cabinet usually becomes known to the maintenance personnel only after the user reports that the electrical equipment has a fault or the circuit device reports an error. At this time, since the device has already failed, the repair is relatively complex and the repair cost is relatively high. In addition, the impact on the user's power consumption is also relatively large.

[0084] The present invention overcomes the defect that it is difficult to detect the discontinuous arc initiation phenomenon by the existing conventional inspection methods, resulting in the difficulty in timely discovering and preventing equipment failures. By visually identifying the arc initiation phenomenon, it can timely discover potential hazards in the power distribution cabinet, quickly detect abnormalities before the equipment fails, better avoid further failures of the equipment, so as to reduce the repair cost as early as possible and reduce the impact on the user's power consumption.

[0085] The second embodiment of the present application provides a detection system for arc initiation phenomenon in a power distribution cabinet, including: An image acquisition module, configured to acquire an image inside the power distribution cabinet; An end region construction module, configured to construct end regions corresponding to two ends of a long strip-shaped highlighted region when there is a long strip-shaped highlighted region in the cabinet image; A judgment module, configured to divide the long strip-shaped highlighted region into multiple sub-regions, judge whether the number of long strip-shaped highlighted targets included in each sub-region is 1, if so, judge whether the brightness difference between the two end regions of the long strip-shaped highlighted region is greater than a preset brightness difference threshold, and if it is greater, judge whether the brightness change from one end to the other end is monotonically increasing or decreasing. If so, it is determined that an arc initiation phenomenon has occurred in the power distribution cabinet.

[0086] In this embodiment, specifically, the image acquisition module may be a binocular camera, a monocular camera, or other types of cameras. The images inside the power distribution cabinet are captured by installing a camera inside the cabinet. The camera can be magnetically adsorbed or connected to the power distribution cabinet by bolts, clamping, or other connection methods; the number of cameras can be single or multiple, and cameras are installed at multiple positions to capture images inside the power distribution cabinet from different angles, which is not specifically limited in this application.

[0087] Reference Figure 6 , Embodiment 3 of this application also provides a detection device for the arc starting phenomenon in a power distribution cabinet, including: a processor, a memory, a communication bus, and a communication interface; The memory is used to store a computer program, and the processor is used to implement the steps of the above-mentioned method for detecting the arc starting phenomenon in a power distribution cabinet when executing the computer program.

[0088] Embodiment 4 of the present invention provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of the above-mentioned method for detecting the arc starting phenomenon in a power distribution cabinet are implemented.

[0089] Those skilled in the art should understand that the embodiments of this application can be provided as a method, a system, or a computer program product. Therefore, this application can adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, this application can adopt 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 code.

[0090] This application is described with reference to the flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to the embodiments of this application. It should be understood that each flow and / or block in the flowchart and / or block diagram can be implemented by computer program instructions, and the combination of the flows and / or blocks in the flowchart and / or block diagram can also be implemented by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing devices to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing devices generate a device for implementing the specified functions in Figure 1 one process or multiple processes and / or blocks Figure 1 one block or multiple blocks.

[0091] These computer program instructions can also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to work in a particular manner, such that the instructions stored in the computer-readable memory produce a manufacture including an instruction device that implements the functions specified in one or more of the processes and / or blocks Figure 1 one or more of the processes and / or blocks Figure 1 specified in the block or blocks.

[0092] These computer program instructions can also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process, so that the instructions executed on the computer or other programmable apparatus provide steps for implementing the functions specified in one or more of the processes and / or blocks Figure 1 one or more of the processes and / or blocks Figure 1 specified in the block or blocks.

[0093] Obviously, the above embodiments are merely examples for clear illustration and are not limitations on the implementation manners. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to enumerate all the implementation manners here. And the obvious changes or modifications derived therefrom are still within the protection scope of the present invention.

Claims

1. A method for detecting arcing phenomenon in a power distribution cabinet, characterized in that: The following steps are involved: Acquire the image inside the power distribution cabinet, and when there is a long strip of highlighted area in the image inside the cabinet, construct end areas corresponding to the two ends of the long strip of highlighted area; The long strip highlighted area is divided into multiple sub-areas, and it is determined whether the number of long strip highlighted targets contained in each sub-area is 1. If so, it is determined whether the brightness difference between the two end areas of the long strip highlighted area is greater than the preset brightness difference threshold. If so, it is determined whether the brightness change from one end to the other end is monotonically increasing or monotonically decreasing. If so, it is determined that arcing has occurred in the distribution cabinet.

2. The method for detecting arcing phenomenon in a power distribution cabinet according to claim 1, characterized in that: The cabinet image is passed through the pre-trained object detection model to identify the highlighted box area in the cabinet image; It is determined whether the aspect ratio of the box area where the highlight is located in the cabinet image is greater than a preset ratio. If it is greater, it is determined that the highlighted area in the box area where the highlight is located is a long strip, and the highlighted area is extracted to obtain a long strip highlighted area.

3. A method for detecting arcing in a power distribution cabinet according to claim 2, characterized in that: After determining that an arc has occurred in the power distribution cabinet, determine whether there is a highlighted box area with an aspect ratio within a preset range in the image inside the cabinet after an interval of one time sequence. If so, determine whether there is a long strip of highlighted area based on which the arc has been determined in the previous time sequence. If so, determine whether there is an intersection between the highlighted box area and the long strip of highlighted area based on which the arc has been determined in the previous time sequence. If there is an intersection, determine that an airflow contact arc has occurred in the power distribution cabinet in the current time sequence; wherein, the upper limit value of the preset range is less than the preset ratio; After determining that the airflow contacts the arc phenomenon in the power distribution cabinet, determine whether there is a highlighted box area with an aspect ratio within a preset range in the image in the cabinet after an interval of one time sequence. If so, determine whether the arc ignition phenomenon has occurred in the power distribution cabinet of the time sequence. If not, determine that the airflow blows the arc phenomenon strongly in the power distribution cabinet of the time sequence. When arc starting, airflow contacting arc, and strong airflow blowing arc occur in the distribution cabinet in three consecutive adjacent time sequences, it is determined that flashover occurs in the distribution cabinet.

4. The method for detecting arcing phenomenon in a power distribution cabinet according to claim 1, characterized in that: Based on the two end positions of the long strip-shaped highlight region and the average width of the long strip-shaped highlight region, an end region corresponding to each end is constructed.

5. The method for detecting arcing phenomenon in a power distribution cabinet according to claim 4, characterized in that: The process of obtaining the average width of the long strip highlight area includes: According to the direction of the long side of the minimum circumscribed rectangle of the highlight area of ​​the long strip, multiple line segments are drawn at preset intervals through the highlight area of ​​the long strip, and the average value of the distances between the two points where each line segment intersects the boundary of the highlight area of ​​the long strip is calculated as the average width of the highlight area of ​​the long strip.

6. A method for detecting arcing phenomenon in a power distribution cabinet according to claim 5, characterized in that: The step of constructing the end region corresponding to each end based on the two end positions of the long strip highlight region and the average width of the long strip highlight region includes: With each end position as the center and the average width of the long strip highlight area as the side length or diameter, a square area or a circular area is constructed as the end area corresponding to the end.

7. The method for detecting arcing phenomenon in a power distribution cabinet according to claim 1, characterized in that: If the angle between the line from one end to the other end of the long strip highlight area and the horizontal direction is less than 45°, the long strip highlight area is vertically divided into a plurality of sub-areas; If the angle between the line from one end to the other end of the long strip of highlight area and the horizontal direction is greater than 45°, the long strip of highlight area is horizontally divided into a plurality of sub-areas; If the angle between a line from one end to the other end of the long strip of highlight area and the horizontal direction is equal to 45°, the long strip of highlight area is divided horizontally or vertically into a plurality of sub-areas.

8. The method for detecting arcing phenomenon in a power distribution cabinet according to claim 1, characterized in that: If the number of long strip highlighted targets contained in the sub-area of ​​the long strip highlighted area is greater than 1, it is determined that the long strip highlighted area does not meet the conditions of arc starting phenomenon, and no subsequent judgment is performed, and the next long strip highlighted area is processed.

9. The method for detecting arcing phenomenon in a power distribution cabinet according to claim 1, characterized in that: The method for determining whether the brightness from one end of the long strip highlight area to the other end is monotonically increasing or monotonically decreasing includes: The average brightness of each pixel in each sub-region is taken as the brightness of each sub-region; According to the extension direction from one end to the other end of the long strip highlight area, the brightness difference between the brightness of the latter sub-area and the brightness of the former sub-area is determined, and the brightness of the latter sub-area is obtained. brightness difference; among them, is the number of sub-regions; statistics The number of brightness differences greater than 0 and less than 0, if When the number of brightness differences greater than 0 is greater than a preset brightness difference judgment threshold, it is determined that the brightness from one end of the long strip highlight area to the other end is monotonically increasing; if When the number of brightness differences less than 0 is greater than a preset brightness difference judgment threshold, it is determined that the brightness from one end to the other end of the long strip highlight area is monotonically decreasing.

10. A distribution cabinet arcing phenomenon detection system, characterized in that: include: An image acquisition module is used to obtain images inside the power distribution cabinet; An end region construction module, used for constructing end regions corresponding to two ends of a long strip of highlight region when there is a long strip of highlight region in the image inside the cabinet; A judgment module is used to divide the long strip highlighted area into multiple sub-areas, and judge whether the number of long strip highlighted targets contained in each sub-area is 1. If so, it judges whether the brightness difference between the two end areas of the long strip highlighted area is greater than a preset brightness difference threshold. If so, it judges whether the brightness change from one end to the other end is monotonically increasing or monotonically decreasing. If so, it is determined that arcing has occurred in the distribution cabinet.

Images