Power distribution network operation and maintenance inspection method

Abstract

The application discloses a power distribution network operation and maintenance inspection method and relates to the technical field of power distribution network inspection. The method sets regional inspection points, collects images of the inspection equipment at the regional inspection points according to a fixed inspection cycle, calculates the flight height of the inspection equipment and the distance from the tower, obtains a bias coefficient, restores the collected images in a spatial orthogonal coordinate system according to the bias coefficient, obtains the position of the objects in the images, calculates the distance between the position coordinates of the objects and the cables, obtains the foreign matter distance value between the foreign matters and the cables in the inspection area, sets a safety threshold value, compares the safety threshold value with the foreign matter distance value, generates a danger warning signal according to the comparison result, corrects the angle of the inspection area collected by the inspection equipment, and thus the accuracy of fault judgment during the inspection is improved, and the reliability of the inspection equipment is improved.

Description

Technical Field

[0001] This invention belongs to the field of power distribution network inspection technology, specifically a method for power distribution network operation and maintenance inspection. Background Technology

[0002] The power distribution network consists of overhead lines, cables, poles, distribution transformers, disconnect switches, reactive power compensators, and some auxiliary facilities. It plays an important role in distributing electrical energy within the power grid.

[0003] The invention disclosed in patent publication number CN116418110A is a high-efficiency intelligent inspection platform for power distribution network equipment. The equipment detection system field includes an equipment management cloud platform for comprehensive equipment management, an equipment operation management application system, a decoupling service system, an equipment data management data system, an equipment operation status sensing system, an automatic operation and maintenance platform that enables the data system and the sensing system, a network deployment system for platform deployment, application system input and service system output signals connected, service system input and data system output signals connected, data system input end connected to sensing system output signals, and automatic operation and maintenance platform output end electrically connected to the data system and sensing system.

[0004] However, when inspection equipment is used to inspect the power distribution network, the equipment is not perpendicular to the cables during the inspection process. When detecting the distance between foreign objects and cables, the angle of the equipment can cause errors in its judgment. If the foreign object is within the safe distance of the cable, the inspection equipment may not detect the abnormality due to the inspection angle. If the foreign object is not interfered with, it can lead to abnormal cable operation, causing power grid failure or economic losses. Summary of the Invention

[0005] The present invention aims to solve at least one of the technical problems existing in the prior art; to this end, the present invention proposes a distribution network operation and maintenance inspection method to solve the aforementioned technical problem.

[0006] To achieve the above objectives, a distribution network operation and maintenance inspection method is proposed according to an embodiment of the first aspect of the present invention, the method specifically including the following steps: Step 1: Set up regional inspection points, and collect images at the regional inspection points according to a fixed inspection cycle. Calculate the flight altitude of the inspection equipment and the distance to the tower to obtain the offset coefficient. Step 2: Based on the bias coefficient, the acquired image is restored in a spatial rectangular coordinate system, and the distance formula is used to calculate the distance between the foreign object and the cable in the inspection area. Step 3: Set a safety threshold, compare the safety threshold with the distance value of the foreign object, and generate a danger warning signal based on the comparison result.

[0007] As a further aspect of the present invention, the method for setting up regional inspection points is as follows: Once the area distance and area height of the inspection area are obtained, the median of the area distance is taken to find the midpoint between two adjacent towers, and this midpoint is marked as the area inspection point. The inspection area is the area between two adjacent towers.

[0008] As a further aspect of the present invention, the method for obtaining the bias coefficient is as follows: The inspection equipment collects images of the inspection area at the regional inspection points, and at the same time obtains the flight altitude of the inspection equipment; First, subtract the area height from the flight altitude to obtain the vertical distance. The area height refers to the average height of the cable between two adjacent towers. At the same time, obtain the tower distance, which is the distance between the inspection equipment and the tower. Then, a spatial rectangular coordinate system is set up. Based on the position of the tower distance in the spatial coordinate system, the positions of the inspection midpoint and the equipment inspection point are marked respectively. Then, the X-axis coordinates of the equipment inspection point and the inspection midpoint are subtracted to obtain the difference. This difference is then divided by the difference of the Z-axis coordinates of the equipment inspection point and the inspection midpoint. The result is used as the offset coefficient. The inspection midpoint is the position of the cable midpoint.

[0009] As a further aspect of the present invention, the method for obtaining the foreign object distance value is as follows: Once the image acquisition scale B is obtained, the image acquisition scale is first multiplied by the offset coefficient to obtain the image offset value. Then, the image offset value is multiplied by the position coordinates of the inspection midpoint to obtain the reference coordinate point. The distance of the item in the acquired image is substituted into the reference coordinate point to obtain the position of the item in the image in the spatial rectangular coordinate system. Find the location of the object closest to the cable among external objects and mark that object as a foreign object; Then, the position coordinates of both ends of the cable in the inspection area are obtained, and the linear formula is used to calculate and obtain the cable simulation expression of the inspection area; The coordinates of the foreign object are used as input, and the distance is calculated in the cable simulation expression to obtain the distance value of the foreign object.

[0010] As a further aspect of the present invention, the method for obtaining the danger warning signal is as follows: Set a safety threshold. When the distance to the foreign object is less than or equal to the safety threshold, generate a level 1 alarm signal and transmit it to the relevant management personnel. At the same time, mark the corresponding foreign object as the target foreign object. Conversely, when the distance to the foreign object is greater than the safety threshold, do not take any action against it. The target foreign object is then identified to obtain a mobile foreign object. The position coordinates of the mobile foreign object are then calculated to obtain the growth direction angle and growth rate. The growth direction angle and growth rate are calculated to obtain the growth position for the next cycle. The growth position is compared with the danger threshold. When the growth position is less than or equal to the danger threshold, a danger warning signal will be generated. Otherwise, the inspection of moving foreign objects will continue according to the fixed inspection cycle.

[0011] As a further aspect of the present invention, the target foreign object includes movable foreign objects and fixed foreign objects. Movable foreign objects refer to articles that change significantly over time, while fixed foreign objects refer to articles that do not change significantly over time.

[0012] As a further aspect of the present invention, the method for obtaining the growth location is as follows: STE1: Based on the fixed inspection cycle, using the image obtained from the first inspection as the base image, mark the location points of the moving foreign objects in the base image as (Xh1, Yh1, Zh1). STE2: Sequentially acquire the location points of moving foreign objects in each fixed inspection cycle, and identify the location points of moving foreign objects in each fixed inspection cycle in chronological order, and mark them as (Xhj, Yhj, Zhj), j=1, 2, 3, ..., J, indicating that the inspection equipment has collected J images of the inspection area. When j is 1, it is the location point of the moving foreign object in the base image; STE3: Starting with the location point of the active foreign object in the base image, sequentially acquire the location points (Xhj, Yhj, Zhj) in adjacent acquired images. Simultaneously, using the previous active foreign object location point as the base point, calculate the growth direction angle of the active foreign object in each fixed inspection cycle using the arctangent function. ; STE4: Simultaneously, the distance formula is used to calculate the positional distance in adjacent images, and the obtained distance difference is divided by the fixed inspection cycle T to obtain the growth rate Vs; STE5: Then, the growth direction angle and growth rate will be used... The calculation yields the growth position for the next fixed inspection cycle, where... express The angle value of j is taken as J, and Wx is the distance of the movable foreign object from the power distribution network at this time. Compared with the prior art, the beneficial effects of the present invention are: This invention first calculates the offset coefficient between the inspection equipment and the inspection area by using the parameters between the inspection equipment and the cable. Then, it identifies and places the images collected by the inspection equipment according to the offset coefficient. After that, it calculates the vertical distance from the foreign object in the image to the inspection area according to the offset coefficient and corrects the angle of the inspection area collected by the inspection equipment, thereby improving the accuracy of fault judgment during inspection and thus improving the reliability of the inspection equipment. This invention also improves the ability of the power distribution network to predict faults during inspections by monitoring the growth status of plants and judging the distance between the plants and the power distribution network in advance based on their growth direction, thus ensuring the safety of the power distribution network operation. Attached Figure Description

[0013] Figure 1 This is a flowchart of the system framework of the present invention; Figure 2 This is a flowchart of the bias coefficient acquisition process in this invention; Figure 3 This is a flowchart of the danger warning signal acquisition process in this invention. Detailed Implementation

[0014] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0015] Example 1

[0016] Please see Figures 1 to 3 This application provides a method for operation and maintenance inspection of power distribution networks, which specifically includes the following steps: Step 1: Obtain the image map of the distribution network. Starting from the power generation point of the distribution network, obtain the poles and towers in the distribution network in sequence. Then, divide the distribution network according to the poles and towers, that is, set the area between two adjacent poles and towers as the inspection area, and mark the inspection area as i in sequence, i=1, 2, 3, ..., I, indicating that there are I inspection areas in the distribution network. At this time, the number of poles and towers in the distribution network is (I+1). Step 2: Obtain the basic information of the inspection area, including the area distance and area height. Specifically, the area distance refers to the distance between two adjacent towers, and the area height refers to the average height of the cable between two adjacent towers. Then, perform center value processing on each area distance, that is, divide the area distance by 2 to obtain the midpoint of the two adjacent towers. Then mark the midpoint of the two adjacent towers as the area inspection point. The area inspection point corresponds one-to-one with the inspection area. It should be noted that the inspection point here specifically refers to any point on a plane perpendicular to the ground in three-dimensional space where the midpoint of the cable is located. This area inspection point is uncertain, so it is necessary to calculate and obtain the angle between the inspection equipment and the cable. Step 3: First, set a fixed inspection cycle. Then, the inspection equipment inspects the power distribution network according to the fixed inspection cycle time to obtain the tower distance. This distance is then processed to obtain the offset coefficient of the inspection equipment. The fixed inspection cycle is a threshold value, and its specific value is set by a person skilled in the art. In this embodiment, the inspection equipment is a drone. The specific method for obtaining the offset coefficient is as follows: S1: First, with the first area inspection point as the target inspection point, the inspection equipment collects images of the inspection area at the target inspection point; S2: Then, the setting information of the inspection equipment is obtained. The setting information refers to the flight altitude of the inspection equipment and the scale when the inspection equipment collects images. The vertical distance is obtained by subtracting the area height from the flight altitude. Here, the vertical distance is taken as an absolute value. At the same time, the distance between the inspection equipment and the tower is obtained and marked as the tower distance DG. The scale when the equipment collects images is determined by the parameters of the inspection equipment itself. S3: Then, based on the basic information of the inspection area, the setting information of the inspection equipment, and the vertical distance and tower distance, a spatial rectangular coordinate system is established with the ground position of any tower in the inspection area where the target inspection point is located as the origin. At this time, the position of the cable midpoint and the position of the target inspection point where the inspection equipment is located can be obtained. Then, the position of the cable midpoint is marked as the inspection midpoint (X1, Y1, Z1), and the position of the target inspection point is marked as the equipment inspection point (X2, Y2, Z2). It should be noted here that Y1=Y2, that is, the inspection midpoint and the equipment inspection point are the same point on the Y-axis. S4: Then use the formula Obtain the offset coefficients between the equipment inspection points and the inspection midpoint; Step 4: Then, acquire the images collected by the inspection equipment at the inspection points. Based on the image scale, combine the image scale with the offset coefficient to obtain the foreign object distance value. The specific method for obtaining the foreign object distance value is as follows: ST1: Extract the scale of image acquisition from the settings information and mark it as image acquisition scale B. Then, the acquired images are positioned in the spatial rectangular coordinate system according to the image acquisition scale B, that is, the coordinates (X1, Y1, Z1) of the inspection midpoint are obtained. First, the image acquisition scale is multiplied by the offset coefficient to obtain the image offset value. Then, the image offset value is multiplied by the coordinate value of the inspection midpoint to obtain the reference coordinate point. Then, the distance between the items in the acquired image and the inspection midpoint is calculated to obtain the position of each item in the image acquired by the inspection device in the spatial rectangular coordinate system. Finally, the external items in the acquired image are displayed in the spatial rectangular coordinate system according to the obtained coordinate positions. ST2: Using the location of the cable in the inspection area as the central monitoring position, obtain the external object in the image that is closest to the central monitoring position, mark this external object as a foreign object, and obtain the location point of the foreign object (X3, Y3, Z3). ST3: Based on the tower's location coordinates and the area height, obtain the location coordinates (Xd1, Yd1, Zd1) and (Xd2, Yd2, Zd2) of the two ends of the cable in the inspection area, respectively. Then, apply the location coordinates to the linear formula... Calculations are performed to obtain the cable simulation expression, which is then simplified to... , where a, b, c, and d are all proportionality coefficients; ST4: Use a distance formula to compare the location of the foreign object with the cable simulation expression. Calculate the vertical distance from the foreign object to the cable and mark it as the foreign object distance value DY; Step 5: Set a safety threshold and compare it with the distance value of the foreign object. When the distance value is less than or equal to the safety threshold, generate a level 1 alarm signal and transmit it to the relevant management personnel. At the same time, mark the corresponding foreign object as the target foreign object. Conversely, when the distance value is greater than the safety threshold, do not take any action. The safety threshold is set by a professional technician in this field. Then, identify the target foreign object. Based on the identification results, the target foreign object is divided into active foreign objects and fixed foreign objects. Active foreign objects refer to foreign objects that change significantly over time, such as growing plants. Fixed foreign objects refer to items that do not change significantly over time, such as mountains. Step Six: When the identification result shows a fixed foreign object, no processing will be performed. When the identification result shows a moving foreign object, the moving foreign object will be detected to obtain its growth status. An alert signal will be generated based on the growth status, which includes the direction and speed of the moving foreign object's movement.

[0017] Example 2

[0018] This embodiment differs from Embodiment 1 in that the specific method for handling the growth state of the active foreign object in this embodiment is as follows: STE1: Based on a fixed inspection cycle, the image obtained from the first inspection is used as the base image, and the location points of movable foreign objects in the base image are marked as (Xh1, Yh1, Zh1). STE2: Then, the location points of the moving foreign objects in each fixed inspection cycle are obtained sequentially, and the location points of the moving foreign objects in each fixed inspection cycle are identified in chronological order and marked as (Xhj, Yhj, Zhj), j=1, 2, 3, ..., J, indicating that the inspection equipment has collected J images of the inspection area. When j is 1, it is the location point of the moving foreign object in the base image. STE3: Starting with the location point of the moving foreign object in the base image, sequentially acquire the location points (Xhj, Yhj, Zhj) in adjacent acquired images. Simultaneously, using the location point of the previously acquired moving foreign object as the base point, the formula is applied... Calculations were performed to obtain the growth direction angle of the moving foreign object in each fixed inspection cycle. ; STE4: Simultaneously calculates the positional distance between adjacent images using a distance formula. The specific formula for positional distance is as follows: The obtained distance difference is then divided by the fixed inspection cycle T to obtain the growth rate Vs; STE5: The growth direction angle and growth rate are then calculated to obtain the growth position for the next fixed inspection cycle. The specific calculation formula is as follows: ,in express In the equation, j is the angle value when J is taken, and Wx is the distance of the moving foreign object from the power distribution network at this time. Then, the growth position is compared with the danger threshold. When the growth position is less than or equal to the danger threshold, a danger warning signal will be generated and transmitted to the relevant management personnel. Conversely, when the growth position is greater than the danger threshold, the moving foreign object will continue to be inspected according to a fixed inspection cycle. The danger threshold is set by professional technicians in this field.

[0019] Example 3: This embodiment is based on Embodiment 1 and Embodiment 2, but differs from Embodiment 1 and Embodiment 2 in that it combines and implements Embodiment 1 and Embodiment 2.

[0020] The data in the above formula are all calculated by removing the dimensions and taking the numerical values. The formula is the closest to the real situation obtained by software simulation of a large amount of collected data. The preset parameters and preset thresholds in the formula are set by those skilled in the art according to the actual situation or obtained through simulation of a large amount of data.

[0021] The above embodiments are only used to illustrate the technical methods of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical methods of the present invention without departing from the spirit and scope of the technical methods of the present invention.

Claims

1. A method for operation and maintenance inspection of a power distribution network, characterized in that, The method specifically includes the following steps: Step 1: Set up regional inspection points, and collect images at the regional inspection points according to a fixed inspection cycle. Calculate the flight altitude of the inspection equipment and the distance to the tower to obtain the offset coefficient. Step 2: Based on the bias coefficient, the acquired image is restored in a spatial rectangular coordinate system, and the distance formula is used to calculate the distance between the foreign object and the cable in the inspection area. Step 3: Set a safety threshold, compare the safety threshold with the distance value of the foreign object, and generate a danger warning signal based on the comparison result; The method for setting up regional inspection points is as follows: Once the area distance and area height of the inspection area are obtained, the median of the area distance is taken to find the midpoint between two adjacent towers, and this midpoint is marked as the area inspection point. The inspection area is the area between two adjacent towers. The method for obtaining the bias coefficient is as follows: The inspection equipment collects images of the inspection area at the regional inspection points, and at the same time obtains the flight altitude of the inspection equipment; First, subtract the area height from the flight altitude to obtain the vertical distance. The area height refers to the average height of the cable between two adjacent towers. At the same time, obtain the tower distance, which is the distance between the inspection equipment and the tower. Then, a spatial rectangular coordinate system is set up. Based on the position of the tower distance in the spatial coordinate system, the positions of the inspection midpoint and the equipment inspection point are marked respectively. Then, the X-axis coordinates of the equipment inspection point and the inspection midpoint are subtracted to obtain the difference. This difference is then divided by the difference of the Z-axis coordinates of the equipment inspection point and the inspection midpoint. The result is used as the offset coefficient. The inspection midpoint is the position of the cable midpoint. The method for obtaining the distance value of the foreign object is as follows: Once the image acquisition scale B is obtained, the image acquisition scale is first multiplied by the offset coefficient to obtain the image offset value. Then, the image offset value is multiplied by the position coordinates of the inspection midpoint to obtain the reference coordinate point. The distance of the item in the acquired image is substituted into the reference coordinate point to obtain the position of the item in the image in the spatial rectangular coordinate system. Find the location of the object closest to the cable among external objects and mark that object as a foreign object; Then, the position coordinates of both ends of the cable in the inspection area are obtained, and the linear formula is used to calculate and obtain the cable simulation expression of the inspection area; The coordinates of the foreign object are used as input, and the distance is calculated in the cable simulation expression to obtain the distance value of the foreign object.

2. The distribution network operation and maintenance inspection method according to claim 1, characterized in that, The method for obtaining danger warning signals is as follows: Set a safety threshold. When the distance to the foreign object is less than or equal to the safety threshold, generate a level 1 alarm signal and transmit it to the relevant management personnel. At the same time, mark the corresponding foreign object as the target foreign object. Conversely, when the distance to the foreign object is greater than the safety threshold, do not take any action against it. The target foreign object is then identified to obtain a mobile foreign object. The position coordinates of the mobile foreign object are then calculated to obtain the growth direction angle and growth rate. The growth direction angle and growth rate are calculated to obtain the growth position for the next cycle. The growth position is compared with the danger threshold. When the growth position is less than or equal to the danger threshold, a danger warning signal will be generated. Otherwise, the inspection of moving foreign objects will continue according to the fixed inspection cycle.

3. The distribution network operation and maintenance inspection method according to claim 2, characterized in that, The target foreign objects include movable foreign objects and fixed foreign objects. Movable foreign objects refer to items that change significantly over time, while fixed foreign objects refer to items that do not change significantly over time.

4. The distribution network operation and maintenance inspection method according to claim 2, characterized in that, The method for obtaining the growth location is as follows: STE1: Based on the fixed inspection cycle, using the image obtained from the first inspection as the base image, mark the location points of the moving foreign objects in the base image as (Xh1, Yh1, Zh1). STE2: Sequentially acquire the location points of moving foreign objects in each fixed inspection cycle, and identify the location points of moving foreign objects in each fixed inspection cycle in chronological order, and mark them as (Xhj, Yhj, Zhj), j=1, 2, 3, ..., J, indicating that the inspection equipment has collected J images of the inspection area. When j is 1, it is the location point of the moving foreign object in the base image; STE3: Starting with the location point of the active foreign object in the base image, sequentially acquire the location points (Xhj, Yhj, Zhj) in adjacent acquired images. Simultaneously, using the previous active foreign object location point as the base point, calculate the growth direction angle of the active foreign object in each fixed inspection cycle using the arctangent function. ; STE4: Simultaneously, the distance formula is used to calculate the positional distance in adjacent images, and the obtained distance difference is divided by the fixed inspection cycle T to obtain the growth rate Vs; STE5: Then, the growth direction angle and growth rate will be used... The calculation yields the growth position for the next fixed inspection cycle, where... express The angle value of j is taken when J is the value of the moving foreign object, and Wx is the distance between the moving foreign object and the power distribution network at this time.

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