A distribution network ground fault location system and method

Abstract

The present invention discloses a distribution network grounding fault positioning system and method, and relates to the technical field of distribution network fault positioning. The method comprises obtaining a first electrical parameter of each power line in a fault area before a fault occurs and a second electrical parameter after the fault occurs; obtaining an abnormal fluctuation index based on the first electrical parameter and the second electrical parameter; obtaining line data of each power line and power equipment, the line data comprising aging data, historical fault records and historical maintenance records; obtaining an aging index based on the aging data, and obtaining an abnormal fault index based on the historical fault records and the historical maintenance records; obtaining geographic information of the fault area to obtain a power line map; obtaining an abnormal intersection index based on the power line map; obtaining a fault factor of each power line based on the abnormal fluctuation index, the abnormal fault index and the abnormal intersection index; sorting all the fault factors to obtain a line sequence; and performing fault inspection based on the line sequence until the fault point is determined, so as to solve the problems of low accuracy and low efficiency in grounding fault positioning of the distribution network.

Description

Technical Field

[0001] The present invention relates to the technical field of distribution network fault location, and in particular to a distribution network grounding fault location system and method. Background Art

[0002] With the rapid development of modern society, the demand for electricity is growing, and the scale and complexity of distribution networks are also increasing. However, during the operation of distribution networks, grounding faults often occur due to various reasons, such as equipment aging, overload, external interference, etc. Grounding faults not only affect the stable operation of the power system, but may also pose a threat to the safety of equipment and personnel. Therefore, timely and accurate positioning of grounding faults and taking corresponding treatment measures are crucial to ensure the safe and reliable operation of the power system.

[0003] Traditional methods for locating ground faults in distribution networks mainly rely on manual inspections and signal analysis methods. Although manual inspections are intuitive and reliable, they are inefficient and difficult to meet the fault location needs of large-scale distribution networks. Signal analysis methods, such as current method, electromagnetic wave method, and signal injection method, can achieve preliminary positioning of the fault section to a certain extent, but under complex conditions, especially in the early stage of ground faults, the positioning accuracy is often reduced due to insufficient data information or large interference. Summary of the invention

[0004] In order to solve the problem of low accuracy and low efficiency in locating ground faults in a distribution network, the present invention provides a method for locating ground faults in a distribution network, the method comprising:

[0005] Obtain a first electrical parameter of each power line in the fault area before the fault occurs and a second electrical parameter after the fault occurs; obtain an abnormal fluctuation index based on the first electrical parameter and the second electrical parameter; obtain line data of each power line and power equipment, the line data including aging data, historical fault records and historical maintenance records; obtain an aging index based on the aging data, and obtain an abnormal fault index based on the historical fault records and the historical maintenance records; obtain geographic information of the fault area and obtain a power line map; obtain an abnormal intersection point index based on the power line map; obtain a fault factor of each power line based on the abnormal fluctuation index, the abnormal fault index and the abnormal intersection point index; sort all the fault factors to obtain a line sequence; perform fault inspection based on the line sequence until the fault point is determined.

[0006] The principle of the present invention is as follows: by collecting the fluctuation of electrical parameters of power lines before and after a fault occurs, capturing the state change of the power system when a fault occurs, considering the aging conditions of power equipment and power lines, calculating the aging index to evaluate the health status of the equipment, and then determining which equipment may be more prone to failure, so as to give priority to overhauling these equipment and improve the accuracy and efficiency of positioning; combining historical fault records and historical maintenance records, calculating the index of its failure, more accurately identifying power lines with higher fault frequencies, better analyzing the location of the fault, improving the accuracy of fault positioning, and analyzing it, it is possible to discover potential problems and hidden dangers that may exist in the power line in advance, and then taking preventive maintenance measures to reduce the occurrence of faults and improve the reliability and stability of the power system; combining the power line diagram, calculating the abnormal index of its intersection point, the more points where the lines intersect, the more complex the lines are, and the higher the probability of failure, giving priority to overhauling these points, thereby improving the accuracy and efficiency of positioning; from multi-dimensional information such as abnormal fluctuation index, abnormal fault index and abnormal intersection point index, more comprehensively assess the failure risk of the power line, give priority to the lines at the front of the maintenance sequence, thereby improving the accuracy and efficiency of positioning.

[0007] Further, the aging data includes voltage level, line material, operation log, rated operation parameters, usage time, rated usage time and surface damage degree;

[0008] The specific steps of obtaining the aging index include: dividing all the power lines based on the voltage level to obtain several first line classifications, and obtaining a first aging index based on all the first line classifications; dividing all the power lines based on the line material to obtain several second line classifications, and obtaining a second aging index based on all the second line classifications; obtaining real-time operating parameters based on the operation log, and obtaining an error index based on the real-time operating parameters and the rated operating parameters; obtaining a third aging index based on the usage time and the rated usage time; acquiring temperature data and humidity data of each power line based on environmental detection equipment; dividing all the power lines based on the temperature data and the humidity data to obtain several third line classifications, and obtaining a fourth aging index based on all the third line classifications; dividing all the power lines based on the surface damage degree to obtain several fourth line classifications, and obtaining a fifth aging index based on all the fourth line classifications; obtaining the aging index based on the preset weight, the error index, the first aging index, the second aging index, the third aging index, the fourth aging index and the fifth aging index.

[0009] Taking into account the voltage level, line material, operation log, rated operating parameters, usage time, rated usage time and surface damage degree of the lines and equipment, the aging degree is analyzed in multiple dimensions to more accurately assess the health status, thereby improving the accuracy of positioning.

[0010] Furthermore, the specific steps of obtaining the degree of surface damage include: obtaining an original image and a real-time image of each line and power equipment based on an acquisition device, the original image and the real-time image corresponding one to one; respectively obtaining a first pixel value and a second pixel value of the original image and the real-time image, dividing the first pixel value and the second pixel value based on a preset pixel value range, and respectively obtaining a plurality of first regions and a plurality of second regions, the first regions and the second regions corresponding one to one; respectively obtaining a first area of ​​each first region and a second area of ​​each second region; obtaining an area difference based on the first area and the second area, and obtaining the degree of surface damage based on the area difference.

[0011] Compare the images of the lines and equipment after the fault with the original images to obtain the inconsistent areas, and calculate the area to get the degree of damage. The higher the degree of damage, the more likely it is to fail. Priority will be given to repairing those with high degrees of damage, thereby improving the accuracy and efficiency of positioning.

[0012] Furthermore, the specific steps of obtaining the abnormal fault index include: obtaining fault data of each power line based on the historical fault records, the fault data including fault frequency, fault interval duration, fault point, fault type of the fault point and maintenance type of the fault point; obtaining maintenance data of each power line based on the historical maintenance records, the maintenance data including maintenance frequency, maintenance interval duration, maintenance point and maintenance type of the maintenance point; obtaining a first positive and negative factor based on the fault type, the maintenance type and the maintenance type; obtaining a first time factor based on the fault frequency, the fault interval duration, the maintenance frequency and the maintenance interval duration; obtaining the abnormal fault index based on the first positive and negative factors and the first time factor.

[0013] By analyzing the fault type, repair type and maintenance type, the probability of the current equipment and lines failing is calculated. For example, when the repair type is replacement, it is usually difficult for the fault to reoccur within a certain period of time, and the probability is low. The positive and negative factors are negative. When it is only for rust removal, it may fail again due to rust problems, and the positive and negative factors are positive, so as to more accurately assess the probability of failure. By analyzing the frequency and interval length, the fault and maintenance conditions of the power line equipment are analyzed, and then the probability of occurrence within a certain period of time is evaluated, and then the power lines with higher fault frequencies are identified, so as to more accurately assess the probability of failure.

[0014] Furthermore, the specific steps of obtaining the abnormal intersection point index include: obtaining a number of traffic routes in the fault area and the frequency of entry and exit of vehicles on each of the traffic routes; dividing the power line map based on the traffic routes and the frequency of entry and exit of vehicles to obtain a number of first sub-areas, and dividing each of the first sub-areas based on the years of building construction to obtain a number of second sub-areas; obtaining a number of intersections in each of the second sub-areas, and obtaining the number of connecting lines for each of the intersections; and obtaining the abnormal intersection point index based on the number of connecting lines.

[0015] Analyze the traffic routes in the fault area and the frequency of vehicles entering and exiting each traffic route. The higher the frequency, the higher the probability of failure caused by vehicles. The larger the population, the higher the probability of people causing failures. The older the building is and the more damaged it is, the higher the probability of equipment failure. The fault area is divided into detailed parts, and the intersection points of the lines are obtained from them. The more complex the intersection points, the more likely they are to have failures. Therefore, the abnormal intersection point index is calculated, and the probability of failure is more accurately assessed, which can improve the accuracy and efficiency of positioning.

[0016] The frequency of vehicle entry and exit refers to the number of times a vehicle enters and exits within a certain period of time.

[0017] The building construction period refers to the period calculated from the date when the building is completed, accepted and delivered for use.

[0018] Furthermore, the method also includes: obtaining weather data and building height data of the fault area; obtaining wind direction, wind speed and rainfall based on the weather data; obtaining several buildings within a preset height based on the building height data, obtaining the distance between two adjacent buildings, and obtaining a wind outlet building based on the preset distance and the distance; obtaining a wind outlet area based on the wind direction, the wind speed and the wind outlet building, obtaining a first line in the wind outlet area, obtaining a first fault factor based on the first line and the fault factor, and updating the fault factor to the first fault factor.

[0019] Considering the weather such as storms, strong winds can easily blow down the lines or hit the equipment, causing them to fall down. The wind is stronger at the wind outlet, which is more prone to failure. Therefore, the wind outlets formed between high buildings are analyzed to cause damage to the equipment in the wind outlet area. Giving priority to the lines in this area can improve the accuracy and efficiency of positioning.

[0020] Furthermore, the method also includes: determining whether there is a construction area within the fault area, and if so, obtaining a dangerous line based on the construction area, obtaining a second fault factor based on the dangerous line and the fault factor, and updating the fault factor to the second fault factor; otherwise, obtaining traffic data and fire data within the fault area, determining whether there is an accident within the fault area based on the traffic data and the fire data, and if so, obtaining an accident area, obtaining a second line in the accident area, obtaining a third fault factor based on the second line and the fault factor, and updating the fault factor to the third fault factor.

[0021] Considering that construction problems or accidents may cause grounding faults, such as a broken pole caused by a car accident, which in turn causes a broken line, giving priority to line problems in their area can improve positioning accuracy and efficiency.

[0022] Furthermore, the method also includes: obtaining a new line based on the usage time, obtaining several third lines connected to the new line, obtaining a first usage time of each of the third lines based on the usage time, and obtaining several fourth lines based on a preset usage time and the first usage time; obtaining a connection point between the fourth line and the new line, obtaining a fourth fault factor based on the connection point and the fault factor, and updating the fault factor to the fourth fault factor.

[0023] Considering that the connection points of new and old circuits are prone to problems, such as poor contact, unstable wiring and poor sealing, which lead to circuit instability and increase the risk of short circuit and poor contact, giving priority to their connection points can improve positioning accuracy and efficiency.

[0024] Furthermore, the method also includes: obtaining a transformation area and a relocation area within a preset time range, obtaining a fifth line of the transformation area and the relocation area, obtaining a fifth fault factor based on the fifth line and the fault factor, and updating the fault factor to the fifth fault factor.

[0025] Considering the renovation and relocation points during the construction process, due to the lack of unified planning during the initial construction, the lines of multiple units are continuously connected, resulting in chaotic and crisscrossed lines, which are prone to problems such as irregular line laying, disorderly conditions, aging equipment, unreasonable wiring, old circuit configuration unable to meet current electricity demand, and untimely maintenance; giving priority to the line equipment in the renovation and relocation areas can improve the accuracy and efficiency of positioning.

[0026] The present invention also provides a distribution network ground fault location system, the system comprising:

[0027] Abnormal fluctuation unit: used to obtain a first electrical parameter of each power line in the fault area before the fault occurs and a second electrical parameter after the fault occurs; based on the first electrical parameter and the second electrical parameter, obtain an abnormal fluctuation index;

[0028] Abnormal fault unit: used to obtain line data of each power line, the line data including aging data, historical fault records and historical maintenance records; obtain an aging index based on the aging data, and obtain an abnormal fault index based on the historical fault records and the historical maintenance records;

[0029] Abnormal intersection point unit: used to obtain geographical information of the fault area and obtain a power line map; obtain an abnormal intersection point index based on the power line map;

[0030] A fault factor unit: used for obtaining a fault factor of each power line based on the abnormal fluctuation index, the abnormal fault index and the abnormal intersection index;

[0031] Positioning unit: used to sort all the fault factors to obtain a line sequence; perform fault inspection based on the line sequence until the fault point is determined.

[0032] The principle and effect of this system are similar to those of this method, and no corresponding description will be given for this system.

[0033] One or more technical solutions provided by the present invention have at least the following technical effects or advantages:

[0034] 1. By collecting the fluctuation of the operating parameters of the power line before and after the fault occurs, capturing the state change of the power system when the fault occurs, considering the aging of the power equipment and power lines, calculating the aging index to evaluate the health status of the equipment, and then determining which equipment may be more prone to failure, so as to give priority to the maintenance of these equipment and improve the accuracy and efficiency of positioning; combining historical fault records and historical maintenance records, calculating the index of its failure, more accurately identifying the power lines with higher fault frequency, better analyzing the location of the fault, improving the accuracy of fault location, and analyzing it, it can discover the potential problems and hidden dangers that may exist in the power line in advance, and then take preventive maintenance measures to reduce the occurrence of faults and improve the reliability and stability of the power system; combining the power line map, calculating the abnormal index of its intersection point, the more points where the lines intersect, the more complex the lines are, and the higher the probability of failure, giving priority to the maintenance of these points, thereby improving the accuracy and efficiency of positioning; from the multi-dimensional information such as abnormal fluctuation index, abnormal fault index and abnormal intersection index, more comprehensively evaluate the fault risk of the power line, give priority to the lines at the front of the maintenance sequence, thereby improving the accuracy and efficiency of positioning.

[0035] 2. Based on the first line and the fault factor, the first fault factor is obtained. Considering the weather such as storms, the strong wind is easy to blow down the line or blow to the number and then cause it to hang down the line, and the wind is stronger at the wind outlet, which is more likely to cause faults. Therefore, the wind outlet formed between high buildings is analyzed, causing the equipment in the wind outlet area to be damaged, and the lines in this area are given priority, which can improve the accuracy and efficiency of positioning.

[0036] 3. Consider that construction problems or accidents may cause grounding faults, such as a broken pole caused by a car accident, which in turn causes a broken line. Give priority to line problems in their area, which can improve positioning accuracy and efficiency.

[0037] 4. Based on the connection points and fault factors, the fourth fault factor is obtained. Considering that the connection points of the new and old circuits are prone to problems, such as poor contact, unstable wiring and poor sealing, which lead to circuit instability and increase the risk of short circuit and poor contact, giving priority to their connection points can improve the accuracy and efficiency of positioning.

[0038] 5. Obtain the fifth fault factor based on the fifth line and fault factor. Considering the lack of unified planning during the initial construction of the transformation and relocation points, the lines of multiple units are continuously connected, resulting in a chaotic and intertwined line direction, which is prone to problems such as irregular line laying, disorderly conditions, aging equipment, unreasonable wiring, the old circuit configuration cannot meet the current power demand, and untimely maintenance; giving priority to the line equipment in the transformation and relocation areas can improve the accuracy and efficiency of positioning. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The drawings described herein are used to provide a further understanding of the embodiments of the present invention, constitute a part of the present invention, and do not constitute a limitation on the embodiments of the present invention;

[0040] Figure 1 It is a schematic diagram of a flow chart of ground fault location in a distribution network in the present invention. DETAILED DESCRIPTION

[0041] In order to more clearly understand the above-mentioned purpose, features and advantages of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that the embodiments of the present invention and the features in the embodiments can be combined with each other without conflict.

[0042] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those within the scope of this description. Therefore, the protection scope of the present invention is not limited to the specific embodiments disclosed below.

[0043] Embodiment 1

[0044] refer to Figure 1 This embodiment provides a method for locating a ground fault in a distribution network, the method comprising:

[0045] Obtain a first electrical parameter of each power line in the fault area before the fault occurs and a second electrical parameter after the fault occurs; obtain an abnormal fluctuation index based on the first electrical parameter and the second electrical parameter; in this embodiment, the first electrical parameter and the second electrical parameter may include voltage data, current data, and traveling wave data, etc., compare the line data before and after the fault to obtain a change value, and obtain the abnormal fluctuation index through the change value / original value;

[0046] Obtaining line data of each power line and power equipment, the line data including aging data, historical fault records and historical maintenance records; obtaining an aging index based on the aging data, and obtaining an abnormal fault index based on the historical fault records and the historical maintenance records; the aging data including voltage level, line material, operation log, rated operating parameters, service time, rated service time and surface damage degree;

[0047] Among them, the specific steps of obtaining the aging index include: dividing all power lines based on the voltage level to obtain several first line classifications, and obtaining a first aging index based on all the first line classifications; dividing the power lines by different voltage value ranges, and then assigning different aging indices; for example, low-voltage wires are usually used for short-distance power distribution, the lines are shorter, the current is larger, and it is easy to generate more heat, thereby increasing the risk of damage. Low-voltage lines are more susceptible to damage than high-voltage lines, so the aging index assigned to low-voltage lines is greater than the aging index of high-voltage lines.

[0048] Based on the line material, all power lines are divided to obtain several second line classifications, and the second aging index is obtained based on all the second line classifications; the materials of the wires mainly include: conductor materials: copper, aluminum, silver and gold, etc.; insulation materials: PE, NR, chloroprene rubber, nitrile rubber, cable paper and paint, etc.; sheath materials: polyethylene and nylon, etc.; semi-conductive materials: silicon and germanium, etc.; barrier materials: copper wire, copper strip and aluminum strip, etc. The power lines are divided according to different line materials, and different aging indexes are assigned. For example, the surface of aluminum wire is easily oxidized, resulting in overheating of the connection, which in turn causes a fire; and the expansion coefficient of aluminum wire is high, which is easy to cause the connection to loosen, further increasing resistance and heat, forming a vicious cycle, and may eventually cause a fire. Aluminum wire is more easily damaged than copper wire, so the aging index of the aluminum wire line is assigned to be greater than the aging index of the copper wire line.

[0049] The real-time operating parameters are obtained based on the operating log, and the error index is obtained based on the real-time operating parameters and the rated operating parameters. In this embodiment, the real-time operating parameters and the rated operating parameters may be power, electric energy, resistance, etc., and the error index is obtained by calculating the numerical difference between the two and dividing the numerical difference by the rated operating parameters.

[0050] A third aging index is obtained based on the usage time and the rated usage time; if the rated usage time of the line is 10 years and the usage time is 3 years, then 3 / 10=0.3, and the third aging index is obtained.

[0051] Based on the environmental detection equipment, the temperature data and humidity data of each power line are obtained; based on the temperature data and the humidity data, all the power lines are divided to obtain a number of third line classifications, and the fourth aging index is obtained based on all the third line classifications; in this embodiment, the environmental detection equipment can be an infrared thermal imager, an optical fiber sensor, an electrical sensor, a humidity sensor, a capacitive sensor, etc. By dividing the temperature data and the humidity data into ranges, different aging indexes are assigned; if the lines with high temperature and high humidity are more easily damaged, the maximum aging index is assigned.

[0052] All power lines are divided based on the surface damage degree to obtain a number of fourth line classifications, and a fifth aging index is obtained based on all the fourth line classifications; the surface damage degree is divided into ranges and different aging indices are allocated.

[0053] Based on the preset weight, the error index, the first aging index, the second aging index, the third aging index, the fourth aging index and the fifth aging index, the aging index is obtained, such as a*error index+b*first aging index+c*second aging index+d*third aging index+e*fourth aging index+f*fth aging index, where a, b, c, d, e and f all represent weight coefficients.

[0054] The specific steps of obtaining the surface damage degree include:

[0055] Based on the acquisition device, an original image and a real-time image of each line and power equipment are acquired, and the original image and the real-time image correspond to each other one by one;

[0056] Acquire a first pixel value and a second pixel value of the original image and the real-time image respectively, divide the first pixel value and the second pixel value based on a preset pixel value range, and obtain a plurality of first regions and a plurality of second regions respectively, wherein the first regions correspond to the second regions one by one; and acquire a first area of ​​each of the first regions and a second area of ​​each of the second regions respectively;

[0057] An area difference is obtained based on the first area and the second area, and the surface damage degree is obtained based on the area difference.

[0058] The specific steps of obtaining the abnormal fault index include:

[0059] Obtaining fault data of each power line based on the historical fault records, the fault data including fault frequency, fault interval duration, fault point, fault type of the fault point and maintenance type of the fault point;

[0060] Obtaining maintenance data of each power line based on the historical maintenance records, the maintenance data including maintenance frequency, maintenance interval duration, maintenance point, and maintenance type of the maintenance point;

[0061] A first positive and negative factor is obtained based on the fault type, the repair type and the maintenance type; the fault type may include poor contact, short circuit, open circuit, aging or corrosion of the insulation layer, joint problem, wire cracking and breakdown fault, etc., the repair type may include replacement and repair, etc., and the maintenance type may include cleaning, detection, replacement and repair, etc. If the fault type is poor contact and the repair type is repair, the probability of the line having poor contact again is high, and the positive and negative factor is positive; if the fault type is wire cracking and the repair type is replacement, the probability of the line cracking again is low, and the positive and negative factor is negative.

[0062] A first time factor is obtained based on the fault frequency, the fault interval duration, the maintenance frequency and the maintenance interval duration; if the fault frequency and the maintenance frequency are divided into ranges, the higher the frequency, the higher the assigned value; if the fault interval duration and the maintenance interval duration are divided into the same ranges, the longer the interval duration, the smaller the assigned value; and then different weight coefficients are assigned to the frequency and the interval duration, so as to obtain the time factor.

[0063] The abnormal fault index is obtained based on the first positive and negative factors and the first time factor. For example, different weight coefficients are assigned to the positive and negative factors and the time factor. When the positive and negative factors are positive, the abnormal fault index = A*q + B*p, and when the positive and negative factors are negative, the abnormal fault index = -A*q + B*p, where A and B represent the positive and negative factors and the time factor, respectively, and q and p represent the weight coefficients, thereby obtaining the time factor.

[0064] Obtaining geographic information of the fault area and obtaining a power line map; obtaining an abnormal intersection point index based on the power line map;

[0065] The specific steps of obtaining the abnormal intersection index include:

[0066] Acquire a number of traffic routes in the fault area and the frequency of traffic vehicles entering and exiting each of the traffic routes;

[0067] Based on the traffic lines and the frequency of entry and exit of the vehicles, the power line map is divided to obtain a number of first sub-areas, and based on the years of construction of the houses, each of the first sub-areas is divided to obtain a number of second sub-areas; a number of intersections of each of the second sub-areas is obtained, and the number of connecting lines of each of the intersections is obtained;

[0068] The abnormal intersection index is obtained based on the number of connecting lines. For example, the areas of each traffic line are divided according to different ranges of the frequency of entry and exit of vehicles, and then divided again according to different ranges of the years of housing construction, the intersection of lines in each area is obtained, the number of lines at each intersection is calculated, and the abnormal intersection index is obtained according to the number.

[0069] Based on the abnormal fluctuation index, the abnormal fault index and the abnormal intersection index, the fault factor of each power line is obtained; such as x*abnormal fluctuation index+y*abnormal fault index+z*abnormal intersection index=fault factor, x, y and z are all different weight coefficients.

[0070] All the fault factors are sorted to obtain a line sequence; and fault inspection is performed based on the line sequence until the fault point is determined.

[0071] Embodiment 2

[0072] On the basis of the first embodiment, in this embodiment, the method further includes:

[0073] Obtain weather data and building height data of the fault area; obtain wind direction and wind speed based on the weather data; such as obtaining wind direction and wind speed through an anemometer and ultrasonic anemometer;

[0074] Based on the building height data, several buildings within a preset height are obtained, the distance between two adjacent buildings is obtained, and the wind outlet building is obtained based on the preset distance and the distance; if a building with a height greater than 50m is obtained, it is determined whether the distance between the two adjacent buildings is less than the preset distance, and if so, the two buildings are regarded as wind outlet buildings;

[0075] Based on the wind direction, the wind speed and the wind outlet building, a wind outlet area is obtained, a first line in the wind outlet area is obtained, and based on the first line and the fault factor, a first fault factor is obtained, and the fault factor is updated to the first fault factor. If it is determined whether the wind speed is greater than the preset wind speed, if so, the wind outlet area between the wind outlet buildings is determined according to the wind direction, the lines in the area are obtained, and the fault factor is recalculated, such as 1+fault factor*i, where i represents a weight coefficient.

[0076] Embodiment 3

[0077] Based on the above embodiment, in this embodiment, the method further includes:

[0078] Determine whether there is a construction area in the fault area. If so, obtain a dangerous line based on the construction area, obtain a second fault factor based on the dangerous line and the fault factor, and update the fault factor to the second fault factor; such as 1+fault factor*j, where j represents a weight coefficient.

[0079] If not, traffic data and fire data in the fault area are obtained, and based on the traffic data and the fire data, it is determined whether there is an accident in the fault area, and if so, the accident area is obtained, a second line of the accident area is obtained, and a third fault factor is obtained based on the second line and the fault factor, and the fault factor is updated to the third fault factor, such as 1+fault factor*k, where k represents a weight coefficient.

[0080] Embodiment 4

[0081] Based on the above embodiment, in this embodiment, the method further includes:

[0082] A new line is obtained based on the usage time, several third lines connected to the new line are obtained, a first usage time of each of the third lines is obtained based on the usage time, and several fourth lines are obtained based on a preset usage time and the first usage time; a connection point between the fourth line and the new line is obtained, a fourth fault factor is obtained based on the connection point and the fault factor, and the fault factor is updated to the fourth fault factor.

[0083] For example, obtain a new line that has been in use for less than 6 months, obtain the line connected to it, obtain the old line that has been in use for more than 3 years, obtain the connection point between the new line and the old line, and recalculate the failure factor of the point, such as 1+failure factor*m, where m represents the weight coefficient.

[0084] Embodiment 5

[0085] Based on the above embodiment, in this embodiment, the method further includes:

[0086] Obtain the renovation area and relocation area within a preset time range, such as obtaining the renovation area and relocation area within one year, obtain the fifth line of the renovation area and the relocation area, obtain the fifth fault factor based on the fifth line and the fault factor, and update the fault factor to the fifth fault factor. For example, 1+fault factor*n, where n represents the weight coefficient

[0087] Embodiment 6

[0088] This embodiment also provides a distribution network ground fault location system, the system comprising:

[0089] Abnormal fluctuation unit: used to obtain a first electrical parameter of each power line in the fault area before the fault occurs and a second electrical parameter after the fault occurs; based on the first electrical parameter and the second electrical parameter, obtain an abnormal fluctuation index;

[0090] Abnormal fault unit: used to obtain line data of each power line, the line data including aging data, historical fault records and historical maintenance records; obtain an aging index based on the aging data, and obtain an abnormal fault index based on the historical fault records and the historical maintenance records;

[0091] Abnormal intersection point unit: used to obtain geographical information of the fault area and obtain a power line map; obtain an abnormal intersection point index based on the power line map;

[0092] A fault factor unit: used for obtaining a fault factor of each power line based on the abnormal fluctuation index, the abnormal fault index and the abnormal intersection index;

[0093] Positioning unit: used to sort all the fault factors to obtain a line sequence; perform fault inspection based on the line sequence until the fault point is determined.

[0094] Although the preferred embodiments of the present invention have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0095] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A method for locating ground faults in a distribution network, characterized in that: The method comprises: Obtaining a first electrical parameter of each power line in the fault area before the fault occurs and a second electrical parameter after the fault occurs; obtaining an abnormal fluctuation index based on the first electrical parameter and the second electrical parameter; Acquire line data of each power line and power equipment, wherein the line data includes aging data, historical fault records, and historical maintenance records; obtain an aging index based on the aging data, and obtain an abnormal fault index based on the historical fault records and the historical maintenance records; Obtaining geographic information of the fault area and obtaining a power line map; obtaining an abnormal intersection index based on the power line map; Based on the abnormal fluctuation index, the abnormal fault index and the abnormal intersection index, obtaining a fault factor of each power line; All the fault factors are sorted to obtain a line sequence; and fault inspection is performed based on the line sequence until the fault point is determined.

2. A method for locating a ground fault in a distribution network according to claim 1, characterized in that: The aging data includes voltage level, line material, operation log, rated operation parameters, usage time, rated usage time and surface damage degree; The specific steps to obtain the aging index include: Dividing all power lines based on the voltage level to obtain a plurality of first line classifications, and obtaining a first aging index based on all the first line classifications; Dividing all power lines based on the line material to obtain a plurality of second line categories, and obtaining a second aging index based on all the second line categories; obtaining a real-time operating parameter based on the operating log, and obtaining an error index based on the real-time operating parameter and the rated operating parameter; A third aging index is obtained based on the usage time and the rated usage time; (usage time / rated usage time) temperature data and humidity data of each power line are obtained based on the environmental detection device; all power lines are divided based on the temperature data and the humidity data to obtain a plurality of third line classifications, and a fourth aging index is obtained based on all the third line classifications; Dividing all power lines based on the surface damage degree to obtain a plurality of fourth line classifications, and obtaining a fifth aging index based on all the fourth line classifications; The aging index is obtained based on a preset weight, the error index, the first aging index, the second aging index, the third aging index, the fourth aging index, and the fifth aging index.

3. A method for locating ground faults in a distribution network according to claim 2, characterized in that: The specific steps of obtaining the surface damage degree include: Based on the acquisition device, an original image and a real-time image of each line and power equipment are acquired, and the original image and the real-time image correspond to each other one by one; Acquire a first pixel value and a second pixel value of the original image and the real-time image respectively, divide the first pixel value and the second pixel value based on a preset pixel value range, and obtain a plurality of first regions and a plurality of second regions respectively, wherein the first regions correspond to the second regions one by one; and acquire a first area of ​​each of the first regions and a second area of ​​each of the second regions respectively; An area difference is obtained based on the first area and the second area, and the surface damage degree is obtained based on the area difference.

4. A method for locating ground faults in a distribution network according to claim 1, characterized in that: The specific steps of obtaining the abnormal fault index include: Obtaining fault data of each power line based on the historical fault records, the fault data including fault frequency, fault interval duration, fault point, fault type of the fault point and maintenance type of the fault point; Obtaining maintenance data of each power line based on the historical maintenance records, the maintenance data including maintenance frequency, maintenance interval duration, maintenance point and maintenance type of the maintenance point; obtaining a first positive and negative factor based on the fault type, the repair type and the maintenance type; Obtaining a first time factor based on the fault frequency, the fault interval duration, the maintenance frequency, and the maintenance interval duration; The abnormal fault index is obtained based on the first positive and negative factors and the first time factor.

5. A method for locating ground faults in a distribution network according to claim 1, characterized in that: The specific steps to obtain the abnormal intersection index include: Acquire a number of traffic routes in the fault area and the frequency of traffic vehicles entering and exiting each of the traffic routes; Based on the traffic lines and the frequencies of entry and exit of the vehicles, the power line map is divided to obtain a plurality of first sub-areas, and based on the years of construction of the houses, each of the first sub-areas is divided to obtain a plurality of second sub-areas; Obtain a number of intersection points of each of the second sub-areas, and obtain the number of connection lines of each of the intersection points; The abnormal intersection index is obtained based on the number of connecting lines.

6. A method for locating ground faults in a distribution network according to claim 1, characterized in that: The method further comprises: Acquire weather data and building height data of the fault area; obtain wind direction and wind speed based on the weather data; Based on the building height data, a number of buildings within a preset height are obtained, a distance between two adjacent buildings is obtained, and a vent building is obtained based on the preset distance and the distance; A vent area is obtained based on the wind direction, the wind speed and the vent building, a first line of the vent area is acquired, a first fault factor is obtained based on the first line and the fault factor, and the fault factor is updated to the first fault factor.

7. A method for locating ground faults in a distribution network according to claim 1, characterized in that: The method further comprises: Determine whether there is a construction area in the fault area, if so, obtain a dangerous line based on the construction area, obtain a second fault factor based on the dangerous line and the fault factor, and update the fault factor to the second fault factor; Otherwise, traffic data and fire data in the fault area are obtained, and based on the traffic data and the fire data, it is determined whether there is an accident in the fault area; if so, the accident area is obtained, a second line of the accident area is obtained, a third fault factor is obtained based on the second line and the fault factor, and the fault factor is updated to the third fault factor.

8. A method for locating ground faults in a distribution network according to claim 2, characterized in that: The method further comprises: A new line is obtained based on the usage time, several third lines connected to the new line are obtained, a first usage time of each of the third lines is obtained based on the usage time, and several fourth lines are obtained based on a preset usage time and the first usage time; a connection point between the fourth line and the new line is obtained, a fourth fault factor is obtained based on the connection point and the fault factor, and the fault factor is updated to the fourth fault factor.

9. A method for locating ground faults in a distribution network according to claim 1, characterized in that: The method further comprises: Acquire a transformation area and a relocation area within a preset time range, acquire fifth lines of the transformation area and the relocation area, obtain a fifth fault factor based on the fifth line and the fault factor, and update the fault factor to the fifth fault factor.

10. A distribution network ground fault location system, characterized in that: The system comprises: Abnormal fluctuation unit: used to obtain a first electrical parameter of each power line in the fault area before the fault occurs and a second electrical parameter after the fault occurs; based on the first electrical parameter and the second electrical parameter, obtain an abnormal fluctuation index; Abnormal fault unit: used to obtain line data of each power line, the line data including aging data, historical fault records and historical maintenance records; obtain an aging index based on the aging data, and obtain an abnormal fault index based on the historical fault records and the historical maintenance records; Abnormal intersection point unit: used to obtain geographical information of the fault area and obtain a power line map; obtain an abnormal intersection point index based on the power line map; A fault factor unit: used for obtaining a fault factor of each power line based on the abnormal fluctuation index, the abnormal fault index and the abnormal intersection index; Positioning unit: used to sort all the fault factors to obtain a line sequence; perform fault inspection based on the line sequence until the fault point is determined.

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