Method, system, device and storage medium for locating short circuit fault sections of oilfield distribution networks

GB2621696BActive Publication Date: 2025-07-02CHINA UNIV OF PETROLEUM (EAST CHINA)
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Patent Information

Application Number
GB2023010805
Authority / Receiving Office
GB · GB
Patent Type
Patents
Current Assignee / Owner
Priority Date
2022-08-11
Filing Date
2023-07-13
Publication Date
2025-07-02
Estimated Expiration
2043-07-13

AI Technical Summary

Technical Problem

Existing fault location methods in oilfield distribution networks are costly, require high information synchronization, and have low accuracy, especially for short-circuit faults, as they need phase measurement and additional monitoring facilities, and are slow in locating faults due to manual processes and complex network structures.

Method used

A method and system that utilize load-side line voltage amplitudes to determine short-circuit fault sections without phase measurement or additional monitoring, using existing load-side monitoring terminals to measure line voltage amplitudes before and after faults, combining network topology and fault phase selection results to identify fault locations quickly and accurately.

Benefits of technology

This approach reduces the complexity and cost of fault location, improves accuracy, and speeds up the process of identifying short-circuit faults between adjacent load-side measuring nodes, enhancing the reliability of power supply systems and reducing economic losses in oilfield production.

✦ Generated by Eureka AI based on patent content.

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Abstract

A method for locating short circuit fault sections of oilfield distribution networks comprises: S101 - using load-side measuring terminals to measure line voltage amplitudes of nodes in a system befor
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Description

Description Method, system, device and storage medium for locating short circuit fault sections of oilfield distribution networks Technical Field The present invention belongs to the technical field of power distribution network fault data identification, in particular to a method, a system, a device and a storage medium for locating short circuit fault sections of oilfield distribution networks. Background Technology Oilfield distribution networks are located at ends of power supply systems, directly facing electrical equipment, and are key links to ensure reliability of power supply and improve economical operation. With the development of the oil industry, the demand for electricity is increasing. However, due to the practical problems such as geography, climate and so on, there are many faults in the distribution lines of China's oilfield power grid in practical applications, which not only has negative effects on actual production, but also causes certain economic losses. The fault location systems can accurately locate fault sections and fault types, and quickly realize maintenance and emergency repair, which is conducive to improving the reliability and efficiency of the power supply of the oil field grid, thereby improving the overall power supply quality of the oil field grid and increasing economic returns. The vast majority of oil field distribution networks are powered by single power radial networks with characteristics like long lines, wide distribution areas, complex line construction, many branch lines, scattered loads, unstable line structures, too fast changes and so on. In traditional fault judgment processes, most distribution networks adopt methods of line-by-line power outage to determine faulty lines, when faulty lines are selected, line patrol workers are sent to the sites to find fault locations along lines, and then isolate and remove faults; due to the manual participation of such methods, the locating time required is quite long, and the time consumed by the methods is much longer than the time spent on repairing faults, resulting in a long power outage; in addition, it generally requires all line power outage for line maintenance, which has a great impact on oil field production. In recent years, the rapid development of intelligent distribution networks has provided technical supports for solving existing problems of oilfield power grids. The fault location algorithm based on FTU (feeder terminal unit) can realize rapid isolation of faults, reduce the influence of faulty lines on sound lines, and narrow the scope of power failure, which has good application value for oil fields with huge economic losses once power failure occurs. Through the above analysis, the existing problems and defects of the prior art are as follows: Description 1. In the existing technology, fault location based on FTU needs high cost, and has high requirements on information synchronization, and the fault location accuracy thereof is low. 2. In the prior art, when locating the sections where faults occur, it is necessary to measure the phases and add additional monitoring facilities; when judging the types of short-circuit faults and locating the locations of the faults, the fault location cannot be as accurate as to adjacent load-side measuring nodes, and the locating speeds thereof are slow. 3. At present, transformers in 10kV oilfield distribution networks generally adopt a DY connection method, and neutral points on load sides are not grounded, so phase voltage data cannot be measured on load sides. Summary of the Invention To overcome problems in related technologies, embodiments of the present invention provides a method, a system, a device and a storage medium for locating short circuit fault sections of oilfield distribution networks, and specifically relates to a method and a system for locating short circuit fault sections of oilfield distribution networks based on load-side line voltage amplitudes. Based on the above oilfield distribution network fault location background, the purpose of the present invention is to obtain line voltage amplitudes of load sides before and after short circuit faults by using oilfield load side measuring terminals, and according to the network topology structure and load distribution, in combination with fault phase selection results, horizontal comparison of load-side line voltage distribution law, to determine short circuit fault sections of distribution networks. The present invention is based on line voltage amplitudes before and after the fault on a load side measured by monitoring terminals, uses limited information, does not need to measure the phase, does not need to add additional monitoring facilities, combines line parameters and fault phase selection results, realizes locating of short circuit fault sections, reduces the difficulty of applying the fault location method in oilfield distribution networks, and improves the fault location speed of the oilfield distribution networks. The present invention has following technical solutions: A method for locating short circuit fault sections of oilfield distribution networks based on load-side line voltage amplitudes comprises the steps of: S1-on a basis of distribution characteristics of load-side line voltage amplitudes when a short circuit fault occur at medium-voltage sides, using line voltage amplitudes of load-side measuring nodes to determine a type and a phase of the short circuit fault; Description S2-according to a short circuit fault phase selection result, when a two-phase short circuit is determined, using measured line voltage amplitudes of the load-side measuring nodes to calculate magnitudes of positive sequence current fault components at medium-voltage sides, determining a fault occurring section and identifying fault location based on distribution characteristics of calculated positive sequence current fault components at medium-voltage sides; and S3-according to the short circuit fault phase selection result, when a three-phase short circuit is determined, horizontally comparing line voltage amplitude differences of adjacent load-side measuring nodes, determining the fault occurring section and identifying fault location based on distribution characteristics of calculated line voltage amplitude differences of adjacent the load-side measuring nodes. In an embodiment of the present invention, in the S1, when load-side monitoring terminal data meets startup criteria, if line voltage amplitudes of three phases at an any load-side measuring node i are equal, a three-phase short circuit fault is judged to have occurred in a system; wherein if a line voltage amplitude of any load-side measuring node i between phase A and phase B remains constant before and after the short circuit fault, a BC two-phase short circuit fault is judged to have occured in the system; and if a line voltage amplitude of any load-side measuring node i between phase C and phase A remains constant before and after the short circuit fault, an AB two-phase short circuit fault is judged to have occured in the system. In an embodiment of the present invention, when the BC two-phase short circuit fault occurs, there are following expressions related to the line voltage amplitude of any load-side measuring node i between phase B and phase C: 11 n n l= [5] [a+ Bl 20) — [hE] PEs) n i represents any load-side measuring node, Us, Un, and Vir respectively refer to three phase voltages before a medium-voltage side node fault, n represents a . " Z transformation ratio of transformers. “7 represents a mutual impedance transformation ratio of transformers, “” represents a mutual impedance ! ’ | Lo between any load-side measuring node and a fault point, and represents a Description fault current; a voltage of any load-side measuring nodes in normal operation is obtained via an AB load-side line voltage amplitude after fault, let a voltage of phase A before fault be a zero phase, and three phase voltages before fault are obtained according to the voltage of phase A before fault; and the transformation ratio of transformers is known while a product of mutual impedance Zs and the I #40 is regarded as a variable, which is defined as ol ang 1d for any load-side measuring node, load-side line voltage amplitudes are taken as dependent variables, and an amplitude and a phase of AU, are taken pol 2500) as independent variables to generate two equations: n Io..| [EC ~ 3a, and n I, so as to correspondingly solve two variables, and 7 1, so as to correspondingly solve two variables, ' AU, _— the amplitude and the phase of ¥. and based on load-side line voltage AU, AU,, amplitudes, Ally 8h, ,.. and AU, of all load-side measuring nodes in the system are obtained correspondingly; and AU, ~~ ¥ corresponding to any two adjacent load-side measuring nodes are reduced to 1,,(Z, =Zir) mals a crmltama Aiffaranca latisiaam ams farm adiarant laad cide AEE namely a voltage difference between any two adjacent load-side measuring nodes when a positive sequence fault current flows into a fault point; a voltage difference between two adjacent load-side measuring nodes m and nis defined as AU, and when voltage differences AU, between all sections are obtained, in combination with line topology and line parameters, positive sequence current fault components between all sections are obtained by dividing AU, with line impedances between m and n. In an embodiment of the present invention, in the S2 of determining the fault occurring section and identifying fault location based on the distribution characteristics of calculated positive sequence current fault components at medium-voltage sides when a two-phase short circuit is determined, a voltage of a load-side measuring node n is equal to a voltage of a fault point f, Description AU, =AU,-AU, = AU, - ,—AU, = AU, and let a calculated value of the positive ir sequence current fault component at a section mn be Ly , then following formulas I or, - __AU, AU, : a a a ry mn are derived: Am tly Ly tly l= Lu, and Tue =O, based on the distribution characteristics, two-phase short circuit locating criteria for a branchless line are as follows: among all the sections which are less than 10% of a positive sequence current fault component at a head end of the branchless line, and an upstream section closet to a power point section is a fault-occurring section; if no section meets conditions and a positive sequence current fault component at a tail end of the branchless line is smaller than positive sequence current fault components at upstream sections, the tail end section of the branchless line is the fault occurring section; according to above fault locating analysis for the branchless line, positive sequence current fault components of sections are obtained via load-side line voltage i ~] wl. wl. 3 LW 3 amplitudes, wherein 4 Lp 1y I Ion 0 aid Ly <1, <n, based on the distribution characteristics, two-phase short circuit locating criteria for a main line with branch lines are as follows: firstly, applying locating criteria for branchless lines to the main line and judging where a fault occurs, if there is no branch line downstream of a faulty section, locating the fault section as the fault occurring section; if a branch line exists downstream of the fault section, taking a power source point as a starting point and a tail end node of the branch line as an end point, applying the two-phase short circuit locating criteria for branchless lines and judging where the fault occurs, if the fault section is judged to be same as the main line, then locating the fault section as the fault occurring section; and if it is judged that there is still a branch line downstream of the fault occurring section, repeating above process until there is no branch line downstream of a positioned section. In an embodiment of the present invention, in the S3, when the three-phase short circuit occurs, the load-side line voltage amplitudes decrease monotonically from a power source point to a fault point, based on a distribution law, line voltage amplitudes of load-side measuring nodes are measured, voltage drops caused by loading currents are taking into account, and three-phase short circuit locating criteria are as follows: calculating absolute values of subtraction of line voltage amplitudes at adjacent load-side measuring nodes, locating sections where branch lines first appear to have voltages smaller than a set value, and determining an upstream section farthest from a section of a power source point among positioned Description sections to be the fault occurring section. Another purpose of the present invention is to provide a system for locating short circuit fault sections of oilfield distribution networks based on the method for locating short circuit fault sections of oilfield distribution networks, comprising: a fault location startup module configured to record load-side line voltage amplitudes, and start fault location process when a sudden change of a line voltage is greater than a set value; a fault type judgment moduleconfigured to judge fault types via line voltage amplitudes before and after faults, and determine fault phases when two-phase short circuit faults occur in the system; a section location module for two-phase short circuit faults configured to calculate positive sequence current fault components at medium-voltage sides via load-side line voltages, and determine sections where the two-phase short circuit faults occur based on distribution characteristics of calculated positive sequence current fault components at medium-voltage sides; and a section location module for three-phase short circuit faults configured to horizontally compare line voltage amplitude differences of adjacent load-side measuring nodes, and determine sections where the three-phase short circuit faults occur based on distribution characteristics of calculated load-side line voltage amplitude differences. In an embodiment of the present invention, the system for locating short circuit fault sections of oilfield distribution networks further comprises a master station and load-side monitoring terminals, wherein the load-side monitoring terminals determine fault type and fault phase data based on monitored characteristics of line voltage amplitudes of load-side measuring nodes before and after a fault, and upload determined fault type and fault phase data to the master station; when a short circuit fault occurs at a medium voltage side, a voltage of the system drops until a line voltage amplitude of a load-side measuring node drops to 90% of a rated voltage, the fault location process is started and simultaneously two cycles at a T after a moment of failure and a 7, before the moment of failure are read as calculation data for fault phase selection and fault location. Another purpose of the present invention is to provide a computer device comprising a memory and a processor, wherein the memory stores computer program, when the computer program is executed by the processer, the processor executes the method for locating short circuit fault sections of oilfield distribution networks. Description Another purpose of the present invention is to provide a computer-readable storage medium storing a computer program, and when the computer program is executed by the processer, the processor executes the method for locating short circuit fault sections of oilfield distribution networks. Another purpose of the present invention is to provide a feeder line terminal unit for locating short circuit fault sections of oilfield distribution networks, wherein the feeder line terminal unit is configured to be executed on an electronic device and provide a user input interface to implement the method for locating short circuit fault sections of oilfield distribution networks. Combining all the above technical solutions, the present invention has following advantages and positive effects: Firstly, in view of technical problems existing in the prior art and difficulties of solving the technical problems, in combination with technical solutions to be protected and results and data in the process of research and development, the present invention provides a detailed and profound analysis on the technical problems solved by the technical solutions of the present invention, and some creative technical effects are brought about after solving the problems. The method and the system for locating short circuit fault sections of oilfield distribution networks based on load-side line voltage amplitudes of the present invention are significantly different from the traditional locating methods. At present, fault section location of distribution lines mainly relies on feeder terminal units, faults can only be located between adjacent feeder terminal units, and the feeder terminal installation cost is high. The method and the system for locating short circuit fault sections of oilfield distribution networks based on load-side line voltage amplitudes in the present invention only need to adopt existing load side monitoring terminals of oilfield distribution networks to measure line voltage amplitude of load sides, without conducting phase measurement or adding additional monitoring facilities, and can effectively judge types of short circuit faults and locate sections where faults occur, and finally locate the faults between adjacent load-side measuring nodes. The traditional location methods usually use data acquisition and monitoring control systems to receive fault information, and employ matrix algorithm, artificial intelligence algorithm and other algorithms to analyze and process fault location problems, and finally position fault sections. In complex network structures, the calculation is large, and fault location errors are larger in the case of information distortion or information loss. The method and the system for locating short circuit fault sections of oilfield distribution networks based on load-side line voltage amplitudes in the present invention do not need complicated calculation process, Description occupy small computer memory, have fast calculation speed, and achieve high fault tolerance for fault location under the condition of information distortion or information loss. Secondly, taking the technical solutions as a whole or from the perspective of products, it can be seen that technical solutions to be protected in the present invention have following technical effects and advantages: the present invention discloses a method and a system for locating short circuit fault sections of oilfield distribution networks based on load-side line voltage amplitudes, utilizes load-side monitoring devices to obtain line voltage amplitudes to realize the location of fault sections, and locates faults between adjacent load side monitoring devices, and the present invention achieves more accurate locating results and has better stability. The present invention provides a key technology for realizing the rapid location of short circuit faults of medium voltage sides based on load side information, which can further improve the reliability of power supply systems and are conducive to the further development of oilfield distribution networks. Thirdly, auxiliary evidences of inventiveness of claims of the present invention are also embodied as follows: aiming at the problem of limited deep utilization of fusion terminal data in low-voltage platform areas, the present invention judges the operation characteristics of medium-voltage sides of power grids by using line voltage data of low-voltage sides without adding additional equipment, and narrows the locating range to adjacent load side fusion terminals, so as to provide support for oilfield production. Brief Description of the Drawings Accompanying drawings incorporated in, constitute a part of this specification, illustrate embodiments consistent with the disclosure and, together with the description, serve to explain principles of the disclosure. Figure 1 is a flow chart of a method for locating short circuit fault sections of oilfield distribution networks based on load-side line voltage amplitudes provided by an embodiment of the present invention. Figure 2 is a schematic diagram showing a system for locating short circuit fault sections of oilfield distribution networks based on load-side line voltage amplitudes provided by an embodiment of the present invention. Figure 3 is a schematic diagram showing a method for locating short circuit fault sections of oilfield distribution networks based on load-side line voltage amplitudes provided by an embodiment of the present invention. Description Figure 4 is a schematic diagram of terminal data transmission provided by an embodiment of the present invention. Figure 5 is a schematic diagram of cycle wave selection provided by an embodiment of the invention. Figure 6 is a schematic diagram of locating criteria for branchless lines provided by an embodiment of the present invention. Figure 7 is a schematic diagram of branch line location criteria provided by an embodiment of the present invention. Figure 8 is an oilfield distribution network topology diagram provided by an embodiment of the invention Figure 9 is a fault component distribution diagram of main line positive sequence current for fault 1 provided by an embodiment of the present invention. Figure 10 is a fault component distribution diagram of main line positive sequence current for fault 2 provided by an embodiment of the present invention. Figure 11 is a fault component distribution diagram of branch line positive sequence current for fault 2 provided by an embodiment of the present invention. The markups are indicated as follows: 1-fault location startup module; 2-fault type judgment module; 3- section location module for two-phase short circuit faults; and 4-section location module for three-phase short circuit faults. Specific Embodiments In order to make the above purposes, features and advantages of the present invention more obvious and understandable, the specific embodiments of the present invention are described in detail in combination with the attached drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. However, the present invention can be implemented in many other ways different from those described here, and those skilled in the art can make similar improvements without departing from the connotation of the present invention, so the present invention is not limited by the specific implementation disclosed below. 1. Explanation of Embodiments Embodiments of the present invention provides a method for locating short circuit fault sections of oilfield distribution networks based on load-side line voltage amplitudes, comprising using oilfield load-side measuring terminals to measure line voltage amplitudes of load-side measuring nodes in a system before and after a short Description circuit fault, determining type and phase of the short circuit fault based on measured line voltage amplitudes of load-side measuring nodes before and after the short circuit fault; in the case of a two-phase short circuit, combining network topology, line parameters and the measured line voltage amplitudes of load-side measuring nodes to calculate magnitudes of positive sequence current fault components at medium-voltage sides, forming fault section location criteria to determine a short circuit fault section of distribution network based on a distribution law that positive-sequence current fault component amplitudes upstream of a fault point are much greater than those of the downstream of the fault point and branch lines; and in the case of a three phase short circuit, horizontally comparing line voltage amplitudes of different load-side measuring nodes, and forming the fault section location criteria and determining a short circuit fault section of distribution network based on a distribution law that line voltage amplitudes of load-side measuring nodes monotonically decrease from a power source point to a fault point. The present invention only needs to use existing load side monitoring terminals in the oilfields to measure load-side line voltage amplitudes, without conducting phase measurement or adding additional monitoring facilities, and can effectively judge types of short circuit faults and locate sections where faults occur, and finally locate the faults between adjacent load-side measuring nodes. Embodiment 1 As shown in figure 1, the method for locating short circuit fault sections of oilfield distribution networks based on load-side line voltage amplitudes comprising following steps of: S101-on a basis of distribution characteristics of load-side line voltage amplitudes when short circuit faults occur at medium-voltage sides, using line voltage amplitudes of load-side measuring nodes to determine type and phase of a short circuit fault. S102-according to a short circuit fault phase selection result, when a two-phase short circuit is determined, using measured line voltage amplitudes of load-side measuring nodes to calculate magnitudes of positive sequence current fault components at medium-voltage sides; S103-when a two-phase short circuit is determined, determining a fault occurring section and identifying fault location based on distribution characteristics of calculated positive sequence current fault components at medium-voltage sides ; and S104-according to a short circuit fault phase selection result, when a three-phase short circuit is determined, horizontally comparing line voltage amplitude differences of adjacent load-side measuring nodes, determining a fault occurring section and identifying fault location based on distribution Description characteristics of calculated line voltage amplitude differences of adjacent load-side measuring nodes. Embodiment 2 According to the method for locating short circuit fault sections of oilfield distribution networks based on load-side line voltage amplitudes provided by Embodiment 1, a preferable embodiment is provided herein and has following differences from Embodiment 1: in the S101, when load-side monitoring terminal data meets startup criteria, if line voltage amplitudes of three phases at an any load-side measuring node i are equal, a three-phase short circuit fault is judged to occur in a system; a line voltage amplitude of the any load-side measuring node i between phase A and phase B remains constant before and after the short circuit fault, a BC two-phase short circuit fault is judged to occur in the system; and if a line voltage amplitude of the any load-side measuring node i between phase C and phase A remains constant before and after the short circuit fault, an AB two-phase short circuit fault is judged to occur in the system. Embodiment 3 According to the method for locating short circuit fault sections of oilfield distribution networks based on load-side line voltage amplitudes provided in Embodiment 1, a preferable embodiment is provided herein and has following differences from Embodiment 1: in the $102, when a two-phase short circuit fault occurs, the line voltage amplitudes of three phases at the any load-side measuring node i only relate to three phase voltages thereof before a medium-voltage side node fault, Vin Usa and Uev a transformation ratio of transformers n and a voltage generated by a positive sequence current fault component at any load-side measuring node, wherein Vio, Us, and Ut are obtained from a constant line voltage among three line voltage amplitudes at any load-side measuring node i, and the transformation ratio of transformers n is known, thus for the any load-side measuring node, an amplitude and a phase of AU, are calculated by two changing line voltage amplitudes among three line voltage amplitudes thereof, and positive sequence current fault components between sections are obtained by dividing ; AU i ; ; ; subtraction of Uy corresponding to any two adjacent load side measuring nodes into line impedances between the two adjacent load side measuring nodes. Embodiment 4 According to the method for locating short circuit fault sections of oilfield distribution networks based on load-side line voltage amplitudes provided in Description Embodiment 1, a preferable embodiment is provided herein and has following differences from Embodiment 1: in the S103, positive sequence current fault component between a power source point and a fault point is much larger than a positive sequence current fault component downstream of the fault point, if there is no branch line in the system, among all sections which are less than 10% of a positive sequence current fault component at a head end of the branchless line, an upstream section closet to a power source point section is a fault-occurring position, if no section meets conditions and a positive sequence current fault component at a tail end thereof is smaller than positive sequence current fault components at upstream sections thereof, the tail end section thereof is the fault-occurring section; if there are branch lines in the system, locating criteria for branchless lines are applied to the main line to determine a fault-occurring position, if there is no branch line downstream of a faulty section, the fault section is located the fault-occurring section, if there is a branch line downstream of the faulty section, the power source point is taken as a starting point and a tail end node of the branch line is taken as an end point, locating criteria for branchless lines are applied to the branch line to determine a fault-occurring position, if a section is determined to be the same as the main line, the section is located as the fault-occurring section; and if there is still a branch line downstream of the fault-occurring section, the above process is repeated until there is no branch line downstream of located section. Embodiment 5 According to the method for locating short circuit fault sections of oilfield distribution networks based on load-side line voltage amplitudes provided in Embodiment 1, a preferable embodiment is provided herein and has following differences from Embodiment 1: in the S104, when the three-phase short circuit occurs, the load-side line voltage amplitudes decrease monotonically from a power source point to a fault point, based on mentioned distribution law, line voltage amplitudes of load-side measuring nodes are measured, voltage drops caused by loading currents are taken into account, and three-phase short circuit locating criteria are as follows: calculating absolute values of subtraction of line voltage amplitudes at adjacent load-side measuring nodes, locating sections where branch lines first appear to have voltages smaller than a set value, and determining an upstream section farthest from a power point section among located sections to be a fault occurring section. Embodiment 6 As shown in figure 2, an embodiment of the present invention provides a system for locating short circuit fault sections of oilfield distribution networks based on load-side line voltage amplitudes, comprising: a fault location startup module 1 configured to record load-side line voltage amplitudes, and start fault location process when a sudden change of a line voltage is greater than a set value; Description a fault type judgment module 2 configured to judge fault types via line voltage amplitudes before and after faults, and determine fault phases when two-phase short circuit faults occur in the system; a section location module for two-phase short circuit faults 3 configured to calculate positive sequence current fault components at medium-voltage sides via load-side line voltages, and determine sections where the two-phase short circuit faults occur based on distribution characteristics of calculated positive sequence current fault components at medium-voltage sides; and a section location module for three-phase short circuit faults 4 configured to horizontally compare line voltage amplitude differences of adjacent load-side measuring nodes, and determine sections where the three-phase short circuit faults occur based on distribution characteristics of calculated load-side line voltage amplitude differences. Embodiment 7 Another embodiment of the present invention provides a method for locating short circuit fault sections of oilfield distribution networks based on load-side line voltage amplitudes, which realizes following functions by programming and empowering load side monitoring terminals: keeping line voltage data read within one minute, when a fault occurs in the system, using a sudden change in a line voltage as a startup criterion, taking a moment when the line voltage mutation is greater than 0.1U, as a fault moment, and simultaneously reading two cycles of a T after a moment of failure and a 7, before the moment of failure as calculation data of fault phase selection and fault location. Line voltage amplitudes obtained from the load side monitoring terminals are used to judge type of short circuit faults, if line voltage amplitudes of three phases at an any load-side measuring node i are equal, a three-phase short circuit fault is judged to occur in a system; a line voltage amplitude of the any load-side measuring node i between phase A and phase B remains constant before and after a short circuit fault, a BC two-phase short circuit fault is judged to occur in the system; and if a line voltage amplitude of the any load-side measuring node i between phase C and phase A remains constant before and after the short circuit fault, an AB two-phase short circuit fault is judged to occur in the system. When a three-phase short circuit occurs, load side voltage line amplitudes decrease monotonically from a power source point to a fault point, based on mentioned distribution law, line voltage amplitudes of load-side measuring nodes are measured, voltage drops caused by loading currents downstream of the fault point are taken Description into account, and three-phase short circuit locating criteria are as follows: calculating absolute values of subtraction of line voltage amplitudes at adjacent load-side measuring nodes, locating sections where branch lines first appear to have voltages smaller than a set value, and determining an upstream section farthest from a power point section among located sections to be a fault occurring section. Herein, the setting value is taken as 10V under a condition of considering loading size. When a two-phase short circuit occurs in the system, the BC two-phase short circuit is taken as an example, there are following expressions related to the line voltage amplitude of the any load-side measuring node i: lo <0] |B fab n n n n . 3 y y : . [l= PE per n when the two-phase short circuit fault occurs, line voltage amplitudes of three phases at the load-side measuring node i only relate to three phase voltages before a medium-voltage side node fault, Uiso, Ui, and Us, a transformation ratio of i Z, : transformers n, a mutual impedance “ between the node and the fault point, and 1 Fa a fault current *, wherein a voltage of the node during normal operation are obtained from an AB load-side line voltage amplitude, let a voltage of phase A obtained before the fault be a 0 phase, then a three-phase voltage before the fault are obtained according to an A-phase voltage; since the transformation ratio of transformers is known, a product of a mutual impedance Zy and the fault current ; A Z; transformers is known, a product of a mutual impedance “and the fault current Lo 5 vans Baw esti ie Ge dated we AE shauiiie Pe wid “1 is regarded as a variable, which is defined as = 7, therefore, for the load-side measuring node, load-side line voltage amplitudes [tr] and [ti are taken as dependent variables, and an amplitude and a phase of AU, are taken as A PO 25a) independent variables to generate two equations: n and lo || Ean=i43a0,) n I, so as to correspondingly solve two variables, the Description amplitude and the phase of Aly and based on load-side line voltage amplitudes, Aly, Aly ,... and AU, of all load-side measuring nodes in the system are obtained correspondingly; ally corresponding to any two adjacent load side measuring nodes are reduced to 1 Z,-Z be (Ey Geir) which has a phvsical meaning. namelv. a voltage difference 1 Z,—Z be any wns) which has a physical meaning, namely, a voltage difference between the any two adjacent load side measuring nodes when a positive sequence fault current Lan flows into a fault point; when voltage differences between any two adjacent load side measuring nodes mn are defined as A, , voltage differences between sections are Ad, and in combination with line topology and line parameters, positive sequence current fault components between sections are obtained by dividing AU, into line impedances between mn. When there is no branch line in the system, positive sequence current fault components at medium-voltage sides are obtained via load-side line voltage amplitudes, based on a distribution law that positive sequence current fault components upstream of fault points are much larger than those downstream of fault points, two-phase short circuit fault locating criteria for branch lines are as follows: among all sections which are less than 10% of a positive sequence current fault component at a head end of the branchless line, an upstream section closet to a power point section is a fault-occurring section; if no section meets conditions and a positive sequence current fault component at a tail end of the branchless line is smaller than positive sequence current fault components at upstream sections, the tail end section of the branchless line is the fault-occurring section; When there are branch lines in the system, positive sequence current fault components at medium-voltage sides are obtained via load-side line voltage amplitudes, based on a distribution law that positive sequence current fault components upstream of fault points are much larger than those downstream of fault points and branch lines, two-phase short circuit fault locating criteria for branchless lines are as follows: firstly, applying locating criteria for branchless lines to the main line and judging where a fault occurs, if there is no branch line downstream of a faulty section, locating the faulty section as a fault occurring section; if a branch line exists downstream of the faulty section, taking a power source point as a starting point and a tail end node of the branch line as an end point, and applying locating criteria for branchless lines to judge where the fault occurs, if the faulty section is Description judged to be same as the main line, then locating the faulty section as the fault occurring section; and if it is judged that there is still a branch line downstream of the fault occurring section, repeating above process until there is no branch line downstream of a positioned section. Embodiment 8 Further, an embodiment of the present invention provides a method for locating short circuit fault sections of oilfield distribution networks based on load-side line voltage amplitudes, and a locating flow chart thereof is as shown in figure 3, which comprises following steps of: I. Fault location startup criteria Figure 4 shows composition of a system for locating short circuit fault sections of oilfield distribution networks, comprising a master station and load side monitoring terminals. Monitoring terminal data of oilfield load sides is uploaded to the master station; when a short circuit fault occurs at a medium-voltage side, a voltage of the system drops until a line voltage amplitude of a load-side measuring node drops to 90% of a rated voltage, the fault location process is started and simultaneously two cycles at I after a moment of failure and L before the moment of failure are cycles at *! after a moment of failure and “* before the moment of failure are read as calculation data for fault phase selection and fault location, concrete implementation process of which is shown in figure 5. Il. Judgment of short circuit fault types Line voltage amplitudes obtained from load side monitoring terminals are used to judge types of short circuit faults, if line voltage amplitudes of three phases at an any load-side measuring node i are equal, a three-phase short circuit fault is judged to occur in a system; a line voltage amplitude of the any load-side measuring node i between phase A and phase B remains constant before and after the short circuit fault, a BC two-phase short circuit fault is judged to occur in the system; and if a line voltage amplitude of the any load-side measuring node i between phase C and phase A remains constant before and after the short circuit fault, an AB two-phase short circuit fault is judged to occur in the system. I. Positive sequence current fault components at medium-voltage sides in case of two-phase short circuits When a two-phase short circuit occurs in the system, the BC two-phase short circuit is taken as an example, there are following expressions related to the line voltage amplitude of the any load-side measuring node i between phase B and phase C are Description expressed by following equations: [0 P| b n n flo =e] SC Bh) ibe| = = n n le [| EC =) - n n _ wherein when the two-phase short circuit fault occurs, line voltage amplitudes of three phases at the load-side measuring node i only relate to three phase voltages before a medium-voltage side node fault, Vio, Ui, and Uw, a transformation ratio of transformers n, a mutual impedance Zy between the node and the fault point, and Lon a fault current *, wherein a voltage of the node during normal operation are obtained from an AB load-side line voltage amplitude, let a voltage of phase A obtained before the fault be a 0 phase, then a three-phase voltage before the fault are obtained according to an A-phase voltage; since the transformation ratio of transformers is known, a product of a mutual impedance Zy and the fault current ; . Z; transformers is known, a product of a mutual impedance “and the fault current I . BH 1 eesmriien aE 5 vusesiin akibe daria si BOT thaabonm Fa wha ww is regarded as a variable, which is defined as = 7, therefore, for the any load-side measuring node, load-side line voltage amplitudes tl and It.) are taken as dependent variables, and an amplitude and a phase of AU, are taken as A i 0) independent variables to generate two equations: n and lo || En —iat, So iH I, so as to correspondingly solve two variables, the amplitude and the phase of AU, and based on load-side line voltage amplitudes, aU, AU, ,.. and aU, of all load-side measuring nodes in the system are obtained correspondingly; Ay corresponding to any two adjacent load side measuring nodes are reduced to Description I Z,-Z be ay wr) which has a physical meaning, namely, a voltage difference between the two adjacent load side measuring nodes when a positive sequence fault 1 current “7 flows into a fault point: when voltage differences between anv two current Law flows into a fault point; when voltage differences between any two adjacent load side measuring nodes mn are defined as AU, voltage differences between sections are AU, and in combination with line topology and line parameters, positive sequence current fault components between sections are obtained by dividing AU,, into line impedances between mn. Iv. Fault location based on obtained distribution of positive sequence current fault components in case of two-phase short circuits Figure 6 shows a two-phase short circuit fault occurring on a branchless line. Since a voltage of a load-side measuring node n is approximately equal to a voltage of AU, =AU,—-AU, = AU, a fault point f, i.e., AU, =AU, -AU, ~AU,-AU, = AU and let a calculated value of positive sequence current fault component at a section mn be Lo, then AU, AU, Jt — Ym Tr I = — ey - <I following formulas are derived: Lop t lp Lm tls and 1, = I~ 1,~0 Based on the above distribution characteristics, two-phase short circuit locating criteria for a branchless line are as follows: among all sections which are less than 10% of a positive sequence current fault component at a head end of the branchless line, an upstream section closet to a power point section is a fault-occurring section; if no section meets conditions and a positive sequence current fault component at a tail end of the branchless line is smaller than positive sequence current fault components at upstream sections, a tail end section of lines is the fault-occurring section. Figure 7 shows a two-phase short circuit fault occurring on a branch line. According to above fault locating analysis for the branchless line, positive sequence current fault components of sections are obtained via load-side line voltage amplitudes, wherein I~ Lm Lut ml xly = 0 and Ly <1, < Lm, Description based on the distribution characteristics, two-phase short circuit locating criteria for a main line with branch lines are as follows: firstly, applying locating criteria for branchless lines to the main line and judging where a fault occurs, if there is no branch line downstream of a faulty section, locating the faulty section as a fault occurring section; if a branch line exists downstream of the faulty section, taking a power source point as a starting point and a tail end node of the branch line as an end point, and applying the two-phase short circuit locating criteria for branchless lines to judge where the fault occurs, if the faulty section is judged to be same as the main line, then locating the faulty section as the fault occurring section; and if it is judged that there is still a branch line downstream of the fault occurring section, repeating above process until there is no branch line downstream of a positioned section. V. Fault location based on distribution of load-side line voltage amplitudes in case of three-phase short circuits When a three-phase short circuit occurs, load side voltage line amplitudes decrease monotonically from a power source point to a fault point, based on mentioned distribution law, line voltage amplitudes of load-side measuring nodes are measured, voltage drops caused by downstream loading currents of the fault point are taken into account, and three-phase short circuit locating criteria are as follows: calculating absolute values of subtraction of line voltage amplitudes at adjacent load-side measuring nodes, locating sections where branch lines first appear to have voltages smaller than a set value, and determining an upstream section farthest from a power point section among the sections to be a fault occurring section. Herein, the setting value is taken as 10V under a condition of considering load size. In the above-mentioned embodiments, the descriptions of each embodiment have their own emphases, and for parts that are not detailed or recorded in a certain embodiment, refer to the relevant descriptions of other embodiments. The information interaction and execution process between the above-mentioned devices / units are based on the same idea as the method embodiment of the present invention, and its specific functions and technical effects can be found in the method embodiment section, and will not be repeated here. Those skilled in the art can clearly understand that for the convenience and brevity of description, the division of the above-mentioned functional units and modules is only used for illustration. In practical applications, the above function allocation can be completed by different functional units and modules according to needs, that is, the internal structure of the device is divided into different functional units or modules to complete all or part of the functions described above. Each functional unit and module in the embodiment can be integrated into one processing unit, or Description each unit can exist separately physically, or two or more units can be integrated into one unit, and the above-mentioned integrated units can be implemented in the form of hardware or in the form of software functional units. In addition, the specific names of each functional unit and module are only for the convenience of distinguishing each other, and are not used to limit the protection scope of the invention. The specific working process of the units and modules in the above system can refer to the corresponding process in the above-mentioned embodiments, and will not be repeated here. 2. Application examples Application example 1 An application example of the present invention further provides a computer device comprising at least a memory and a processor, wherein the memory stores computer program, when the computer program is executed by the processer, the processor executes the method for locating short circuit fault sections of oilfield distribution networks according to any of the above mentioned. Application example 2 An application example of the present invention further provides a computer-readable storage medium storing a computer program, wherein the processor executes the method for locating short circuit fault sections of oilfield distribution networks according to any of the above mentioned when the computer program is executed by the processor. Application example 3 An application example of the present invention further provides an information data processing terminal, wherein the information data processing terminal is used to implement the steps in the embodiments of the methods mentioned above when it is implemented on an electronic device, and the information data processing terminal is not limited to mobile phone, computer and switch. Application example 4 An application example of the present invention further provides a server, which is used to provide a user input interface to implement the steps in the above method embodiments when implemented on an electronic device. Application example 5 An application example of the present invention further provides a computer program product, when the computer program product runs on an electronic device, the steps in each method embodiment can be realized when the electronic device is executed. Description The integrated units may be stored in a computer readable storage medium if implemented in the form of software functional units and marketed or used as an independent product. Based on such understanding, the present invention realizes all or part of the process in the embodiments of the above mentioned methods, which can be completed by instructing related hardware through a computer program. The computer program can be stored in a computer readable storage medium, and the computer program can realize the steps of the embodiments of the above methods when executed by the processor, wherein, the computer program includes the computer program code, the computer program code can be source code form, object code form, executable file or some intermediate form. The computer readable medium may at least include: any entity or device capable of carrying computer program code to a photographic device / terminal device, a recording medium, a computer memory, a read-only memory (ROM), a random access memory, (RAM), electrical carrier signals, telecommunication signals and software distribution media, for example, a USB flash drive, a removable hard drive, a magnetic disk, or a compact disk. 3. Evidence of Embodiment-Related Effects A 20-node oilfield distribution network simulation model is built in PSCAD as shown in Figure 8, and line parameters and node load parameters are shown in Table 1 and Table 2: Table 1: Line parameters of 20-node oilfield distribution network simulation model Head end Tail end Line impedance Head end Tail end Line impedance node node / Q node node / Q 01 02 0.493+j0.24492 0202 0203 0.372+j0.57148 02 03 0.36+j0.18212 0203 0204 0.164+j0.15072 03 04 0.3811+j0.1884 03 0301 0.4095+j0.4772 04 05 0.819+j0.70336 0301 0302 0.7089+j0.9357 0s 06 0.1872+j0.6154 0302 0303 0.4512+j0.3768 06 07 0.7114+j0.2323 05 0501 0.203+j0.10048 07 08 1.03+j0.73476 0501 0502 0.2842+j0.1444 08 09 1.04+j0.73476 0502 0503 0.372+j0.57148 02 0201 0.3744+j0.1193 0503 0504 0.5075+j0.2574 0201 0202 0.5416+j0.7096 Table 2: node load parameters of 20-node oilfield distribution network simulation model Node No. Node Load / kVA Node No. Node Load / kVA 26+j22 0202 280+j200 5 80+j55 0302 260+ / 185.5 6 80+j55 0303 240+j170 455+j300 0501 240+j170 8 600+j350 0502 100+j62 9 600+j350 0503 100+j62 0201 50+j35 0504 100+j62 When a transition resistance of a short circuit fault is set as 0Q, 2Q and 5Q respectively, analogue simulation is carried out to simulate a fault 1 occurs between nodes 05 and 06, tail end nodes of the line are selected as fault phase selection criteria, in the case of different transition resistances, among line voltage amplitudes obtained by load-side monitoring terminals of tail end nodes of the line, AB line voltage amplitudes remain constant before and after the fault, so the fault type is judged to be a BC two-phase short circuit fault. Positive sequence current fault components at medium-voltage sides under the conditions of different transition resistances are calculated by using the three line voltages of load-side measuring nodes, as shown in Figure 9. When fault currents and two-phase short circuit fault location criteria are applied to positive sequence current fault components of the main line at the medium voltage sides, it can be seen that the fault occurs at nodes 05-06, and there is no branch line downstream of the nodes 05-06, therefore, a result of fault location shows that a BC two-phase short circuit fault occurs between nodes 05-06, which is the same as a set fault type and fault location, and the result of fault location is accurate. When a system load rate is set as 10%, 20%, 50%, 80% and 100% respectively, analogue simulation is carried out to simulate a fault 2 occurs between nodes 0502-0503. Herein, tail end nodes of the line are selected as fault phase selection criteria, under different load rates, among line voltage amplitudes obtained by load-side monitoring terminals of tail end nodes of the line, AB line voltage amplitudes remain constant before and after the fault, so the fault type is judged to be a BC two-phase short circuit fault. Positive sequence current fault components of the main line at medium-voltage sides under different transition resistances are calculated by line voltage amplitudes of three phases at load-side measuring nodes, as shown in Figure 10. When fault currents and two-phase short circuit fault location criteria are applied to positive sequence current fault components of the main line at medium voltage sides, it can be seen that the fault occurs at nodes 04-05, and there is a branch line downstream of nodes 04-05, so locating criteria for branchless lines are applied in a Description manner of taking a head end node of the line as a starting point, and nodes 0504 as an end point. Positive sequence current fault components at the medium-voltage sides are shown in Figure 11. Figure 11 shows that a fault occurring position is located between nodes 0502-0503, and there is no branch line downstream of the 0502-0503 nodes. Therefore, a result of location fault is that a BC two-phase short circuit fault occurs between nodes 0502-0503. The type and location of the fault are the same as that of a set fault, and the result of fault location is accurate. When the system transition resistance is set as 0Q, 2Q and 5Q respectively, analogue simulation is carried out to simulate a fault 3 occurs between nodes 06-07. Herein, tail end nodes of the line are selected as fault phase selection criteria, in the case of different transition resistances, line voltage amplitudes of three phases obtained by load-side monitoring terminals of tail end nodes of the line are equal, so the fault type is judged to be three-phase short circuit fault. Therefore, any line voltage amplitude is selected as fault location data, and absolute values of subtraction of line voltage amplitudes at adjacent load-side measuring nodes under different transition resistances are shown in Table 3. As can be seen from Table 3, sections that first appear in each branch line less than the set value 10V are respectively: 07-08, 02-0201, 03-0301, and 05-0501, wherein a section farthest from a power source point is section 07-08, a position where the short circuit fault occurs is located in an upstream section of the section 07-08, that is, between nodes 06-07, the fault type is a three-phase short circuit fault, which is the same as a set fault type and fault location, and the result of fault location is accurate. Table 3: absolute value of subtraction of line voltage amplitudes at adjacent load-side measuring nodes Number of adjacent Ouof transition 2Qof transition 5Qof transition |load-side measuring resistance resistance resistance nodes 01-02 67 49 35 02-03 47 34 23 03-04 47 33 23 04-05 123 80 50 05-06 R58 22 14 06-07 41 29 21 07-08 0 2 4 Description 08-09 0 2 2 02-0201 0 0 0201-0202 3 3 4 0202-0203 0 0 0203-0204 0 0 0 03-0301 0 0 0301-0302 3 3 0302-0303 2 0 05-0501 0 2 0501-0502 0 0 0 0502-0503 0 0 0 0503-0504 0 0 0 The above mentioned are only the specific embodiments of the present invention, but the protection scope of the present invention is not limited to this, and any modification, equivalent substitution and improvement made by those skilled in the art within the technical scope disclosed by the invention and within the spirit and principles of the invention shall be covered by the scope of protection of the present invention.

Claims

Claims 1. A method for locating short circuit fault sections of oilfield distribution networks based on load-side line voltage amplitudes, comprising the steps of: S1-on a basis of distribution characteristics of load-side line voltage amplitudes when a short circuit fault occur at medium-voltage sides, using line voltage amplitudes of load-side measuring nodes to determine a type and a phase of the short circuit fault; S2-according to a short circuit fault phase selection result, when a two-phase short circuit is determined, using measured line voltage amplitudes of load-side measuring nodes to calculate magnitudes of positive sequence current fault components at medium-voltage sides, determining a fault occurring section and identifying fault location based on distribution characteristics of calculated positive sequence current fault components at medium-voltage sides; and S3-according to the short circuit fault phase selection result, when a three-phase short circuit is determined, comparing line voltage amplitude differences of adjacent load-side measuring nodes, determining a fault occurring section and identifying fault location based on distribution characteristics of calculated line voltage amplitude differences of adjacent load-side measuring nodes.

2. The method for locating short circuit fault sections of oilfield distribution networks based on load-side line voltage amplitudes according to claim 1, wherein in the S1, when load-side monitoring terminal data meets startup criteria, if line voltage amplitudes of three phases at any load-side measuring node i are equal, a three-phase short circuit fault is judged to have occurred in a system; wherein if a line voltage amplitude of the load-side measuring node i between phase A and phase B remains constant before and after the short circuit fault, a BC two-phase short circuit fault is judged to have occured in the system; and if a line voltage amplitude of the any load-side measuring node i between phase C and phase A remains constant before and after the short circuit fault, an AB two-phase short circuit fault is judged to have occured in the system.

3. The method for locating short circuit fault sections of oilfield distribution networks based on load-side line voltage amplitudes according to claim 2, wherein when the BC two-phase short circuit fault occurs, a relationship of the line voltage amplitude of the load-side measuring node i between phase B and phase C are expressed by following equations: Claims 11 n n [0c] =; p25) | C+ 17) ALPE , wherein [he] PEC BZ) n 7 J; f : i represents an any load-side measuring node, Vis, Ul, and Yeo respectively refer to three phase voltages before a medium-voltage side node fault, n represents a transformation ratio of transformers, Zy represents a mutual impedance ! } } Los between the any load-side measuring node and a fault point, and represents between the any load-side measuring node and a fault point, ana“ represents a fault current; a voltage of the any load-side measuring node in normal operation is obtained via an AB load-side line voltage amplitude after fault, let a voltage of phase A before fault be a zero phase, and three phase voltages before fault are obtained according to the voltage of phase A before fault; and the transformation ratio of transformers is known while a product of mutual impedance Zs and the J JAM is regarded as a variable, which is defined as [RS for the load-side measuring node, load-side line voltage amplitudes i " A are taken as dependent variables, and an amplitude and a phase of Ur are taken pf Ea EE) ibe| = as independent variables to generate two equations: n | |= Eas, | and “ n I, so as to correspondingly solve two variables, and n 1, so as to correspondingly solve two variables, ’ AU, __— the amplitude and the phase of ¥: and based on load-side line voltage AU, AU,, amplitudes, AU, AU, and AU, of all load-side measuring nodes in the system are obtained correspondingly; and AU, ~~ ¥ corresponding to any two adjacent load-side measuring nodes are reduced to 1,,(Z, =Zur) mals a crmltama Aiffaranea latiiman ams farm adiarant laad cide ", namely a voltage difference between any two adjacent load-side Claims measuring nodes when a positive sequence fault current flows into a fault point; a voltage difference between two adjacent load-side measuring nodes m and nis defined as AU, and when voltage differences AU, between all sections are obtained, in combination with line topology and line parameters, positive sequence current fault components between all sections are obtained by dividing AU, into line impedances between m and n.

4. The method for locating short circuit fault sections of oilfield distribution networks based on load-side line voltage amplitudes according to claim 1, wherein in the S2 of determining a fault occurring section and identifying fault location based on distribution characteristics of calculated positive sequence current fault components at medium-voltage sides when a two-phase short circuit is determined, a voltage of a load-side measuring node n is equal to a voltage of a fault point f, i.e., AU, =AU, AU, ~AU, -AU, = AU, and let a calculated value of positive sequence current fault component at a section ir mn be Im, then following formulas are derived: AU, AU, jr — “2mm Tm r I =— — gy - <I Lys +Zy Zs +p Le Lo, and 1, =0, based on the distribution characteristics, two-phase short circuit locating criteria for a branchless line are as follows: among all the sections which are less than 10% of a positive sequence current fault component at a head end of the branchless line, and an upstream section closet to a power point section is a fault-occurring section; if no section meets conditions and a positive sequence current fault component at a tail end of the branchless line is smaller than positive sequence current fault components at upstream sections, the tail end section of the branchless line is the fault occurring section; according to above fault locating analysis for the branchless line, positive sequence current fault components of sections are obtained via load-side line PE bowl. Woo od voltage amplitudes, wherein Iy=1, Ly “ly 0 and La<l,< Ln, based on the distribution characteristics, two-phase short circuit locating criteria for a main line with branch lines are as follows: firstly, applying locating criteria for branchless lines to the main line and judging where a fault occurs, if there is no branch line downstream of a faulty section, locating the fault section as the fault occurring section; if a branch line exists downstream of the fault section, taking a power source point as a starting point and a tail end node of the branch Claims line as an end point, applying the two-phase short circuit locating criteria for branchless lines and judging where the fault occurs, if the fault section is judged to be same as the main line, then locating the fault section as the fault occurring section; and if it is judged that there is still a branch line downstream of the fault occurring section, repeating above process until there is no branch line downstream of a positioned section.

5. The method for locating short circuit fault sections of oilfield distribution networks based on load-side line voltage amplitudes according to claim 1, wherein in the S3, when the three-phase short circuit occurs, the load-side line voltage amplitudes decrease monotonically from a power source point to a fault point, based on a distribution law, line voltage amplitudes of load-side measuring nodes are measured, voltage drops caused by loading currents are taking into account, and three-phase short circuit locating criteria are as follows: calculating absolute values of subtraction of line voltage amplitudes at adjacent load-side measuring nodes, locating sections where branch lines first appear to have voltages smaller than a set value, and determining an upstream section farthest from a section of power source point among positioned sections to be the fault occurring section.

6. A system for locating short circuit fault sections of oilfield distribution networks based on the method for locating short circuit fault sections of oilfield distribution networks according to any of claims 1 to 5, comprising: a fault location startup module (1) configured to record load-side line voltage amplitudes, and start fault location process when a sudden change of a line voltage is greater than a set value; a fault type judgment module (2) configured to judge fault types via line voltage amplitudes before and after faults, and determine fault phases when two-phase short circuit faults occur in the system; a section location module for two-phase short circuit faults (3) configured to calculate positive sequence current fault components at medium-voltage sides via load-side line voltages, and determine sections where the two-phase short circuit faults occur based on distribution characteristics of calculated positive sequence current fault components at medium-voltage sides; and a section location module for three-phase short circuit faults (4) configured to horizontally compare line voltage amplitude differences of adjacent load-side measuring nodes, and determine sections where the three-phase short circuit faults occur based on distribution characteristics of calculated load-side line voltage amplitude differences.

7. The system for locating short circuit fault sections of oilfield distribution networks Claims according to claim 6, further comprising a master station and load-side monitoring terminals, wherein the load-side monitoring terminals determine fault type and fault phase data based on monitored characteristics of line voltage amplitudes of load-side measuring nodes before and after a fault, and upload determined fault type and fault phase data to the master station; when a short circuit fault occurs at a medium voltage side, a voltage of the system drops until a line voltage amplitude of a load-side measuring node drops to 90% of a rated voltage, the fault location process is started and simultaneously two cycles at a T, after a moment of failure and a 7, before the moment of failure are read as calculation data for fault phase selection and fault location.

8. A computer device comprising a memory and a processor, wherein the memory stores computer program, when the computer program is executed by the processer, the processor executes the method for locating short circuit fault sections of oilfield distribution networks according to any of claims 1 to 5.

9. A computer-readable storage medium storing a computer program, wherein when the computer program is executed by the processer, the processor executes the method for locating short circuit fault sections of oilfield distribution networks according to any of claims 1 to 5.

10. A feeder line terminal unit for locating short circuit fault sections of oilfield distribution networks, wherein the feeder line terminal unit is configured to implement on an electronic device and provide a user input interface to implement the method for locating short circuit fault sections of oilfield distribution networks according to any of claims 1 to 5.

Citation Information

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