37results about How to "Reduce outage time" patented technology

The invention discloses an intelligent opening and closing method and system for a reclosing circuit breaker based on an electromagnet, and relates to the field of intelligent control, and the method comprises the steps: monitoring a line current in real time, comparing the line current with a preset threshold value, and carrying out the opening after the overcurrent abnormality is detected. Entering a first time delay stage after opening, comprehensively evaluating the states of the circuit breaker and the circuit, and constructing a dynamic weight index system to calculate an evaluation score; if the score exceeds a threshold value, closing is carried out after time delay is finished, otherwise, an alarm is triggered. And entering a second delay stage after switching on, continuously monitoring the electric parameters and establishing an anomaly judgment mechanism, forming a closed-loop protection process of monitoring, switching off, evaluating, switching on and re-monitoring, and realizing intelligent linkage of overcurrent protection and state self-adaption. The method has the advantages that through real-time line electric parameter monitoring, multi-dimensional state evaluation and an intelligent decision-making mechanism, precise opening and closing of the circuit breaker are achieved, the power supply reliability is improved, the power failure time is shortened, and the misoperation risk is reduced.

The invention provides an evaluation and repair method and system for a composite bushing umbrella skirt. The method comprises the following steps: detecting and evaluating the current aging state of the composite bushing umbrella skirt to obtain an aging grade; setting a repair decision according to the aging level; and repairing the composite sleeve umbrella skirt according to the result of the repairing decision. Through the processing of the steps, the evaluation and restoration method breaks through the limitation of detection decentralization, evaluation subjectivity and restoration manual operation in the prior art, establishes a standardized grading evaluation and decision-making mechanism, constructs a whole-process automatic restoration system, and improves the accuracy of the whole-process automatic restoration. According to the method, the aging state of the composite sleeve umbrella skirt can be automatically and accurately evaluated, the repairing process is intelligently and adaptively executed, the repairing effect is verified in a closed loop mode, and standardization, automation and precision of aging repairing of the composite sleeve umbrella skirt are achieved, so that the operation and maintenance cost and dependence on manpower are greatly reduced on the premise that the repairing quality is guaranteed, and the repairing efficiency is improved. And the repair efficiency and quality of the composite sleeve umbrella skirt are improved.

This utility model discloses a dedicated drawer switch and switch cabinet developed based on a pull-out low-voltage switchgear, belonging to the field of power supply equipment. The drawer switch includes a drawer body, an input socket, a switch assembly, and a locking assembly. The input socket is located on the drawer panel and electrically connected to a disconnecting switch. The switch assembly includes an operating handle and a drive rod. The operating handle is rotatably mounted on the drawer panel and can rotate between an open and closed position. The operating handle drives the disconnecting switch via the drive rod. The locking assembly includes a connecting structure and a locking pin. A fixing hole is provided in the drawer compartment corresponding to the locking pin. The locking pin is connected to the drive rod via the connecting structure. When the operating handle is in the open position, the locking pin disengages from the fixing hole; when the operating handle is in the closed position, the locking pin is inserted into the fixing hole. The switch cabinet includes a drawer compartment, and the drawer compartment is equipped with the aforementioned drawer switch.

A cable channel environment automatic adjusting device disclosed by the present invention comprises a monitoring module, a communication module, a CPU processor, a power supply module and a control module, an output end of the monitoring module is connected with the CPU processor, a power supply port of the CPU processor is connected with the power supply module, the CPU processor is further electrically connected with the communication module and the control module, and the communication module is wirelessly connected to a mobile equipment terminal. The monitoring module collects water level, temperature, humidity and video environment information of accumulated water of the cable channel and transmits the environment information to the CPU processor, and the control module is started through the CPU processor to automatically adjust the environment of the cable channel. The cable can reliably operate in a normal-temperature and dry environment, the service life of the cable is effectively prolonged, the power failure time is shortened, and the power supply reliability is improved.

The application relates to the technical field of power distribution control, in particular to an active power distribution network fault self-healing system and a method thereof, which comprises a data sensing module, a fault positioning module, an isolation control module, a fault self-healing module and a power supply recovery module, and realizes intelligent processing of the whole process from fault detection to power supply recovery through cooperation of the multiple modules. The system can quickly position faults based on FTU layout structure and operation data, optimizes analysis efficiency in combination with a GPU computing power dynamic distribution mechanism, and realizes accurate isolation of a fault area, self-healing repair and smooth grid recovery by using intelligent strategy generation and digital twin technology. The application effectively improves the power supply reliability, system stability and operation intelligent level of the power distribution network.

The application discloses a kind of network unmanned aerial vehicle inspection achievement automatic back transmission and defect identification method, it is related to power distribution network inspection technical field.The purpose is to solve the problems of low efficiency, fault response lag, data transmission without security and defect identification relying on artificial in traditional manual inspection.The method comprises: unmanned vehicle carries unmanned aerial vehicle and hangar drives to parking point, unmanned aerial vehicle takes off and carries out inspection and collects achievement data;After unmanned aerial vehicle returns, unmanned aerial vehicle platform processes and transmits achievement data to unmanned aerial vehicle management platform;Management platform uses AI image recognition technology to identify defects in data, generates identification results;Finally, management platform synchronizes identification results to power grid digital brain platform, and is associated with equipment operating state storage.The application realizes the full-process automation and intelligentization of distribution network inspection, greatly improves the inspection efficiency and the accuracy of data processing, optimizes the fault response mechanism, and provides strong support for the intelligent operation and maintenance of distribution network line.

The application discloses a kind of electric power facilities flood disaster space heterogeneity analysis method and system, the method includes receiving to strong rainfall defense alarm, disaster early warning after flood disaster emergency response notice, start the process of electric power facilities flood disaster space heterogeneity analysis;According to the water level sensing monitoring information of the disaster power facility ontology obtained by processing, the individual area of the disaster power facility region and the total area of the disaster power facility region, construct the neural network of the damaged range of the disaster power facility region, and output the monitoring analysis result of the spatial heterogeneity of the disaster power facility region, i.e.The method and system of the application solve the spatial distribution index of the disaster power facility region, draw monitoring water level spatial distribution curve, crack the problem of describing flood disaster space heterogeneity, help electric power enterprise to guide to carry out emergency early warning, load transfer, flood control reinforcement, repair power, material allocation, and greatly reduce power equipment downtime and customer outage time.

This invention relates to the field of power metering technology, specifically disclosing a phase sequence switching control method for energy meters that ensures the safety of the secondary circuit of a current transformer (CT) / potential transformer (PT). The method synchronously acquires and converts three-phase voltage and current signals, constructs a multi-dimensional spatial vector of phase angles, calculates the spatial angle between the vector and the positive-sequence reference vector, and combines this with phase dispersion to generate accurate phase sequence status values ​​to determine reverse phase sequence. When reverse phase sequence is determined, a phased safety switching command sequence is generated based on real-time electrical status verification: first, a disconnect command is issued after verifying voltage stability; then, a current short-circuit command is issued only after verifying a valid voltage drop. The action units are sequentially driven to perform voltage disconnection and current short-circuit operations, driving the dual-contact unit to synchronously switch the three-phase wiring. After switching, the circuit is restored and the phase sequence is re-verified. If multiple failures occur, an adjustment and safety locking mechanism is activated. This invention solves the problems of open circuit on the CT secondary side and short circuit on the PT secondary side during switching.

This utility model relates to a surge arrester that is easy to disassemble, comprising several surge arrester units, with adjacent surge arrester units detachably connected via a threaded structure. Each surge arrester unit includes: a connecting cylinder with a silicone rubber shed on its outer side; a nonlinear resistor element detachably installed inside the connecting cylinder; the uppermost and lowermost surge arrester units are respectively detachably connected to an upper connecting seat and a lower connecting seat; a mating part is integrally formed at the lower end of the connecting cylinder, and the mating part has external threads on its outer side; the inner walls of adjacent connecting cylinders have internal threads adapted to the external threads, achieving detachable connection through thread engagement. This easily disassembled surge arrester, due to its detachable structural design, allows for replacement of only the damaged component or the corresponding surge arrester unit when components such as the silicone rubber shed or the nonlinear resistor element are damaged, without replacing the entire surge arrester, significantly reducing maintenance costs and material waste.

This invention discloses a multifunctional cable grounding box, including a grounding box body, a grounding bar inside the box, a control switch below the grounding bar, and a protector between the grounding bar and the control switch. The protector includes a primary protector and a backup protector arranged in parallel. One end of each protector is connected to the grounding bar, and the other end is connected to the control switch, allowing switching between the primary and backup protectors via the control switch. An insulation transition section is correspondingly located below the control switch, and a current-guiding plate is connected to the insulation transition section, which is connected to the core wire clamp via the current-guiding plate. This design enables rapid switching of the protectors, balancing power supply continuity, circuit safety, and maintenance convenience. Moving the position of the insulation switching bar allows for switching of the grounding mode, flexibly adapting to complex scenarios and achieving full-scene coverage.

The application discloses a kind of monitoring method and device based on ring network cabinet full life cycle twinborn data, it is related to equipment management technical field.The method includes: in production stage, key manufacturing data is collected for ring network cabinet to form production gene bank, combined with unique digital identification to build digital twin initial model, while real-time acquisition various operating data, then rely on manufacturing execution system to individualize correction to initial model, match physical entity parameter, use five-layer collaborative fusion algorithm to deeply fuse production and operating data, diagnose early abnormality and typical fault, carry out ring network cabinet intelligent monitoring and operation and maintenance.The present application can establish complete digital archives for each equipment, realize the whole link data through from production to process optimization, improve early fault identification sensitivity, reduce the repeated incidence of similar fault.

The invention discloses a TDR and passive transient analysis fused power transmission cable fault diagnosis system, and belongs to the technical field of power system fault diagnosis and intelligent diagnosis. The method comprises the following steps: firstly, constructing a pulse injection and signal acquisition integrated device at the end part of a cable, acquiring three-phase voltage and current transient signals, and forming increments before and after a fault; and further constructing an incident wave and a reflected wave at a port, extracting a high-frequency detail component by adopting wavelet decomposition, enhancing wave head features in combination with a TEO energy operator, and analyzing a fault type. And judging a grounding fault, a high-resistance fault or a low-resistance fault. If the fault is a low-resistance fault, passive distance measurement is adopted, and if the fault is a high-resistance fault, the active distance measurement device generates pulse distance measurement. According to the high-resistance and low-resistance self-adaptive distance measurement method, the wave head detectability and the distance measurement stability can be improved under the conditions of different fault impedances and different fault types, and the reliability of cable fault positioning is improved.

This invention discloses a method, apparatus, device, and storage medium for detecting grounding faults in low-voltage lines. Multiple Rogowski coils are spaced apart on the grounding wire of the low-voltage line. These coils are used for non-contact detection of the AC current on the grounding wire. The AC current detected by each Rogowski coil at the same acquisition time is converted from analog to digital and integrated to obtain a voltage data sequence. A filtering algorithm is used to filter the voltage data sequence to obtain an effective leakage current data sequence. Characteristic information representing leakage faults is extracted from the leakage current data sequence. Based on this characteristic information, the location of the grounding leakage fault in the low-voltage line is determined, and the fault location is sent to the mobile terminal of maintenance personnel. This invention achieves the judgment of grounding faults in low-voltage lines through non-contact detection of abnormal currents, reducing labor costs, improving detection efficiency and accuracy, reducing power outage time caused by leakage, and reducing economic losses.

The application discloses a kind of installation structures of strain tower lightning arrester suitable for coastal multi-thunder typhoon area, solve the problem that traditional lightning arrester installation cannot meet the protection demand of strong thunder area and the problem of insufficient wind load resistance and overturning resistance capability.Therein, the lightning arrester includes a lightning arrester body and a fixed base, the lightning arrester body is fixed on the tower body support of strain tower through the fixed base, and is spaced apart from the strain insulator at a set distance;The fixed base is provided with a lightning arrester position adjusting structure for adjusting the installation position of the lightning arrester;The lightning arrester is reinforced by a double-insulator cable-stayed support assembly, the double-insulator cable-stayed support assembly includes two cable-stayed insulators, the oblique downward end of the cable-stayed insulator is connected with the lightning arrester, and the oblique upward end is connected with the tower body support of strain tower.

This invention discloses a current protection method and system for distributed power generation distribution networks, relating to the field of distribution network technology. The invention first collects parameters of the distribution network's common coupling point in real time to predict grid-connected or islanded operation modes. It then distinguishes between inverter-type and synchronous generator-type power supplies based on harmonic content and current response speed, accurately calculating the main protection settings for each power supply. Next, it employs dual-start components for current surges and voltage dips to detect faults, comprehensively determining whether the fault is within or outside the designated area. Subsequently, it determines the braking level based on fault characteristics, dynamically adjusts power supply output limits, and forms a three-dimensional protection system with dual backup protection. Finally, it sets differentiated reclosing delay times based on fault levels and adopts corresponding closing sequences according to the operating mode. This achieves full-scenario adaptability of the protection strategy, significantly improves the accuracy of fault determination, ensures grid stability through the synergy of protection and braking, optimizes recovery strategies to improve power supply reliability, and perfectly adapts to the safe and efficient operation requirements of diverse distribution networks.

The utility model discloses a modularization easy maintenance electric energy meter belongs to the electric energy meter technical field, the electric energy meter comprises a support seat, a metering module, a communication module, a display module and a connecting assembly, one side of the support seat is hinged with a protective cover, one side of the support seat is fixedly provided with a connecting seat, the top end of the connecting seat is provided with a plurality of installing grooves, and the installing grooves are connected with the connecting seat. The metering module, the communication module and the display module are slidably mounted in the corresponding mounting grooves, and the connecting assembly is composed of first connecting parts arranged at the bottom ends of the inner walls of the mounting grooves and second connecting parts arranged at the bottom ends of the metering module, the communication module and the display module. And the first connecting part and the second connecting part are inserted and electrically connected. The electric energy meter is convenient to maintain and flexible in function.

The invention discloses a power distribution network pre-disaster investment scheme optimization system and method based on a genetic algorithm, and the method comprises the steps: building a two-stage optimization model containing pre-disaster investment and post-disaster recovery after obtaining basic data; the expected value of post-disaster load recovery can be maximized under the conditions of budget constraint, node capacity, load recovery, network connectivity and the like. A disaster scene is independently modeled according to representative intensity and spatial distribution, a pre-disaster investment scheme is coded through a genetic algorithm, the fitness is evaluated based on a multi-scene expected recovery load, global optimization is achieved through selection, intersection and variation, and a distributed power supply deployment, line reinforcement and controllable switch configuration scheme meeting budget is output. And rapid recovery is realized in cooperation with post-disaster fault isolation and network reconstruction. The load recovery level and the resource utilization efficiency of the power distribution network after disasters are remarkably improved under limited resources, economy and reliability are considered, and the method can be used for disaster-resistant planning and transformation of the power distribution network.

The invention relates to the technical field of power equipment fault positioning, in particular to a power equipment fault positioning method based on a graph neural network, which comprises the following steps of: establishing a Chain-GNN model to be matched with hardware deployment to pre-process data during normal operation of a circuit, and determining normal operation baseline data; step 2, setting an abnormal score threshold and a bidirectional traveling wave fault rule base, and oppositely and synchronously injecting bidirectional traveling waves into a preliminarily alarmed line, and step 4, after a fault point is confirmed, ensuring normal operation of other equipment; after the sublines are erected, first-aid repair is carried out, and after first-aid repair is completed, all the sublines are disconnected, and original circuit connection is recovered; comparing the normal operation baseline data in the step 1 to determine whether the line recovers normal operation, if so, entering a step 6, and if not, returning to the step 3 to re-determine the fault point; and the Chain-GNN model can automatically archive the whole process data of the fault processing at this time.

The application provides a power transmission line distributed fault diagnosis device, which comprises an upper shell and a lower shell which are detachably connected to enclose a containing cavity, opposite ends of the containing cavity are respectively penetrated by semicircular holes which are communicated with the containing cavity, and two semicircular holes at the same end enclose an installation hole; two groups of wire clamping assemblies are respectively arranged in the installation holes at the two ends; a mainboard is arranged in the containing cavity; a power frequency traveling wave hidden danger sensor is in communication connection with an input end of the mainboard; a positioning module is in communication connection with an input end of the mainboard and is used for monitoring time and position information; a communication module is in communication connection with the mainboard and is used for being in communication connection with a monitoring master station; a battery is in electrical connection with the mainboard, the power frequency traveling wave hidden danger sensor and the positioning module; a solar panel is fixedly connected with an outer wall of the upper shell or the lower shell; a power board is in electrical connection with the solar panel, the mainboard, the power frequency traveling wave hidden danger sensor, the positioning module and the battery; and a transparent protective cover covers the solar panel. The application has the advantages of wide monitoring range, fast response speed and high positioning accuracy.

The application relates to the field of power system automation, and specifically discloses a micro-grid hierarchical rolling collaborative optimization scheduling method under an extreme weather environment on a plateau. The method realizes accurate perception and prediction of weather mutations by constructing a multi-source weather monitoring network and an attention mechanism neural network system; realizes global optimization and local response collaboration by adopting a hierarchical scheduling architecture at the system level, the micro-grid level and the device level; establishes a multi-objective optimization function considering economic, reliable and resilient targets, and introduces robust constraints such as a plateau attenuation coefficient and temperature compensation; uses an improved multi-agent deep deterministic policy gradient algorithm for rolling solution, and triggers an emergency mechanism when a mutation is identified; and realizes model adaptive iteration based on operation data through federated learning. The application can significantly improve the accuracy of weather mutation identification and the real-time performance of scheduling, enhance the resilience and power supply guarantee rate of the micro-grid on the plateau, and ensure the safe operation of key loads under extreme environments.

This invention relates to a stress monitoring and early warning system for suspension clamps in high-voltage power lines, belonging to the field of intelligent monitoring of high-voltage lines. The system consists of RFID sensing tags installed on the suspension clamps and an inspection RFID reader. The RFID sensing tag integrates a force-sensitive overload memory unit, a tag chip, and an antenna. Magnetostrictive alloy microwires within the unit are connected to the force transmission path. When the tensile force exceeds a threshold, an irreversible martensitic phase transformation occurs, resulting in a permanent step decrease in magnetic permeability. The tag chip detects this change via a magnetic sensing circuit, hardware-locking and rewriting the overload flag in the non-volatile storage area. The reader reads the flag non-contactly to determine the overload history and calculates the real-time tensile force through the antenna resonant frequency deviation. The reader can be equipped with a drone or handheld terminal to automatically record overload information and generate work orders. The backend server integrates the data to achieve lifespan prediction and batch replacement planning. This system is passive, maintenance-free, and tamper-proof, combining overload memory and stress detection to improve the safety and intelligence level of line operation and maintenance.

The utility model discloses a low pressure plant change system safety interlocking device relates to electric power automation technical field, including: circuit breaker locking module is set up on 6kV high voltage side circuit breaker and 400V low voltage side circuit breaker, cabinet door locking module is set up on transformer high / low voltage side cabinet door and temporary earthing point box, key exchange box is connected with circuit breaker locking module and cabinet door locking module, the utility model discloses a mechanical interlocking slider has realized " power off - take key - open door - ground " the irreversible flow, and through two exchange three key exchange box, the multi - step operation is simplified as single - action, thereby not only can shorten the power - off time, can also eliminate the possibility of human skipping security step from the physical level.

This utility model provides a tension sensor device for monitoring equivalent icing on transmission lines, comprising: a tension detection body, wherein a tension detector is disposed within the tension detection body; a fixing component, one end of which is connected to the tension detection body and the other end of which is connected to the transmission line tower; and a gripping component, which is disposed on the tension detection body and can grip and fix an insulator on the transmission line. When the gripping component grips and fixes the insulator, the tension detector detects the force on the gripping component, i.e., the force on the transmission line, in real time. This utility model makes the installation and use of the tension sensor device more convenient.

The application discloses a pole-mounted switch with a telescopic ladder structure and integrally-mountable structure, and relates to the technical field of pole-mounted switches. The pole-mounted switch is designed to solve the technical problems of complicated assembly, long installation time and inability to maintain on the electric pole in the prior art. The pole-mounted switch comprises a switch assembly and a fixed ladder vertical support rod. The switch assembly comprises a shell main part, a left side plate fixedly connected to the left end of the shell main part, a right side plate fixedly connected to the right end of the shell main part, a bottom plate installed at the lower end of the shell main part, the left side plate and the right side plate, an upper cross arm inserted into the left end of the shell main part, positioning plates sleeved to the front and rear ends of the upper cross arm, and a lower cross arm clamped and connected to the lower end of the positioning plates. The pole-mounted switch can be assembled on the ground first, and is integrally mounted without the guidance of professional personnel, and is simple to install. The pole-mounted switch is hoisted through a hand crank and a first steel wire rope, and is connected to the electric pole through an upper U-shaped hoop and a lower U-shaped hoop. The pole-mounted switch is convenient to install, disassemble and maintain.

The invention relates to the technical field of electric power measurement, and particularly discloses an electric energy meter phase sequence switching control method for ensuring the safety of a CT / PT secondary circuit, which comprises the following steps of: synchronously acquiring and converting three-phase voltage and current signals, constructing a multi-dimensional space vector of a phase angle, calculating a space included angle between the multi-dimensional space vector and a positive sequence reference vector, and combining phase dispersion to obtain the phase sequence switching control of the CT / PT secondary circuit. An accurate phase sequence state value is generated to judge an inverse phase sequence; when the phase sequence is judged to be the reverse phase sequence, a staged safety switching instruction sequence is generated based on real-time electrical state verification: a disconnection instruction is sent out after the voltage is verified to be stable, a current short-circuit instruction is sent out after the voltage is verified to be effectively reduced, and an action unit is driven in sequence to execute voltage disconnection and current short-circuit operation; the double-contact unit is driven to synchronously switch three-phase wires; after switching is completed, the loop is recovered, and the phase sequence is verified again; if multiple failures occur, a mechanism based on adjustment and safety locking is started; the problems of open circuit of the secondary side of the CT and short circuit of the secondary side of the PT in the switching process are solved.

This utility model discloses a PLC-based low-voltage dual-incoming-line bus tie short-time parallel operation control device, relating to the field of industrial automation control. It includes a first incoming line circuit breaker (1QF), a second incoming line circuit breaker (2QF), and a bus tie circuit breaker (3QF). Synchronous relays are installed in the bus tie cabinet. A PLC controller is also installed in the bus tie cabinet, with its signal input terminal electrically connected to the synchronous relays and voltage monitoring relays installed on the two incoming power supply sides. This PLC-based low-voltage dual-incoming-line bus tie short-time parallel operation control device, through a PLC controller, synchronous relays, voltage monitoring relays, a changeover switch, and operation buttons, connects the signal input terminal of the PLC controller to the synchronous relays and voltage monitoring relays, and connects the control output terminal to the electrical operation circuit of each circuit breaker. Simultaneously, a three-in-one electrical interlocking program and a backup automatic transfer logic program are pre-stored in the PLC controller's memory, constructing a highly integrated and logically rigorous intelligent control system.

The utility model discloses a circuit breaker with split type light weight upper support belongs to circuit breaker technical field, include: circuit breaker body, arc block and sliding block, one side of circuit breaker body is provided with mounting panel, and the upper support and lower support are fixedly arranged on the mounting panel, the arc block is fixedly arranged on the upper support, and the upper portion of circuit breaker body is connected with the arc block and the upper support, the sliding block is slidably arranged in the lower portion of circuit breaker body, and circuit breaker body is mutually clamped with the lower support through the sliding block. Through the setting of arc block and fixed block, make circuit breaker body can be installed on the upper support and lower support quickly, because of the simplification of installation step, the installation time also reduces accordingly. This is particularly important for the power system that needs to be quickly deployed and put into operation, can shorten the power-off time, improve the power supply reliability.

The utility model discloses a quick disassembly and assembly type vacuum contactor, including device body, be equipped with arc extinguishing cover, vacuum arc chamber and support frame in device body, be equipped with the base to support frame lower portion and open the clamping slot in support frame, be equipped with the clamping block on the base, open the insertion slot in the clamping block, the insertion slot is inserted with the insertion rod, be equipped with the screw hole in the insertion rod, be equipped with the bolt in the screw hole, the nut is screwed below the bolt, be equipped with the mounting bracket below the base, open the mounting groove in the mounting bracket, be equipped with the lead screw in the mounting groove, the nut ring is screwed on the lead screw and the nut ring is connected with the base, the motor is connected to the one end of lead screw, can shorten the installation and dismounting time greatly, has improved equipment maintenance and the work efficiency of replacement, has reduced the power failure time, also can accurate adjustment vacuum contactor's horizontal position according to actual electrical layout, equipment spacing demand etc., has improved the flexibility and adaptability of equipment installation.

The embodiment of the application provides a low-voltage cable fault positioning method, a fault positioning instrument, equipment and a medium, and belongs to the cable detection field.The method comprises the following steps: arranging a plurality of sensors along a measured low-voltage cable, synchronously collecting electromagnetic wave signals radiated when a cable fault occurs; performing time-sharing gating and filtering processing to obtain a fault signal; performing analog-digital conversion on the fault signal to extract fault waveform data; extracting a fractal feature vector of the fault waveform data based on a fractal theory; inputting the fractal feature vector into a pre-trained fault classification model, performing nonlinear mapping and classification decision by using a radial basis function, and then outputting a fault type; calculating position information of a fault point according to a time difference of the fault signals received by the sensors; and outputting the fault type and the position information of the fault point.The full-process automation from fault signal collection, type diagnosis to accurate positioning is realized, the power-off time is shortened, and the reliability of urban power supply and the user power consumption satisfaction are ensured.

The invention is suitable for the technical field of relay protection of a power system, and provides a reclosing method, which comprises the following steps that: when a fault of a first phase line is detected, a reclosing device executes a first reclosing action to drive a circuit breaker of the first phase line to be closed; after the circuit breaker of the first phase line is switched on, the reclosing device prohibits discharging within a first preset time; in the first preset time, if it is detected that the second phase line breaks down, the reclosing device executes a second reclosing action, and a circuit breaker of the second phase line is driven to be closed; wherein the first phase line and the second phase line are lines of different phases. According to the reclosing method provided by the embodiment of the invention, secondary reclosing can be completed without waiting for re-charging of the reclosing device, the power failure time of a different-phase fault is remarkably shortened, and the power supply stability is improved.