1. A low-voltage transformer area fault accurate positioning system is applied to a low-voltage transformer area and is characterized by comprising a low-voltage line state monitoring terminal (1), an intelligent power distribution terminal (2) and an intelligent interaction system (3);

the low-voltage line state monitoring terminal (1) is positioned at each branch node of the low-voltage transformer area, and is used for measuring and freezing electric parameter data of each branch node in real time, judging fault conditions in real time and generating a characteristic state sequence signal for identifying a branch line topological structure of the low-voltage transformer area;

the intelligent power distribution terminal (2) is in communication connection with the low-voltage line state monitoring terminal (1), receives the fault working condition and the characteristic state sequence signal in the low-voltage line state monitoring terminal, and accurately positions faults for a low-voltage transformer area according to the fault working condition and the characteristic state sequence signal;

the intelligent interaction system (3) is in communication connection with the low-voltage line state monitoring terminal (1), and is used for inputting equipment account information of the power equipment in the low-voltage station area branch line, generating an XML document and synchronously transmitting the XML document to the low-voltage line state monitoring terminal for storage so as to realize data interaction with a target object.

2. The system for accurately positioning the faults of the low-voltage transformer area according to claim 1, wherein the low-voltage line state monitoring terminal (1) comprises a multi-loop low-voltage monitoring terminal (101), a single-loop low-voltage monitoring terminal (102) and a characteristic signal source (103);

the multi-loop low-voltage monitoring terminal (101) is arranged on each branch box circuit of the low-voltage distribution room, the single-loop low-voltage monitoring terminal (102) is arranged on each single-family meter box circuit of the low-voltage distribution room, and the characteristic signal source (103) is arranged at the connection position of each single-family meter box circuit of the low-voltage distribution room and the branch meter box circuit.

3. The system for accurately positioning the faults of the low-voltage transformer area according to claim 2, wherein in the low-voltage line state monitoring terminal (1):

the multi-loop low-voltage monitoring terminal (101) is used for measuring the electrical parameter data of the three-phase alternating current at the joint of the branch box and the branch switch in real time, and summarizing, metering and storing all the electrical parameter data within a preset time length according to the preset time length; the branch box circuit fault judgment device is used for judging working condition faults of the branch box circuit according to all the electrical parameters within a preset time length;

the single-loop low-voltage monitoring terminal (102) is used for measuring the electric parameter data of the three-phase alternating current at the front end of the inlet switch of the single household meter box in real time, and summarizing, metering and storing all the electric parameter data within a preset time according to the preset time; and the single-family meter box circuit is subjected to working condition fault judgment according to all the electric parameters within preset time.

4. The system for accurately positioning the faults of the low-voltage transformer area according to claim 3, wherein the single-family meter box circuit is connected with an A-phase sampling circuit in three-phase alternating current at the connection position of a branch meter box circuit and is connected with the characteristic signal source (103) in a sampling manner;

the characteristic signal source (103) is connected with the multi-loop low-voltage monitoring terminal (101) in a sampling manner;

the low-voltage line state monitoring terminal (1) measures the electrical parameter data of each branch node in real time, measures the freezing and judges the fault condition in real time, and simultaneously generates a characteristic state sequence signal for identifying the topological structure of the branch line of the low-voltage transformer area, and comprises the following steps:

the multi-loop low-voltage monitoring terminals (101) on the lines of the branch boxes respectively perform mutually independent capacitance switching operation and generate mutually exclusive topology module control signals;

the characteristic signal source (103) receives a topology module control signal of the multi-loop low-voltage monitoring terminal (101) on the same branch box line, and collects the A-phase alternating current signal according to the topology module control signal to generate a characteristic state sequence signal.

5. The system for accurately positioning the faults of the low-voltage transformer area according to claim 4, wherein monitoring end points (4) are arranged on the multi-loop low-voltage monitoring terminal (101) and the single-loop low-voltage monitoring terminal (102), and the monitoring end points (4) are respectively connected with the characteristic signal source (103) and the intelligent power distribution terminal (2) in a sampling manner;

the intelligent power distribution terminal (2) is used for respectively and independently controlling each multi-loop low-voltage monitoring terminal (101) to carry out mutually independent capacitance switching operation so as to generate a characteristic state sequence signal together with a characteristic signal source;

the intelligent power distribution terminal (2) is used for sampling characteristic state sequence signals of all monitoring endpoints (4), and constructing a topology module of the monitoring endpoint (4) where the existing characteristic state sequence signals with the same sequence are located and the characteristic signal source (103) which generates the characteristic state sequence signals;

the intelligent power distribution terminal (2) is used for sequentially fusing the same monitoring end points (4) of all the topology modules to generate a low-voltage distribution area branch line topology structure.

6. The system for accurately positioning the fault of the low-voltage transformer substation according to claim 5, wherein the intelligent power distribution terminal (2) performs accurate positioning of the fault according to the fault working condition and a topology structure of a branch line of the low-voltage transformer substation, and comprises:

and pushing the fault working condition to the position of the corresponding multi-loop low-voltage monitoring terminal (101) or single-loop low-voltage monitoring terminal (102) in the topological structure of the branch line of the low-voltage transformer area, and highlighting the position.

7. The system for accurately locating the fault in the low-voltage transformer area according to claim 6, wherein the communication connection comprises: adopting a dual-mode communication module for communication connection;

the dual-mode communication module comprises an HPLC carrier communication unit and a wireless communication unit.

8. The system for accurately positioning the fault of the low-voltage transformer area according to claim 7, wherein the multi-loop low-voltage monitoring terminal (101) comprises a super energy storage capacitor, and the super energy storage capacitor is used for providing uninterrupted power supply for the multi-loop low-voltage monitoring terminal (101) when the external power supply of the multi-loop low-voltage monitoring terminal (101) is lost.

9. The system for accurately positioning the faults of the low-voltage transformer area according to claim 8,

the intelligent interaction system (3) is used for inputting and converting equipment account information data into an XML document in a mode of scanning two-dimensional codes of the power equipment or manually inputting by utilizing a special portal operated on the intelligent interaction system (3);

the intelligent interaction system (3) is used for transmitting the XML document to a multi-loop low-voltage monitoring terminal (101) which is in the same topological module with the power equipment for storage;

the intelligent power distribution terminal (2) is used for reading XML documents in the multi-loop low-voltage monitoring terminal (101) and pushing the XML documents to the position, corresponding to the multi-loop low-voltage monitoring terminal (101) or the single-loop low-voltage monitoring terminal (102), in the low-voltage distribution area branch line topological structure to display for target object query.

10. A method for accurately positioning a low-voltage transformer area fault, which is implemented based on the system for accurately positioning a low-voltage transformer area fault according to any one of claims 1 to 9, and comprises the following steps:

step S1, installing the low-voltage line state monitoring terminals at each branch node of the low-voltage transformer area, inputting the equipment account information of the power equipment in the branch line of the low-voltage transformer area by using the intelligent interaction system, generating an XML document and synchronously transmitting the XML document to the low-voltage line state monitoring terminals for storage;

step S2, the low-voltage line state monitoring terminal measures the electrical parameter data of each branch node in real time, measures the freezing and judges the fault condition in real time, and generates a characteristic state sequence signal for identifying the topological structure of the branch line of the low-voltage transformer area;

step S3, the intelligent power distribution terminal receives the fault working condition and the characteristic state sequence signal in the low-voltage line state monitoring terminal, and obtains a low-voltage transformer area branch line topological structure according to the fault working condition and the characteristic state sequence signal;

step S4, the intelligent power distribution terminal pushes the fault working condition to the position of a corresponding multi-loop low-voltage monitoring terminal or single-loop low-voltage monitoring terminal in the topological structure of the low-voltage transformer area branch line, and the position is highlighted; pushing the XML document read from the multi-loop low-voltage monitoring terminal at the highlighted position to the highlighted position;

the highlighted position is an accurate position of a low-voltage distribution area fault, and the highlighted position displays a fault working condition and account information of the faulty equipment.

Background

With the large increase of the number of power consumers, the topological structure information of the power distribution network needs to be acquired firstly in the intelligent power utilization management process. The number of users in a low-voltage transformer area is large, circuits in the transformer area are complex, and the number of circuit branches in the transformer area is large, so that accurate acquisition of fault equipment from a power grid topological structure is always a difficult problem in power supply service.

At present, the electric energy meters in a distribution area are mainly managed by means of meter reading files of a centralized meter reading system, namely, fault equipment of the low-voltage distribution area is recorded in a way of switching-off observation and meter reading data analysis by maintainers of the low-voltage distribution area, and in reality, the topological structure of the constructed distribution area is fuzzy due to the fact that the maintainers transfer or branch line transformation, so that the positioning precision of the fault equipment is reduced, meanwhile, the data are asynchronous due to the fact that delay effect exists in the meter reading process of the electric energy meters in branch lines of the distribution area, the result of fault analysis based on various asynchronous electric energy meters is inaccurate, the mode of manually judging the meter reading fault information on the whole is low in efficiency, and the accuracy is low.

Disclosure of Invention

The invention aims to provide a system and a method for accurately positioning faults of a low-voltage transformer area, and aims to solve the technical problems of low efficiency and low accuracy of a fault information judging mode in the prior art.

In order to solve the technical problems, the invention specifically provides the following technical scheme:

a low-voltage transformer area fault accurate positioning system is applied to a low-voltage transformer area and comprises a low-voltage line state monitoring terminal, an intelligent power distribution terminal and an intelligent interaction system;

the low-voltage line state monitoring terminal is positioned at each branch node of the low-voltage transformer area, and is used for measuring and freezing electric parameter data of each branch node in real time, judging fault conditions in real time and generating a characteristic state sequence signal for identifying a branch line topological structure of the low-voltage transformer area;

the intelligent power distribution terminal is in communication connection with the low-voltage line state monitoring terminal, receives the fault working condition and the characteristic state sequence signal in the low-voltage line state monitoring terminal, and carries out fault accurate positioning on a low-voltage transformer area according to the fault working condition and the characteristic state sequence signal;

the intelligent interaction system is in communication connection with the low-voltage line state monitoring terminal, and is used for inputting equipment account information of the power equipment in the low-voltage station area branch line, generating an XML document and synchronously transmitting the XML document to the low-voltage line state monitoring terminal for storage so as to realize data interaction with a target object.

Optionally, the low-voltage line state monitoring terminal includes a multi-loop low-voltage monitoring terminal, a single-loop low-voltage monitoring terminal, and a characteristic signal source;

the multi-loop low-voltage monitoring terminal is arranged on each branch box circuit of the low-voltage distribution area, the single-loop low-voltage monitoring terminal is arranged on each single meter box circuit of the low-voltage distribution area, and the characteristic signal source is arranged at the connection position of each single meter box circuit of the low-voltage distribution area and the branch meter box circuit.

Optionally, in the low-voltage line status monitoring terminal:

the multi-loop low-voltage monitoring terminal is used for measuring the electrical parameter data of the three-phase alternating current at the joint of the branch box and the branch switch in real time and collecting, metering and storing all the electrical parameter data within a preset time according to the preset time; the branch box circuit fault judgment device is used for judging working condition faults of the branch box circuit according to all the electrical parameters within a preset time length;

the single-loop low-voltage monitoring terminal is used for measuring the electric parameter data of the three-phase alternating current at the front end of the inlet switch of the single-family meter box in real time, and summarizing, metering and storing all the electric parameter data within a preset time according to the preset time; and the single-family meter box circuit is subjected to working condition fault judgment according to all the electric parameters within preset time.

Optionally, the single-family meter box circuit is connected with an A phase of three-phase alternating current at the connection of the branch meter box circuit in a sampling manner, and is connected with the characteristic signal source in a sampling manner;

the characteristic signal source is connected with the multi-loop low-voltage monitoring terminal in a sampling manner;

the real-time measurement and freezing measurement of each branch node electrical parameter data and real-time fault condition are judged to the low-voltage line state monitoring terminal, and the characteristic state sequence signal that is used for discerning low-voltage station district branch circuit topological structure is produced simultaneously, includes:

the multi-loop low-voltage monitoring terminals on the branch box lines respectively perform mutually independent capacitance switching operation and generate mutually exclusive topological module control signals;

the characteristic signal source receives a topology module control signal of the multi-loop low-voltage monitoring terminal on the same branch box line, and collects the A-phase alternating current signal according to the topology module control signal to generate a characteristic state sequence signal.

Optionally, monitoring endpoints are respectively arranged on the multi-loop low-voltage monitoring terminal and the single-loop low-voltage monitoring terminal, and the monitoring endpoints are respectively connected with the characteristic signal source and the intelligent power distribution terminal in a sampling manner;

the intelligent power distribution terminal is used for respectively and independently controlling each multi-loop low-voltage monitoring terminal to carry out mutually independent capacitance switching operation so as to generate a characteristic state sequence signal with a characteristic signal source;

the intelligent power distribution terminal is used for sampling characteristic state sequence signals of all monitoring endpoints and constructing a topology module of the monitoring endpoint where the existing characteristic state sequence signals with the same sequence are located and the characteristic signal source generating the characteristic state sequence signals;

the intelligent power distribution terminal is used for sequentially fusing the same monitoring end points of all the topology modules to generate a low-voltage distribution area branch line topology structure.

Optionally, the intelligent power distribution terminal carries out accurate location of trouble according to trouble operating mode and low-voltage platform district branch circuit topological structure, includes:

and pushing the fault working condition to the position of the corresponding multi-loop low-voltage monitoring terminal or single-loop low-voltage monitoring terminal in the topological structure of the branch line of the low-voltage platform area, and highlighting the position.

Optionally, the communication connection comprises: adopting a dual-mode communication module for communication connection;

the dual-mode communication module comprises an HPLC carrier communication unit and a wireless communication unit.

Optionally, the multi-loop low-voltage monitoring terminal includes a super energy storage capacitor, and the super energy storage capacitor is configured to provide uninterrupted power supply for the multi-loop low-voltage monitoring terminal when the multi-loop low-voltage monitoring terminal loses external power supply.

Optionally, the intelligent interactive system is configured to use a dedicated portal running on the intelligent interactive system to enter and convert equipment account information data into an XML document by scanning a two-dimensional code of the power equipment or by manual entry;

the intelligent interaction system is used for transmitting the XML document to a multi-loop low-voltage monitoring terminal which is positioned in the same topological module with the power equipment for storage;

the intelligent power distribution terminal is used for reading an XML document in the multi-loop low-voltage monitoring terminal and pushing the XML document to the position of the corresponding multi-loop low-voltage monitoring terminal or the single-loop low-voltage monitoring terminal in the branch line topological structure of the low-voltage distribution area to display for target object query.

The invention also provides a low-voltage transformer area fault accurate positioning method which is realized based on the low-voltage transformer area fault accurate positioning system and comprises the following steps:

step S1, installing the low-voltage line state monitoring terminals at each branch node of the low-voltage transformer area, inputting the equipment account information of the power equipment in the branch line of the low-voltage transformer area by using the intelligent interaction system, generating an XML document and synchronously transmitting the XML document to the low-voltage line state monitoring terminals for storage;

step S2, the low-voltage line state monitoring terminal measures the electrical parameter data of each branch node in real time, measures the freezing and judges the fault condition in real time, and generates a characteristic state sequence signal for identifying the topological structure of the branch line of the low-voltage transformer area;

step S3, the intelligent power distribution terminal receives the fault working condition and the characteristic state sequence signal in the low-voltage line state monitoring terminal, and obtains a low-voltage transformer area branch line topological structure according to the fault working condition and the characteristic state sequence signal;

step S4, the intelligent power distribution terminal pushes the fault working condition to the position of a corresponding multi-loop low-voltage monitoring terminal or single-loop low-voltage monitoring terminal in the topological structure of the low-voltage transformer area branch line, and the position is highlighted; pushing the XML document read from the multi-loop low-voltage monitoring terminal at the highlighted position to the highlighted position;

the highlighted position is an accurate position of a low-voltage distribution area fault, and the highlighted position displays a fault working condition and account information of the faulty equipment.

Compared with the prior art, the invention has the following beneficial effects:

according to the invention, the low-voltage transformer area equipment is subjected to fault condition judgment by using the low-voltage line state monitoring terminal, a characteristic state sequence signal for identifying a branch line topological structure of the low-voltage transformer area is generated at the same time, the automatic identification of the topological structure of the low-voltage transformer area is realized by using the intelligent power distribution terminal based on the characteristic state sequence signal, the accurate positioning of the low-voltage transformer area fault is realized by combining the fault condition, the time delay effect of manual meter reading is avoided, the precision and the efficiency are high, the management of the low-voltage transformer area equipment information is realized by depending on transformer account management, the loss of equipment data can be prevented, basic data support is provided for equipment maintenance, a fault processing scheme is rapidly analyzed and obtained, and the fixed-point maintenance efficiency is improved.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below. It should be apparent that the drawings in the following description are merely exemplary, and that other embodiments can be derived from the drawings provided by those of ordinary skill in the art without inventive effort.

Fig. 1 is a schematic structural diagram of a low-voltage transformer area fault accurate positioning system according to an embodiment of the present invention;

fig. 2 is a schematic structural diagram of a feature signal source and a listening endpoint according to an embodiment of the present invention;

fig. 3 is a flowchart of a method for accurately positioning a fault according to an embodiment of the present invention.

The reference numerals in the drawings denote the following, respectively:

1-low voltage line state monitoring terminal; 2-intelligent power distribution terminal; 3-an intelligent interactive system; 4-monitoring the end point;

101-a multi-loop low-voltage monitoring terminal; 102-single-loop low-voltage monitoring terminal; 103-the signature signal source.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

As shown in fig. 1, the construction of the intelligent low-voltage transformer area is an important part of the construction of the intelligent power grid, the distribution transformer area directly faces to power consumers, the existing low-voltage transformer area faces to more or less various problems, and the intelligent transformation and construction of the low-voltage transformer area can bring the following advantages: the low-voltage distribution area has the advantages that the running state of the low-voltage distribution area is monitored and controlled in real time, the topology of the power distribution area is automatically identified, power failure fault judgment and power failure fault information are actively uploaded, short-circuit faults are judged and positioned in time, the power restoration time is shortened, and the power supply reliability is improved.

Based on the above, the invention provides a low-voltage transformer area fault accurate positioning system, which comprises a low-voltage line state monitoring terminal 1, an intelligent power distribution terminal 2 and an intelligent interaction system 3.

The low-voltage line state monitoring terminal 1 is located at each branch node of the low-voltage distribution room, and is used for measuring and freezing electric parameter data of each branch node in real time, judging fault conditions in real time, and generating a characteristic state sequence signal for identifying a branch line topological structure of the low-voltage distribution room.

The low-voltage line state monitoring terminal 1 comprises a multi-loop low-voltage monitoring terminal 101, a single-loop low-voltage monitoring terminal 102 and a characteristic signal source 103, wherein the multi-loop low-voltage monitoring terminal 101 is arranged on each branch box line of a low-voltage distribution area, the single-loop low-voltage monitoring terminal 102 is arranged on each single-family meter box line of the low-voltage distribution area, and the characteristic signal source 103 is arranged at the connection position of each single-family meter box line of the low-voltage distribution area and the branch meter box line.

Multiloop low pressure monitor terminal 101 panel is equipped with 6 LED pilot lamps and includes: power indicator lamp, running light, carrier communication lamp, RS485 communication lamp, device abnormal light and circuit 1/2/3/4/5 trouble lamp for realize the instruction of various operating modes.

In one optional implementation manner of this embodiment, the colors and corresponding operating conditions of the indicator lights are as follows:

the power supply lamp is green, and represents that the main power supply of the equipment works normally when the power supply lamp is lightened.

The operating light is green, and the flashing represents that the program of the equipment operates normally.

The carrier communication lamp is green, and flashes when the carrier module has uplink and downlink data communication and is extinguished when no data communication exists.

The RS485 communication lamp is green, and flashes when the low-voltage line state monitoring terminal 1 collects data interaction of an external ammeter, and extinguishes when no data communication exists.

The device abnormal light-red is lighted when the low-voltage line state monitoring terminal 1 detects the fault and the abnormality, and the device abnormal light usually means that the equipment needs to be repaired or replaced.

The circuit fault lamp is red, and when the circuit has voltage loss, current loss, phase failure, reverse voltage sequence, reverse current sequence and short circuit fault, the corresponding indicator lamp is lighted. And when the working condition or the fault is recovered, the corresponding line fault indicator lamp is turned off.

There are also 6 pilot lamps on single loop low pressure monitor terminal 102 panel, include: operation/alarm, active power, uplink communication, RS-485I and RS-485II communication indicator lamps and fault indicator lamps.

Specifically, the running/warning indicator light-running state indicator light is red and green, and the indicator light is always bright green to indicate normal running; when the USB flash disk is used for program upgrading, the indication lamp alternately flashes red and green to indicate that the upgrading is in progress, and the indication lamp flashes red to indicate that the upgrading fails.

The active lamp-active pulse output indicator lamp is red, and the lamp normally flickers when the meter is checked.

The uplink communication lamp-uplink communication state indicator lamp has two colors of red and green, wherein the red light flickers to indicate that the uplink channel of the low-voltage line monitoring terminal receives data, and the green light flickers to indicate that the uplink channel of the low-voltage line monitoring terminal sends data.

The RS-485I communication lamp-RS-485I circuit communication status indicator lamp has two colors of red and green, wherein the red light flickers to indicate that the low-voltage circuit monitoring terminal receives data, and the green light flickers to indicate that the low-voltage circuit monitoring terminal sends data.

The RS-485II communication lamp-RS-485 II road communication status indicator lamp has two colors of red and green, wherein the red light flickers to indicate that the low-voltage line monitoring terminal receives data, and the green light flickers to indicate that the low-voltage line monitoring terminal sends data.

The fault lamp is red, namely a fault indicator lamp, and is normally on when the voltage, the current loop and the like are detected to be abnormal (such as overvoltage, overcurrent and the like).

The intelligent power distribution terminal 2 is in communication connection with the low-voltage line state monitoring terminal 1, receives fault working conditions and characteristic state sequence signals in the low-voltage line state monitoring terminal 1, and carries out fault accurate positioning on the low-voltage transformer area according to the fault working conditions and the characteristic state sequence signals.

And the intelligent interaction system 3 is in communication connection with the low-voltage line state monitoring terminal 1, and the intelligent interaction system 3 is used for inputting the equipment account information of the power equipment in the low-voltage branch line, generating an XML document and synchronously transmitting the XML document to the low-voltage line state monitoring terminal 1 for storage so as to realize data interaction with a target object.

Specifically, intelligent interactive system 3 provides the generation of equipment account information file, save and send the function on, equipment account information file format is XML, when generating the engineering installation by engineering installer when on-the-spot engineering installation, by engineering installer operation special APP on cell-phone/flat board, through modes such as scanning equipment two-dimensional code and manual type, equipment account information data generation XML document such as equipment producer, model, specification, date of production, maintenance information, and transmit to low pressure multichannel monitoring unit through the bluetooth and save, intelligent power distribution terminal 2 can acquire this equipment account information file through carrier wave or radio communication at any time.

The method comprises the following specific steps of measuring electrical parameter data in real time, measuring freezing and judging fault conditions in real time:

the multi-loop low-voltage monitoring terminal 101 measures the electrical parameter data of the three-phase alternating current at the joint of the branch box and the branch switch in real time, and collects, measures and stores all the electrical parameter data within a preset time length according to the preset time length;

the single-loop low-voltage monitoring terminal 102 measures the electric parameter data of the three-phase alternating current at the front end of the inlet switch of the single-family meter box in real time, and collects, measures and stores all the electric parameter data within a preset time length according to the preset time length;

the multi-loop low-voltage monitoring terminal 101 and the single-loop low-voltage monitoring terminal 102 respectively perform working condition fault judgment on the branch box circuit and the single-family meter box circuit according to all electric parameters within preset time.

The real-time measurement of the electrical parameter data comprises the real-time measurement of three-phase voltage and current, active power, reactive power, apparent power and grid frequency, the real-time measurement of the harmonic distortion rate and the 2-21 harmonic content of the three-phase voltage and current, the measurement of three-phase active/reactive electric energy can be realized, and the real-time demand of the active and reactive electric energy of the three phases is measured by forward and reverse harmonic active electric energy, so that the maximum reactive demand of the three phases and the occurrence time of the three phases are recorded.

The preset time length can be set as required in actual use, the electric parameters are frozen according to the preset time length, the intelligent power distribution terminal 2 can be guaranteed to obtain the electric energy, the current power and other data of each branch node at the same time, the synchronism of the data of each branch node is kept, data deviation caused by delay effect is avoided, and the accuracy of a fault analysis result is finally improved.

The characteristic signal source 103 is respectively connected with the multi-loop low-voltage monitoring terminal 101 and the A phase sampling in the three-phase alternating current at the joint of the single-family meter box line and the branch meter box line, and the specific steps of generating the characteristic state sequence signal comprise:

the multi-loop low-voltage monitoring terminals 101 on the lines of the branch boxes respectively perform mutually independent capacitance switching operation and generate mutually exclusive topological module control signals;

the characteristic signal source 103 receives a topology module control signal of the multi-loop low-voltage monitoring terminal 101 on the same branch box line, and generates a characteristic state sequence signal according to an A-phase alternating current signal acquired by the topology module control signal;

the mutual exclusion means that each topology module has an independent and unique topology module control signal.

The capacitor switching is short-time switching (maintained within tens of milliseconds), the influence on a power grid can be ignored, a specific topological module control signal of the reactive state sequence is formed according to the switching length and the existence of the switching, the identifiability and the anti-interference capability are good, and the obtained characteristic state sequence signal also has good identifiability and the anti-interference capability.

As shown in fig. 2, monitoring endpoints 4 are respectively disposed on the multi-loop low-voltage monitoring terminal 101 and the single-loop low-voltage monitoring terminal 102, the monitoring endpoints 4 are respectively connected with the characteristic signal source 103 and the intelligent power distribution terminal 2 in a sampling manner, and the specific steps of the intelligent power distribution terminal 2 generating the branch line topology structure of the low-voltage transformer area according to the characteristic state sequence signal include:

the intelligent power distribution terminal 2 respectively and independently controls each multi-loop low-voltage monitoring terminal 101 to carry out mutually independent capacitance switching operation so as to generate a characteristic state sequence signal with the characteristic signal source 103;

the intelligent power distribution terminal 2 samples characteristic state sequence signals of all the monitoring endpoints 4, and constructs a topological module of the monitoring endpoint 4 where the existing characteristic state sequence signals with the same sequence are located and a characteristic signal source 103 generating the characteristic state sequence signals;

the intelligent power distribution terminal 2 sequentially fuses the same monitoring end points 4 of all the topology modules to generate a low-voltage distribution area branch line topology structure.

The specific steps of carrying out accurate fault positioning on the intelligent power distribution terminal 2 according to the fault working condition and the low-voltage transformer area branch line topological structure comprise:

the intelligent power distribution terminal 2 pushes the fault working condition to the position of the corresponding multi-loop low-voltage monitoring terminal 101 or single-loop low-voltage monitoring terminal 102 in the low-voltage distribution area branch line topological structure to be highlighted.

The communication connection is realized by adopting a dual-mode communication module, and the dual-mode communication module comprises an HPLC carrier communication unit and a wireless communication unit.

The low-voltage line state monitoring terminal 1 is provided with 1 local RS485 communication port (2400 bps, even check), 1 local RS232 maintenance port (19200 bps, no check) and 1 dual-mode (HPLC carrier + wireless) communication module, and can be replaced by a full-network communication 4G module to directly communicate with a low-voltage station main station (applicable to small-scale stations) according to field application conditions, so that the intelligent power distribution terminal 2 is not needed. The communication ports are independent of each other at the physical layer, and damage to one communication channel does not affect the other. In addition, the communication interface and the internal circuit of the equipment are electrically isolated, and a failure protection circuit is arranged.

And the local RS485 interface is used for externally acquiring information. The local RS232 interface is used for performing engineering maintenance, such as XML file transmission, parameter setting, program upgrading, and the like, on the low-voltage line state monitoring terminal 1.

The dual-mode communication module is used for communicating with the intelligent power distribution terminal 2 through HPLC carrier waves and wireless communication.

The multi-loop low-voltage monitoring terminal 101 is further internally provided with a super energy storage capacitor, and the super energy storage capacitor is used for providing uninterrupted power supply for the multi-loop low-voltage monitoring terminal 101 under the condition that the multi-loop low-voltage monitoring terminal 101 loses external power supply so that fault working conditions can be normally transmitted to the intelligent power distribution terminal 2.

The specific steps of inputting equipment account information and generating an XML document comprise:

the method comprises the steps that a special portal running on an intelligent interactive system 3 is utilized, and the equipment account information data are recorded and converted into XML documents in a mode of scanning two-dimensional codes of power equipment or manually recording;

the intelligent interactive system 3 transmits the XML document to a multi-loop low-voltage monitoring terminal 101 which is in the same topological module with the power equipment for storage;

the intelligent power distribution terminal 2 reads the XML document in the multi-loop low-voltage monitoring terminal 101, and pushes the XML document to the position of the branch line topological structure of the low-voltage transformer area corresponding to the multi-loop low-voltage monitoring terminal 101 or the single-loop low-voltage monitoring terminal 102 for being displayed for target object query.

The XML document of the fault equipment is pushed to the fault equipment to be displayed, data support is provided for maintenance personnel, the maintenance personnel can conveniently and rapidly analyze the fault solution according to the data support, time consumption caused by self acquisition of the maintenance personnel is avoided, and therefore overhaul efficiency is improved.

As shown in fig. 3, based on the structure of the accurate positioning system for faults in a low-voltage transformer area, the invention provides an accurate positioning method for faults, which includes the following steps:

step S1, installing the low-voltage line state monitoring terminal 1 at each branch node of the low-voltage distribution room, inputting the equipment account information of the power equipment in the branch line of the low-voltage distribution room by using the intelligent interaction system 3, generating an XML document, and synchronously transmitting the XML document to the low-voltage line state monitoring terminal 1 for storage;

step S2, the low-voltage line state monitoring terminal 1 measures the electrical parameter data of each branch node in real time, measures the freezing and judges the fault condition in real time, and generates a characteristic state sequence signal for identifying the branch line topological structure of the low-voltage transformer area;

step S3, the intelligent power distribution terminal 2 receives the fault working condition and characteristic state sequence signal in the low-voltage line state monitoring terminal 1, and obtains a branch line topological structure of the low-voltage transformer area according to the fault working condition and characteristic state sequence signal;

step S4, the intelligent power distribution terminal 2 pushes the fault working condition to the position of the corresponding multi-loop low-voltage monitoring terminal 101 or single-loop low-voltage monitoring terminal 102 in the branch line topological structure of the low-voltage transformer area to be highlighted, and the XML document read from the multi-loop low-voltage monitoring terminal 101 at the highlighted position is pushed to the highlighted position;

the highlighted display position is an accurate position of a low-voltage distribution area fault, and the fault working condition and the account information of the fault equipment are displayed so that the target object can inquire and the fault equipment can be maintained at a fixed point.

According to the invention, the low-voltage transformer area equipment is subjected to fault condition judgment by using the low-voltage line state monitoring terminal 1, a characteristic state sequence signal for identifying a branch line topological structure of the low-voltage transformer area is generated at the same time, the intelligent power distribution terminal 2 is used for realizing automatic identification of the topological structure of the low-voltage transformer area based on the characteristic state sequence signal, accurate positioning of low-voltage transformer area faults is realized by combining fault conditions, the time delay effect of manual meter reading is avoided, the precision is high, the efficiency is high, the management of the low-voltage transformer area equipment information is realized by depending on transformer account management, the loss of equipment data can be prevented, basic data support is provided for equipment maintenance, a fault processing scheme is rapidly analyzed and obtained, and the fixed-point maintenance efficiency is improved.

The above embodiments are only exemplary embodiments of the present application, and are not intended to limit the present application, and the protection scope of the present application is defined by the claims. Various modifications and equivalents may be made by those skilled in the art within the spirit and scope of the present application and such modifications and equivalents should also be considered to be within the scope of the present application.