CN212231096U - Power distribution station topology identification system - Google Patents

Abstract

The utility model relates to a distribution station district topology identification system. A distribution area topology identification system is composed of an area transformer, a plurality of intermediate devices and a plurality of terminal devices on an area distribution line according to the area relationship in the area; the terminal equipment is provided with a terminal topology injection module; the intermediate equipment is provided with an inter-topology receiving module and an inter-topology injecting module; the transformer area is provided with a transformation topology receiving module. The system constructs a set of platform area topology recognition system, a topology injection module actively sends current pulse signals of equipment information of the equipment, the current pulse signals can sequentially pass through intermediate equipment on a line along a network-level venation structure and are received by a topology receiving device, the intermediate equipment sends the current pulse signals of the equipment information of the equipment again, the analogy is carried out in sequence, and a transformer of a platform area at the last stage receives all topology signals, so that the platform area topology structure is automatically recognized.

Description

Power distribution station topology identification system

Technical Field

The utility model relates to a distribution network management field especially relates to a distribution station district topology identification system.

Background

At present, with the increasingly strict requirements of the national grid company on the fine management of the panoramic perception of the low-voltage distribution network, how to comprehensively perfect the management of the low-voltage distribution network, identify the home topological relations between the distribution network and the meter box and between the branches and the meter box, realize the real-time and accurate report of the topological structures, and realize the full through of the relation of variable-line-branch-meter box becomes an important guarantee basis for realizing the fine management requirements of the panoramic perception of the low-voltage distribution network. The reliability of topological relation information cannot be guaranteed due to technical and management problems of the existing low-voltage power distribution network, unified digital storage cannot be realized, and a unified interface is not provided for further utilization of other systems and applications, so that the problems of safety fault points, line loss abnormal points and the like related to the faults of the line are low in troubleshooting efficiency, long in period and high in cost. Therefore, the automatic identification of the topological relation of each node device (including a transformer area, a branch, a meter box and a household meter) of the low-voltage distribution network is realized, and the key point for solving the problems is to realize the automatic identification of the topological relation of each node device of the low-voltage distribution network.

Patent document ZL201910857146.0 discloses a topology and line impedance identification method for a transformer area low-voltage power distribution network, and belongs to the technical field of low-voltage power distribution networks. The method comprises the steps that firstly, an edge computing terminal and a plurality of electrical measuring devices are added in a low-voltage distribution network of a transformer area; when the topology of the low-voltage distribution network of each distribution area is identified, the affiliation relationship of the distribution area of the measuring device and the phase of a communication access phase are determined according to the power line carrier communication relationship between the measuring device and the edge computing terminal, each measuring device and the edge computing terminal perform time synchronization, then voltage and current waveform sampling is performed, the voltage and current waveform sampling is uploaded to the edge computing terminal, and the edge computing terminal identifies the same bus measuring device and a bus higher-level measuring device according to waveform data; and after multiple times of topology identification, obtaining a final topology identification result and carrying out impedance calculation. The method has high accuracy and high speed for identifying the topology and the line impedance of the low-voltage distribution network, fully utilizes the information acquisition capability of intelligent equipment of the low-voltage distribution network, has low equipment cost and has no influence on the quality of electric energy.

Patent document ZL201910380685.X discloses a method and a system for automatically identifying distribution room topology, and belongs to the technical field of electric low-voltage power distribution networks. On the basis of determining the topological relation between the upper and lower levels of each branch, the invention determines the inlet end of each branch based on the fact that the current of the inlet end of each branch is the sum of the currents of the outlet ends of the branches, and determines the connection relation between the inlet and outlet lines of different branches according to the principle that the currents of the outlet ends of the branches are equal to the currents of the inlet ends of the branches of the next level, thereby determining the connection relation between the branches. The above process can effectively avoid the problems of communication crosstalk in a power frequency communication mode and unsafe and high interference in a pulse communication mode, and improves the accuracy of topology identification.

The existing node equipment topology identification method in the field of low-voltage distribution networks is a method based on power line carrier communication, and a main computing terminal and a plurality of electrical measurement devices are added in a low-voltage distribution network of a transformer area; when the topology of the low-voltage distribution network in the transformer area is identified each time, the attribution relationship of the transformer area of the measuring device and the phase of a communication access phase are determined according to the power line carrier communication relationship between the measuring device and a main computing terminal, after each measuring device and the main computing terminal are synchronized in time, the main computing terminal sends inquiry instructions to each branch line and a tail end measuring device, and the main computing terminal identifies the same bus measuring device and a bus superior measuring device according to address information returned by each branch line and the tail end measuring device; and obtaining final topology identification after multiple times of topology identification. The method has the disadvantages that the method is easily influenced by the common ground of the transformer, carrier signals cannot be completely isolated by the transformer in practical application, and the carrier signals can still be coupled to other transformer areas to generate cross-area identification crosstalk, so that identification misjudgment is caused, and the accuracy is low.

Therefore, the existing detection of the information of the house line relationship file still has defects and needs to be improved and enhanced.

SUMMERY OF THE UTILITY MODEL

In view of the weak point of the above-mentioned prior art, the utility model aims to provide a distribution station district topology identification system can solve when the discernment carries out the district topological relation and confirms, probably has the erroneous judgement, leads to the problem that the rate of accuracy is not high.

In order to achieve the purpose, the utility model adopts the following technical proposal:

a distribution area topology identification system is composed of an area transformer, a plurality of intermediate devices and a plurality of terminal devices on an area distribution line according to the area relationship in the area; wherein,

the terminal equipment is provided with a terminal topology injection module; the intermediate equipment is provided with an inter-topology receiving module and an inter-topology injecting module; the transformer area is provided with a transformation topology receiving module.

In the preferred power distribution area topology identification system, the terminal topology injection module and the inter-topology injection module are the same topology injection module;

the topology injection module comprises an injection zero-crossing detection unit, an injection current sampling unit, a pulse injector and an injection manager; the injection zero-crossing detection unit, the injection current sampling unit and the pulse injector are all connected on the same distribution line and are respectively connected with the injection manager.

Preferably, in the distribution substation topology identification system, the intermediate device further includes a data synthesis module; the data synthesis module is respectively connected with the inter-topology receiving module and the inter-topology injection module.

Preferably, in the power distribution area topology identification system, the inter-topology receiving module and the transformation topology receiving module are the same topology receiving module;

the topology receiving module includes: the monitoring system comprises a pulse detection unit, a monitoring manager, a monitoring zero-crossing detection unit and a monitoring current sampling unit; the pulse detection unit, the monitoring zero-crossing detection unit and the monitoring current sampling unit are respectively connected with the monitoring manager.

Compared with the prior art, the utility model provides a distribution station area topology identification system, this system found a set of station area topology identification system, and intermediate device and terminal equipment are located each node position of station district circuit, and the station district transformer is located the incoming line side of low voltage station district, and intermediate device is from taking topology injection, receiving module, and terminal equipment takes topology injection module, and the station district transformer takes topology receiving module; the topology injection module actively sends current pulse signals of the equipment information of the equipment, the current pulse signals can follow the network-level venation structure to sequentially pass through the intermediate equipment on the line and are received by the topology receiving device, the intermediate equipment sends the current pulse signals of the equipment information of the equipment again, the analogy is repeated, and the transformer of the last stage of the platform area receives all the topology signals, so that the automatic identification of the platform area topology structure is realized.

Drawings

Fig. 1 is a schematic block diagram of a topology identification system of a power distribution area provided by the present invention;

FIG. 2 is a block diagram of a topology injection module provided by the present invention;

fig. 3 is a block diagram of a topology receiving module provided by the present invention;

fig. 4 is a block diagram of an embodiment of a topology identification system for a distribution substation provided by the present invention;

fig. 5 is a flowchart of a power distribution grid topology identification method provided by the present invention.

Detailed Description

In order to make the objects, technical solutions and effects of the present invention clearer and clearer, the following description of the present invention will refer to the accompanying drawings and illustrate embodiments. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the invention.

Referring to fig. 1-5, the present invention provides a distribution area topology identification system, which is composed of an area transformer 1, a plurality of intermediate devices 2, and a plurality of terminal devices 3 on an area distribution line according to the area relationship; wherein,

the terminal device 3 is provided with a terminal topology injection module; the intermediate device 2 is provided with an inter-topology receiving module and an inter-topology injecting module; the transformer 1 has a transformation topology receiving module.

Specifically, the utility model provides an among the distribution station district topology identification system the station district transformer intermediate device with terminal equipment is through having topology injection module and/or topology receiving module cooperation separately and use, and specific method does not do the injeciton, as long as can realize using provide in this system terminal topology injection module between topology injection module, between topology receiving module and the cooperation of vary voltage topology receiving module is used, reaches the effect of constructing distribution station district topology information.

Preferably, the utility model also provides a be suitable for distribution board district topology identification method of distribution board district topology identification system, its characterized in that includes the step:

s1, the terminal device 3 injects a terminal current pulse signal into the distribution line;

s2, the intermediate device 2 monitors and demodulates the current pulse signals transmitted by the distribution line, and injects new current pulse signals into the distribution line after demodulation;

and S3, monitoring and demodulating the current pulse signals in the distribution lines by the transformer 1 of the distribution area, and generating a topological relation table of the distribution area.

Under the general condition, have a platform district transformer 1, multistage intermediate installation 2 (branch case at all levels) in a platform district a plurality of intermediate installation 2, a plurality of terminal equipment 3, wherein intermediate installation 2 is platform district discernment appearance, branch case etc. and terminal equipment 3 is ammeter case etc. installs in the ammeter case as to the electric energy meter of registering one's residence to the discernment of its family's affiliation is the topology management between power supply line and the electric energy meter, does not belong to the utility model discloses technical scheme that protects, the utility model discloses technical scheme that protects mainly is the affiliation between intermediate installation 2 and the terminal equipment 3 at all levels in the platform district, convenient management. Specifically, when the distribution substation needs to follow a new intra-substation topology relationship table, the terminal device 3 will start to execute step S1; therefore, before step S1, step S0 is further included, and the station transformer 1 sequentially transmits the recall signal to each terminal device 3. Correspondingly, the terminal device 3 (e.g. a meter box), the intermediate device 2 (e.g. a branch box) and the platform transformer 1 are all provided with communication modules, and it should be noted herein that, in practical use, the terminal device 3, the intermediate device 2 and the platform transformer 1 all include communication modules, which are common knowledge in the art, and are used for data communication with each other; as for each time that terminal device 3 executes the method, the setting is specifically set according to the field situation, and is not limited.

Specifically, in step S2, the intermediate devices 2 belong to different classes, that is, there are corresponding affiliations among a plurality of intermediate devices 2, and all of the intermediate devices are used to monitor and demodulate the current pulse signals in the connected power distribution lines, and it should be noted here that, in order to avoid data confusion, the lengths of the lower signals that each of the intermediate devices 2 needs to monitor are different, and the operation is performed according to step S2 only when the current pulse signals transmitted by the lower intermediate devices 2 are monitored. In step S3, the transformer 1 of the distribution room does not need to send a current pulse signal, but only needs to monitor a pulse signal in a line, and manages the topological relation of the distribution room by demodulating all received current pulses.

Please refer to fig. 4, in this embodiment, the topology structure of the distribution substation is divided into four layers, namely, a substation transformer-branch switch box (1.a) -branch switch box (1.a.1/1.a.3) -meter box (1.a.1.1/1.a.1.2, etc.), wherein if the electric meter is used as the terminal device 3, the topology structure in this embodiment is five layers. The first layer of transformer, namely the transformer low voltage output line side, is connected to the line layer, 1 intelligent distribution terminal is arranged on the outgoing line side of the transformer, and is used for monitoring all topology sending signals of the whole transformer area, analyzing the signals and automatically generating a transformer area topology map, and the address code is '1';

the middle layer 'line', namely the area from the back of the outgoing line side of the transformer to the incoming line of the meter box, can be divided into one layer or two layers of upper and lower level relations according to the structural complexity of different transformer areas, in this example, the upper and lower level relations are taken, namely the middle layer 1 and the middle layer 1.X, the nodes of the middle layer 1 and the middle layer 1.X are respectively provided with the same branch monitoring terminal for monitoring and sending the topological signals of each node of the middle layer line, and the nodes are respectively represented by address codes '1. A', '1. A.1', '1. A.2' and '1. A.3';

the meter box layer meter is a meter box outlet wire area of the meter box inlet wire, 1 meter box monitoring terminal is attached to the inlet wire side of each meter box and used for sending topological signals of the nodes of the meter box, and the address codes are 1.A.1.1 "," 1.A.1.2 "," 1.A.3.1 "," 1.A.3.2 "and the like;

the last layer of "house" is a switch from the outgoing line of each house of the meter box to the load of the user entering the house, each house is provided with 1 tail end node, and the address is represented by "1. A.1.1. X";

after the device assignment of the whole platform area is completed, the topological address signal is sent from bottom to top, for example; the first-level address of the household meter 1.A.1.1.X is uploaded to a meter box monitoring terminal topology transmitting device in the meter box through 485, the device packages the address information of the household meter as subclasses of the node to generate a meter box layer packet address 1.A.1.1&1.A.1.1.X …, then pulse current address signals of the packet address are injected into a line at a meter box inlet line, the topology address information is uploaded to a node on the branch, the node is a junction point of the circuit and other meter box terminal topology transmitting devices, in the example, a middle 2 layer is arranged, the node is provided with a branch monitoring terminal topology transmitting and receiving device, the function of the branch monitoring terminal topology transmitting and receiving device is mainly used for monitoring and acquiring the pulse current address signals injected into a meter box terminal topology transmitting device (2 in the node) at the lower end of the circuit, when the signals are integrated and belong to the address signals of the node, the branch layer packet address 1.A.1&1.A.1.1&1.A.1. A.1.1.1. A.1.1.1.1. X …' is injected into the branch circuit topology transmitting device, and A The pulse current address signal of the branch layer packet address is unidirectional in the flowing direction of the current signal, namely from top to bottom, because the current sources of the low-voltage station area are only 1 (transformer), so that the receiving devices of the same layer but different nodes do not receive the signals of other nodes of the same layer, and only the upper layer can receive the signals, namely the middle 1 layer branch monitoring terminal of the topology address "1. A" is subjected to the branch layer packet address "1. A.1& 1.A.1.1.X …" sent by the middle 2 layer. The intermediate layer 1 integrates these signals, and belongs to its own address signal, and generates a branch layer packet address "1. a &1.a.1&1.a.1.1&1. a.1.1.1. x …" as a subclass, and then injects a pulse current address signal of the generated branch layer packet address into a branch line node of the intermediate layer 1 through a transmission module. And in the same way, finally, the first-layer equipment, namely the intelligent distribution transformer terminal topology identification receiving device monitors and receives all pulse current address signals sent by all the next-level branch terminal topology sending devices, collects all the address information, adds the self topology address information into the address information, generates a first-layer topology information packet address of 1&1.A &1.A.1& 1.A.1.1.X …', and automatically generates a complete topology map of the transformer area according to the recursion relation of the information addresses and uploads the complete topology map to the master station.

As a preselected scheme, in this embodiment, the terminal topology injection module and the inter-topology injection module are the same topology injection module;

the topology injection module comprises an injection zero-crossing detection unit 11, an injection current sampling unit 12, a pulse injector 13 and an injection manager 14; the injection zero-crossing detection unit 11, the injection current sampling unit 12 and the pulse injector 13 are all connected to the same distribution line and are respectively connected to the injection manager 14. The injection zero-crossing detection unit 11, the injection current sampling unit 12, the pulse injector 13 and the injection manager 14 are all common components in the field; the injection manager 14 drives the injection zero-cross detection unit 11, the pulse injector 13 and the injection current sampling unit 12 to operate according to steps S11-S13, respectively, but may inject pulses using other pulse injection methods in the art.

Correspondingly, the utility model provides an among the distribution board district topology identification method, in step S1 and step S2, when injecting current pulse signal at every turn, all inject a lot of current pulse signal, the step of injecting current pulse signal at every turn includes:

s11, an injection zero-crossing detection unit 11 detects cycle zero-crossing data of current cycles in a distribution line, an injection current sampling unit 12 detects current sampling data in a primary distribution line at intervals of first preset time, and the cycle zero-crossing data and the current sampling data are sent to an injection manager 14;

s12, after the injection manager 14 performs a predetermined number of current sampling points, the driving pulse injector 13 writes a current pulse;

s13, the injection manager 14 determines whether the current pulse signal is injected completely, and if so, stops injecting; if not, step S11 is executed.

Specifically, the injection manager 14 stores the device information of the device, and when injection is needed, the device information is expressed by using a current pulse signal in a conversion manner, specifically, current pulses are injected on a plurality of current cycles, and the current pulse signal is modulated, wherein the preferred time length of each current pulse is 50 microseconds, and the preferred current pulses are injected on the positive half wave of the current cycle; the first predetermined time is 1/18 (i.e., 360 current cycle detections) milliseconds. In step S12, the predetermined number is set according to the field requirement and the type of the cycle zero-crossing data, and in general, the voltage cycle of the alternating current is formed in a sine-like state, so the types of the cycle zero-crossing points are divided into a negative zero-crossing point (i.e. after zero-crossing, the current direction is a negative half-wave of the cycle) and a positive zero-crossing point (i.e. after zero-crossing, the current direction is a positive half-wave of the cycle), if in actual use, the current direction is mainly detected as the positive zero-crossing point, the predetermined number is preferably 165, and if the current direction is mainly detected as the negative zero-crossing point, the predetermined number is preferably 345.

Preferably, in this embodiment, the intermediate device 2 further includes a data synthesis module (not shown); the data synthesis module is respectively connected with the inter-topology receiving module and the inter-topology injection module. The data synthesis module is configured to connect the device information of the apparatus with the received current pulse signal data sent by the next-stage device, and the apparatus with a data synthesis function commonly used in the art is used, which is not particularly limited.

Preferably, the terminal device 3 and the intermediate device 2 have the same device information length, but the lengths of the transmitted current pulse signals are different, and the current pulse signal transmitted by the intermediate device 2 includes device information of the lower intermediate device 2 or the terminal device 3.

As a preferred solution, in this embodiment, the inter-topology receiving module and the voltage transformation topology receiving module are the same topology receiving module;

the topology receiving module includes: the monitoring device comprises a pulse detection unit 21, a monitoring manager 22, a monitoring zero-crossing detection unit 23 and a monitoring current sampling unit 24; the pulse detection unit 21, the monitoring zero-crossing detection unit 23, and the monitoring current sampling unit 24 are respectively connected to the monitoring manager 22. The pulse detection unit 21, the monitoring manager 22, the monitoring zero-cross detection unit 23, and the monitoring current sampling unit 24 are all common electronic components in the art, and are not limited in particular. Preferably, the pulse detection unit 21 is configured to detect whether a current pulse exists in the distribution line, and send a detection result to the monitoring manager 22 when the current pulse is detected, which is a commonly used technical means in the field and is not described in detail herein; the monitoring manager 22 uses an MCU commonly used in the art, and the specific model and type are not limited; the listening zero-crossing detecting unit 23 is configured to detect a zero-crossing point of a cycle (voltage cycle) and transmit the cycle to the listening manager 22. The monitoring current sampling unit 24 samples in the distribution line according to the instruction of the monitoring manager 22, and transmits a sampling signal to the monitoring manager 22, and the monitoring manager 22 starts counting.

Accordingly, in the topology identification method provided by the present invention, the monitoring of the current pulse signal can be processed by other methods capable of monitoring or detecting the current pulse in the art, and preferably in step S2 and step S3, the step of monitoring the current pulse signal includes:

s21, the pulse detection unit 21 detects the current pulse in the distribution line, and if the current pulse is detected, the detection result is sent to the monitoring manager 22;

s22, the monitoring manager 22 drives the monitoring zero-crossing detection unit 23 to detect the forward zero-crossing point of the voltage signal in the power distribution line, drives the monitoring current sampling unit 24 to detect the current sampling data in the primary power distribution line at intervals of the first predetermined time, and receives the forward zero-crossing point data and the current sampling data;

and S23, taking the two current pulse signals to perform wavelet construction calculation to obtain signal data of the current pulse signals.

Preferably, in step S23, the step of calculating the constructed wavelet is:

s231, taking a plurality of current cycles in the first current pulse signal as a first wavelet set, and taking a plurality of current cycles in the second current pulse signal as a second wavelet set;

s232, dividing the frequency band with gentle current background harmonics of the low-voltage transformer area into two intervals to obtain mapping data of each interval, namely a first interval mapping and a second interval mapping; preferably, the frequency range with gentle current background harmonics is preferably 150-1000 Hz;

s233, processing by using a structural wave formula to obtain a structural wavelet set, and extracting characteristic values of the structural wavelet set by using a Daubechies wavelet basis algorithm; the structural wave formula is as follows:

ψ＝h₁w₁+h₁w₂；

wherein psi is a constructed wavelet set; w is a₁Is a first wavelet set; w is a₂A second set of wavelets; h is₁Mapping the first interval; h is₁Mapping for a second interval;

s234, judging whether the characteristic value is effective or not, and if so, determining signal data of the current pulse signal; otherwise, the current pulse signal is not detected, and step S21 is performed.

Specifically, the Daubechies wavelet basis algorithm is a known algorithm in the field, and is not described herein in detail; the method adopts a pulse current injection type signal topology identification technology, because the field environment of a low-voltage transformer area is complex and changeable, the injection type signal can be interfered by background current harmonics based on the pulse current, the method for modulating and demodulating the modulation signal is the key for improving the identification accuracy, the method adopts a pulse current identification algorithm for constructing wavelet transformation, extracts characteristic signals from the background environment with serious harmonics, overcomes the defects of frequency aliasing and frequency spectrum leakage of Fourier transformation, does not require the integrity of the signal, extracts local characteristics on the time domain and the frequency domain of the signal, extracts amplitude-frequency information on each frequency sub-segment of an incomplete target signal, obtains an adjustable 'flexible window' by utilizing scale expansion through the height of the signal frequency, eliminates the interference, identifies some sudden and aliasing signals and improves the identification accuracy.

The constructed wavelet set psi adopts Daubechies wavelet basis DB4 to realize feature extraction of feature signals, and the decomposition level is 2 layers, and the specific conditions are as follows:

detail coefficient d of topological signal under ith decomposition scale_i+1,kAnd approximation coefficient c_i+1,kComprises the following steps:

wherein h (n) c_i,n+2kFor signal frequency, g (n) c_i,n+2kN is the amplitude-frequency information value.

After the constructed wavelet set psi is processed by using Daubechies wavelet basis DB4, approximate components and detail components of the constructed wavelet set psi are obtained, and feature signals are extracted according to comparison and comparison of the detail components and empirical threshold values. The above calculation process is a common technique in the art, and is not limited and not described in detail.

In addition, considering the requirement of data accuracy, when injecting the current pulse signal every time, the data of the first two current cycles are only used as the monitoring threshold, so that the pulse detection unit 21 can detect the current pulse, and the utility model provides a current pulse signal monitoring operation S21-S23 is further used. In this case, of course, in the step of listening for the current pulse signal, in step S231, the previous one or two current cycles need to be omitted to construct the first wavelet set and the second wavelet set.

It should be understood that equivalent alterations and modifications can be made by those skilled in the art according to the technical solution of the present invention and the inventive concept thereof, and all such alterations and modifications should fall within the scope of the appended claims.

Claims (4)

1.A distribution area topology identification system is characterized by comprising an area transformer, a plurality of intermediate devices and a plurality of terminal devices on an area distribution line according to the area relationship in the area; wherein,

the terminal equipment is provided with a terminal topology injection module; the intermediate equipment is provided with an inter-topology receiving module and an inter-topology injecting module; the transformer area is provided with a transformation topology receiving module.

2. The power distribution substation topology identification system of claim 1, wherein the terminal topology injection module and the inter-topology injection module are the same topology injection module;

the topology injection module comprises an injection zero-crossing detection unit, an injection current sampling unit, a pulse injector and an injection manager; the injection zero-crossing detection unit, the injection current sampling unit and the pulse injector are all connected on the same distribution line and are respectively connected with the injection manager.

3. The power distribution substation topology identification system of claim 2, wherein the intermediate device further comprises a data synthesis module; the data synthesis module is respectively connected with the inter-topology receiving module and the inter-topology injection module.

4. The power distribution substation topology identification system of claim 1, wherein the inter-topology receiving module and the transformation topology receiving module are the same topology receiving module;

the topology receiving module includes: the monitoring system comprises a pulse detection unit, a monitoring manager, a monitoring zero-crossing detection unit and a monitoring current sampling unit; the pulse detection unit, the monitoring zero-crossing detection unit and the monitoring current sampling unit are respectively connected with the monitoring manager.

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