A distribution network topology identification system based on HPLC and NB-IoT dual-mode communication

Abstract

The present invention provides a distribution network topology identification system based on HPLC and NB‑IoT dual-mode communication, including a channel selection module connected to the signal between the smart meter, the channel selection module is connected to the HPLC module and the NB‑IoT module respectively; the HPLC module is connected to the signal between the HPLC concentrator and the power supply main station, the power supply main station is connected to the topology identification front-end machine by the signal connection, the NB‑IoT module is connected to the topology identification front-end machine through the operation platform, and the front-end machines are connected; the topology identification front-end machine performs topology identification on the information, analyzes the results, and transmits the results to the power supply main station to complete the distribution network topology structure identification. The smart meter in the present invention is connected to the channel selection module, the channel selection module is connected to the HPLC module and the NB‑IoT module respectively, the HPLC module and the NB‑IoT module are used to realize the distribution network topology identification, and the power outage reporting function of the smart meter can also be realized. The network clock of the NB‑IoT module is used to realize the independent high-precision comparison of the smart meter, which is convenient and practical.

Description

Technical Field

[0001] The present invention belongs to the technical field of low-voltage distribution network topology identification methods, and specifically relates to a distribution network topology identification system based on HPLC and NB-IoT dual-mode communications. Background Art

[0002] With the development of power grid state estimation technology, power system topology analysis methods have received widespread attention from experts and scholars. Traditional power system topology analysis methods generally express the topology as a linked list relationship and use search techniques in graph theory, such as depth-first search and breadth-first search, to analyze the connectivity of nodes. This method generally requires the establishment of a linked list reflecting the topology structure and the topology analysis is achieved by processing the linked list.

[0003] The low-voltage distribution network undertakes the key function of transmitting domestic electricity at the end of the power grid. The low-voltage distribution system topology automatic identification method is used to calculate the connection relationship of various electrical equipment in the park, community, and building, and these connection relationships are stored in a certain way. Topology analysis plays a very important role in the loss calculation and energy-saving analysis of the low-voltage distribution system.

[0004] The existing smart meter network topology recognition efficiency in low-voltage power distribution is slow, and most of the smart meter networks in low-voltage power distribution use a single communication method with poor communication reliability. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a distribution network topology identification system based on HPLC and NB-IoT dual-mode communication in view of the deficiencies of the above-mentioned prior art, so as to solve the problems raised in the above-mentioned background technology.

[0006] In order to solve the above technical problems, the technical solution adopted by the present invention is: a distribution network topology identification system based on HPLC and NB-IoT dual-mode communication, including a channel selection module connected to the signal between the smart meter, and the channel selection module is respectively connected to the HPLC module and the NB-IoT module;

[0007] The HPLC module is connected to an HPLC concentrator via a power line, the HPLC concentrator is connected to a power supply master station via a GPRS / 4G network, and the power supply master station is connected to a topology identification front-end processor via a signal;

[0008] The NB-IoT module is connected to the NB-IoT cellular base station through an antenna, and then connected to the front-end processor through a signal connection between the operation platform and the topology identification front-end processor;

[0009] The topology identification front-end performs topology identification on the information, analyzes the results, and transmits the results to the power supply master station to complete the identification of the distribution network topology structure.

[0010] Preferably, the NB-IoT module is electrically connected to a rechargeable circuit and a battery.

[0011] Preferably, when there is communication between the HPLC module and the smart meter, the channel selection module prohibits the NB-IoT module from communicating with the smart meter. When the NB-IoT module is communicating with the smart meter, the HPLC module initiates communication with the smart meter, and the NB-IoT module caches the data sent by the HPLC module, and sends the data cache to the smart meter when the communication between the NB-IoT module and the smart meter is completed.

[0012] Preferably, the NB-IoT module obtains a ms-level high-precision clock from the NB-IoT network, and obtains the current collection delay value of the smart meter 1 through testing, calculation or AI, for synchronization correction and standby use.

[0013] Preferably, the current collection delay value is the delay in starting to send a current reading instruction to the smart meter 1 to collect current.

[0014] Preferably, the multiple NB-IoT modules transmit the current disturbance information to the topology identification front-end through the operation platform for topology identification, and then transmit the analysis results to the power supply main station.

[0015] Preferably, the current disturbance is specifically a sudden jump in the current at a certain point in the power line, that is, an increase or decrease;

[0016] The method for judging current disturbance is as follows: a current reading instruction is sent to the smart meter 1 at an interval of T. If the difference between the increase or decrease values ​​of two adjacent current values ​​received is greater than |ΔI|, it is considered that a current disturbance has occurred. Assuming that a current reading instruction is sent to the smart meter 1 at T0, T1, T2, .....Tn, and the difference between the current values ​​received every two times at T0, T1 or T1, T2...Tn, Tn+1 is greater than |ΔI|, a current disturbance has occurred.

[0017] Preferably, the current disturbance is divided into single-point disturbance and synchronous multi-point disturbance. Single-point disturbance refers to current disturbance occurring at the same time in two smart meters; multi-point disturbance refers to current disturbance occurring at the same time in more than two smart meters.

[0018] Preferably, the operation platform consists of a mobile operator network, a mobile operator cloud platform and a wide area network.

[0019] Compared with the prior art, the present invention has the following advantages:

[0020] The smart meter in the present invention is connected to a channel selection module, which is respectively connected to an HPLC module and an NB-IoT module. When the channel selection module communicates between the HPLC module and the smart meter, the NB-IoT module is prohibited from communicating with the smart meter. When the NB-IoT module is communicating with the smart meter, the HPLC module initiates communication with the smart meter, and the NB-IoT module caches the data sent by the HPLC module. When the communication between the NB-IoT module and the smart meter is completed, the data cache is sent to the smart meter. The HPLC module is connected to the HPLC centralized control unit through the power line. The HPLC concentrator is connected to the power supply main station through the GPRS / 4G network, and the power supply main station is connected to the topology identification front-end machine through the signal connection. The NB-IoT module is connected to the topology identification front-end machine through the operation platform. The topology identification front-end machine performs topology identification on the information, analyzes the results, and transmits the results to the power supply main station to complete the distribution network topology structure identification. The HPLC module and NB-IoT module are used to realize the distribution network topology identification, and the power outage reporting function of the smart meter can also be realized. The network clock of the NB-IoT module is used to realize independent high-precision comparison of the smart meter, which is convenient and practical. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is an exploded view of the overall structure of the present invention;

[0022] Description of reference numerals:

[0023] 1-smart meter; 2-channel selection module; 3-HPLC module; 4-HPLC concentrator; 5-NB-IoT module; 6-power supply master station; 7-operation platform; 8-topology identification front-end. DETAILED DESCRIPTION

[0024] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0025] like Figure 1 As shown, the present invention provides a technical solution: a distribution network topology identification system based on HPLC and NB-IoT dual-mode communication, including a channel selection module 2 connected to a smart meter 1 by signal, wherein the channel selection module 2 is respectively connected to an HPLC module 3 and an NB-IoT module 5;

[0026] When there is communication between the HPLC module 3 and the smart meter 1, the channel selection module 2 prohibits the NB-IoT module 5 from communicating with the smart meter 1. When the NB-IoT module 5 is communicating with the smart meter 1, the HPLC module 3 initiates communication with the smart meter 1, and the NB-IoT module 5 caches the data sent by the HPLC module 3, and sends the data cache to the smart meter 1 when the communication between the NB-IoT module 5 and the smart meter 1 is completed.

[0027] The HPLC module 3 is connected to the HPLC concentrator 4 via a power line, the HPLC concentrator 4 is connected to the power supply main station 6 via a GPRS / 4G network, and the power supply main station 6 is connected to the topology identification front-end 8 by signal;

[0028] The NB-IoT module 5 is electrically connected to a rechargeable circuit and a battery. When the detection circuit detects power outage / power-on, the NB-IoT module 5 reports the power outage / power-on to the power supply master station 6, and the battery is used to supply power during the power outage.

[0029] The NB-IoT module 5 is connected to the NB-IoT cellular base station via an antenna. The NB-IoT module 5 obtains a ms-level high-precision clock from the NB-IoT network, and obtains the current collection delay value of the smart meter 1 through testing, calculation or AI, which is used for synchronization correction and standby use. The current collection delay value is the delay for starting to send a current reading instruction to the smart meter 1 to collect current.

[0030] The NB-IoT module 5 is then connected to the topology identification front-end 8 through a signal between the operation platform 7, and the operation platform 7 is composed of a mobile operator network, a mobile operator cloud platform, and a wide area network;

[0031] The topology identification front-end 8 performs topology identification on the information, analyzes the results, and transmits the results to the power supply master station 6 to complete the identification of the distribution network topology structure.

[0032] The multiple NB-IoT modules 5 transmit the current disturbance information to the topology identification front-end 8 via the operation platform 7 for topology identification, and then transmit the analysis results to the power supply main station 6.

[0033] The current disturbance is specifically a sudden jump in current at a certain point in the power line, that is, an increase or decrease; the current disturbance is judged as follows: a current reading instruction is sent to the smart meter 1 at an interval of T, and the difference between the increase or decrease values ​​of two adjacent current values ​​received is greater than |ΔI|, then it is considered that a current disturbance has occurred. Assuming that a current reading instruction is sent to the smart meter 1 at T0, T1, T2, .....Tn, and the difference between the current values ​​received every two times at T0, T1 or T1, T2...Tn, Tn+1 is greater than |ΔI|, then a current disturbance has occurred.

[0034] The current disturbance is divided into single-point disturbance and synchronous multi-point disturbance. Single-point disturbance means that two smart meters 1 have current disturbance at the same time; multi-point disturbance means that more than two smart meters 1 have current disturbance at the same time.

[0035] In this embodiment, it is assumed that two specific smart meters 1 have current disturbance at the same time. There may be a topological relationship between them, and the two may be in the relationship of a sub-meter and a branch main meter, or a branch main meter and a main meter. These two specific smart meters are called an associated meter pair.

[0036] If two specific smart meters 1 have current disturbances at the same time more than 5 times, there must be a topological relationship between them, and the relationship between the two must be a sub-meter and a branch main meter, or a branch main meter and a main meter.

[0037] A current disturbance occurs in a specific number of smart meters 1 at the same time. There may be a topological relationship between them. They may be a branch master meter and multiple sub-meters, or a master meter and multiple branch master meters. The smart meter with the largest current value at the same time may be the branch master meter.

[0038] It is determined that multiple identical smart meters have experienced current disturbances more than 5 times at the same time. There must be a topological relationship between them. There must be a relationship between a branch master meter and multiple sub-meters, and a master meter and multiple branch master meters. The smart meter with the largest current value at the same time must be a branch master meter.

[0039] When current disturbance occurs on two specific three-phase smart meters 1 or certain multiple three-phase smart meters 1 at the same time on three phases ABC, the certainty of a topological relationship between them is higher than that between two or more single-phase smart meters.

[0040] The current values ​​of the determined multiple smart meters 1 after disturbance at the same time are zero. There may be a relationship between a branch master meter and multiple sub-meters, or a master meter and multiple branch master meters among them. These multiple smart meters 1 may be all the meters of a branch.

[0041] It is determined that the current values ​​of multiple smart meters are zero after being disturbed more than 5 times at the same time. There must be a relationship between a branch master meter and multiple sub-meters, or a master meter and multiple branch master meters. The multiple smart meters 1 must be all the meters of a certain branch.

[0042] The error in the amplitude of the current disturbance does not affect the above judgment. The large error between the amplitude of the total meter current disturbance and the sum of the amplitudes of the current disturbances of multiple sub-meters does not affect the above judgment. The topology identification front-end 8 identifies and analyzes the topology of the power network in blocks. The maximum number of each block is only the number of smart meters of all NB-IoT modules 5 that fully cover the area.

[0043] Based on the above identification, the topology structure of the low-voltage distribution network can be identified. The power disturbance is similar to the current disturbance. Using the power disturbance method, the topology structure of the medium-voltage and medium / low-voltage power grid can also be identified.

[0044] The implementation process of distribution network topology identification includes the following steps:

[0045] S1. Determine all possible smart meters in this area;

[0046] a. Determine the total table of the substations;

[0047] b. Use HPLC module 3 to determine the possible station differentiation table;

[0048] c. Use the cell ID method of NB-IoT module 5, that is, search for all cells of NB-IoT module 5 that completely cover the area and determine all possible sub-meters. The possible sub-meters of NB-IoT cells are the largest set of meters in the area, and the possible sub-meters determined by HPLC module 3 are the smallest set of meters in the area. Any meter other than the possible sub-meters of NB-IoT cells is not in the area.

[0049] S2, input the existing predicted network structure for reference by the analysis software;

[0050] S3, more accurate synchronization;

[0051] a. Perform clock synchronization on the NB-IoT module 5 of each smart meter 1, and the absolute error of the clock value of the NB-IoT module 5 of all possible smart meters 1 in this area is less than 5mS;

[0052] b. Start the "send_sample" delay test of each smart meter 1. The NB-IoT module 5 sends a current reading instruction to some smart meters 1, and the time required from sending the instruction to the meter current sampling is equivalently determined. This value is used to correct the disturbance time scale;

[0053] c. Preliminarily set the current disturbance amplitude of each smart meter 1, and the power supply master station 6 sends a command to the smart meter 1;

[0054] d. Each smart meter 1 sets the current disturbance sampling period according to the instruction of the power supply master station 6;

[0055] S4. Start current disturbance data collection and wait for the NB-IoT module 5 of each smart meter 1 to continuously report current disturbance data.

[0056] S5, follow-up analysis;

[0057] a. Perform topological structure analysis based on the above settings;

[0058] b. The sampling amplitude setting is related to the clarity of the network topology;

[0059] c. Deterministic order: opening and closing - single point large disturbance - multiple points small disturbance;

[0060] d. The meters that appear multiple times in the associated meter pairs may be branch meters or total meters;

[0061] e. Freeze the current of the possible master and slave meters of the branch. If it meets the ∑ relationship, confirm the topological branch and the total sub-meter;

[0062] f. Add points at necessary nodes where smart meters 1 are not installed;

[0063] g. Multi-point synchronous disturbance within a reasonable time is called opening and closing, and long-term disturbance of opening group but no group closing group is called cutting and modification;

[0064] h. Adjust the current disturbance amplitude or sampling period as needed;

[0065] i. For the network topology identification of the medium voltage / low voltage part, the power disturbance method can be used for identification, and artificial intelligence related algorithms can be introduced to realize the network topology structure identification.

[0066] The distribution network topology identification system based on HPLC and NB-IoT dual-mode communication in this embodiment can realize the power outage reporting function of the smart meter 1, and can also use the network clock of the NB-IoT module 5 to realize independent high-precision time comparison of the smart meter 1;

[0067] At the same time, this solution can also realize substation identification and phase sequence identification, and with the assistance of geographic information system, it can realize power outage fault area identification, etc., which is convenient and practical.

[0068] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0069] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A distribution network topology identification system based on HPLC and NB-IoT dual-mode communication, characterized in that: It comprises a channel selection module (2) connected to the smart meter (1) for signal communication, wherein the channel selection module (2) is respectively connected to the HPLC module (3) and the NB-IoT module (5); The HPLC module (3) is connected to an HPLC concentrator (4) via a power line, the HPLC concentrator (4) is connected to a power supply master station (6) via a GPRS / 4G network, and the power supply master station (6) is connected to a topology identification front-end (8) via a signal connection; The NB-IoT module (5) is connected to the NB-IoT cellular base station via an antenna, and then connected to the topology identification front-end (8) via a signal between the operation platform (7); The topology identification front-end (8) performs topology identification on the information, analyzes the results, and transmits the results to the power supply master station (6) to complete the identification of the topology structure of the distribution network; The plurality of NB-IoT modules (5) transmit the current disturbance information to a topology identification front-end (8) via an operation platform (7) for topology identification, and then transmit the analysis result to a power supply master station (6); The current disturbance is specifically a sudden jump of the current at a certain point in the power line, that is, an increase or decrease; the current disturbance is judged as follows: a current reading instruction is sent to the smart meter (1) at an interval of T, and if the increase or decrease value of the current values ​​received between two adjacent times is greater than |∆I|, it is considered that a current disturbance has occurred. Assuming that a current reading instruction is sent to the smart meter (1) at time T0, T1, T2, .....Tn, and the difference between the current values ​​received between two adjacent times at T0, T1 or T1, T2...Tn, Tn+1 is greater than |∆I|, a current disturbance has occurred; The current disturbance is divided into single-point disturbance and synchronous multi-point disturbance. Single-point disturbance means that two smart meters (1) have current disturbance at the same time; multi-point disturbance means that more than two smart meters (1) have current disturbance at the same time. The two smart meters (1) have current disturbances at the same time for more than 5 times, and there is a topological relationship between the two smart meters (1), and the relationship between the two smart meters (1) is a sub-meter and a branch master meter or a branch master meter and a master meter; The same multiple smart meters (1) have current disturbances more than 5 times at the same time. There is a topological relationship between the multiple smart meters (1). The multiple smart meters (1) are in the relationship of a branch master meter and multiple sub-meters or a master meter and multiple branch master meters. The smart meter with the largest current value at the same time is the branch master meter.

2. According to claim 1, a distribution network topology identification system based on HPLC and NB-IoT dual-mode communication is characterized in that: The NB-IoT module (5) is electrically connected to a rechargeable circuit and a battery.

3. According to claim 1, a distribution network topology identification system based on HPLC and NB-IoT dual-mode communication is characterized in that: The channel selection module (2) prohibits the NB-IoT module (5) from communicating with the smart meter (1) when there is communication between the HPLC module (3) and the smart meter (1); when the NB-IoT module (5) is communicating with the smart meter (1), the HPLC module (3) initiates communication with the smart meter (1), and the NB-IoT module (5) caches the data sent by the HPLC module (3), and sends the data cache to the smart meter (1) when the communication between the NB-IoT module (5) and the smart meter (1) is completed.

4. According to claim 1, a distribution network topology identification system based on HPLC and NB-IoT dual-mode communication is characterized in that: The NB-IoT module (5) obtains a ms-level high-precision clock from the NB-IoT network, and obtains the current acquisition delay value of the smart meter (1) through testing, calculation or AI, for synchronization correction and standby use.

5. According to claim 4, a distribution network topology identification system based on HPLC and NB-IoT dual-mode communication is characterized in that: The current collection delay value is the delay in starting to send a current reading instruction to the smart meter (1) to collect current.

6. According to claim 1, a distribution network topology identification system based on HPLC and NB-IoT dual-mode communication is characterized in that: The operation platform (7) is composed of a mobile operator network, a mobile operator cloud platform and a wide area network.

Images