A meter positioning method based on a meter clustering mechanism

Abstract

A kind of electric meter positioning method based on electric meter clustering mechanism, steps are as follows: master station issues electric meter automatic clustering command message to CCO;CCO receives and transmits electric meter automatic clustering command message to all broadband carrier communication modules in subnet;Broadband carrier communication module reports first command response message to CCO;After CCO receives first command response message, the full network topology information matrix of district is established;CCO carries out clustering to electric meter based on full network topology information matrix and the phase information reported by each broadband carrier communication module when entering network;After clustering, CCO sends second command response message to master station, reports N only electric meter equipment number in this district and the clustering result of each electric meter;After master station receives second command response message, the clustering result of electric meter is saved, and the positioning of electric meter in district is completed.The electric meter positioning method of the present application does not need new hardware investment, and can improve the overall management efficiency of electric meter.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of electric meter area data management, and particularly relates to an electric meter positioning method based on an electric meter clustering mechanism. BACKGROUND

[0002] The basic management unit of a power distribution network is an area, which refers to the power supply range of one power distribution transformer and specifically includes the area transformer and all users belonging to the area transformer. In the area of a low-voltage power distribution network, a power transmission line generally adopts a three-phase four-wire system, in which three lines represent three phases A, B and C, and the other line is a neutral line N. At present, whether in a town residential area with relatively concentrated users or in a rural area with relatively dispersed population, in order to save equipment installation space and provide physical protection for electric meters, electric meters in a local power supply area are often installed in a multi-meter electric meter cabinet, Figure 1 The figure shows a topological structure diagram of an access cabinet in an area. A multi-meter cabinet is installed with several electric meters. After the installation of the electric meters, the on-site installation personnel will record the cabinet information corresponding to the electric meters and input the information into the power grid management system, so as to facilitate the later inspection and maintenance.

[0003] As a device that bears important functions such as monitoring of key parameters of power grid operation and user power consumption measurement in a power grid, the daily management of an electric meter is very important. Each electric meter is assigned a unique device number in the entire network after entering the power grid system, which is usually represented by a group of 16 decimal digits, so that the device number of the electric meter is unified and easy to manage. At present, the management of the specific installation position of the electric meter is generally realized by recording the cabinet information of each electric meter to indirectly locate the electric meter. The on-site recording of the electric meter device number information and its installation cabinet information and the input of the power grid management system need manual operation. Due to the long data and numerous entries, the information content is often mixed with numbers, Chinese and English letters, so it is difficult to avoid some errors in the large amount of electric meter installation position information in the power grid management system, which will cause the staff to be unable to find the corresponding target electric meter on site according to the relevant information. At this time, manual on-site investigation is needed to find the specific installation position of the target electric meter, which will cost a high labor cost and time cost, especially in some old communities with unstandard wiring, the search range is large, the process is complicated, time-consuming and labor-intensive, and the efficiency is low. Moreover, the process of manually searching for the meter needs to retrieve the specific residential address of the electric meter user, and then search in the area near the address. The related process involves the use of sensitive user personal information.

[0004] To address these issues and improve the accuracy of electricity meter location, new types of meter boxes with electronic functions have emerged on the market. These boxes are equipped with positioning devices based on BeiDou or GPS technology, or with NFC electronic tags, enabling location tracking and reducing the labor costs of manual inspection. However, electricity meters are often installed indoors, and the positioning accuracy and practical application effect based on satellite signals are not good, failing to meet actual field requirements. Furthermore, these meter boxes require additional electronic equipment, resulting in significantly higher equipment costs than traditional meter boxes, hindering their widespread adoption. Summary of the Invention

[0005] The purpose of this invention is to provide a meter location method based on a meter clustering mechanism using a broadband carrier communication network, which can improve the overall management efficiency of meters without requiring new hardware investment.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] A meter location method based on a meter clustering mechanism is used to locate meters in a transformer area electricity consumption information collection network. The transformer area electricity consumption information collection network includes a master station and multiple transformer area broadband carrier communication subnets. Each broadband carrier communication subnet includes a Control Center Operator (CCO) and meters equipped with broadband carrier communication modules. The master station interacts with the CCOs of the broadband carrier communication subnets of its subordinate transformer areas, and the CCOs interact with the meters within the broadband carrier communication subnets.

[0008] S1. Automatic clustering command message from the main station to the CCO of the broadband carrier communication subnet of the transformer area;

[0009] S2. After receiving the automatic clustering command message for electricity meters, the CCO forwards the automatic clustering command message to the broadband carrier communication modules of all electricity meters in its broadband carrier communication subnet.

[0010] S3. The broadband carrier communication module that receives the meter automatic clustering command message reports a first command response message to the CCO. The first command response message contains at least the following: 1) the network short address of the broadband carrier communication module; 2) the meter device number of the meter where the broadband carrier communication module is located; 3) the direct link information.

[0011] S4. After receiving the first command response message reported by all broadband carrier communication modules in the subnet, the CCO obtains the full network topology information of the broadband carrier communication subnet in which it is located, sorts the CCO and all broadband carrier communication modules in the broadband carrier communication subnet in ascending order of short address, and establishes the full network topology information matrix of the substation area.

[0012] S5. The CCO clusters the electricity meters based on the network topology information matrix and the phase information reported by each broadband carrier communication module when it enters the network;

[0013] S6. After the clustering is completed, the CCO sends a second command response message to the master station, reporting the device numbers of N meters in the local area according to the sorting method from meter 1 to meter N, as well as the clustering results of each meter.

[0014] S7. After receiving the second command response message reported by the CCO, the master station saves the clustering results of the electricity meters and completes the location of the electricity meters in the transformer area.

[0015] In the meter location method based on the meter clustering mechanism described above, optionally, the direct link information refers to the network short addresses of all neighboring nodes that have direct links with a certain broadband carrier communication module, as well as the average received signal-to-noise ratio of the most recent Q messages sent by the other party that the broadband carrier communication module itself has received.

[0016] In the meter location method based on the meter clustering mechanism described above, optionally, the network topology information matrix is: h i,j This represents the average received signal-to-noise ratio of the Q latest messages sent by the j-th broadband carrier communication module and received by the i-th broadband carrier communication module in the broadband carrier communication subnet, where 1≤i,j≤N, and N is the number of broadband carrier communication modules in a broadband carrier communication subnet.

[0017] In the meter location method based on the meter clustering mechanism described above, optionally, the meter clustering steps in step S5 are as follows:

[0018] S5-1. Establish an N×N dimensional symmetric matrix D. Element d in symmetric matrix D i,j Used to indicate whether two meters are in the same cluster, d i,j =d j,i d i,j ∈[0,1], the value 1 indicates that the two meters are in the same cluster, and the value 0 indicates that the two meters are not in the same cluster;

[0019] Initialize the elements of the symmetric matrix D: the first element of the first row vector and the first column vector of the symmetric matrix D is set to 1, and the values ​​of all other elements are set to 0.

[0020] S5-2. Divide the remaining N-1 meters (excluding CCO) according to their phases and assign them to the A-phase meter set φ. A Phase B meter set φ B and C-phase meter set φC Then, the meters in the three sets are clustered into in-phase meters, and the A-phase meter set φ is further divided into clusters. A The steps for clustering meters of the same phase in the system are as follows: B-phase meter set φ B and C-phase meter set φ C The steps for clustering in-phase meters and the A-phase meter set φ A The steps for clustering in-phase meters are the same:

[0021] S5-2a, For the A-phase meter set φ A N in A Based on the network topology information matrix H, find the set of A-phase meters φ. A For meter combinations with bidirectional direct links between meters, the communication link quality between each meter combination is calculated, and then the combinations are sorted from largest to smallest according to the communication link quality values ​​to obtain a list of meter combinations with bidirectional direct links in phase A.

[0022] S5-2b. For the meter combination list of phase A with bidirectional direct link, the meter combination is clustered according to the link type between the meters. There are two types of link between the meters: same-phase meter link in the same box and same-phase meter link in different boxes.

[0023] For two meters in a meter group belonging to the same box and same phase meter link, a cluster is created, resulting in several clusters. If any two clusters contain the same meter, the two clusters are merged to form a new cluster, replacing the original two old clusters. If a meter and all its neighboring meters have bidirectional communication links belonging to different box and same phase meter links, that meter is created as a separate cluster.

[0024] S5-2c, Perform in-phase cluster merging; Based on the clustering results of step S5-2b, modify the values ​​of the elements at the corresponding positions of the symmetric matrix D. If the two meters are in the same cluster, change the values ​​of the elements at the corresponding positions of the symmetric matrix D from 0 to 1 according to the numbers of the two meters.

[0025] S5-3. Perform heterogeneous cluster merging; after completing the clustering and merging of in-phase meters, a cluster set is obtained, which includes clusters formed by A-phase meters, B-phase meters, and C-phase meters. Among them, K A K represents the number of clusters formed by phase A meters. B K represents the number of clusters formed by phase B meters. C This indicates the number of clusters formed by the C-phase meter. The steps for merging dissimilar clusters are as follows:

[0026] S5-3a. Calculate the values ​​of any two out-of-phase clusters Θ in the cluster set Θ. i and Θ jThe distance value λ(Θ) between i ,Θ j ):

[0027] λ(Θ i ,Θ j = max(L(x1,x2)), where x1∈Θ i The meter x2∈Θ j Where max(L(x1,x2)) represents the heterogeneous cluster Θ i and Θ j The maximum value of the bidirectional communication link quality between any two meters in the two phase clusters. If at least one meter can be found in each of the two phase clusters and there is a bidirectional direct link between these two meters, then the two phase clusters are classified as direct phase clusters. Otherwise, if no meter can be found, the two phase clusters are classified as non-direct phase clusters.

[0028] S5-3b. For each cluster Θ in the cluster set Θ k The following judgment mechanism will be implemented:

[0029]

[0030] Condition P is: Let set Ψ = {Θ} k ,Θ i ,Θ j Three distinct clusters simultaneously satisfy the following two conditions:

[0031] P1) Any two clusters in set Ψ are directly connected out-of-phase clusters;

[0032] P2) For any cluster in set Ψ, the corresponding out-of-phase cluster with the largest distance value also belongs to set Ψ.

[0033] S5-3c. After completing the decision for each cluster in the cluster set Θ, merge these clusters. If any three clusters are determined to be in the same meter box, merge these three clusters to form a new cluster and replace the original three old clusters. Then, based on the clustering result, modify the value of the corresponding element of the symmetric matrix D. If two meters are in the same cluster, change the value of the corresponding element of the symmetric matrix D from 0 to 1 according to the number of the two meters.

[0034] S5-3d. After making a decision on each cluster in the cluster set Θ, if the number of clusters with a decision result of 'pending' is 0, then the clustering of the meter is completed; if the number of clusters with a decision result of 'pending' is greater than 0, then the clusters determined to be 'pending' are added to the set. middle, Then for the cluster set Each cluster in The following judgment mechanism will be implemented:

[0035]

[0036] condition Let set Two clusters with distinct phases simultaneously satisfy the following two conditions:

[0037] )cluster and cluster For direct-access heterogeneous clusters;

[0038] )cluster The corresponding heterogeneous cluster with the largest distance value is the cluster. cluster The corresponding heterogeneous cluster with the largest distance value is the cluster.

[0039] S5-3e. Complete the cluster set. After each cluster is determined, these clusters are merged. If any two clusters are determined to be in the same meter box, these two clusters are merged to form a new cluster, which replaces the original two old clusters. Then, based on the clustering result, the value of the corresponding element of the symmetric matrix D is modified. If two meters are in the same cluster, the value of the corresponding element of the symmetric matrix D is changed from 0 to 1 according to the number of the two meters.

[0040] S5-3f. If the cluster set If the number of clusters with a decision result of 'pending' is 0, then the merging of heterogeneous clusters is complete, and the clustering process of the meter ends. If the cluster set... If the number of clusters with a judgment result of 'pending' is greater than 0, no operation is performed on these clusters, and the clustering process of the meter ends.

[0041] In the meter location method based on the meter clustering mechanism described above, optionally, in step S5-2b, the type of meter is determined by the following method:

[0042] Construct a vector θ, θ = [θ1, θ2, ..., θ W ], where θ w =L w -L w+1 w = 1, ..., W-1, where W is the number of communication links in the meter combination list of phase A with bidirectional direct links;

[0043] Starting from the first element of vector θ, search downwards one by one until the first element with a value greater than 6 is found. Let this element be the λ1-th element of vector θ.

[0044] Starting from the 11th element of vector θ, search downwards one by one until you find the first element whose value is less than θ.10 Let the element of -10 be the λ2th element of vector θ. Let λ = min(λ1, λ2-1). Then, the first λ links in the W communication links of the meter combination list with bidirectional direct links are the same-box and same-phase meter links, and the remaining links are different-box and same-phase meter links.

[0045] In the meter location method based on the meter clustering mechanism described above, optionally, the communication link quality between the meter clusters is equal to the sum of the average signal-to-noise ratio values ​​of the bidirectional links between the two meters divided by 2.

[0046] In the meter location method based on the meter clustering mechanism described above, optionally, in step S1, the master station selects the early morning period to send an automatic meter clustering command message to the CCO of the broadband carrier communication subnet of the distribution area.

[0047] As can be seen from the above technical solutions, this invention utilizes the characteristic that the localized centralized installation of electricity meters creates a topology with distinct clustering features, centered around meter boxes, within a broadband carrier communication network. This provides an automatic meter clustering mechanism for user areas using broadband carrier communication technology. The network master node collects and analyzes the network-wide topology information to cluster the meters, determining which meters are most likely installed in the same meter box, and reports the clustering results to the power grid management system. When on-site staff fail to locate meters due to errors in the meter box installation information within the power grid management system, the clustering results can assist staff in quickly re-determining the meter installation location without requiring specific meter user information. This meter location method requires no new hardware investment, effectively solves the problem of errors in meter box installation information within the management system, and improves the overall management efficiency of electricity meters. Attached Figure Description

[0048] To more clearly illustrate the embodiments of the present invention, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0049] Figure 1 This is a schematic diagram of the topology of the access meter box within the transformer area;

[0050] Figure 2 A schematic diagram of the power supply line for a three-phase four-wire distribution area;

[0051] Figure 3 This is a schematic diagram of the installation circuit for a single-phase smart meter.

[0052] Figure 4This is a schematic diagram of the working phase of a node in a broadband carrier communication network in a three-phase four-wire distribution network.

[0053] Figure 5 A schematic diagram showing the coverage area of ​​in-phase and out-of-phase power lines for broadband carrier communication signals;

[0054] Figure 6 A schematic diagram of the information exchange network structure for the electricity consumption information collection network in the transformer area;

[0055] Figure 7 This is a flowchart of the method of the present invention;

[0056] Figure 8 This is a diagram showing the link relationship between different meters in two meter boxes that are relatively close to each other.

[0057] Figure 9 This is a schematic diagram illustrating the principle of the classification algorithm for in-phase communication links.

[0058] The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings. Detailed Implementation

[0059] The present invention will now be described in detail with reference to the accompanying drawings. In the detailed description of the embodiments of the present invention, for ease of explanation, the drawings illustrating the device structure will be partially enlarged without adhering to the general scale. Furthermore, the schematic diagrams are merely examples and should not be construed as limiting the scope of protection of the present invention. It should be noted that the drawings are in a simplified form and use non-precise scales, solely for the purpose of conveniently and clearly illustrating the embodiments of the present invention. Additionally, in the description of this application, terms such as "first" and "second" are used only to distinguish descriptions and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Terms such as "positive," "negative," "bottom," "upper," and "lower" indicate orientation or positional relationships based on the orientation or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention.

[0060] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can also refer to the internal connection of two components; and they can refer to a wireless connection or a wired connection. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0061] like Figure 2As shown, in China's low-voltage distribution network, transmission lines are based on transformer substations and use a three-phase four-wire system. Three lines represent phases A, B, and C (live wires), and the other is the neutral line N (neutral wire). Three-phase power supply uses these three currents as live wires, connected to different electrical loads, and then connected to a common neutral wire. In a three-phase system, when the three phases are balanced, there is no current in the neutral wire. Based on the number of power supply lines to the user's electrical equipment, electricity meters can be classified as three-phase meters (powered by three live wires simultaneously) and single-phase meters (powered by a single live wire). Three-phase meters are mainly used for metering high-power industrial electricity consumption; their installation numbers are relatively small, and they are a key focus of routine inspections by power grid management departments, so their installation location information is generally accurate. Single-phase meters are mainly used for metering electricity consumption by ordinary residential users; their numbers are large, and their installation location information is prone to errors. To achieve balanced three-phase power load on the power supply lines, installers will connect the different meters in a meter box to the power supply lines of different phases in a relatively even manner when installing single-phase meters (e.g., Figure 3 ).

[0062] With the rapid development of technology, the methods for acquiring electricity meter reading data have evolved rapidly from early manual meter reading to remote automatic meter reading. Power line communication technology is a communication technology that uses power lines as signal transmission channels and is an important communication technology in power grid systems. Due to its advantages such as large bandwidth, high transmission rate, and strong anti-interference capability, communication equipment based on broadband power line communication technology has been widely used in electricity information collection systems. Many electricity consumption areas have already installed and used related communication equipment, such as three-phase / single-phase electricity meters with embedded broadband power line communication modules and power line carrier network coordinators (CCOs). Based on the natural correlation between broadband power line communication links and power lines, this invention further applies broadband power line communication technology to the field of electricity meter positioning.

[0063] To save on equipment hardware costs and reduce the complexity of network communication protocols, all communication modules in the electricity meter centralized reading network (transformer area electricity information collection network), including single-phase and three-phase communication modules, operate in a single physical communication channel mode. The signal transceiver of each communication module can only operate on one of the three phase lines (A, B, and C) at any given time. That is... Figure 4 As shown, only the carrier network coordinator (CCO) in the network can automatically change the working phase line at any time by switching. Other communication modules (electricity meters) can only transmit and receive signals on their corresponding electricity meter's power supply line after installation and cannot be switched.

[0064] In a broadband carrier communication network, when a communication node transmits a broadband carrier communication signal, the vast majority of the energy of the emitted electromagnetic signal is transmitted along the electric field line of its phase. The electric field line is a benign metallic conductor; although it is surrounded by an insulating layer, it can still be considered an antenna with some electromagnetic signal transmission and reception capabilities. Therefore, a small amount of electromagnetic signal energy inevitably diffuses outside the wire and radiates into the air. In some application scenarios, it may further couple into wires of different phases that are spatially close, resulting in cross-phase transmission of the carrier signal. During cross-phase transmission, the carrier signal energy experiences a significant attenuation. Therefore, there is a substantial difference in the communication coverage of the carrier communication module on in-phase lines and on out-of-phase lines. Figure 5 As shown.

[0065] Based on the centralized installation method of electricity meters in multi-meter box and the physical propagation characteristics of broadband carrier communication signals on the line, this invention proposes a method for locating electricity meters based on an automatic clustering mechanism for electricity meters in a distribution area electricity information collection network using broadband carrier communication technology. This method can accurately determine which electricity meters are installed in the same meter box, thus providing key auxiliary information to on-site personnel when the location of electricity meters is lost due to errors in the meter box installation information in the electricity meter management system. This helps them to quickly relocate the lost electricity meters, effectively reducing workload and improving the overall operation and maintenance efficiency of electricity meters.

[0066] like Figure 6 As shown, the current electricity information collection network for the distribution area includes a main station and multiple broadband carrier communication subnets for various distribution areas (broadband carrier communication subnet for distribution area 1, broadband carrier communication subnet for distribution area 2, ..., broadband carrier communication subnet for distribution area K). The main station is a management node for multiple distribution areas within a large area, possessing management authority over all power grid company equipment within its assigned area. The main station is equipped with a power grid management system, which stores meter box information based on records and inputs from on-site personnel during meter installation. The meter box information includes the association between the meter and its installation box, such as at least the meter device number and the information of the meter box it is located in (installation box information). Table 1 shows one recording format for meter box information. The meter device number is a set of 16 decimal digits used to identify the meter. The installation box information is text information composed of characters (Chinese and English letters) and numbers used to identify the identity and location of the meter box.

[0067] Table 1

[0068] Item number Electric meter equipment number Installation meter box information 1 XXXXXXXXXX XXXXXXXXXX 2 XXXXXXXXXX XXXXXXXXXX 3 XXXXXXXXXX XXXXXXXXXX … … …

[0069] The master station interacts with the Control Centers (CCOs) of the broadband carrier communication subnets under its jurisdiction via remote communication methods, including but not limited to 3G, 4G, and 5G technologies. The master station serves as the management node for multiple subnets, possessing management authority over all power grid company equipment within its assigned area. Each broadband carrier communication subnet, in addition to the CCO, includes several meters equipped with broadband carrier communication modules. The CCOs of each subnet and the meters within their respective subnets exchange information through the broadband carrier communication subnet. Besides possessing the subnet identification information of their own broadband carrier communication subnet, the CCO also possesses the phase information of each meter connected to the network within the subnet, as existing single-phase smart meters can accurately determine the phase of their power supply line through their hardware, and broadband carrier communication standards require broadband carrier communication modules to report this phase information to the CCO upon network access.

[0070] Figure 7 The flowchart of the method of the present invention is shown below. Figure 7 The method for locating electricity meters according to an embodiment of the present invention will be described below. Figure 7 As shown, the method in this embodiment includes the following steps:

[0071] S1, The main station sends an automatic clustering command message to the CCO of the broadband carrier communication subnet of the Y area.

[0072] After receiving the automatic meter clustering command message, the CCO of the broadband carrier communication subnet of S2 and Y districts forwards the automatic meter clustering command message to the broadband carrier communication modules of all meters in its broadband carrier communication subnet in a network-wide broadcast manner.

[0073] S3. Upon receiving the meter automatic clustering command message, the broadband carrier communication module reports a first command response message to the CCO. The first command response message includes the following: 1) the network short address of the broadband carrier communication module; 2) the meter device number of the meter where the broadband carrier communication module is located; 3) direct link information. The direct link information of this invention refers to the network short addresses of all neighboring nodes that have direct links with a certain broadband carrier communication module, and the average signal-to-noise ratio (in dB) of the most recent Q messages sent by the other party that the broadband carrier communication module itself receives. Q can be 10.

[0074] In practical applications, the network short address of the broadband carrier communication module can be a 12-bit data. The network short address is used by the CCO to identify the broadband carrier communication module (electricity meter) in this subnet when it enters the network. The electricity meter device number can be a 64-bit data (16 decimal numbers) used to identify the electricity meter's unique identity in the national power grid system.

[0075] After receiving the first command response message reported by all broadband carrier communication modules in the subnet, S4, CCO can obtain detailed network topology information of this broadband carrier communication subnet. Then, CCO and all broadband carrier communication modules in the broadband carrier communication subnet are sorted in ascending order of short address to establish the network topology information matrix H of the transformer area Y. The network short address of CCO is fixed to the minimum value 0. Therefore, CCO is ranked first in the network topology information matrix H, that is, CCO is the first meter.

[0076] Specifically, the entire network topology information matrix h in the whole network topology information matrix H i,j This represents the average received signal-to-noise ratio (SNR) of the Q (e.g., 10) latest messages received by the i-th broadband carrier communication module (i-th meter) from the j-th broadband carrier communication module (j-th meter) in the broadband carrier communication subnet, where 1 ≤ i, j ≤ N, where N is the number of broadband carrier communication modules in a broadband carrier communication subnet, and CCO represents three-phase meters. The values ​​of the diagonal elements in the network topology information matrix H are defaulted to the maximum value of the SNR estimation mechanism. If a broadband carrier communication module cannot correctly receive messages from the other party, i.e., there is no direct link, the values ​​are defaulted to the minimum value of the SNR estimation mechanism.

[0077] After S5 and CCO complete the collection of the entire network topology information of this subnet, they cluster the electricity meters based on the entire network topology information matrix H and the phase information reported by each broadband carrier communication module (electricity meter) when it enters the network, in order to obtain the location information of the electricity meters. The location information of the electricity meters can be used to determine which meter box the electricity meter is installed in. In this invention, a cluster refers to electricity meters in the same meter box. Clustering is the process of classifying the electricity meters that are determined to be in the same meter box.

[0078] like Figure 8 As shown, the method of the present invention clusters electricity meters based on the following theory:

[0079] (1) Within the same meter box, there is a strong direct-connection link between all meters of the same phase;

[0080] (2) Within the same meter box, there is a high probability that there will be a weak cross-phase direct link between two meters with different phases;

[0081] (3) In two meter boxes with relatively close line distances, there is a medium or weak direct link between the same phase meters;

[0082] S6. After clustering is completed, CCO sends a second command response message to the master station, reporting the device numbers of N meters in this area according to the sorting method from meter 1 to meter N, as well as the clustering results of each meter.

[0083] S7. After receiving the second command response message reported by the CCO, the master station saves the meter clustering results to the power grid management system, completing the location of the meters within the distribution area. The meter clustering results include not only the meter box information but also the meter box information corresponding to other meters that are determined to be in the same cluster (meter box) (which meters are in the same cluster can be determined from the symmetric matrix D).

[0084] When power grid workers need to locate a specific meter in transformer substation Y, they can request the target meter's location information from the power grid management system. The system will provide not only the meter box information but also the installation box information for other meters located in the same cluster (box) as the target meter. If an error occurs during on-site recording or keyboard input, causing the on-site search to fail, the system can further refer to the installation box information of other meters in the same cluster (box) as the target meter to find the correct installation box information for the target meter. This allows for rapid relocation of meters whose installation locations have been lost without using the meter's user information. Generally, although the meter box installation information stored in the power grid management system may contain errors, the proportion of erroneous entries is relatively low. The probability that all meter box installation information in the same box is completely wrong is extremely low. Therefore, even if the target meter box installation information is wrong, the relevant errors can still be made up by the information recorded by other meters in the same box, thereby effectively improving the efficiency of on-site meter retrieval.

[0085] Since broadband carrier communication technology uses power lines for signal transmission, it is susceptible to interference noise generated by various power loads. During periods of low power load in the distribution area, the number and power of the operating power loads are lower, and the interference level in the power line channel is correspondingly reduced. Therefore, in step S1, the master station can select a period of low power load, such as early morning, and send an automatic meter clustering command message to the CCO of the broadband carrier communication subnet of distribution area Y via remote communication. This helps to maintain a higher stability in the communication link quality between meters.

[0086] The meter clustering process includes clustering of in-phase meters and clustering of out-of-phase meters. Specifically, the meter clustering steps in step S5 are as follows:

[0087] S5-1. Establish an N×N dimensional symmetric matrix D. Element d in symmetric matrix D i,j Used to indicate whether two electricity meters (meter i and meter j) are in the same cluster (meter box), d i,j =dj,i d i,j ∈[0,1], the value 1 indicates that the two meters are in the same cluster (same meter box), the value 0 indicates that the two meters are not in the same cluster, and the diagonal elements in the symmetric matrix D are 1 by default;

[0088] Initialize the elements in D:

[0089] The meter corresponding to CCO (meter 1) is a three-phase smart meter, the only node in the broadband carrier communication subnet with three-phase communication capability. It is responsible for measuring the total power consumption of the entire distribution area. Therefore, it needs to be installed near the output end of the low-voltage side line of the transformer and will not be mixed with other users' meters. It is installed independently in a meter box. Therefore, by default, the meter corresponding to CCO forms a cluster containing only one point, denoted as cluster 0. The first element of the first row vector and the first column vector in the symmetric matrix D has a value of 1, and the values ​​of all other elements are 0.

[0090] S5-2. Divide the remaining N-1 meters (excluding CCO) according to their phases and assign them to the A-phase meter set φ. A Phase B meter set φ B and C-phase meter set φ C Then, the meters in the three sets are clustered into in-phase meters. The following is an example of clustering the meters in set φ of phase A. A Taking the clustering of meters of the same phase as an example, let's illustrate this with the B-phase meter set φ. B and C-phase meter set φ C The clustering process for in-phase meters is the same:

[0091] S5-2a, For the A-phase meter set φ A N in A Electricity meter, based on the entire network topology information matrix Find the set of phase A meters φ A For meter combinations with bidirectional direct links between meters, the communication link quality between each meter combination (two meters) is calculated. The combinations are then sorted from highest to lowest quality to obtain a list of meter combinations with bidirectional direct links in phase A, as shown in Table 2. Optionally, the communication link quality of a meter combination is calculated as the sum of the average signal-to-noise ratios of the bidirectional links between the two meters divided by 2. For example, the communication link quality between meter i and meter j is calculated as (h... i,j +h j,i ) / 2;

[0092] Table 2. Meter combinations for Phase A of the network with bidirectional direct links.

[0093] Link number A-phase electric meter combination Communication link quality (dB) 1 <![CDATA[(meter a1, meter a2)]]> ​ 2 <![CDATA[(meter a3, meter a4)]]> <L2> … … …

[0094] S5-2b: For the meter combination list with bidirectional direct links in phase A, the meter combinations are clustered according to the link type between the meters. There are two types of link types between the meters: Type 1: same-phase meter link in the same box; and Type 2: same-phase meter link in different boxes.

[0095] For two meters in a type 1 meter combination, a cluster is created, that is, two meters in the same box and phase meter link are created into a cluster. Several clusters are obtained. Then, the obtained clusters are merged. That is, if any two clusters contain the same meter, the two clusters are merged to form a new cluster, replacing the original two old clusters.

[0096] If a certain meter m has a bidirectional communication link with all its neighboring meters that belongs to type 2 - inter-box same-phase meter link, it means that only meter m is installed on phase A in the meter box where meter m is located, and meter m establishes a separate cluster.

[0097] Because the communication line distance between two meters in the same box and of the same phase is very short, much shorter than that between two meters in different boxes but of the same phase, the quality value of the communication link in the same box and of the same phase will be significantly greater than that of the communication link in different boxes and of the same phase. At the same time, the difference between the quality values ​​of two different communication links in the same box and of the same phase is relatively small, while the difference between the quality values ​​of two different communication links in different boxes and of the same phase may be large. Based on this, the present invention classifies the links between meters in the meter combination list into the above two link types.

[0098] S5-2c, Perform in-phase cluster merging;

[0099] After clustering the same-phase meter links within the same box and the same-phase meter links in different boxes, the same-phase clusters are merged. Based on the clustering results, the values ​​of the corresponding elements in the symmetric matrix D are modified. If two meters belong to the same cluster, the value of the corresponding element in the symmetric matrix D is changed from 0 to 1 according to the meter numbers. For example, if meter a and meter b belong to the same cluster, then element d is found in the symmetric matrix D according to the meter numbers a and b. a,b , element d a,b The value was changed from 0 to 1;

[0100] S5-3, Perform heterogeneous cluster merging;

[0101] After clustering the in-phase meters for phases A, B, and C, a cluster set Θ is obtained, consisting of clusters formed by phase A meters, phase B meters, and phase C meters. Among these, the number of clusters formed by phase A meters is K. A There are K clusters formed by B-phase meters. B There are K clusters formed by C-phase meters. C indivual, Then, the heterogeneous clusters are merged, that is, it is determined whether two heterogeneous clusters are located in the same bin. The specific steps are as follows:

[0102] S5-3a. Calculate the values ​​of any two out-of-phase clusters Θ in the cluster set Θ. i and Θ j The distance value λ(Θ) between i ,Θ j ):

[0103] λ(Θ i ,Θ j = max(L(x1,x2)), where x1∈Θ i The meter x2∈Θ j Where max(L(x1,x2)) represents the heterogeneous cluster Θ i and Θ j The maximum value of the bidirectional communication link quality between any two meters in the two phase clusters. If at least one meter can be found in each of the two phase clusters and there is a bidirectional direct link between these two meters, then the two phase clusters are classified as direct phase clusters. Otherwise, if no meter can be found, the two phase clusters are classified as non-direct phase clusters.

[0104] S5-3b. For each cluster Θ in the cluster set Θ k The following judgment mechanism will be implemented:

[0105]

[0106] Condition P is: Let set Ψ = {Θ} k ,Θ i ,Θ j Three distinct clusters simultaneously satisfy the following two conditions:

[0107] P1) Any two clusters in set Ψ are directly connected out-of-phase clusters;

[0108] P2) For any cluster in set Ψ, the corresponding out-of-phase cluster with the largest distance value also belongs to set Ψ.

[0109] There are many meter boxes in a transformer substation, and the number of meters installed and the phase distribution in different meter boxes often vary. Based on the meter installation situation in the meter boxes, the meter boxes are divided into the following three categories: ① meters are installed on all three phases; ② meters are installed on only two phases; ③ meters are installed on only one phase.

[0110] From the perspective of three-phase load balancing, if a multi-meter box contains a large number of meters, such as more than three, power grid workers will generally distribute the meters across three phases according to the meter installation guidelines. Therefore, for most distribution areas, type ① meter boxes typically occupy a higher proportion. Thus, after the meters are clustered, the number of clusters K generated on each of the three phases will be... A K B and K C The values ​​are relatively close; however, due to the significant signal energy attenuation in cross-phase broadband signal transmission, cross-phase direct links account for a low proportion of direct links and often only occur between interphase meters that are very close in space. Interphase meters located within the same meter box are obviously very close in space, making cross-phase direct links more likely. Furthermore, for a single meter, the quality of the direct link between it and an interphase meter within the same box is clearly better than the quality of the direct link between interphase meters in different boxes that are farther apart. Based on these reasons, this invention designs the aforementioned cluster decision mechanism; for cluster Θ... k In other words, if it can find a cluster in each of the other two phases, and there are direct links between these three clusters, and the out-of-phase cluster with the largest distance value for each cluster still falls into the set Ψ={Θ}. k ,Θ i ,Θ j In the context of}, considering that the quality value of a direct link between meters in the same box but with different phases that are spatially close is better than that of a direct link between meters in different boxes but with different phases that are spatially far apart, it can be basically assumed that the set Ψ={Θ k ,Θ i ,Θ j In the three phase clusters, the meters are all installed in the same meter box;

[0111] S5-3c. After completing the decision for each cluster in the cluster set Θ, these clusters can be merged. That is, if any three clusters are determined to be in the same meter box, these three clusters are merged to form a new cluster and replace the original three old clusters. Then, based on the clustering result, the value of the corresponding element of the symmetric matrix D is modified. That is, if two meters are in the same cluster, the value of the corresponding element of the symmetric matrix D is changed from 0 to 1 according to the number of the two meters.

[0112] S5-3d. After making a decision on each cluster in cluster set Θ, if the number of clusters with a decision result of 'pending' is 0, it means that the merging of heterogeneous clusters is complete, and the clustering of the meter is finished. If the number of clusters with a decision result of 'pending' is greater than 0, the clusters determined to be 'pending' will be added to the set. middle, Then for the cluster set Each cluster in The following judgment mechanism will be implemented:

[0113]

[0114] condition Let set Two clusters with distinct phases simultaneously satisfy the following two conditions:

[0115] )cluster and cluster For direct-access heterogeneous clusters;

[0116] )cluster The corresponding heterogeneous cluster with the largest distance value is the cluster. cluster The corresponding heterogeneous cluster with the largest distance value is the cluster.

[0117] S5-3e. Complete the cluster set. After each cluster is determined, cluster merging can be performed on these clusters. That is, if any two clusters are determined to be in the same meter box, these two clusters will be merged to form a new cluster and replace the original two old clusters. Then, based on the clustering result, the value of the corresponding element of the symmetric matrix D is modified. That is, if two meters are in the same cluster, the value of the corresponding element of the symmetric matrix D is changed from 0 to 1 according to the number of the two meters.

[0118] S5-3f. If the cluster set If the number of clusters with a decision result of 'pending' is 0, then the merging of heterogeneous clusters is complete, and the clustering process of the meter ends. If the cluster set... If the number of clusters with a decision result of 'pending' is greater than 0, it means that the meter box containing these clusters may only have meters for this cluster installed, without meters for the other two phases. Therefore, it is impossible to find an out-of-phase cluster to merge with it. Thus, no operation is performed on these clusters, and the meter clustering process ends.

[0119] Cluster In other words, if in a set If we find a heterogeneous cluster where both sides are each other's largest heterogeneous clusters, then we can basically conclude that the meters in these two heterogeneous clusters are installed in the same meter box, and that the meter box only contains meters for the phases of these two clusters, with no meters for the remaining phase.

[0120] Furthermore, in step S5-2b, the type of meter can be determined using the following method:

[0121] Construct a vector θ, θ = [θ1, θ2, ..., θ W ], where θ w=L w -L w+1 w = 1, ..., W-1, where W is the number of communication links in the meter combination list of phase A with bidirectional direct links;

[0122] Starting from the first element of vector θ, search downwards one by one until the first element with a value greater than 6 is found. Let this element be the λ1-th element of vector θ.

[0123] Then, starting from the 11th element of vector θ, search downwards one by one until you find the first element whose value is less than θ. 10 Let the element of -10 be the λ2th element of vector θ. Let λ = min(λ1, λ2-1). Then, in the list of W communication links of the meter combination with bidirectional direct links (Table 2), the first λ links are the same-box and same-phase meter links, and the remaining links are different-box and same-phase meter links.

[0124] Since vector L = [L1, L2, ..., L W The values ​​of the elements in the vector θ are decreasing, therefore the vector θ = [θ1, θ2, ..., θ] is... W-1 Starting from left to right, if any element's value is greater than 6 (extensive testing data from various distribution areas shows that the minimum difference in communication link quality between the two types of links is generally greater than 6dB), it indicates a significant gap. Therefore, this can be used to distinguish between links with the same phase and box and links with the same phase and box. However, considering the complexity of broadband carrier communication links in actual distribution areas, an additional condition needs to be imposed: the classification result must ensure that the difference between the 10th ranked link and the worst link in type 1 cannot exceed 10dB (the 10th ranked link is chosen to exclude links with potentially abnormally large values) to ensure the accuracy, robustness, and stability of the identification results.

[0125] To verify the accuracy of the method of this invention, with the support of Zhuhai Power Grid Company, a residential electricity distribution area in Zhuhai City was selected for performance testing. The area contains 654 meters in 62 meter boxes. The device number information of the meters installed in each meter box was correctly recorded beforehand. The test was then conducted in the early morning hours, and the algorithm provided by this invention was used for meter box clustering. The test was performed 10 times. The number of clusters and the number of meters with incorrect clustering results are shown in the table below:

[0126] Table 3. Number of clusters and number of errors in the clustering algorithm for the electricity meters in the experimental area.

[0127] 1st time 2nd time 3rd time 4th time 5th time 6th time 7th time 8th time 9th time 10th time Cluster number 62 62 61 62 62 62 62 62 63 62 Number of clustering result errors 1 1 4 2 2 3 1 4 5 2

[0128] The definition of the number of clustering errors in the test is: if two meters are not in the same meter box but are mistakenly judged to be in the same meter box; or if two meters are in the same meter box but are mistakenly judged to be not in the same meter box, then it means that there is one clustering error.

[0129] The test results show that the clustering results of this invention are highly accurate. This information can complement the meter box installation information of the power grid management system, effectively helping power grid staff solve the problem of lost location due to errors in the meter box installation information of the target meter, thereby improving the efficiency of on-site management of meter distribution areas at low cost.

[0130] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for locating electricity meters based on a meter clustering mechanism, characterized in that: This is used to locate electricity meters in the electricity consumption information collection network of a distribution area. The electricity consumption information collection network of a distribution area includes a main station and multiple broadband carrier communication subnets of distribution areas. The broadband carrier communication subnet includes a Control Center Operator (CCO) and electricity meters with broadband carrier communication modules. The main station and the CCOs of the broadband carrier communication subnets of each subordinate distribution area exchange information. The CCOs and the electricity meters in the broadband carrier communication subnets exchange information. S1. The master station sends an automatic clustering command message to the CCO of the broadband carrier communication subnet of the transformer area; S2. After receiving the automatic clustering command message for electricity meters, the CCO forwards the automatic clustering command message to the broadband carrier communication modules of all electricity meters in its broadband carrier communication subnet. S3. The broadband carrier communication module that receives the meter automatic clustering command message reports a first command response message to the CCO. The first command response message includes at least the following: 1) the network short address of the broadband carrier communication module; 2) the meter device number of the meter where the broadband carrier communication module is located; 3) direct link information, which refers to the network short addresses of all neighboring nodes that have direct links with a certain broadband carrier communication module, and the average signal-to-noise ratio of the most recent Q messages sent by the other party that the broadband carrier communication module has received. S4. After receiving the first command response message reported by all broadband carrier communication modules in the subnet, the CCO obtains the full network topology information of the broadband carrier communication subnet in which it is located, sorts the CCO and all broadband carrier communication modules in the broadband carrier communication subnet in ascending order of short address, and establishes the full network topology information matrix of the substation area. S5. The CCO clusters the electricity meters based on the network topology information matrix and the phase information reported by each broadband carrier communication module when it enters the network; S6. After the clustering is completed, the CCO sends a second command response message to the master station, reporting the device numbers of N meters in the local area according to the sorting method from meter 1 to meter N, as well as the clustering results of each meter. S7. After receiving the second command response message reported by the CCO, the master station saves the clustering results of the electricity meters and completes the location of the electricity meters in the transformer area.

2. The meter location method based on meter clustering mechanism as described in claim 1, characterized in that: The network topology information matrix is ​​as follows: h i,j This represents the average received signal-to-noise ratio of the Q latest messages sent by the j-th broadband carrier communication module and received by the i-th broadband carrier communication module in the broadband carrier communication subnet, where 1≤i,j≤N, and N is the number of broadband carrier communication modules in a broadband carrier communication subnet.

3. The meter location method based on the meter clustering mechanism as described in claim 1, characterized in that: In step S5, the steps for clustering electricity meters are as follows: S5-1. Establish an N×N dimensional symmetric matrix D. Element d in symmetric matrix D i,j Used to indicate whether two meters are in the same cluster, d i,j =d j,i d i,j ∈[0,1], the value 1 indicates that the two meters are in the same cluster, and the value 0 indicates that the two meters are not in the same cluster; Initialize the elements of the symmetric matrix D: the first element of the first row vector and the first column vector of the symmetric matrix D is set to 1, and the values ​​of all other elements are set to 0. S5-2. Divide the remaining N-1 meters (excluding CCO) according to their phases and assign them to the A-phase meter set φ. A Phase B meter set φ B and C-phase meter set φ C Then, the meters in the three sets are clustered into in-phase meters, and the A-phase meter set φ is further divided into clusters. A The steps for clustering in-phase meters and the B-phase meter set φ B C-phase meter set φ C The steps for clustering meters of the same phase are the same, and the A-phase meter set φ A The steps for clustering in-phase meters in China are as follows: S5-2a, For the A-phase meter set φ A N in A Based on the network topology information matrix H, find the set of A-phase meters φ. A For meter combinations with bidirectional direct links between meters, the communication link quality between each meter combination is calculated, and then the combinations are sorted from largest to smallest according to the communication link quality values ​​to obtain a list of meter combinations with bidirectional direct links in phase A. S5-2b. For the meter combination list of phase A with bidirectional direct link, the meter combination is clustered according to the link type between the meters. There are two types of link between the meters: same-phase meter link in the same box and same-phase meter link in different boxes. For two meters in a meter group belonging to the same box and phase meter link, a cluster is created, resulting in several clusters. If any two clusters contain the same meter, the two clusters are merged to form a new cluster, replacing the original two old clusters. If a certain electricity meter and all its neighboring electricity meters have bidirectional communication links that belong to the same phase in different boxes, then that electricity meter should be established as a separate cluster. S5-2c, Perform in-phase cluster merging; Based on the clustering results of step S5-2b, modify the values ​​of the elements at the corresponding positions of the symmetric matrix D. If the two meters are in the same cluster, change the values ​​of the elements at the corresponding positions of the symmetric matrix D from 0 to 1 according to the numbers of the two meters. S5-3, Perform heterogeneous cluster merging; After completing the clustering and merging of in-phase meters, a cluster set is obtained, which includes clusters formed by A-phase meters, B-phase meters, and C-phase meters. Among them, K A K represents the number of clusters formed by phase A meters. B K represents the number of clusters formed by phase B meters. C This indicates the number of clusters formed by the C-phase meter. The steps for merging dissimilar clusters are as follows: S5-3a. Calculate the values ​​of any two out-of-phase clusters Θ in the cluster set Θ. i and Θ j The distance value λ(Θ) between i ,Θ j ): λ(Θ i ,Θ j = max(L(x1,x2)), where x1∈Θ i The meter x2∈Θ j Where max(L(x1,x2)) represents the heterogeneous cluster Θ i and Θ j The maximum value of the bidirectional communication link quality between any two meters in the two phase clusters. If at least one meter can be found in each of the two phase clusters and there is a bidirectional direct link between these two meters, then the two phase clusters are classified as direct phase clusters. Otherwise, if no meter can be found, the two phase clusters are classified as non-direct phase clusters. S5-3b. For each cluster Θ in the cluster set Θ k The following judgment mechanism will be implemented: Condition P is: Let set Ψ = {Θ} k ,Θ i ,Θ j Three distinct clusters simultaneously satisfy the following two conditions: P1) Any two clusters in set Ψ are directly connected out-of-phase clusters; P2) For any cluster in set Ψ, the corresponding out-of-phase cluster with the largest distance value also belongs to set Ψ. S5-3c. After completing the decision for each cluster in the cluster set Θ, merge these clusters. If any three clusters are determined to be in the same meter box, merge these three clusters to form a new cluster and replace the original three old clusters. Then, based on the clustering result, modify the value of the corresponding element of the symmetric matrix D. If two meters are in the same cluster, change the value of the corresponding element of the symmetric matrix D from 0 to 1 according to the number of the two meters. S5-3d. After making a decision on each cluster in the cluster set Θ, if the number of clusters with a decision result of 'pending' is 0, then the clustering of the meter is completed; if the number of clusters with a decision result of 'pending' is greater than 0, then the clusters determined to be 'pending' are added to the set. middle, Then for the cluster set Each cluster in The following judgment mechanism will be implemented: condition Let set Two clusters with distinct phases simultaneously satisfy the following two conditions: )cluster and cluster For direct-access heterogeneous clusters; )cluster The corresponding heterogeneous cluster with the largest distance value is the cluster. cluster The corresponding heterogeneous cluster with the largest distance value is the cluster. S5-3e. Complete the cluster set. After each cluster is determined, these clusters are merged. If any two clusters are determined to be in the same meter box, these two clusters are merged to form a new cluster, which replaces the original two old clusters. Then, based on the clustering result, the value of the corresponding element of the symmetric matrix D is modified. If two meters are in the same cluster, the value of the corresponding element of the symmetric matrix D is changed from 0 to 1 according to the number of the two meters. S5-3f. If the cluster set If the number of clusters with a decision result of 'pending' is 0, then the merging of heterogeneous clusters is complete, and the clustering process of the meter ends. If the cluster set... If the number of clusters with a judgment result of 'pending' is greater than 0, no operation is performed on these clusters, and the clustering process of the meter ends.

4. The meter location method based on the meter clustering mechanism as described in claim 3, characterized in that: In step S5-2b, the type of electricity meter is determined by the following method: Construct a vector θ, θ = [θ1, θ2, ..., θ W ], where θ w =L w -L w+1 w = 1, ..., W-1, where W is the number of communication links in the meter combination list of phase A with bidirectional direct links; Starting from the first element of vector θ, search downwards one by one until the first element with a value greater than 6 is found. Let this element be the λ1-th element of vector θ. Starting from the 11th element of vector θ, search downwards one by one until you find the first element whose value is less than θ. 10 Let the element of -10 be the λ2th element of vector θ. Let λ = min(λ1, λ2-1). Then, the first λ links in the W communication links of the meter combination list with bidirectional direct links are the same-box and same-phase meter links, and the remaining links are different-box and same-phase meter links.

5. The meter location method based on the meter clustering mechanism as described in claim 3, characterized in that: The communication link quality between the meter sets is equal to the sum of the average signal-to-noise ratios of the bidirectional links between the two meters divided by 2.

6. The meter location method based on the meter clustering mechanism as described in claim 1, characterized in that: In step S1, the master station selects the early morning time period to send an automatic clustering command message to the CCO of the broadband carrier communication subnet of the distribution area.

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