Multi-zone-area topology identification method based on intelligent measurement terminal

Abstract

The invention discloses a multi-transformer-area topology identification method based on an intelligent measurement terminal, and relates to the technical field of low-voltage transformer-area topology identification. Comprising the following steps: step 1, a current terminal generates a multi-area terminal list and uploads the multi-area terminal list to a master station; step 2, performing parallel topology, generating different I-type feature codes by each terminal by using an m sequence, and performing topology identification in a transformer area in parallel; step 3, serial topology: each terminal generates different II-type feature codes by using the m sequence and the address of the to-be-determined electric meter, and topology identification of the to-be-determined electric meter is carried out in sequence; and step 4, the main station sorts topology results of all the transformer areas to obtain a multi-transformer-area topology structure diagram. The invention discloses a complete scheme for carrying out topology identification on a plurality of adjacent courts, which not only can quickly and effectively obtain the topology in the courts, but also provides an effective cross-court topology combing method. The scheme is implemented only through the intelligent measurement terminal, other equipment does not need to be installed, and the cost is greatly saved.

Description

Technical Field

[0001] The present invention relates to the technical field of low-voltage substation area topology identification, and particularly to a multi-substation area topology identification method based on an intelligent measurement terminal. Background Art

[0002] The substation area topology refers to the multi-level attribution relationship among the electricity meters, meter boxes, branches and transformers within the substation area. The substation area topology relationship is widely applied in power grid business such as power grid marketing and distribution services. It is an important basis for carrying out fault diagnosis, sectional line loss calculation, anti-stealing electricity, and reactive power optimization. In the domestic power grid, especially in the low-voltage substation area, the power supply methods are complex and diverse, there are many irregular power supply situations, and with the continuous upgrade of the distribution network, the power grid lines are transformed, old or faulty electricity meters often need to be replaced, and at the same time, there are also cross-phenomena in the electricity meter files of back-to-back substation areas. All these reasons make the substation area topology relationship intricate and difficult to sort out. The unclear substation area topology relationship has caused great difficulties for the in-depth development of power grid business and the further development of power grid marketing and distribution services, and this problem urgently needs to be solved.

[0003] For the identification of the substation area topology, the most direct way is manual inspection and sorting, checking one by one, clarifying the line direction, and determining the electricity meter attribution. However, this method is time-consuming and laborious, and the inspection difficulty is very high. Some scholars have studied the big data topology identification method, by collecting data such as current, voltage, and power of the substation area, and performing data clustering processing. However, this method is limited by the data accuracy and timeliness, and the topology success rate cannot be guaranteed. Some scholars have also studied the micro-current topology identification method, but most of them are limited to the topology within the substation area and the current signal does not carry address information, and there are few efficient and fast multi-substation area topology identification solutions. Summary of the Invention

[0004] In view of the deficiencies and defects of the existing technology, the present invention provides a multi-substation area topology identification method based on an intelligent measurement terminal. Multiple adjacent substation areas realize the topology sorting within the substation area through a parallel topology method, and find the cross-substation area electricity meters through a serial topology address matching method, without the need to install other devices, and accurately and efficiently realize the multi-substation area topology identification.

[0005] The purpose of the present invention can be achieved through the following technical solutions:

[0006] Step 1: The intelligent measurement terminal reads all adjacent CCO network information through the CCO, obtains the terminal address information of multiple adjacent substation areas centered on the current substation area, and generates a multi-substation area terminal list to upload to the master station;

[0007] Step 2: The master station generates the same number of m sequences according to the number of substation areas in the multi-substation area terminal list, and sequentially sends a group of different m sequences to the intelligent measurement terminals of each substation area. Each substation area terminal uses the m sequence to generate its own type-I feature code;

[0008] Step 3: The master station sends a topology parallel mode start command to each substation intelligent measurement terminal, that is, each substation starts topology recognition simultaneously; in the topology parallel mode, each substation terminal controls the meters in its own meter file to sequentially send type I characteristic current signals and generates a meter sending record form.

[0009] Step 4: The branch monitoring module of each substation intelligent measurement terminal performs real-time type I characteristic signal recognition, and the terminal periodically reads the type I characteristic recognition records in the branch monitoring module.

[0010] Step 5: After the topology parallel mode of all substations ends, each substation intelligent measurement terminal completes the topology sorting of the substation according to the meter sending record form and the type I characteristic recognition records, and obtains a determined meter list and a pending meter list.

[0011] Step 6: The master station sends a group of identical m-sequences to each substation intelligent measurement terminal, and each substation terminal combines the m-sequence and its own pending meter list to generate a list of type II characteristic codes carrying address information.

[0012] Step 7: The master station sequentially sends a topology serial mode start command to each substation intelligent measurement terminal in order, that is, after the topology serial mode of one substation ends, the start command is sent to the next substation; in the topology serial mode, each substation terminal controls the pending meters to sequentially send the corresponding type II characteristic current signals.

[0013] Step 8: The branch monitoring module of each substation intelligent measurement terminal performs real-time type II characteristic signal recognition, and the terminal periodically reads the type II characteristic recognition records in the branch monitoring module.

[0014] Step 9: After the topology serial mode of all substations ends, the master station reads the pending meter list and the type II characteristic recognition records in each substation intelligent measurement terminal to find the true substation belonging of the pending meters.

[0015] Step 10: The multi-substation topology process ends. The master station updates the topology files of each substation according to the topology results, draws a multi-substation topology structure diagram, and classifies the pending meters that still have not found their substation belonging into the abnormal meter list for manual investigation.

[0016] Further, in step 2, the type I characteristic code generation process is as follows: The original sequence is an N-bit m-sequence. The 1'b in the N-bit m-sequence is encoded as 10'b, and the 0'b is encoded as 01'b. After encoding, a 2N-bit encoded sequence is obtained, and the sequence bit width is T milliseconds; the encoded sequence is subjected to a double power frequency period expansion, that is, the encoded sequence is grouped according to 20 milliseconds to obtain 2N*T / 20 groups of subsequences, and a group of inverted subsequences is inserted after each group of subsequences to obtain 4N*T / 20 groups of subsequences, a total of 4N-bit encoded sequence, which is the type I characteristic code.

[0017] Further, in step 2, each intelligent measurement terminal in the substation area generates different type-I feature codes using N different m-sequences, avoiding interference to the recognition end caused by the same type-I feature codes during parallel topology identification of multiple substation areas.

[0018] Further, in step 3, the electricity meter sending record table records the time period reserved by the terminal for sending type-I feature current signals to each electricity meter, including the start time and the end time.

[0019] Further, in step 4, the type-I feature recognition record includes signal recognition strength, signal recognition phase, signal recognition time, and the branch to which the signal belongs.

[0020] Further, in step 5, the intelligent measurement terminal determines the attribution of the electricity meter by matching the time period in the electricity meter sending record with the signal recognition time in the recognition record; if there is a recognition record within the sending time period of a certain electricity meter and the signal recognition strength in the recognition record is greater than a given threshold, then this electricity meter is included in the determined electricity meter list, otherwise this electricity meter is included in the pending electricity meter list.

[0021] Further, in step 6, the type-II feature code consists of two parts: a synchronization domain and an information domain. The synchronization domain is composed of the type-I feature code described in step 2 and is used to determine the starting position of subsequent information demodulation. The synchronization domains of all terminal type-II feature codes are the same. The information domain carries electricity meter address information, including 4 information segments with a total of 64 bits of information. Each information segment consists of 12 bits of electricity meter address information and 4 bits of BCH check information. The information domains of all terminal type-II feature codes are different; each information bit in the information domain consists of two sequences: positive and negative. When the information bit is 1'b, the positive sequence is in front and the negative sequence is behind. When the information bit is 0'b, the negative sequence is in front and the positive sequence is behind; the positive sequence is composed of N2 bits of fixed m-sequence, the sequence bit width is T2 milliseconds, and the negative sequence is obtained by inverting the positive sequence.

[0022] Further, in step 8, the type-II feature recognition record includes signal synchronization strength, signal recognition phase, signal address information, and the substation area to which the signal belongs.

[0023] Further, in step 9, the master station determines the attribution of the pending electricity meters by matching the pending electricity meters of each terminal with the signal address information in the type-II feature recognition record; if the address of a certain pending electricity meter is consistent with the signal address information in a recognition record and the signal synchronization strength in the recognition record is greater than a given threshold, then this pending electricity meter is included in the substation area to which the signal belongs.

[0024] Advantageous technical effects of the present invention: The present invention provides a complete solution for simultaneously performing topology recognition on multiple adjacent power distribution areas. By using a parallel topology method to sort out the topology within a power distribution area, the overall time consumption of the solution is greatly reduced. By using a serial topology address matching method to find electricity meters across power distribution areas, it is efficient and convenient. The present invention is implemented only through intelligent measurement terminals in the power distribution area without the need to install other devices, saving equipment costs. Compared with the big data method, the present invention can effectively ensure the accuracy and reliability of topology recognition. Compared with the traditional micro-current method, the present invention proposes a solution for cross-power distribution area recognition. Description of the Drawings

[0025] Figure 1 is a schematic flowchart of a multi-power distribution area topology recognition method based on intelligent measurement terminals according to the present invention.

[0026] Figure 2 is a schematic diagram of the initial topology structure of multiple power distribution areas in an embodiment of the present invention.

[0027] Figure 3 is a schematic diagram of the topology structure after the parallel operation of multiple power distribution area topologies in an embodiment of the present invention.

[0028] Figure 4 is a schematic diagram of the topology structure after the serial operation of multiple power distribution area topologies in an embodiment of the present invention.

[0029] Figure 5 is a schematic diagram of the composition of the type II feature code in an embodiment of the present invention.

[0030] Figure 2 , in 3, 4, the circle M represents the electricity meter in the current power distribution area, and the rectangle M represents the electricity meter across power distribution areas. Detailed Implementation Manner

[0031] In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and do not limit the present invention.

[0032] Embodiment

[0033] As Figure 1 shown, a multi-power distribution area topology recognition method based on intelligent measurement terminals includes the following steps in detail:

[0034] Step 1: The intelligent measurement terminal reads all adjacent CCO network information through the CCO, obtains the terminal address information of multiple adjacent power distribution areas centered on the current power distribution area, and generates a multi-power distribution area terminal list to upload to the master station. In this embodiment, the situation of the power distribution area is shown in Table 1, and the schematic diagram of the initial topology structure is as Figure 2As shown, area 1 is the current area, and the terminal in area 1 can obtain the terminal address information of the adjacent areas 2 and 3 through CCO, and generate a terminal list containing the three areas.

[0035] Table 1

[0036] Total number of electricity meters in the file Number of electricity meters in this substation area in the file Number of electricity meters across substation areas in the file Substation area 1 (current) 8 7 1 (actually belongs to substation area 2) Substation area 2 8 7 1 (actually belongs to substation area 3) Substation area 3 8 7 1 (actually belongs to substation area 1)

[0037] Step 2: The master station generates three groups of m-sequences according to the number of stations in the multi-station terminal list, and sends a different group of m-sequences to each station intelligent measurement terminal in turn. Each station terminal uses the m-sequence to generate its own type I feature code;

[0038] The process of generating the type I signature code is as follows: considering the good autocorrelation and cross-correlation characteristics of the m-sequence, the original sequence is a 1000-bit m-sequence. According to the Manchester code, 1'b in the 1000-bit sequence is encoded as 10'b, and 0'b is encoded as 01'b. After encoding, a 2000-bit coding sequence is obtained, and the sequence width is 0.4 milliseconds. In order to reduce the decoding complexity of the recognition end and improve the decoding success rate, the coding sequence is extended by a duplex frequency cycle, that is, the coding sequence is grouped according to 20 milliseconds to obtain 40 groups of subsequences. After each group of subsequences, a group of inverted subsequences is inserted to obtain 80 groups of subsequences, a total of 4000-bit coding sequences, which is the type I signature code.

[0039] Among them, the I-type signature code generated by the intelligent measurement terminal in each substation using the m-sequence is different. This is because there may be cross-area meters between adjacent substations. If the same I-type signature code is used, it will cause interference to the identification end when multiple substations are in parallel topology, and it will be impossible to determine that the signal identified by this substation must be sent by the meter in the current file of this substation.

[0040] Step 3: The master station sends a topology parallel mode start command to each substation's intelligent measuring terminal, that is, each substation starts topology identification at the same time; in topology parallel mode, each substation terminal controls the meters in the file to send Type I characteristic current signals in sequence according to its own meter file, generates a meter sending record table, and records the time period reserved by the terminal for each meter to send Type I characteristic current signals, including the start time and the end time. Usually, this time period is 15 seconds.

[0041] Step 4: The branch monitoring module of each intelligent measurement terminal in each substation performs type I characteristic signal recognition in real time, and the terminal periodically reads the type I characteristic recognition record in the branch monitoring module, including signal recognition strength, signal recognition phase, signal recognition time, and the branch to which the signal belongs; among them, there are 5 branch monitoring modules installed on the terminal. After the terminal reads the branch monitoring module recognition record, it writes the signal recognition time. In this way, the time when the meter sends the type I characteristic current signal and the signal recognition time are both from the terminal itself, and there is no need to consider the time difference between devices, and no synchronization operation is required.

[0042] Step 5: After all the substation topology parallel modes are completed, each substation intelligent measurement terminal completes the substation topology combing according to the meter sending record table and the I-type feature recognition record, and determines the meter ownership by matching the time period in the meter sending record and the signal recognition time in the recognition record; if there is an identification record within the 15-second sending time period of a certain meter, and the signal recognition strength in the identification record is greater than the given threshold, the meter is included in the confirmed meter list, otherwise the meter is included in the pending meter list. Figure 2 As shown, after the parallel mode ends, 7 meters in each of the three substations are included in the confirmed meter list, and 1 meter is included in the pending meter list.

[0043] Step 6: The master station sends a set of identical m-sequences to each intelligent measurement terminal in each area. Each terminal in the area combines the m-sequences and its own pending meter list to generate a type II feature code list carrying address information;

[0044] like Figure 5 As shown, the type II signature code consists of a synchronization domain and an information domain. The synchronization domain consists of a type I signature code and is used to determine the starting position of subsequent information demodulation. Considering the problem of identifying meters across substations, the synchronization domain of all terminal type II signature codes must be the same; the information domain carries the meter address information, including 4 information segments with a total of 64 bits of information. Each information segment consists of 12 bits of meter address information and 4 bits of BCH check information. The meter address is usually 6 bytes and will not be repeated, so the information domains of all terminal type II signature codes are different; each information bit in the information domain consists of positive and negative sequences. When the information bit is 1'b, the positive sequence is in front and the negative sequence is in the back. When the information bit is 0'b, the negative sequence is in front and the positive sequence is in the back; the positive sequence is composed of a 100-bit fixed m sequence with a sequence bit width of 0.8 milliseconds. The positive sequence is inverted to obtain a 100-bit negative sequence.

[0045] Step 7: Considering that multiple meters in the same area simultaneously sending the same type II characteristic signal in the synchronization domain will cause interference to the identification end, the master station sends a topology serial mode start command to each area intelligent measurement terminal in sequence, that is, after the topology serial mode of one area ends, the start command is sent to the next area; in the topology serial mode, each area terminal controls the pending meter to send the corresponding type II characteristic current signal in sequence;

[0046] Step 8: The branch monitoring module of each intelligent measurement terminal in each substation performs type II characteristic signal recognition in real time, and the terminal periodically reads the type II characteristic recognition record in the branch monitoring module, including signal synchronization strength, signal recognition phase, signal address information, and the substation to which the signal belongs.

[0047] Step 9: After the end of the serial mode of all substation area topologies, the master station reads the list of pending electricity meters and the type-II feature recognition records in each substation area intelligent measurement terminal, and determines the attribution of the pending electricity meters by matching the signal address information in the pending electricity meters of each terminal and the type-II feature recognition records; if the address of a pending electricity meter is consistent with the signal address information in an identification record, and the signal synchronization strength in the identification record is greater than a given threshold, then the pending electricity meter is classified into the substation area to which the signal belongs. As Figure 3 and Figure 4 shown, after the end of the serial mode, the electricity meters in the list of pending electricity meters in the three substation areas are all classified into their respective actual substation areas.

[0048] Step 10: After the multi-substation area topology process ends, as Figure 4 shown, the master station updates the topology files of each substation area according to the topology results, draws a multi-substation area topology structure diagram, and the pending electricity meters that still have not found their substation area attribution are classified into the abnormal electricity meter list for manual investigation.

[0049] In summary, the present invention provides a complete solution for simultaneously performing topology recognition on multiple adjacent substation areas. By using a parallel topology method to achieve topology sorting within the substation area, the overall solution time is greatly reduced. By using a serial topology address matching method to find electricity meters across substation areas, it is efficient and convenient; the present invention is only implemented through the substation area intelligent measurement terminal and does not require the installation of other devices, saving equipment costs; compared with the big data method, the present invention can effectively ensure the accuracy and reliability of topology recognition; compared with the traditional micro-current method, the present invention proposes a solution for cross-substation area recognition and has good practical application value.

[0050] The above embodiments are illustrative of the specific implementation manners of the present invention and not limitations thereof. Those skilled in the relevant technical fields can make various transformations and changes without departing from the spirit and scope of the present invention to obtain corresponding equivalent technical solutions. Therefore, all equivalent technical solutions should be included in the patent protection scope of the present invention.

Claims

1. A multi-substation area topology recognition method based on an intelligent measurement terminal, characterized in that It includes the following steps: Step 1: The intelligent measurement terminal reads all adjacent CCO network information through the CCO, obtains the terminal address information of multiple adjacent power distribution areas centered on the current power distribution area, and generates a multi-power distribution area terminal list to upload to the master station; Step 2: The master station generates m sequences with the same number according to the number of power distribution areas in the multi-power distribution area terminal list, and sequentially issues a group of different m sequences to the intelligent measurement terminals of each power distribution area. Each power distribution area terminal uses the m sequence to generate its own type-I feature code; Step 3: The master station issues a topology parallel mode start command to the intelligent measurement terminals of each power distribution area, that is, each power distribution area starts topology identification simultaneously; in the topology parallel mode, each power distribution area terminal controls the meters in its own meter file to sequentially send type-I characteristic current signals to generate a meter sending record table; Step 4: The branch monitoring module of each power distribution area intelligent measurement terminal performs type-I feature signal identification in real time, and the terminal periodically reads the type-I feature identification records in the branch monitoring module; Step 5: After the topology parallel mode of all power distribution areas ends, each power distribution area intelligent measurement terminal completes the topology sorting of the power distribution area according to the meter sending record table and the type-I feature identification record, and obtains a determined meter list and a pending meter list. Step 6: The master station issues a group of the same m sequences to the intelligent measurement terminals of each power distribution area. Each power distribution area terminal combines the m sequence and its own pending meter list to generate a type-II feature code list carrying address information; Step 7: The master station sequentially issues a topology serial mode start command to the intelligent measurement terminals of each power distribution area, that is, after the topology serial mode of one power distribution area ends, the start command is issued to the next power distribution area; in the topology serial mode, each power distribution area terminal controls the pending meters to sequentially send the corresponding type-II characteristic current signals; Step 8: The branch monitoring module of each power distribution area intelligent measurement terminal performs type-II feature signal identification in real time, and the terminal periodically reads the type-II feature identification records in the branch monitoring module; Step 9: After the topology serial mode of all power distribution areas ends, the master station reads the pending meter list and the type-II feature identification records in the intelligent measurement terminals of each power distribution area to find the true power distribution area attribution of the pending meters; Step 10: After the multi-power distribution area topology process ends, the master station updates the topology files of each power distribution area according to the topology results, draws a multi-power distribution area topology structure diagram, and the pending meters that still cannot find the power distribution area attribution are included in the abnormal meter list for manual investigation.

2. The multi-substation area topology recognition method based on an intelligent measurement terminal according to claim 1, characterized in that In the said Step 2, the type-I feature code generation process is as follows: the original sequence is an N-bit m sequence. The 1'b in the N-bit m sequence is encoded as 10'b, and the 0'b is encoded as 01'b. After encoding, a 2N-bit encoded sequence is obtained, and the sequence bit width is T milliseconds; the encoded sequence is expanded by a double power frequency period, that is, the encoded sequence is grouped according to 20 milliseconds to obtain 2N*T / 20 groups of subsequences. A group of inverted subsequences is inserted after each group of subsequences to obtain 4N*T / 20 groups of subsequences, a total of 4N-bit encoded sequence, which is the type-I feature code.

3. A multi-substation area topology identification method based on an intelligent measurement terminal according to claim 1, characterized in that In the said Step 2, each power distribution area intelligent measurement terminal uses different N-bit m sequences to generate different type-I feature codes to avoid interference to the identification end due to the same type-I feature code during multi-power distribution area parallel topology.

4. A multi-substation area topology recognition method based on an intelligent measurement terminal according to claim 1, characterized in that In step 3, the power meter sending record table records the time period reserved for the terminal to send the type-I characteristic current signal to each power meter, including the start time and the end time.

5. A multi-substation area topology identification method based on an intelligent measurement terminal according to claim 1, characterized in that, In step 4, the type-I characteristic recognition record includes the signal recognition intensity, the signal recognition phase, the signal recognition time, and the branch to which the signal belongs.

6. The multi-substation area topology identification method based on an intelligent measurement terminal according to claim 1, wherein In step 5, the intelligent measurement terminal determines the power meter attribution by matching the time period in the power meter sending record with the signal recognition time in the recognition record; if there is a recognition record within the sending time period of a certain power meter and the signal recognition intensity in the recognition record is greater than the given threshold, then the power meter is classified into the determined power meter list, otherwise the power meter is classified into the pending power meter list.

7. A multi-substation area topology identification method based on an intelligent measurement terminal according to claim 1, characterized in that In step 6, the type-II characteristic code consists of a synchronization domain and an information domain. The synchronization domain is composed of the type-I characteristic code described in claim 2 and is used to determine the starting position of subsequent information demodulation. The synchronization domains of all terminal type-II characteristic codes are the same. The information domain carries the power meter address information, including 4 information segments with a total of 64 bits of information. Each information segment consists of 12 bits of power meter address information and 4 bits of BCH check information, and the information domains of all terminal type-II characteristic codes are different.

8. A multi-substation area topology recognition method based on an intelligent measurement terminal according to claim 7, characterized in that, Each information bit of the information domain consists of two sequences, positive and negative. When the information bit is 1'b, the positive sequence is in front and the negative sequence is behind. When the information bit is 0'b, the negative sequence is in front and the positive sequence is behind; the positive sequence is composed of N2 bits of fixed m-sequence, the sequence bit width is T2 milliseconds, and the positive sequence is inverted to obtain the N2-bit negative sequence.

9. The multi-substation area topology identification method based on an intelligent measurement terminal according to claim 1, wherein In step 8, the type-II characteristic recognition record includes the signal synchronization intensity, the signal recognition phase, the signal address information, and the substation area to which the signal belongs.

10. A multi-substation area topology identification method based on an intelligent measurement terminal according to claim 1, characterized in that, In step 9, the master station determines the attribution of the pending power meters by matching the pending power meters of each terminal with the signal address information in the type-II characteristic recognition record; if the address of a certain pending power meter is consistent with the signal address information in a recognition record and the signal synchronization intensity in the recognition record is greater than the given threshold, then the pending power meter is classified into the substation area to which the signal belongs.

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