A system for identifying connection relationships in distribution networks

Abstract

An embodiment of the present invention discloses a system for identifying connection relationships in a distribution network. The system may include: a transmitter and at least two identification machines, wherein the transmitter includes a first zero-crossing detection circuit, a signal modulation circuit, and an intelligent analysis module; the transmitter is connected to a point to be identified in the distribution network; each of the at least two identification machines includes a second zero-crossing detection circuit and a filtering circuit; and the at least two identification machines are respectively connected to different reference points in the distribution network. The technical solution of the embodiment of the present invention covers as many reference points in the distribution network as possible that may have a connection relationship with the point to be identified, and then identifies the connection relationship by comparing the signal peaks of the filtered signals corresponding to different reference points, thereby solving the problem of misidentification due to the crosstalk of characteristic signals in the busbar of the substation, and effectively improving the recognition accuracy.

Description

Technical Field

[0001] The embodiments of the present invention relate to the field of electric power technology, and in particular to a system for identifying connection relationships in a distribution network. Background Art

[0002] With the popularization of power grid operation detection systems, the refined management of distribution networks has received increasing attention.

[0003] Connection relationships within the distribution network, such as station-line connections, line-to-transformer connections, and household-to-transformer connections, are crucial for refined management. Misidentification of connection relationships can easily lead to inadequate power outage notifications and inappropriate line loss management. Therefore, accurate identification of connection relationships is crucial.

[0004] In the process of realizing the present invention, the inventors discovered that the prior art has the following technical problems: the recognition accuracy of the connection relationship is not high enough. Summary of the Invention

[0005] An embodiment of the present invention provides a system for identifying connection relationships in a distribution network, so as to achieve accurate identification of connection relationships in the distribution network.

[0006] According to one aspect of the present invention, a system for identifying connection relationships in a distribution network is provided, which may include: a transmitter and at least two identification machines, wherein the transmitter includes a first zero-crossing detection circuit, a signal modulation circuit, and an intelligent analysis module, the transmitter is connected to a point to be identified in the distribution network, each of the at least two identification machines includes a second zero-crossing detection circuit and a filtering circuit, and the at least two identification machines are respectively connected to different reference points in the distribution network; wherein,

[0007] A first zero-crossing detection circuit is used to detect the first moment when the power frequency voltage of the point to be identified crosses zero;

[0008] A signal modulation circuit, configured to modulate and send a characteristic signal to a point to be identified at a first moment;

[0009] For each of the at least two recognition machines, a second zero-crossing detection circuit in the recognition machine can be used to detect a second moment when the power frequency voltage of a reference point connected to the recognition machine crosses zero, and extract a voltage signal of the reference point within a target interval including the second moment;

[0010] The filter circuit in the recognition machine can be used to filter the voltage signal to obtain a filtered signal corresponding to the characteristic signal;

[0011] The intelligent analysis module can be used to obtain target points that have a connection relationship with the point to be identified among the reference points corresponding to at least two recognition machines based on the signal peaks of the filtered signals respectively sent by at least some of the at least two recognition machines.

[0012] The system for identifying connection relationships in a distribution network described in an embodiment of the present invention includes a transmitter and at least two identification machines, wherein the transmitter includes a first zero-crossing detection circuit, a signal modulation circuit, and an intelligent analysis module. The transmitter is connected to a point to be identified in the distribution network, and each of the at least two identification machines includes a second zero-crossing detection circuit and a filtering circuit. The at least two identification machines are respectively connected to different reference points in the distribution network; wherein the first zero-crossing detection circuit is used to detect a first moment when the power frequency voltage of the point to be identified crosses zero; the signal modulation circuit is used to modulate and send a characteristic signal to the point to be identified at the first moment; for each of the at least two identification machines, the second zero-crossing detection circuit in the identification machine is used to detect a second moment when the power frequency voltage of the reference point connected to the identification machine crosses zero, and extract the voltage signal of the reference point within a target interval including the second moment; the filtering circuit in the identification machine is used to filter the voltage signal to obtain a filtered signal corresponding to the characteristic signal; and the intelligent analysis module is used to obtain a target point having a connection relationship with the point to be identified among the reference points corresponding to the at least two identification machines based on the signal peak values of the filtered signals respectively sent by at least some of the at least two identification machines. The above technical solution covers as many reference points in the distribution network as possible that may have a connection relationship with the point to be identified, and then identifies the connection relationship by comparing the signal peaks of the filtered signals corresponding to different reference points. This solves the problem of misidentification due to cross-contamination of characteristic signals in the busbar of the substation, and effectively improves the recognition accuracy.

[0013] It should be understood that the content described in this section is not intended to identify the key or important features of the embodiments of the present invention, nor is it intended to limit the scope of the present invention. Other features of the present invention will become readily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0015] Figure 1 This is a structural block diagram of a system for identifying connection relationships in a distribution network provided by an embodiment of the present invention;

[0016] Figure 2a This is a schematic diagram of an applicable scenario in a system for identifying connection relationships in a distribution network provided by an embodiment of the present invention;

[0017] Figure 2bis a schematic diagram of another applicable scenario in a system for identifying connection relationships in a distribution network provided by an embodiment of the present invention;

[0018] Figure 2c This is a schematic diagram of another applicable scenario of a system for identifying connection relationships in a distribution network provided by an embodiment of the present invention;

[0019] Figure 3 This is a structural block diagram of another system for identifying connection relationships in a distribution network provided by an embodiment of the present invention;

[0020] Figure 4 This is a structural block diagram of another system for identifying connection relationships in a distribution network provided by an embodiment of the present invention;

[0021] Figure 5 This is a workflow diagram of another system for identifying connection relationships in a distribution network provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0022] In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of the present invention.

[0023] It should be noted that the terms "first", "second", etc. in the description and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. The situations of "target", "original", etc. are similar and will not be repeated here. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or that are inherent to these processes, methods, products or devices.

[0024] Figure 1 This is a block diagram of a system for identifying connection relationships in a distribution network, provided in an embodiment of the present invention. This embodiment is applicable to identifying line-to-transformer connection relationships in a distribution network, and in particular, to identifying station-to-line-to-transformer connection relationships in a distribution network. Station-to-line-to-transformer here can be understood as abbreviations for substations, power supply lines, and distribution transformers.

[0025] See also Figure 1 The identification system according to the embodiment of the present invention may include: a transmitter 10 and at least two identification machines 20 (two are used as an example here), wherein the transmitter 10 includes a first zero-crossing detection circuit 101, a signal modulation circuit 102 and an intelligent analysis module 103, the transmitter 10 is connected to a point to be identified in the distribution network, each of the at least two identification machines 20 includes a second zero-crossing detection circuit 201 and a filtering circuit 202, and the at least two identification machines 20 are respectively connected to different reference points in the distribution network; wherein,

[0026] The first zero-crossing detection circuit 101 is used to detect the first moment when the power frequency voltage of the point to be identified crosses zero;

[0027] The signal modulation circuit 102 is used to modulate and send a characteristic signal to the point to be identified at a first moment;

[0028] For each of the at least two recognition machines 20, the second zero-crossing detection circuit 201 in the recognition machine 20 is configured to detect a second moment at which the power frequency voltage of the reference point connected to the recognition machine 20 crosses zero, and extract a voltage signal of the reference point within a target interval including the second moment;

[0029] The filter circuit 202 in the recognition machine 20 is used to filter the voltage signal to obtain a filtered signal corresponding to the characteristic signal;

[0030] The intelligent analysis module 103 is used to obtain target points connected to the point to be identified among the reference points corresponding to at least two recognition machines 20 based on the signal peaks of the filtered signals respectively sent by at least some of the at least two recognition machines 20.

[0031] The distribution network can be understood as the network used to transmit electricity from the medium- and high-voltage power grid to user terminals. It consists of two parts: the medium-voltage distribution network and the low-voltage distribution network. It has functions such as distributing electricity, flexible control, and intelligent detection, and is the last level of transmission in the power system. Typically, the distribution network includes various equipment such as substations, distribution transformers, distribution lines, switchgear, distribution automation equipment, and conductors. The power supply line can be understood as the line used for power supply in the distribution network, such as distribution lines and / or conductors.

[0032] With respect to a point to be identified and at least two reference points to be identified in a power distribution network, an embodiment of the present invention anticipates determining a reference point having a connection relationship with the point to be identified from the at least two reference points.

[0033] In order to understand the above-mentioned points to be identified and reference points more vividly, here are three possible applicable scenarios of the present invention. Figure 2a-2cThe black squares in the diagram represent transmitter 10 connected to the point to be identified, while the black triangles represent identifier 20 connected to the reference point. In practical applications, identifier 20 can optionally include a through-core current transformer, which is attached to the reference point to connect identifier 20 to the reference point. Alternatively, transmitter 10 can be connected to the point to be identified using alligator clips.

[0034] Specifically, for scenario 1), see Figure 2a , a 10kV distribution transformer T1 has only one 10kV power source and its substation is known. The 10kV feeder to which this 10kV power source belongs needs to be identified. In this case, the point to be identified can be the low-voltage busbar of the 10kV distribution transformer T1, and at least two reference points can be the secondary current lines of the switchgear of all 10kV feeders in the substation to which the 10kV distribution transformer T1 belongs.

[0035] Applicable scenario 2), see Figure 2b 10kV distribution transformer T1 has only one 10kV power supply, and the 10kV feeder to which it belongs is known. It is necessary to identify the branch line to which this 10kV power supply belongs. In this case, the point to be identified is the low-voltage busbar on the 10kV distribution transformer T1, and at least two reference points are the secondary current lines of the switchgear at the headends of all branches (i.e., primary, secondary, and tertiary branches) on the 10kV feeder to which the 10kV distribution transformer T1 belongs.

[0036] Applicable scenario 3), see Figure 2c If the 10kV distribution transformer T1 has dual or multiple power sources, it is necessary to identify the 10kV feeder to which the current power source belongs. In this case, the point to be identified can be the low-voltage busbar on the 10kV distribution transformer T1, and at least two reference points can be the secondary current lines of the switchgear on the main lines of all 10kV power feeders of the 10kV distribution transformer T1.

[0037] It is understandable that, when the connection relationship is a household transformer connection relationship, the point to be identified may also be a meter busbar of a 220V / 380V electricity user.

[0038] Based on the above explanation, the following is a detailed introduction to each part of the recognition system.

[0039] The transmitter 10 may include a first zero-crossing detection circuit 101, a signal modulation circuit 102, and an intelligent analysis module 103. The first zero-crossing detection circuit 101 is configured to detect the first moment when the power frequency voltage at the point to be identified crosses zero. The first moment here can be understood as the moment when the power frequency voltage at the point to be identified crosses zero. The signal modulation circuit 102 is configured to modulate and transmit a characteristic signal to the point to be identified at the first moment. This is to implement topology verification based on the principle that the characteristic signal can be present at any location on the same power supply line. It can be seen that the embodiments of the present invention utilize the power frequency voltage of the distribution network, i.e., the 50 Hz power frequency waveform itself, as a carrier for information transmission. This eliminates the need for additional superimposition of medium-, high-, or low-frequency carrier signals as a carrier for information transmission. Specifically, the communication signal in the embodiments of the present invention can represent information through slight distortions generated near the zero-crossing point of the power frequency voltage. These slight distortions are inevitable in the 50 Hz power frequency waveform. The signal frequency is low (250 Hz to 500 Hz), and the distribution network has minimal signal attenuation, allowing the signal to be transmitted directly through the distribution transformer. This communication method can be called industrial frequency communication, which effectively utilizes the characteristics of the distribution network itself to achieve fast, efficient and low-cost communication transmission.

[0040] Each of the at least two recognition machines 20 may include a second zero-crossing detection circuit 201 and a filtering circuit 202. The second zero-crossing detection circuit 201 is configured to detect the second moment when the power frequency voltage at the reference point connected to the recognition machine 20 crosses zero, and extract the voltage signal of the reference point within a target interval containing the second moment. For example, the voltage signal may be extracted within a 30° interval around the power frequency voltage zero crossing. The filtering circuit 202 is configured to filter the voltage signal to obtain a filtered signal corresponding to the characteristic signal, i.e., the filtered signal can characterize the characteristic signal to a certain extent.

[0041] On this basis, the intelligent analysis module 103 is further configured to obtain, based on the peak values of the filtered signals transmitted by at least some of the at least two recognition machines 20, target points that are connected to the point to be recognized, among the reference points corresponding to the at least two recognition machines 20. It should be noted that, for some reasons, some of the at least two recognition machines 20 may not be able to return filtered signals. Therefore, the intelligent analysis module 103 receives filtered signals transmitted by at least some of the at least two recognition machines 20, i.e., some or all of the recognition machines 20.

[0042] It should be noted that after the characteristic signal is injected at the point to be identified, the characteristic signal can be transmitted along the power supply line to the head end, that is, the substation. Since the branch line and busbar of the substation are connected, after the characteristic signal is transmitted to the head end, it may be strung from the power supply line where it originally is located to other power supply lines, thus forming a situation where the characteristic signal is strung in the busbar of the substation.

[0043] For ease of explanation, the reference point that has a connection relationship with the point to be identified among the at least two reference points can be used as the target point, and the reference point corresponding to the same busbar as the target point can be used as the cross-contamination point, and the reference point that does not correspond to the same busbar can be used as the irrelevant point. On this basis, considering that the characteristic signal has cross-contamination in the busbar of the substation, the signal peak of the filtered signal obtained from the target point is relatively strong, the signal peak of the filtered signal obtained from the cross-contamination point is in the middle, and the signal peak of the filtered signal obtained from the irrelevant point is very weak, almost 0, and the intelligent analysis module 103 may not be able to receive the filtered signal obtained from the irrelevant point. It can be seen that by comparing the signal peaks of each filtered signal, the target point that has a connection relationship with the point to be identified among the reference points corresponding to at least two identification machines 20 can be obtained. For example, the reference point corresponding to the filtered signal with the largest signal peak among the filtered signals can be used as the target point, or the target point can be determined by combining the signal peaks of each filtered signal and the target threshold value related to the signal peak, etc., which are not specifically limited here.

[0044] The above technical solution has at least the following effects:

[0045] 1. By covering as many reference points as possible that may be connected to the point to be identified, the connection relationship is identified by comparing the peak values of the filtered signals corresponding to different reference points. This solves the problem of misidentification caused by crosstalk between characteristic signals in the substation busbar, effectively improving identification accuracy.

[0046] 2. Easy connection, simple operation, and clear logic help distribution network managers sort out records and assist in line loss analysis and judgment, which plays an important role in improving the management and operation efficiency of the distribution network.

[0047] The system for identifying connection relationships in a distribution network described in an embodiment of the present invention includes a transmitter and at least two identification machines, wherein the transmitter includes a first zero-crossing detection circuit, a signal modulation circuit, and an intelligent analysis module. The transmitter is connected to a point to be identified in the distribution network, and each of the at least two identification machines includes a second zero-crossing detection circuit and a filtering circuit. The at least two identification machines are respectively connected to different reference points in the distribution network; wherein the first zero-crossing detection circuit is used to detect a first moment when the power frequency voltage of the point to be identified crosses zero; the signal modulation circuit is used to modulate and send a characteristic signal to the point to be identified at the first moment; for each of the at least two identification machines, the second zero-crossing detection circuit in the identification machine is used to detect a second moment when the power frequency voltage of the reference point connected to the identification machine crosses zero, and extract the voltage signal of the reference point within a target interval including the second moment; the filtering circuit in the identification machine is used to filter the voltage signal to obtain a filtered signal corresponding to the characteristic signal; and the intelligent analysis module is used to obtain a target point having a connection relationship with the point to be identified among the reference points corresponding to the at least two identification machines based on the signal peak values of the filtered signals respectively sent by at least some of the at least two identification machines. The above technical solution covers as many reference points in the distribution network as possible that may have a connection relationship with the point to be identified, and then identifies the connection relationship by comparing the signal peaks of the filtered signals corresponding to different reference points. This solves the problem of misidentification due to cross-contamination of characteristic signals in the busbar of the substation, and effectively improves the recognition accuracy.

[0048] On this basis, an optional technical solution is to identify the filter circuit in the machine, which is specifically used to:

[0049] The voltage signal is filtered according to the operating frequency of the power frequency voltage and the signal frequency of the characteristic signal to obtain a filtered signal corresponding to the characteristic signal.

[0050] For example, assuming the operating frequency of the power voltage is 50 Hz and the characteristic signal has a frequency between 250 Hz and 500 Hz, the filtering circuit can filter out power frequency signals below 250 Hz and harmonics, as well as interference signals above 1 kHz, from the voltage signal, generating a filtered voltage signal corresponding to the characteristic signal. This technical solution effectively filters the voltage signal.

[0051] Continue to see Figure 1 This embodiment is optimized based on the above-mentioned technical solutions. In this embodiment, the optional intelligent analysis module can be specifically configured to: determine, based on the reference peak value of the characteristic signal and the peak value of the filtered signals transmitted by at least some of the at least two recognition machines, a target point that is connected to the point to be recognized, from the reference points corresponding to the at least two recognition machines. Explanations of terms that are identical or corresponding to the above-mentioned embodiments are not repeated here.

[0052] For details, see Figure 1 The identification system described in the embodiment of the present invention may specifically include: a transmitter 10 and at least two identification machines 20 (two are used as an example here), wherein the transmitter 10 includes a first zero-crossing detection circuit 101, a signal modulation circuit 102, and an intelligent analysis module 103, the transmitter 10 is connected to a point to be identified in the distribution network, each of the at least two identification machines 20 may include a second zero-crossing detection circuit 201 and a filtering circuit 202, and the at least two identification machines 20 are respectively connected to different reference points in the distribution network; wherein,

[0053] The first zero-crossing detection circuit 101 is used to detect the first moment when the power frequency voltage of the point to be identified crosses zero;

[0054] The signal modulation circuit 102 is used to modulate and send a characteristic signal to the point to be identified at a first moment;

[0055] For each of the at least two recognition machines 20, the second zero-crossing detection circuit 201 in the recognition machine 20 is configured to detect a second moment at which the power frequency voltage of the reference point connected to the recognition machine 20 crosses zero, and extract a voltage signal of the reference point within a target interval including the second moment;

[0056] The filter circuit 202 in the recognition machine 20 is used to filter the voltage signal to obtain a filtered signal corresponding to the characteristic signal;

[0057] The intelligent analysis module 103 is used to obtain a target point having a connection relationship with the point to be identified among the reference points corresponding to at least two recognition machines 20 based on the reference peak value of the characteristic signal and the signal peak value of the filtered signal respectively sent by at least some of the recognition machines 20 in the at least two recognition machines 20.

[0058] Among them, when the signal peaks of each filtered signal are small, this means that each filtered signal is an interference signal, and the target point identified directly based on the signal peaks of these filtered signals is incorrect. Therefore, in order to ensure the recognition accuracy, the intelligent analysis module 103 can obtain the reference peak of the characteristic signal, which is the signal peak of the characteristic signal in amperes (A), and then compare the reference peak and the signal peaks of each filtered signal together, thereby ensuring the recognition accuracy of the target point. For example, the maximum signal with the largest signal peak among the various filtered signals can be determined, and then when the absolute value of the difference between the signal peak of the maximum signal and the reference peak is less than or equal to the target threshold, that is, when the signal peak of the maximum signal is closer to the reference peak, the reference point corresponding to the maximum signal is used as the target point. Of course, these signal peaks can also be compared together in other ways, which are not specifically limited here.

[0059] The technical solution of the embodiment of the present invention further improves the recognition accuracy of the connection relationship in the distribution network by jointly comparing the reference peak value of the characteristic signal and the signal peak value of each filtered signal.

[0060] On this basis, an optional technical solution, the intelligent analysis module, is specifically used to:

[0061] For filtered signals sequentially sent by at least some of the at least two recognition machines, calculating an absolute value of a difference between a signal peak of a currently received filtered signal and a reference peak of the characteristic signal, and comparing the absolute value with a current threshold;

[0062] When the absolute value is less than the current threshold, the current threshold is updated based on the absolute value, and the filtered signal is used as the matching signal;

[0063] When a new filtered signal is received, repeatedly performing the step of calculating the absolute value of the difference between the signal peak value of the currently received filtered signal and the reference peak value of the characteristic signal;

[0064] When the calculation of the absolute value is stopped, for the reference points corresponding to the at least two recognition machines respectively, the reference point corresponding to the currently obtained matching signal among the at least two reference points is used as the target point having a connection relationship with the point to be recognized.

[0065] It can be understood that at least some of the identification machines send their own filtered signals respectively, which means that the possibility of these filtered signals being received by the transmitter at the same time is very small, that is, they are most likely received by the transmitter in sequence, so the transmitter can process these filtered signals in sequence based on the reception order.

[0066] Specifically, the absolute value of the difference between the signal peak value of the currently received filtered signal (which may be referred to as the current signal) and the reference peak value is calculated through the intelligent analysis module, and the absolute value is compared with the current threshold value. When the absolute value is less than the current threshold value, this means that the absolute value corresponding to the signal peak value of the current signal is less than the absolute value corresponding to the last received filtered signal (which may be referred to as the previous signal), that is, compared with the reference point corresponding to the previous signal, the reference point corresponding to the current signal is more likely to have a connection relationship with the point to be identified, so the current threshold value can be updated based on the absolute value corresponding to the current signal and the current signal can be used as a matching signal. When the absolute value is greater than or equal to the current threshold value, this means that compared with the reference point corresponding to the previous signal, the reference point corresponding to the current signal is less likely to have a connection relationship with the point to be identified or is equal, so there is no need to update the current threshold value and the matching signal.

[0067] On this basis, when a new filtered signal is received, that is, the current signal is updated, the above steps can be repeated until the absolute value calculation is stopped, that is, the above steps are stopped. At this time, the currently applied matching signal is the filtered signal that is closest to the signal peak and the reference peak in all filtered signals. Therefore, the reference point corresponding to the matching signal in all reference points can be used as the target point.

[0068] The above technical solution dynamically adjusts the current threshold to identify the matching signal through a differential method, thereby effectively eliminating the interference signal and achieving accurate identification of the target point.

[0069] On this basis, an optional, intelligent analysis module is also used to:

[0070] When the filtered signal is received for the first time, a countdown is started based on the target waiting time;

[0071] When the countdown ends, stop calculating the absolute value;

[0072] The target waiting time is determined according to the injection time of the characteristic signal.

[0073] The injection time can be understood as the time required to fully inject the characteristic signal into the point to be identified. Accordingly, the target waiting time can be determined based on the injection time. For example, a preset multiple of the injection time can be used as the target waiting time. The preset multiple here can be 2 or 3 times, etc. This can be set according to actual conditions and is not specifically limited here. Upon receiving the first filtered signal, the intelligent analysis module can start a countdown based on the target waiting time and stop calculating the absolute value at the end of the countdown, i.e., stop waiting for new filtered signals. This avoids infinite waiting and ensures recognition efficiency.

[0074] Alternatively, the intelligent analysis module is further configured to, upon first receiving the filtered signal, use the product of the reference peak value and a preset ratio as the current threshold. Exemplarily, the preset ratio may be 0.1, 0.2, or 0.3, etc., and may be set based on actual circumstances and is not specifically limited herein. In other words, the initial value of the current threshold is the product, and subsequent values are the calculated absolute value.

[0075] Figure 3It is a structural block diagram of another system for identifying connection relationships in a distribution network provided in an embodiment of the present invention. This embodiment is optimized based on the above-mentioned technical solutions. In this embodiment, optionally, the number of first moments is at least two, and the signal modulation circuit can be specifically used to: based on the communication address of the transmitter, at at least one target moment in at least two first moments, modulate and send a current pulse signal to the point to be identified, so that the point to be identified receives a characteristic signal, wherein the characteristic signal is characterized by the current pulse signal corresponding to at least one target moment; each of the at least two identification machines also includes a signal demodulation circuit; the signal demodulation circuit in the identification machine is used to parse the filtered signal, and when the communication address is obtained through the analysis, the filtered signal is sent to the transmitter based on the communication address through wireless communication. Among them, the explanations of the terms that are the same as or corresponding to the above-mentioned embodiments are not repeated here.

[0076] For details, see Figure 3 The identification system according to the embodiment of the present invention may specifically include: a transmitter 10 and at least two identification machines 20 (two are used as an example here), wherein the transmitter 10 includes a first zero-crossing detection circuit 101, a signal modulation circuit 102 and an intelligent analysis module 103, and the transmitter 10 is connected to a point to be identified in the distribution network;

[0077] Each of the at least two recognition machines 20 includes a second zero-crossing detection circuit 201, a filtering circuit 202, and a signal demodulation circuit 203. The at least two recognition machines 20 are respectively connected to different reference points in the power distribution network; wherein,

[0078] A first zero-crossing detection circuit 101 is used to detect a first moment of a power frequency voltage zero-crossing point at a point to be identified, wherein the number of first moments is at least two;

[0079] The signal modulation circuit 102 is configured to modulate and transmit a current pulse signal to the point to be identified at at least one target moment among the at least two first moments based on the communication address of the transmitter 10, so that the point to be identified receives a characteristic signal, wherein the characteristic signal is characterized by the current pulse signal corresponding to the at least one target moment;

[0080] For each of the at least two recognition machines 20, the second zero-crossing detection circuit 201 in the recognition machine 20 is configured to detect a second moment at which the power frequency voltage of the reference point connected to the recognition machine 20 crosses zero, and extract a voltage signal of the reference point within a target interval including the second moment;

[0081] The filter circuit 202 in the recognition machine 20 is used to filter the voltage signal to obtain a filtered signal corresponding to the characteristic signal;

[0082] The signal demodulation circuit 203 in the recognition machine 20 can be used to parse the filtered signal and, when the communication address is obtained through the parsing, send the filtered signal to the transmitter 10 based on the communication address via wireless communication;

[0083] The intelligent analysis module 103 is used to obtain target points connected to the point to be identified among the reference points corresponding to at least two recognition machines 20 based on the signal peaks of the filtered signals respectively sent by at least some of the at least two recognition machines 20.

[0084] The target time can be understood as the time at which a current pulse signal needs to be modulated and sent to the point to be identified during at least two first time periods. The signal modulation circuit 102 modulates and sends a current pulse signal to the point to be identified at at least one target time period, based on the communication address of the transmitter 10, so that the communication address is represented by all the transmitted current pulse signals. It should be noted that the characteristic signal can be understood as a general term for all pulse current signals. Therefore, after a current pulse signal is sent to the point to be identified at at least one target time period, the point to be identified can receive the characteristic signal.

[0085] Among them, pulse current signals are short-duration pulse currents, commonly used to detect the on / off status and line connection status of power supply lines. When a power supply line is out of service and waiting for operation, the distribution network voltage is zero, making it impossible to transmit information using a distorted power frequency signal. Therefore, pulse current signals are used instead. Pulse current signals are generated by connecting a pulse generator to a power line, injecting a short pulse current into the line, transmitting the information to the other end. The pulse current signal is then received by a sensor at the receiving end and processed to obtain the required information.

[0086] Then, the signal demodulation circuit 203 in the identification machine 20 parses the filtered signal output by the filtering circuit 202, and when the communication address is parsed, the filtered signal is transmitted to the transmitter 10 via wireless communication based on the communication address. As can be seen from the above, for the irrelevant point among the at least two reference points, since the power supply line where the irrelevant point is located is disconnected from the power supply line where the point to be identified is located, the voltage signal detected at the irrelevant point does not contain a characteristic signal. This means that the signal demodulation circuit 203 cannot parse the communication address from the filtered signal corresponding to such a voltage signal, and thus cannot transmit the filtered signal back to the transmitter 10 based on the communication address. Therefore, the transmitter 10 can only receive the filtered signals sent by at least some of the at least two identification machines 20.

[0087] The technical solution of the embodiment of the present invention is to send a pulse current signal to the point to be identified through the signal modulation circuit in the transmitter based on the communication address of the transmitter; further, through the signal demodulation circuit in the identification machine, the filtered signal is analyzed, and when the communication address is obtained through the analysis, the filtered signal is returned to the transmitter based on the communication address, thereby realizing the effective return of the filtered signal.

[0088] On this basis, an optional technical solution is that the unit information in the communication address can be represented based on a preset number of cycles of the power frequency voltage, and the signal modulation circuit is specifically used to:

[0089] determining at least one target time among the at least two first times based on a communication address of the transmitter and an address coding rule corresponding to a preset number of periods;

[0090] At at least one target moment, a current pulse signal is modulated and sent to the point to be identified, so that the point to be identified receives a characteristic signal.

[0091] Among them, the unit information in the communication address can be represented based on the power frequency voltage of a preset number of cycles. For example, two adjacent power frequency cycle waveforms or four adjacent power frequency cycle waveforms can be used to represent one bit of information in the communication address. Different preset number of cycles can correspond to their own address coding rules. For example, when the preset number of cycles is 2, the address coding rules are defined as follows: the first power frequency waveform contains a pulse current signal and the second power frequency waveform does not contain a pulse current signal, which represents "1"; the first power frequency waveform does not contain a pulse current signal and the second power frequency waveform contains a pulse current signal, which represents "0". At this time, the power frequency cycle T = 20ms, and it takes 40ms to transmit 1 bit of information, so the transmission rate is: 1 / 40ms = 25bit / s. As another example, when the preset number of cycles is 4, the address encoding rule is defined as follows: the 1st and 3rd power frequency waveforms contain pulse current signals and the 2nd and 4th power frequency waveforms do not contain pulse current signals, indicating "1"; the 1st and 3rd power frequency waveforms do not contain pulse current signals and the 2nd and 4th power frequency waveforms contain pulse current signals, indicating "0". At this time, the power frequency cycle T = 20ms, and it takes 80ms to transmit 1 bit of information, so the transmission rate is: 1 / 80ms = 12.5bit / s. In this example, assuming that the communication address occupies 32 bits, the injection time of the characteristic signal is 32bit / 12.5bit / s = 2.56s.

[0092] It can be seen from this that the signal modulation circuit can be used to determine at least one target moment among at least two first moments based on the communication address of the transmitter and the address coding rules corresponding to a preset number of cycles, and then a current pulse signal is sent to the point to be identified at at least one target moment, so that the characteristic signal received by the point to be identified and represented by all the current pulse signals sent can reflect the communication address.

[0093] On this basis, the signal demodulation circuit in the recognition machine is optionally used to:

[0094] The filtered signal is parsed based on the address coding rule, and when the communication address is parsed, the filtered signal is sent to the transmitter based on the communication address through wireless communication.

[0095] Among them, since the characteristic signal is obtained based on the address coding rule, when parsing the filtered signal corresponding to the characteristic signal, it can also be parsed based on the address coding rule. Combined with the above example, for example, the sequential 2 or 4 adjacent power frequency cycle waveforms can be judged as "0" or "1" to parse out the communication address, thereby realizing the effective parsing of the communication address.

[0096] Another optional technical solution is that the signal demodulation circuit in the recognition machine is also used to:

[0097] Performing analog-to-digital conversion on the filtered signal to obtain a digital signal;

[0098] The signal demodulation circuit in the recognition machine is specifically used for:

[0099] Parse the digital signal, and when the communication address is obtained, package the machine identification of the identification machine and the digital signal into signal data, and send the signal data to the transmitter based on the communication address through wireless communication;

[0100] Intelligent analysis module, specifically used for:

[0101] Based on the signal peak values of the signal data respectively sent by at least some of the at least two recognition machines, the target data in the signal data respectively sent by at least some of the recognition machines are determined, and based on the machine identification in the target data, the target points that have a connection relationship with the point to be recognized in the reference points respectively corresponding to the at least two recognition machines are obtained.

[0102] Among them, the signal demodulation circuit performs analog-to-digital (i.e., A / D) conversion on the filtered signal to obtain a processable digital signal. Then, the digital signal is parsed, and when the communication address is obtained through the parsing, the machine identification of the recognition machine and the digital signal are packaged into signal data, and the signal data is sent to the transmitter based on the communication address via wireless communication. Furthermore, the intelligent analysis module determines the target data in these signal data based on the signal peak values of each received signal data, and then the reference point corresponding to the recognition machine represented by the machine identification in the target data can be used as the target point. The above technical solution ensures the accurate determination of the target point by packaging the machine identification into the signal data.

[0103] Figure 4 This is a flow chart of another system for identifying connection relationships in a distribution network, provided in an embodiment of the present invention. This embodiment is optimized based on the above-mentioned technical solutions. Explanations of terms that are identical or corresponding to those in the above-mentioned embodiments are not repeated here.

[0104] See also Figure 4 The identification system described in the embodiment of the present invention may specifically include: a transmitter 10 and at least two identification machines 20 (two are used as an example here), wherein the transmitter 10 includes a first zero-crossing detection circuit 101, a signal modulation circuit 102, an intelligent analysis module 103, a first wireless communication module 104, and a first power supply module 105. The first zero-crossing detection circuit 101, the signal modulation circuit 102, the intelligent analysis module 103, and the first wireless communication module 104 are respectively connected to the first power supply module 105, and the transmitter 10 is connected to the point to be identified in the distribution network;

[0105] Each of the at least two identification machines 20 includes a second zero-crossing detection circuit 201, a filtering circuit 202, a signal demodulation circuit 203, a second wireless communication module 204, a second power supply module 205, and a through-core current transformer 206. The second zero-crossing detection circuit 201, the filtering circuit 202, the signal demodulation circuit 203, the second wireless communication module 204, and the through-core current transformer 206 are respectively connected to the second power supply module 205. The at least two identification machines 20 are respectively connected to different reference points in the distribution network through their respective through-core current transformers 206; wherein,

[0106] A first zero-crossing detection circuit 101 is used to detect a first moment of a power frequency voltage zero-crossing point at a point to be identified, wherein the number of first moments is at least two;

[0107] The signal modulation circuit 102 is configured to modulate and transmit a current pulse signal to the point to be identified at at least one target moment among the at least two first moments under the control of the intelligent analysis module 103, based on the communication address of the transmitter 10, so that the point to be identified receives a characteristic signal, wherein the characteristic signal can be characterized by the current pulse signal corresponding to the at least one target moment;

[0108] For each of the at least two recognition machines 20, the second zero-crossing detection circuit 201 in the recognition machine 20 is configured to detect a second moment at which the power frequency voltage of the reference point connected to the recognition machine 20 crosses zero, and extract a voltage signal of the reference point within a target interval including the second moment;

[0109] The filter circuit 202 in the recognition machine 20 is used to filter the voltage signal according to the working frequency of the power frequency voltage and the signal frequency of the characteristic signal to obtain a filtered signal corresponding to the characteristic signal;

[0110] The signal demodulation circuit 203 in the recognition machine 20 can be used to perform analog-to-digital conversion on the filtered signal to obtain a digital signal, and when the communication address is obtained by parsing the digital signal, the machine identification of the recognition machine 20 and the digital signal are packaged into signal data, and the signal data is sent to the transmitter 10 based on the communication address through the second wireless communication module 204;

[0111] The first wireless communication module 104 is configured to input the received signal data sent by at least part of the at least two recognition machines 20 into the intelligent analysis module 103;

[0112] The intelligent analysis module 103 is used to record the reference peak value of the characteristic signal, and determine the target data in the signal data sent by at least some of the recognition machines 20 based on the reference peak value and the signal peak value of each received signal data, and obtain the target point that has a connection relationship with the point to be recognized in the reference points corresponding to at least two recognition machines 20 based on the machine identification in the target data.

[0113] In order to better understand the workflow of the above recognition system, Figure 5 For example, Figure 5As shown, the transmitter 10 is connected to the point to be identified via an alligator clip line. On this basis, the first power supply module 105 is powered on to start the first zero-crossing detection circuit 101 and detect the first moment when the power frequency voltage of the point to be identified crosses zero. The intelligent analysis module 103 controls the signal modulation circuit 102 to inject a characteristic signal into the point to be identified at the first moment according to the control command. The identification machine 20 is connected to the reference point via a through-core current transformer 206. On this basis, the second power supply module 205 is powered on to start the second zero-crossing detection circuit 201, detect the second moment when the power frequency voltage of the reference point crosses zero, and extract the voltage signal of the reference point in the left and right intervals (30°) at the second moment. Then, the filtering circuit 202 and the signal demodulation circuit 203 cooperate to analyze the voltage signal and obtain signal data. Then, the signal data is transmitted back to the transmitter 10 via wireless communication. After receiving the signal data transmitted back via wireless communication, the intelligent analysis module 103 identifies the connection relationship between the point to be identified and the reference point based on the signal data.

[0114] The identification system described in the embodiment of the present invention realizes accurate identification of connection relationships in the distribution network through the cooperation of various parts.

[0115] The above specific embodiments do not limit the scope of protection of the present invention. Those skilled in the art will appreciate that various modifications, combinations, sub-combinations, and substitutions may be made based on design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention are intended to be included within the scope of protection of the present invention.

Claims

1. A system for identifying connection relationships in a distribution network, characterized in that: include: A transmitter and at least two identification machines, wherein the transmitter includes a first zero-crossing detection circuit, a signal modulation circuit, and an intelligent analysis module, the transmitter is connected to a point to be identified in a power distribution network, each of the at least two identification machines includes a second zero-crossing detection circuit and a filtering circuit, and the at least two identification machines are respectively connected to different reference points in the power distribution network; wherein, The first zero-crossing detection circuit is used to detect the first moment when the power frequency voltage of the point to be identified crosses zero; The signal modulation circuit is configured to modulate and send a characteristic signal to the point to be identified at the first moment; For each of the at least two recognition machines, a second zero-crossing detection circuit in the recognition machine is configured to detect a second moment at which the power frequency voltage of a reference point connected to the recognition machine crosses zero, and extract a voltage signal of the reference point within a target interval including the second moment; The filter circuit in the recognition machine is used to filter the voltage signal to obtain a filtered signal corresponding to the characteristic signal; The intelligent analysis module is used to obtain target points that have a connection relationship with the to-be-identified point among the reference points corresponding to the at least two recognition machines based on the signal peaks of the filtered signals respectively sent by at least some of the at least two recognition machines.

2. The system according to claim 1, wherein: The intelligent analysis module is specifically used for: According to the reference peak value of the characteristic signal and the signal peak value of the filtered signal respectively sent by at least some of the at least two recognition machines, the target point having a connection relationship with the point to be recognized among the reference points respectively corresponding to the at least two recognition machines is obtained.

3. The system according to claim 2, characterized in that The intelligent analysis module is specifically used for: For the filtered signals sequentially sent by at least some of the at least two recognition machines, calculating an absolute value of a difference between a signal peak of a currently received filtered signal and a reference peak of the characteristic signal, and comparing the absolute value with a current threshold; In a case where the absolute value is less than the current threshold, updating the current threshold based on the absolute value, and using the filtered signal as a matching signal; When a new filtered signal is received, repeatedly performing the step of calculating the absolute value of the difference between the signal peak of the currently received filtered signal and the reference peak of the characteristic signal; When the calculation of the absolute value is stopped, for the reference points respectively corresponding to the at least two recognition machines, the reference point corresponding to the currently obtained matching signal among the at least two reference points is used as a target point having a connection relationship with the point to be recognized.

4. The system according to claim 3, characterized in that The intelligent analysis module is further used to: When the filtered signal is received for the first time, a countdown is started based on the target waiting time; When the countdown ends, stop calculating the absolute value; The target waiting time is determined according to the injection time of the characteristic signal.

5. The system according to claim 3, wherein: The intelligent analysis module is further used to: When the filtered signal is received for the first time, the product of the reference peak value and the preset ratio is used as the current threshold.

6. The system according to claim 1, wherein: The number of the first moments is at least two, and the signal modulation circuit is specifically configured to: Based on the communication address of the transmitter, at at least one target moment among the at least two first moments, modulate and transmit a current pulse signal to the point to be identified, so that the point to be identified receives a characteristic signal, wherein the characteristic signal is characterized by the current pulse signal corresponding to the at least one target moment; Each of the at least two recognition machines further includes a signal demodulation circuit; The signal demodulation circuit in the identification machine is used to parse the filtered signal and, when the communication address is obtained through the parsing, send the filtered signal to the transmitter based on the communication address via wireless communication.

7. The system according to claim 6, characterized in that The unit information in the communication address is represented based on a preset number of cycles of the power frequency voltage, and the signal modulation circuit is specifically used to: determining at least one target time among the at least two first times based on the communication address of the transmitter and the address coding rule corresponding to the preset number of periods; At the at least one target moment, a current pulse signal is modulated and sent to the point to be identified, so that the point to be identified receives a characteristic signal.

8. The system according to claim 7, characterized in that The signal demodulation circuit is specifically used for: The filtered signal is parsed based on the address coding rule, and when the communication address is parsed, the filtered signal is sent to the transmitter based on the communication address via wireless communication.

9. The system according to claim 6, wherein: The signal demodulation circuit is further used for: Performing analog-to-digital conversion on the filtered signal to obtain a digital signal; The signal demodulation circuit is specifically used for: parsing the digital signal, and when the communication address is obtained through the parsing, packaging the machine identification of the identification machine and the digital signal into signal data, and sending the signal data to the transmitter based on the communication address via wireless communication; The intelligent analysis module is specifically used to: Based on the signal peak values of the signal data respectively sent by at least some of the at least two recognition machines, the target data in the signal data respectively sent by the at least some of the recognition machines are determined, and based on the machine identification in the target data, the target points that have a connection relationship with the point to be recognized in the reference points respectively corresponding to the at least two recognition machines are obtained.

10. The system according to claim 1, wherein: The filter circuit in the recognition machine is specifically used for: The voltage signal is filtered according to the operating frequency of the power frequency voltage and the signal frequency of the characteristic signal to obtain a filtered signal corresponding to the characteristic signal.

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