CN113162656A - Low-voltage distribution station area communication network applying HPLC communication sub-network - Google Patents

Abstract

The application provides a low-voltage distribution substation communication network applying an HPLC communication sub-network, which comprises a centralized control unit (1), slave nodes (2) and a communication host (3). The centralized control unit (1) receives the information of a plurality of slave nodes (2), transmits the information to the communication host (3) after buffer processing, the centralized control unit (1) and the plurality of slave nodes (2) form a communication sub-network, and the communication mode adopts HPLC. The slave node (2) receives the setting information and the control information from the centralized control unit (1) and transmits the setting information and the control information to the master switch (4) and/or the branch switches (5); the uplink channel and the downlink channel of the centralized control unit (1) are physically isolated, the centralized control unit (1) has a relay function and can also provide power to the slave node (2), and the HPLC communication sub-network also serves as a network for the centralized control unit (1) to supply power to the slave node (2).

Description

Low-voltage distribution station area communication network applying HPLC communication sub-network

Technical Field

The application relates to the technical field of power line communication, in particular to a low-voltage power distribution station communication network applying an HPLC communication sub-network, which can realize rapid networking of a low-voltage power distribution station.

Background

In recent years, the increase of basic buildings causes the topological structure of the low-voltage distribution network to have increased complexity, increased unknown degree, increased variable degree and increased medium change, and the change causes the power line as a communication medium to have larger unknown property and stronger frequency selectivity. When the electricity environment is complex, the attenuation of the carrier signal in the power line is not negligible, meanwhile, the attenuation characteristics of signals with different frequencies are different in the transmission process, and the multipath effect of signal transmission is not negligible.

The power line carrier communication has the defects of poor channel condition, complex noise characteristics and the like. With the connection and disconnection of the power load, the channel noise has a time-varying characteristic, so that the reliable communication distance of the carrier equipment in the power utilization network varies continuously, and the network quality is difficult to guarantee. The characteristics of power line carrier communication determine that the power line carrier communication works well in a high-voltage environment. When the system operation voltage is higher than 35KV, the carrier communication operation performance of the power line is very good, and the main application occasions are transmission scheduling telephones and corresponding high-voltage protection. When the system operation voltage level is lower than 380V, the power line communication quality is poor, and the main application occasions comprise power line internet access, automatic office, intelligent meter reading and the like. In an ideal situation, the access speed of the power network is relatively fast. However, the HPLC uses a bandwidth sharing technique, and if the number of nodes networked at the same time increases, the bandwidth allocated to each node decreases, and the transmission rate decreases accordingly.

In order to improve the reliability of the power line carrier communication technology, related technical personnel start to ensure the accuracy of point-to-point communication from two aspects of a physical layer and a data link layer, and the technical improvement comprises updating coding technology between channels, reducing noise of a power line and the like. This approach only guarantees that the peer-to-peer network can survive and does not indicate that the system is in high reliability operation.

Disclosure of Invention

In order to solve at least one of the above problems, the present invention provides a communication network of a low voltage distribution area using an HPLC communication sub-network, comprising at least one centralized control unit and a plurality of slave nodes, wherein a power supply of the centralized control unit is connected to a master circuit through a conductive circuit, a power supply of the slave nodes is supplied by the centralized control unit, the centralized control unit can receive information of the plurality of slave nodes, and can transmit the information to a communication host through a buffer process and a wired or wireless manner, the centralized control unit and the plurality of slave nodes form one communication sub-network, and the centralized control unit and the plurality of slave nodes communicate with each other by using an HPLC communication method. The network system has strong destruction resistance, few communication levels, simple structure and convenient networking. The communication network uses an HPLC communication sub-network to realize rapid networking of a low-voltage power distribution area, transmits information on a main circuit of the low-voltage power distribution area, and transmits communication data and power supply through a communication sub-network which is not a main circuit.

Preferably, the centralized control unit and/or the slave node transmit information such as an electric quantity or a non-electric quantity of the main circuit of the low-voltage distribution substation or parameter settings, and perform carrier communication via a circuit of one communication sub-network other than the main circuit to transmit part or all of data of the information.

In the HPLC communication sub-network, a line for communicating between the central control unit and the slave node by HPLC is also preferably a power supply line for the central control unit to supply power to the functional modules and the electronic devices on the slave node.

Preferably, the low-voltage distribution substation communication network applying the HPLC communication sub-network further includes a master switch and a branch switch, the centralized control unit and/or the slave node may obtain part or all of information on electrical quantities, fault events, state quantities and terminal temperatures of the master switch and/or the branch switch and the like on the master circuit, and an operating power supply of the centralized control unit and/or the slave node is decoupled from an operating state of the master switch and/or the branch switch.

Preferably, the electrical quantity information includes part or all of voltage, current, active power, reactive power, power factor, frequency, residual current, and harmonic.

Preferably, the fault event includes overload trip, short circuit trip, residual current protection self-checking fault and the like.

Preferably, the state quantity includes closing and opening (manual opening and electric opening).

Preferably, the slave node may receive setting information and control information from the centralized control unit and transmit the setting information and the control information to the corresponding master switch and/or branch switch.

Preferably, the setting information includes a protection threshold, an alarm threshold, a remote control switch and the like.

Preferably, an uplink channel of the centralized control unit is physically isolated from a downlink HPLC channel, the uplink channel may be connected to the communication host in a wired or wireless manner, and when the uplink channel adopts the HPLC manner, the uplink channel is connected to a power line of a low-voltage distribution substation. The physical isolation can isolate noise, so that the impedance of a communication channel is regular, the communication rate is improved, and the error rate is reduced.

Preferably, the wired or wireless mode can adopt HPLC or 4G.

Preferably, the central control unit has a relay function, and can receive and forward information of other central control units.

Preferably, the slave node is isolated from the power line.

Preferably, the centralized control unit can be arranged in at least one of the positions of the box transformer substation, the JP cabinet, the main switch or the side hanging of the main switch.

Preferably, the slave node may be disposed inside or side-hung from the master switch and/or the branch switch.

Preferably, the HPLC communication sub-network is provided with a topology identification function at an application layer thereof, and a typical low-voltage distribution area topology structure is restored by using a current matching algorithm, and the topology structure is matched with a physical topology structure of a low-voltage distribution area power line.

Preferably, the network locally realizes automatic topology identification, and provides basic support for line loss analysis and electricity stealing protection through the integration of the node of the centralized control unit 1 and the topological complete structure of the distribution room.

Preferably, the application layer is provided with a phase recognition function, and a phase relation in a typical low-voltage transformer area topological structure is restored by adopting a current phase angle matching algorithm.

Preferably, the communication network of the low-voltage distribution area using the HPLC communication sub-networks may be provided with a plurality of HPLC communication sub-networks and a number of centralized control units equal to the number of the HPLC communication sub-networks, and the centralized control units respectively correspond to the settings of the typical applications in which the respective HPLC communication sub-networks are installed. Typical application scenarios are box-type substation, JP cabinet, low-voltage switch cabinet, batch meter, etc.

Preferably, the centralized control unit receives information of each slave node, performs non-transient protection and/or monitoring alarm calculation according to corresponding switch device classification, and sends out corresponding control command and/or fault event record.

Preferably, the non-transient protection includes overvoltage and undervoltage protection and disconnection protection.

Preferably, the monitoring content comprises residual current monitoring, automatic tracking and threshold value setting, overrun alarming, terminal temperature monitoring and overtemperature alarming.

Preferably, the communication host allocates levels to the centralized control units 1 of the sub-networks according to corresponding sequences, the sub-networks of each level are interconnected through the centralized control units 1, the slave nodes in the star network are all responsible for the centralized control units 1 of the network, and the communication host only needs to be responsible for effective communication with the centralized control units 1 and data acquisition and monitoring, so that the data acquisition efficiency of the communication host in the transformer area is improved to a certain extent, and the number of monitored nodes is greatly reduced. During data transmission, all levels of subnets work well and orderly, the lower level subnets transmit data to the centralized control unit of the upper level subnets, and simultaneously transmit data broadcast to the lower level subnets, so that the data collision rate is reduced.

Preferably, in the communication network of the low-voltage distribution area using the HPLC communication sub-network, the central control unit may further supply power to the slave nodes through the HPLC communication sub-network, so that the working power supplies of the central control unit and the slave nodes are decoupled from the working power supply of the internal control circuit of the master switch and/or the fractional switch. The centralized control unit and the slave nodes in the low-voltage distribution transformer area communication network are online in real time, and a communication host can conveniently access in real time to obtain the state of the main circuit.

The invention has the following beneficial effects:

the invention provides a low-voltage distribution substation communication network applying an HPLC communication sub-network. The centralized control unit receives the information of a plurality of slave nodes, transmits the information to the communication host after buffer processing, forms a communication sub-network with the plurality of slave nodes, and adopts an HPLC (high performance liquid chromatography) communication mode. The low-voltage distribution station area communication network can also be provided with more than one HPLC communication sub-network and centralized control units with the same number as the HPLC communication sub-networks, and the centralized control units respectively correspond to the settings of typical applications where the centralized control units are installed. The low-voltage distribution transformer area communication network is strong in destruction resistance, few in communication level, simple in structure and convenient to network. The communication network is formed by a plurality of sub-networks, and each sub-network internally comprises a centralized control unit and a slave node. Within a sub-network, the slave nodes send information such as electrical quantities, fault events, state quantities, terminal temperatures, etc. to the central control unit. The centralized control unit integrates the information at the slave nodes and sends the information to the communication host. The communication network has strong survivability, and if a certain slave node has a problem, the normal operation of the whole communication network cannot be influenced. The centralized control unit in the low-voltage distribution station communication network has a relay function. When the low-voltage distribution network is used as a power communication medium, the power of the signal determines the maximum distance that the communication network can transmit. However, if the power of the enhanced signal is increased without limitation to increase the distance of signal transmission, it will cause very strong interference to the surrounding environment. After receiving the signal, the centralized control unit firstly amplifies the signal, and when the signal reaches a certain intensity, the signal is transmitted to other centralized control units or a communication host. The method greatly improves the transmission distance of the signal, and simultaneously avoids the influence of the enhanced signal power on the surrounding environment. Meanwhile, the centralized control unit can also play a role of a gateway or a router, namely, a certain centralized control unit and a corresponding slave node form a sub-network and are communicated with other sub-networks through the centralized control unit. It is noted here that subnets may interfere with each other, requiring a wider spectrum to be used to separate the entire network.

In the low-voltage distribution transformer area communication network, the HPLC communication sub-network can realize the power supply of the centralized control unit to the slave node besides performing data communication such as main circuit information acquisition, control instruction issuing and the like, the communication circuit of the HPLC communication sub-network is also a power supply line, the defect that a communication signal line and a power supply line need to be separately arranged in other communication modes is avoided, the power supply problem of the centralized control unit and the slave node is also conveniently solved, and the defects that a working power supply is unstable and the main circuit state cannot be accessed in real time due to the fact that the centralized control unit and/or the slave node need to be accessed into the working power supply from a main switch and/or a branch switch are avoided. Therefore, the access success rate of the communication host to the communication network of the low-voltage distribution station area can be greatly improved. In addition, the centralized control unit can supply power to the slave nodes in a centralized manner, so that the cost increase caused by the fact that the slave nodes are provided with power supply devices independently is avoided, the cost for laying power supplies or communication cables is reduced due to the fact that the power supply circuit and the communication circuit are combined, the cost for modifying or building a low-voltage distribution area communication network is reduced, and the economic efficiency of modifying or building the low-voltage distribution area communication network applying the HPLC communication sub-network is obviously improved. According to the measurement and calculation, the low-voltage distribution area communication network is reconstructed or newly built by applying an HPLC communication sub-network and distributed according to the low-voltage branch cabinet standard of the low-voltage distribution area, 32 power modules and 300 meters of monitoring power lines can be saved, and the total cost is saved by about 1900 Yuan. The national power grid and the southern power grid adopt a ubiquitous Internet of things strategy, the two power grids are about more than 1000 ten thousand transformer areas, and the application of the technology can bring more than 200 million yuan investment saving for the two power grids.

In addition, the working power supply of the centralized control power supply and the slave node is decoupled with the main switch and/or the branch switch, so that the application scene requirements of the main switch and/or the branch switch are simplified, the output of a communication power supply can be cancelled for the main switch and/or the branch switch, the cost benefits of reducing the structure space, materials, components and the like are brought, the design and development difficulty is reduced, and the economic benefit of the low-voltage power distribution station area communication network applying the HPLC communication sub-network can be brought.

The low-voltage distribution transformer area communication network adopts a networking model based on the combination of the ant colony algorithm and the clustering algorithm, so that the communication network is more stable and stronger in survivability. The ant colony algorithm has the advantages of strong self-organization and robustness, and has the disadvantages of long execution time and low calculation efficiency when the number of network nodes is large. The clustering algorithm has the defects of poor dynamic performance and weak survivability. In the clustering algorithm, the nodes in each cluster member are connected with the center through a single thread. And when the networking is finished, the corresponding clustering topological structure is correspondingly determined. When communication interference prevents the data processing center from communicating with some of the nodes, the communication system must be re-networked. The invention combines the two algorithms and exerts the advantages of the two algorithms. A classification concept is added into a communication network, and the network is divided in distance by considering the limited transmission distance of a power line communication network. Namely, a plurality of sub-networks from the distribution box to a remote place appear on the low-voltage distribution line, and the hierarchical concept is adopted for the sub-networks step by step, so that the whole network can form an ordered and normalized operation mechanism. Networking is realized between each satellite contact unit and the communication host by mainly relying on an ant colony algorithm, and networking is realized by mainly relying on a clustering algorithm in a subnet formed by the centralized control unit and the slave nodes.

The low-voltage distribution transformer area communication network can realize the functions of residual current detection, automatic topology identification, line loss analysis, electricity stealing protection and the like. The slave nodes may obtain some or all of the electrical quantities, fault events, state quantities, terminal temperature information of the master and branch switches. The centralized control unit receives the information of each slave node, calculates the non-transient protection and/or monitoring alarm according to the corresponding switch device classification, and sends out a corresponding control command and/or fault event record. The electric quantity information which can be obtained from the node comprises part or all of voltage, current, active power, reactive power, power factor, frequency, residual current and harmonic; the fault event information comprises overload tripping, short-circuit tripping and residual current protection self-checking faults; the state quantity comprises closing and opening (manual opening and electric opening) states. The slave node can also receive setting information and control information from the centralized control unit and transmit the setting information and the control information to the master switch and/or the branch switches. The setting information of the centralized control unit comprises a protection threshold, an alarm threshold and a remote control on-off brake.

The low-voltage distribution station area communication network can realize N-line disconnection protection. When an N-wire is broken in a power distribution system, a neutral point is shifted, and thus, voltages of two sections of a load are increased or reduced. When the voltage at the two ends of the load is increased, the electric appliance can be burnt out, and electric shock accidents can be seriously caused. When the voltage of two sections of the load is reduced, the electric appliance can not work normally. The solution of the invention is that a current collector is arranged on an N line of a power distribution system and is used for detecting the current value flowing on the N line. If the current value on the N line is detected to be not zero, the N line can be judged to be not broken; if the current value on the N line is detected to be equal to zero, the N line is disconnected or unloaded or A, B, C is in a complete balance condition of the three-phase circuit. At this time, it is necessary to comprehensively determine the A, B, C three-phase current value and the current value on the N line. In addition to the N-line disconnection protection method described above, the N-disconnection protection can also be determined according to a threshold value of the phase angle difference.

The uplink channel and the downlink channel of the centralized control unit in the low-voltage distribution transformer area communication network are physically isolated. The design can isolate the noise between the uplink channel and the downlink channel, so that the impedance of the communication channel is regular, the communication rate is improved, and the error rate is reduced. Isolation between the slave node and the power line. The centralized control unit and the slave nodes are flexible in position. The centralized control unit can be arranged in the box transformer substation, or in the JP cabinet, or in/on the side of the main switch; the slave nodes may be placed in the master switch internal/side-hang, and/or the branch switch internal/side-hang.

The application layer of the low-voltage distribution area communication network is provided with a topology identification function, a typical low-voltage area topology structure is restored by adopting a current matching algorithm, and the topology structure is matched with a physical topology structure of a low-voltage area power line. The process can realize local automatic topology identification, and provides basic support for line loss analysis and electricity stealing protection through the integration of the node of the centralized control unit 1 and the topological complete structure of the distribution room. The application layer of the low-voltage distribution station area communication network is provided with a phase recognition function, and a phase relation in a typical low-voltage station area topological structure is restored by adopting a current phase angle matching algorithm.

The communication network hierarchy of the low-voltage power distribution station is simple in arrangement, convenient in data acquisition and higher in data transmission efficiency. The communication network can be provided with more than one HPLC communication sub-network and centralized control units with the same number as the HPLC communication sub-networks, wherein the centralized control units respectively correspond to the settings of the typical applications where the centralized control units are respectively installed. The communication host distributes the levels to the centralized control units of the sub-networks according to the corresponding sequence, all the sub-networks are mutually connected through the centralized control units, the slave nodes in the star network are all responsible for the centralized control units of the network, and the communication host only needs to be responsible for effective communication with all the centralized control units 1 and data acquisition and monitoring, so that the data acquisition efficiency of the communication host in the transformer area is improved to a certain extent, and the number of the monitored nodes is greatly reduced. During data transmission, all levels of subnets work well and orderly, the lower level subnets transmit data to the centralized control unit of the upper level subnets, and simultaneously transmit data broadcast to the lower level subnets, so that the data collision rate is reduced.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

Fig. 1 is a schematic structural diagram of a low-voltage distribution substation communication network according to a first embodiment of the present invention.

Fig. 2 is a schematic structural diagram of a low-voltage distribution substation communication network according to a second embodiment of the present invention.

Fig. 3 is a schematic structural diagram of a third embodiment of the low-voltage distribution substation communication network according to the present invention.

Fig. 4 is a schematic structural diagram of a fourth embodiment of the low-voltage distribution substation communication network according to the present invention.

Fig. 5 is a schematic structural diagram of a fifth embodiment of the low-voltage distribution substation communication network according to the present invention.

Fig. 6 is a schematic structural diagram of a sixth embodiment of a low-voltage distribution substation communication network according to the present invention.

Fig. 7 is a schematic structural diagram of a seventh embodiment of a low-voltage distribution substation communication network according to the present invention.

Fig. 8 is a schematic diagram of a two-layer sub-network structure of a seventh embodiment of a low-voltage distribution substation area communication network according to the present invention.

Fig. 9 is a schematic structural diagram of an eighth embodiment of a low-voltage distribution substation communication network according to the present invention.

Detailed Description

Features and exemplary embodiments of various aspects of the present invention will be described in detail below. In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. It will be apparent, however, to one skilled in the art that the present invention may be practiced without some of these specific details. The following description of the embodiments is merely intended to provide a better understanding of the present invention by illustrating examples of the present invention. The present invention is in no way limited to any specific configuration set forth below, but rather covers any modification, replacement or improvement of elements, components without departing from the spirit of the invention.

First embodiment

As shown in fig. 1, the present embodiment discloses a low-voltage distribution substation communication network applying an HPLC communication sub-network, and the communication network includes a centralized control unit 1, a slave node 2, and a communication host 3. The centralized control unit 1 is located inside a master switch 4, the number of the centralized control unit 1 is the same as that of the master switch 4, the centralized control unit 1 and the master switch 4 are arranged in a one-to-one correspondence manner, the slave nodes 2 are located inside branch switches 5, the number of the slave nodes 2 is the same as that of the branch switches 5, and the slave nodes 5 are arranged in a one-to-one correspondence manner, one centralized control unit 1 can correspond to one or more slave nodes 2, the branch switches 5 are subordinate units of the master switch 4, one master switch 4 can correspond to one or more branch switches 5, and when the master switch 4 corresponds to a plurality of branch switches 5, one centralized control unit 1 corresponds to a plurality of slave nodes 2.

Specifically, in this embodiment, the centralized control unit 1 may receive information of a plurality of slave nodes 2, buffer the information, and transmit the information to the communication host 3, and one centralized control unit 1 and a plurality of slave nodes 2 may form one communication sub-network, and the communication between the two is performed by using an HPLC method.

In this embodiment, the centralized control unit 1 is disposed inside the master switch 4, and the centralized control unit 1 can directly acquire the information of the master switch 4 in addition to receiving the information sent by the slave node 2,

the slave node 2 may acquire part or all of the electrical quantity, fault event, state quantity, terminal temperature information of the branch switch 5 corresponding thereto. The centralized control unit 1 may receive the information of the branch switches 5 acquired from the nodes 2, perform non-transient protection and/or monitoring alarm calculation according to the corresponding switch device classification, and send out corresponding control instructions and/or fault event records.

The electrical quantity information of the branch switch 5 corresponding to the slave node 2, which can be obtained from the slave node, includes partial or all information of voltage, current, active power, reactive power, power factor, frequency, residual current and harmonic inside the branch switch 5; the fault event information of the branch switch 5 comprises overload trip, short-circuit trip and residual current protection self-checking fault; the state quantity information of the branch switch 5 includes switching-on and switching-off (manual switching-off and electric switching-off) state information.

Further, the slave node 2 may also receive the setting information and the control information from the central control unit 1 and transmit the setting information and the control information to the branch switch 5, and in another preferred embodiment, when the slave node 2 is also provided in the master switch 4, the slave node 2 may transmit the setting information and the control information received from the central control unit 1 to the master switch 4.

The communication host 3 is electrically connected to the centralized control unit 1 and the branch switch 4, specifically, the centralized control unit 1 includes an uplink HPLC channel and a downlink HPLC channel, the uplink HPLC channel is electrically connected to the communication host 3, the centralized control unit 1 communicates with the communication host 3 through the uplink HPLC channel, and communicates with the slave node 2 through the downlink HPLC channel.

The communication host 3 distributes levels to the centralized control units 1 of the sub-networks according to corresponding sequences, all the sub-networks are mutually communicated through the centralized control units 1, the slave nodes 2 in the star network are all responsible for the centralized control units 1 of the network, and the communication host 3 is mainly responsible for effective communication with all the centralized control units 1 and data acquisition and monitoring, so that the data acquisition efficiency of the communication host in the transformer area is improved to a certain extent, and the number of monitored nodes is greatly reduced. During data transmission, all levels of subnets work well and orderly, the lower level subnets transmit data to the centralized control unit 1 of the upper level subnets, and simultaneously transmit data broadcast to the lower level subnets, so that the data collision rate is reduced.

The application devices of the communication network in this embodiment include, but are not limited to, JP cabinets, low-voltage switch cabinets, metering boxes, feeder cabinets, distribution boxes, and the like.

For a low-voltage distribution substation communication network applying an HPLC communication sub-network, a data transmission protocol needs to be specified. Firstly, the structure of a data packet should be designed aiming at a data structure, and the data packet mainly comprises the following parts: frame header, data original address, destination address, subnet center node address, node data, frame tail, etc. The frame head is used to mark the initial position of the data frame, the data source address is the address mark of the data sending source node, the central node address of the subnet represents the central point address of each level of the subnet, the node data is the data main body to be sent, and the frame tail is used to mark the end position of the data frame. Secondly, a specific flow of data transmission is designed.

The network maintenance principle of the networking process comprises the following steps: the state monitoring of the slave nodes 2 in each level of sub-network is all responsible for the centralized control unit 1 in the sub-network, and the operation state of the centralized control unit 1 in each level of sub-network is responsible for the communication host 3. In the network operation, the communication change of the slave node 2 in the local range is reconstructed by local routing, the local reconstruction cannot be solved, and then the whole network is reconstructed. When any new node in the network joins or the original node exits, the network initiates route reconstruction. When the network is idle, the networking monitoring information is continuously sent into the network, and when the information detects that the node changes, the route reconstruction is initiated.

Since the power line was originally designed for power transmission rather than information transmission, the signal is greatly disturbed during communication. The invention adopts a channel coding mode based on a majority discrimination method, thereby greatly reducing the probability of data error. During encoding, each data bit is extended to 8 bit data bits. When a data packet is decoded at a receiving end, adding operation is carried out on bit data in any byte, when more than five 1 s are accumulated, the byte can be analyzed to be 1, otherwise, the corresponding analysis is 0.

The uplink HPLC channel and the downlink HPLC channel of the centralized control unit 1 in the low-voltage distribution transformer area communication network are physically isolated. The design can isolate the noise between the uplink HPLC channel and the downlink HPLC channel, so that the communication channel impedance is regular, the communication rate is improved, and the error rate is reduced. Isolation from the power line from node 2.

In a preferred embodiment, the central control unit 1 has a relay function. After receiving the signal sent from the slave node 2, the centralized control unit 1 first amplifies the received signal, and when the signal reaches a certain strength, transmits the signal to the centralized control unit 1 or the communication host 3 of another peer. When a plurality of centralized control units 1 at the same level are arranged, an optimal transmission path can be automatically selected when data transmission is carried out, signals amplified by the relay of the centralized control units 1 can be transmitted to the centralized control units at other levels when being retransmitted, and the signals are finally transmitted to the communication host 3 after being amplified by the relay of the centralized control units at the same level again. The method greatly improves the transmission distance of the signal, and simultaneously avoids the influence of the enhanced signal power on the surrounding environment.

In a preferred embodiment, a current collector is disposed on the N lines of the power distribution system for detecting a current value flowing through the N lines. If the current value on the N line is detected to be not zero, the N line can be judged to be not broken; if the current value on the N line is detected to be equal to zero, the N line is disconnected or unloaded or A, B, C is in a complete balance condition of the three-phase circuit. At this time, it is necessary to comprehensively determine the A, B, C three-phase current value and the current value on the N line. In addition to the N-line disconnection protection method described above, the N-disconnection protection can also be determined according to a threshold value of the phase angle difference.

In this embodiment, the application layer of the low-voltage distribution substation communication network is provided with a topology identification function, and a typical low-voltage substation topology structure is restored by using a current matching algorithm, and the topology structure is matched with a physical topology structure of a low-voltage substation power line. The process can realize local automatic topology identification, and provides basic support for line loss analysis and electricity stealing protection through the integration of the node of the centralized control unit and the topological complete structure of the distribution room. In this embodiment, the application layer of the low-voltage distribution substation communication network is provided with a phase recognition function, and a phase relationship in a typical low-voltage substation topology is restored by using a current phase angle matching algorithm.

The low-voltage distribution substation communication network in the embodiment can also realize the functions of residual current detection, automatic topology identification, line loss analysis, electricity stealing protection and the like.

Second embodiment

Fig. 2 is a schematic diagram of a communication network of a low-voltage distribution substation using an HPLC communication sub-network according to a second embodiment. Different from the first embodiment, the centralized control unit 1 in this embodiment is disposed outside the main switch 4, specifically, the centralized control unit 1 is disposed on one side of the main switch 4 in parallel and connected to the main switch 4 through a clamping device, that is: the centralized control unit 1 is laterally hung with the main switch 4, and the slave node 2 is arranged inside the branch switch 5.

The slave node 2 may obtain part or all of the electrical quantity, fault event, state quantity, terminal temperature information of the branch switch 5. The centralized control unit 1 receives the information of each slave node 2, and carries out the calculation of non-transient protection and/or monitoring alarm according to the classification of the corresponding switch device, and sends out a corresponding control command and/or fault event record.

The centralized control unit 1 receives information of a plurality of slave nodes 2, transmits the received information to the communication host 3 after buffering, and the centralized control unit 1 and the plurality of slave nodes 2 form a communication sub-network in which the communication method adopts HPLC.

The advantage of the second embodiment is that the centralized control unit 1 is arranged on the side of the main switch 4, the position is more flexible, and the centralized control unit can be adjusted according to different designs.

Third embodiment

As shown in fig. 3, a low voltage distribution substation communication network employing an HPLC communication sub-network of a third embodiment is disclosed. Different from the first embodiment, in the third embodiment, the centralized control unit 1 and the communication host 3 are respectively arranged inside the box transformer substation 6, the box transformer substation 6 is a superior unit of the main switch 4, and the slave nodes 2 are respectively arranged inside the main switch 4 and the branch switches 5.

The slave node 2 may acquire part or all of the electrical quantity, fault event, state quantity, terminal temperature information of the master switch 4 and the branch switches 5, respectively. The slave nodes 2 are not communicated with each other, and are respectively communicated with the centralized control unit 1, and the centralized control unit 1 receives the acquired information of the slave nodes 2, calculates non-transient protection and/or monitoring alarm according to the corresponding switch equipment classification, and sends out corresponding control instructions and/or fault event records.

The centralized control unit 1 receives the information of the plurality of slave nodes 2, transmits the information to the communication host 3 after buffering, and the centralized control unit 1 and the plurality of slave nodes 2 form a communication sub-network in a communication mode of HPLC.

The third embodiment has the advantages that the centralized control unit 1 and the communication host 3 are simultaneously located in the box transformer substation 6, the connection between the centralized control unit 1 and the communication host 3 is more stable, and the survivability of the network is enhanced. When a connection between a slave node 2 and the centralized control unit 1 fails, the whole communication network is not significantly affected.

Fourth embodiment

As shown in fig. 4, a low voltage distribution substation communication network employing an HPLC communication sub-network of a fourth embodiment is disclosed. Unlike the third embodiment, the central control unit 1 in the fourth embodiment is disposed inside a JP cabinet 7, the JP cabinet 7 is a superior unit of the main switch 4, and the slave node 2 is disposed inside the main switch 4 and the branch switch 5, that is: and slave nodes 2 are correspondingly arranged in the main switch 4 and the branch switches 5.

The slave node 2 may acquire part or all of the electrical quantity, fault event, state quantity, terminal temperature information of the master switch 4 and the branch switches 5 corresponding thereto, respectively. The centralized control unit 1 receives the information of each slave node 2, and performs the calculation of non-transient protection and/or monitoring alarms according to the corresponding switchgear classification, and sends out corresponding control commands and/or fault event records.

The centralized control unit 1 receives information of a plurality of slave nodes 2, transmits the information to the communication host 3 after buffering, and forms a communication sub-network with the plurality of slave nodes 2 by the centralized control unit 1 in a communication mode of HPLC. The advantage of this embodiment lies in that centralized control unit 1 and communication host 3 are located JP cabinet 7 simultaneously, and the connection of centralized control unit 1 and communication host 3 is more stable, has strengthened the survivability of network. When a connection between a slave node 2 and the centralized control unit 1 fails, the whole communication network is not significantly affected.

Fifth embodiment

Fig. 5 shows a low-voltage distribution area communication network using an HPLC communication sub-network according to a fifth embodiment. Unlike the first embodiment, the slave node 2 is provided on the side of the branch switch 5 in the present embodiment, that is: the slave node 2 is arranged outside the branch switch 5, is arranged in parallel at one side of the branch switch 5, and is connected with the branch switch 5 through a connecting mechanism.

The centralized control unit 1 is arranged inside the main switch 4.

The slave node 2 may obtain part or all of the electrical quantity, fault event, state quantity, terminal temperature information of the corresponding branch switch 5. The centralized control unit 1 receives the information of each slave node 2, and performs the calculation of non-transient protection and/or monitoring alarms according to the corresponding switchgear classification, and sends out corresponding control commands and/or fault event records.

The centralized control unit 1 receives information of a plurality of slave nodes 2, transmits the received information to the communication host 3 after buffering, and the centralized control unit 1 and the plurality of slave nodes 2 form a communication sub-network in which the communication mode adopts HPLC.

The advantage of this embodiment is that the slave node 2 is arranged on the side of the branch switch 5, the position is more flexible, and the slave node can be adjusted according to different designs.

Sixth embodiment

As shown in fig. 6, a low voltage distribution substation communication network employing an HPLC communication sub-network of a sixth embodiment is disclosed. Unlike the first embodiment, the slave nodes 2 in this embodiment are respectively disposed inside the master switch 4 and the branch switch 5, and the central control unit 1 and the communication master 3 are respectively disposed inside the box transformer substation 6.

The plurality of slave nodes 2 can respectively acquire part or all of the electrical quantity, fault event, state quantity, and terminal temperature information of the master switch 4 and the branch switches 5 corresponding thereto. The centralized control unit 1 receives the information of each slave node 2, and performs the calculation of non-transient protection and/or monitoring alarms according to the corresponding switchgear classification, and sends out corresponding control commands and/or fault event records.

The centralized control unit 1 receives information of a plurality of slave nodes 2, transmits the information to the communication host 3 after buffering, and forms a communication sub-network with the plurality of slave nodes 2 by the centralized control unit 1 in a communication mode of HPLC.

The advantage of this embodiment is that the slave nodes 2 can be respectively arranged inside the side-hang switch and the branch switch 5 of the master switch 4, the position is more flexible, and the slave nodes can be adjusted according to different designs.

The first to sixth embodiments show embodiments in which the centralized control unit 1 and the slave node 2 are located at different positions, respectively, and include that the centralized control unit 1 is disposed inside the box transformer 6, or inside the JP cabinet 7, or inside/side-hanging the master switch 4, and the slave node 2 is disposed inside/side-hanging the master switch 4, and/or inside/side-hanging the branch switch 5. The positions of the centralized control unit 1 and the slave nodes 2 are matched arbitrarily, and new schemes can be combined, and the generated new schemes are all included in the scope claimed by the invention.

Seventh embodiment

Fig. 7 shows a communication network of a low-voltage distribution area using an HPLC communication sub-network according to a seventh embodiment. Unlike the first embodiment, two layers of sub-networks are designed in this embodiment. As shown in fig. 7, the central control unit 1 and the slave node 2 in the dashed line box a are the first-layer sub-networks, the central control unit 1 and the slave node 2 in the dashed line box B are the second-layer sub-networks, the central control unit 1 of the second-layer sub-network is connected to the central control unit 1 of the first-layer sub-network, and the two are connected by the communication method of HPLC.

Similarly, the first-layer sub-network is not limited to being connected to one second-layer sub-network, and a plurality of second-layer sub-networks may be simultaneously connected to the first-layer sub-network.

The application scenarios of the first layer sub-network include, but are not limited to, feeder cabinets, JP cabinets, low-voltage switch cabinets, metering boxes, distribution boxes and the like. The application scenarios of the second layer sub-network include, but are not limited to, a distribution box, a JP cabinet, a low-voltage switch cabinet, a metering box, a feeder cabinet, and the like.

The present embodiment is advantageous in that it is applicable to a two-tier structure in which one or more wire closets are connected by one wire closet at the same time. Each wiring cabinet can form a sub-network, networking is simple, and network connection is stable.

Fig. 8 is a schematic diagram of a two-layer subnetwork structure. The central control unit 1 is located at position 1 indicated in fig. 8, and the slave nodes 2 are located at positions 21, 22, 23, 24, 25, 26, 27 indicated in fig. 8. The connection relationship between the slave node 2 and the centralized control unit 1 depends on the specific application scenario. The type and number of circuit breakers shown in fig. 8 are only one example, and other communication networks with different types and numbers of circuit breakers are included in the scope of the present invention.

Eighth embodiment

Fig. 9 is a schematic diagram of a communication network of a low-voltage distribution substation using an HPLC communication sub-network according to an eighth embodiment. In contrast to the seventh embodiment, the eighth embodiment designs three layers of sub-networks. As shown in fig. 9, the centralized control unit 1 and the slave node 2 in the dashed line box C are the first-layer sub-networks, the centralized control unit 1 and the slave node 2 in the dashed line box D are the second-layer sub-networks, and the centralized control unit 1 and the slave node 2 in the dashed line box E are the third-layer sub-networks. The centralized control unit 1 of the second-layer sub-network is connected with the centralized control unit 1 of the first-layer sub-network, and the star point unit 1 of the third-layer sub-network is connected with the centralized control unit 1 of the second-layer sub-network.

Similarly, the first-layer sub-network is not limited to being connected to one second-layer sub-network, and a plurality of second-layer sub-networks may be simultaneously connected to the first-layer sub-network. The layer two sub-network is not limited to connecting one layer three sub-network, and a plurality of layer three sub-networks may be connected simultaneously in the layer two sub-network. The number of hierarchical levels of the sub-networks is not limited to three, and a plurality of layers may be connected. The application scenarios of the sub-networks at each level include, but are not limited to, a tap box, a JP cabinet, a low-voltage switch cabinet, a metering box, a feeder cabinet, and the like.

The embodiment has the advantages that the number of the sub-network hierarchies is large, and the rapid networking based on the combination of the ant colony algorithm and the clustering algorithm is favorably realized. In a network consisting of the centralized control unit 1 and the communication host 3, an optimal path for information transfer is established mainly according to an ant colony algorithm. Inside the sub-network, the networking is mainly carried out according to a clustering algorithm, and when a certain slave node 2 is changed or replaced, the sub-network is subjected to new networking.

Claims (14)

1. The communication network of the low-voltage distribution station area applying the HPLC communication sub-network is characterized by comprising at least one centralized control unit (1) and a plurality of slave nodes (2), wherein the power supply of the centralized control unit (1) is collected in a main circuit (31) through a conducting circuit (21), the power supply of the slave nodes (2) is supplied by the centralized control unit (1), the centralized control unit (1) can receive the information of the plurality of slave nodes (2), can transmit the information to a communication host (3) in a wired or wireless mode after buffer processing, the centralized control unit (1) and the plurality of slave nodes (2) form a communication sub-network, and the communication sub-network are communicated in the HPLC communication mode.

2. Communication network of low voltage distribution substations using HPLC communication sub-networks, according to claim 1, characterized in that the centralized control unit (1) and/or the slave nodes (2) transmit information such as the electric or non-electric quantity or parameter settings of the main circuit of the low voltage distribution substation, and transmit part or all of the data of said information by means of carrier communication over the circuits of one of the communication sub-networks other than the main circuit.

3. Communication network of low voltage distribution substations using an HPLC communication sub-network according to claim 1, characterized in that the line in the HPLC communication sub-network, which communicates by HPLC between the centralized control unit (1) and the slave node (2), is also the power supply line for the centralized control unit (1) to supply power to the functional modules and electronics on the slave node (2).

4. Communication network of low voltage distribution areas applying HPLC communication sub-networks, according to claim 1, further comprising master switches (4) and branch switches (5), wherein said centralized control unit (1) or/and said slave nodes (2) can obtain part or all of the information of electrical quantities, fault events, state quantities, terminal temperatures on the master circuits of said master switches (4) and/or said branch switches (5), the operating power supply of said centralized control unit (1) and/or slave nodes (2) being decoupled from the operating state of said master switches (4) and/or branch switches (5).

5. Communication network of low voltage distribution substations using an HPLC communication sub-network according to claim 2, characterized in that the slave nodes (2) can receive setting information, control information from the central control unit (1) and pass to the corresponding master switch (4) and/or the branch switches (5).

6. Communication network of low voltage distribution substations using HPLC communication sub-networks, according to claim 1, characterized in that the upstream channel of the centralized control unit (1) is physically isolated from the downstream HPLC channel, and can be connected to the communication master (3) by wired or wireless means; when the uplink channel adopts an HPLC communication mode, the uplink channel is connected to a power line of a low-voltage power distribution station area.

7. Communication network of low voltage distribution substations using HPLC communication sub-networks according to claim 1, characterized in that the centralized control unit (1) has a relay function.

8. Communication network of low voltage distribution substations applying an HPLC communication sub-network according to claim 1, characterized in that the slave node (2) is isolated from the power line.

9. Communication network of low voltage distribution substations using HPLC communication sub-networks, according to claim 2, characterized in that the centralized control unit (1) can be arranged at least one of inside a box transformer (6), inside a JP cabinet (7), inside a main switch (4) or in side-hanging relation to the main switch (4).

10. Communication network of low voltage distribution substations applying an HPLC communication sub-network according to claim 2 or 7, characterized in that the slave node (2) is arranged inside the master switch (4) and/or the branch switch (5) or is side-hung from the master switch (4) and/or the branch switch (5).

11. A communication network of low voltage distribution substations using HPLC communication sub-network according to claim 2, characterized in that at its application level there is provided a topology identification function, using a current matching algorithm to restore a typical low voltage substation topology, which coincides with the physical topology of the low voltage substation power lines.

12. A communication network for low voltage distribution substations using HPLC communication sub-networks, according to claim 2, characterized in that a phase recognition function is provided at its application level, and the phase relationships in the typical low voltage substation topology are restored using a galvanic phase angle matching algorithm.

13. Communication network of low voltage distribution areas using HPLC communication sub-networks according to claim 1, characterized by the fact that a plurality of HPLC communication sub-networks and a number of central control units (1) equal to the number of HPLC communication sub-networks can be provided, the central control units (1) corresponding to the settings of the typical application in which they are installed respectively.

14. Communication network of low voltage distribution substations using an HPLC communication subnetwork as claimed in claim 3, characterized in that said centralized control unit (1) receives information of each slave node and performs non-instantaneous protection and/or monitoring alarm calculations according to the corresponding switchgear classification and issues corresponding control commands and/or fault event records.

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