CN110932396A - Low-voltage distribution network topology identification system based on pulse characteristic current signals - Google Patents
Low-voltage distribution network topology identification system based on pulse characteristic current signals Download PDFInfo
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- CN110932396A CN110932396A CN201911169855.6A CN201911169855A CN110932396A CN 110932396 A CN110932396 A CN 110932396A CN 201911169855 A CN201911169855 A CN 201911169855A CN 110932396 A CN110932396 A CN 110932396A
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- G—PHYSICS
- G08—SIGNALLING
- G08C—TRANSMISSION SYSTEMS FOR MEASURED VALUES, CONTROL OR SIMILAR SIGNALS
- G08C19/00—Electric signal transmission systems
- G08C19/16—Electric signal transmission systems in which transmission is by pulses
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- H04B3/544—Setting up communications; Call and signalling arrangements
Abstract
The invention discloses a low-voltage distribution network topology identification system based on pulse characteristic current signals.A bus current centralized controller is installed on a low-voltage incoming line switch layer; the low-voltage outlet switch layer is provided with a plurality of branch current detectors, the branch switch layer is provided with a plurality of branch current detectors, the user switch layer of the metering box is provided with a plurality of branch current detectors, and the tail end of a user is provided with a pulse characteristic current generator; on the basis of not changing the original circuit, the bus current integrated controller is installed at the master switch, and the branch current detectors and the pulse characteristic current generators are respectively installed at the tail ends of all the branches and the power distribution network users, so that the low-voltage power distribution network topological structure is obtained, the change of the power distribution network topological structure can be monitored in real time on line, the real-time monitoring and reporting of the low-voltage power distribution network topological structure are realized, and the improvement of the power supply reliability and the power grid operation and maintenance management level is facilitated.
Description
Technical Field
The invention relates to a power distribution network topology structure recognition system, in particular to a low-voltage power distribution network topology recognition system based on pulse current characteristic signals.
Background
With the development of the ubiquitous power internet of things and the continuous improvement of the power quality requirements of users, how to improve the power supply reliability and the production management level of a power distribution network becomes a big problem in the power industry. The realization of data sharing and comprehensive utilization between marketing and operation and maintenance service systems becomes an effective way for solving the problem. The basic work is to establish a topological relation between distribution-line-household, perfect account information of the low-voltage equipment, improve the information sharing degree of each department of the power company, and further improve the power supply reliability and the distribution network operation and maintenance management level.
In a certain sense, the topological relation of the low-voltage distribution network refers to the topological relation among the outgoing lines from the low-voltage side of the distribution transformer → the low-voltage switch cabinet → each branch main switch → each user access point. Due to the reason of management and line transformation, the topological relation between outgoing lines of a distribution transformer and users of many old cells is unclear or incorrect, and corresponding signboards are lacked or are not clear in writing, so that certain difficulty is caused for establishing the topological relation of the low-voltage distribution network.
In addition, for a low-voltage power distribution network with a known topological structure, monitoring the change condition of the topological structure of the power supply network in time is also an important aspect of power grid operation and maintenance management.
Disclosure of Invention
The invention aims to solve the technical problem of providing a low-voltage distribution network topology identification system based on pulse characteristic current signals, which is convenient for establishing a clear topology relation of a low-voltage distribution network.
In order to solve the technical problems, the technical scheme of the invention is as follows: the low-voltage distribution network topology identification system based on the pulse characteristic current signals comprises a low-voltage incoming line switch layer, a low-voltage outgoing line switch layer, a plurality of branch line switch layers and a metering box user switch layer; a bus current centralized controller is installed on the low-voltage incoming line switch layer; the low-voltage outlet switch layer is provided with a plurality of branch current detectors which are in one-to-one correspondence with the low-voltage outlet switches, the branch switch layer is provided with a plurality of branch current detectors which are in one-to-one correspondence with the branch switches, and the metering box user switch layer is provided with a plurality of branch current detectors which are in one-to-one correspondence with the metering box switches and pulse characteristic current generators which are in one-to-one correspondence with the user tail ends; the bus current centralized controller, the branch current detector and the pulse characteristic current generator are all configured with carrier communication modules for power carrier communication, and the branch current detector and the pulse characteristic current generator are all provided with address codes and written in the bus current centralized controller.
As a preferred technical scheme, a branch current detector is installed at a meter box switch outlet end of a meter box user switch layer, and the pulse characteristic current generator is installed at a user tail end of the meter box user switch layer.
As a preferred technical scheme, the pulse characteristic current generator comprises a power carrier communication module, the power carrier communication module is connected with an embedded single-chip microcomputer control system, the embedded single-chip microcomputer control system is connected with an IGBT impedance load circuit, and the IGBT impedance load circuit is connected with an AC220V branch circuit to be detected.
As a preferable technical scheme, the amplitude of the pulse current generated by the pulse characteristic current generator is 0.1-20A, the pulse width is 0.01-10 ms, and the number of the pulse to be sent in each power frequency period is 1-1000 in a timing and synchronous mode.
As a preferable technical solution, the branch current detector includes an open-close type 0.5S class current transformer and a pulse filter.
As a preferred technical solution, the bus current centralized controller includes an embedded control module, a carrier communication module, and a bus current detection module.
As a preferred technical solution, the branch current detector includes an embedded control module, a branch current detection module, and a carrier communication module.
By adopting the technical scheme, the low-voltage distribution network topology identification system based on the pulse characteristic current signals comprises a low-voltage incoming line switch layer, a low-voltage outgoing line switch layer, a plurality of branch line switch layers and a metering box user switch layer; a bus current centralized controller is installed on the low-voltage incoming line switch layer; the low-voltage outlet switch layer is provided with a plurality of branch current detectors which are in one-to-one correspondence with the low-voltage outlet switches, the branch switch layer is provided with a plurality of branch current detectors which are in one-to-one correspondence with the branch switches, and the metering box user switch layer is provided with a plurality of branch current detectors which are in one-to-one correspondence with the metering box switches and pulse characteristic current generators which are in one-to-one correspondence with the user tail ends; the bus current centralized controller, the branch current detector and the pulse characteristic current generator are all configured with carrier communication modules for power carrier communication, and the branch current detector and the pulse characteristic current generator are all provided with address codes and written into the bus current centralized controller; on the basis of not changing the original circuit, a low-voltage distribution network topological structure is obtained by installing a bus current centralized controller at a master switch and respectively installing branch current detectors and pulse characteristic current generators at the tail ends of all branches and distribution network users, the change of the distribution network topological structure can be monitored in real time on line, the low-voltage distribution network topological structure can be monitored and reported in real time, and the improvement of power supply reliability and the operation and maintenance management level of a power grid is facilitated.
Drawings
The drawings are only for purposes of illustrating and explaining the present invention and are not to be construed as limiting the scope of the present invention. Wherein:
FIG. 1 is a schematic circuit diagram of an embodiment of the present invention;
FIG. 2 is a block diagram of a pulse signature current signal generator according to an embodiment of the present invention;
in the figure: 11-low voltage incoming line switch; 12-low voltage outlet switch; 13-a branch line switch; 14-batch tank switch.
Detailed Description
The invention is further illustrated below with reference to the figures and examples. In the following detailed description, certain exemplary embodiments of the present invention are described by way of illustration only. Needless to say, a person skilled in the art realizes that the described embodiments can be modified in various different ways without departing from the spirit and scope of the present invention. Accordingly, the drawings and description are illustrative in nature and not intended to limit the scope of the claims.
As shown in fig. 1, the low-voltage distribution network topology identification system based on pulse characteristic current signals includes a low-voltage incoming line switch layer, a low-voltage outgoing line switch layer, a plurality of branch line switch layers and a metering box user switch layer; a bus current centralized controller is installed on the low-voltage incoming line switch layer, and is connected with an incoming line end of the low-voltage incoming line switch 11; a plurality of branch current detectors which are in one-to-one correspondence with the low-voltage outlet switches 12 are installed on the low-voltage outlet switch layer, a plurality of branch current detectors which are in one-to-one correspondence with the branch switches 13 are installed on the branch switch layer, and a plurality of branch current detectors which are in one-to-one correspondence with the metering box switches 14 and pulse characteristic current generators which are in one-to-one correspondence with the tail ends of users are installed on the metering box user switch layer; the bus current centralized controller, the branch current detector and the pulse characteristic current generator are all configured with carrier communication modules for power carrier communication, and the branch current detector and the pulse characteristic current generator are all provided with address codes and written in the bus current centralized controller.
And a branch current detector is installed at the outlet end of a metering box switch 14 of the metering box user switch layer, and the pulse characteristic current generator is installed at the end of a user of the metering box user switch layer. As shown in fig. 2, the pulse characteristic current generator includes a power carrier communication module, the power carrier communication module is connected with an embedded single-chip microcomputer control system, the embedded single-chip microcomputer control system is connected with an IGBT impedance load circuit, and the IGBT impedance load circuit is connected with an AC220V branch circuit to be detected. The amplitude of the pulse current generated by the pulse characteristic current generator is 0.1-20A, the pulse width is 0.01-10 ms, and the number of the pulse sent in each power frequency period in a timing and synchronous mode is 1-1000.
The branch current detector comprises an open-close type 0.5S-level current transformer and a pulse filter. The bus current centralized controller comprises an embedded control module, a carrier communication module and a bus current detection module. The branch current detector comprises an embedded control module, a branch current detection module and a carrier communication module.
The low-voltage output of the user transformer is controlled by one-stage or multi-stage switches, the switches are used as dividing lines, if the branch at the tail end of the connected load is set to be n layers, the topological structure of the low-voltage power supply network can be divided into K0, K1, K2, K3 and K4 … … Kn-1 layers according to the level of the control switch, and one or more power supply branches can be connected below each switch. In order to explain the principle of the invention, the low-voltage power supply topological structure is divided into four layers for explanation, namely a low-voltage incoming line switch layer, a low-voltage outgoing line switch layer, a branch line switch layer and a metering box user switch layer.
The low-voltage distribution network topology identification system based on the pulse characteristic current signals has the following characteristics:
1. under the condition that each part has power line carrier communication, a bus current centralized controller is installed at the incoming line end of a low-voltage incoming line switch 11 of a low-voltage incoming line switch layer; a branch current detector is arranged at the wire inlet end of a low-voltage wire outlet switch 12 of the low-voltage wire outlet switch layer, and a branch current detector is arranged at the wire outlet end of a branch switch 13 of the branch switch layer; a branch current detector is arranged at the outlet end of a metering box switch 14 of a user switch layer of the metering box; and installing a pulse characteristic current generator at the end of a power distribution network user.
2. An easily-identified pulse characteristic current generator is arranged on a branch at the tail end of the power distribution network, and easily-identified pulse characteristic current is generated between a phase line and a zero line and comprises the amplitude, the phase and the change characteristics of power frequency waveform distortion of the power frequency current; the pulse characteristic current generator consists of an embedded single-chip microcomputer control system, a power carrier communication module, an IGBT module and load impedance;
3. the pulse characteristic current generator has an embedded control structure and a carrier communication function, and the on-off of the current generator is controlled by the bus current centralized controller;
4. the pulse characteristic current generator generates pulse current with the amplitude of 0.1-20A and the pulse width of 0.01-10 ms, and the number of transmitted pulses in each power frequency period is 1-1000;
5. the bus current centralized controller, each branch current detector and the distribution network tail end pulse characteristic current generator are all provided with carrier communication modules, and power carrier communication is carried out through a power supply circuit of the distribution area;
6. the branch current detector consists of an open-close type 0.5S-level current transformer and a pulse filter, and can detect the pulse number, amplitude and pulse width of the characteristic current of the branch except the power frequency current;
7. the branch current detector and the distribution network tail end pulse characteristic current generator which are arranged on each branch have definite address codes.
After the bus current integrated controller sends a switching-on instruction to the tail end pulse characteristic current generators of the power distribution network, whether pulse characteristic currents flow through the branches of the branch current detectors is detected one by one, all the tail end pulse characteristic current generators are started one by one in a time-sharing mode, and then the topological structure of the power supply network is determined by utilizing a logical relation through collection of branch data through which the pulse characteristic currents flow.
On the basis of not changing the original circuit, the bus current integrated controller is installed at the master switch, and the branch current detectors and the pulse characteristic current generators are respectively installed at the tail ends of the branches and the power distribution network, so that the topological structure of the low-voltage power distribution network is obtained, the change of the topological structure of the power distribution network can be monitored in real time on line, the real-time monitoring and reporting of the topological structure of the low-voltage power distribution network are realized, and the improvement of the power supply reliability and the operation and maintenance management level of the power grid is facilitated.
The bus current centralized controller, the branch current detector and the pulse characteristic current generator all have an online installation function.
The identification method of the low-voltage distribution network topology identification system based on the pulse characteristic current signal comprises the following steps:
step one, a bus current integrated controller sends a switching-on instruction to a pulse characteristic current generator at a user terminal, each branch current detector monitors current state information of the branch in real time, and the current information of the branch is uploaded to the bus current integrated controller through a carrier communication module of the branch;
step two, the bus current integrated controller senses that pulse characteristic current flows through the branch current detectors of the branch, and records address codes of the branch current detectors flowing through the pulse characteristic current; then sending turn-on instructions to pulse characteristic current generators at the tail ends of other users one by one in a time-sharing manner;
and step three, the bus current integrated controller obtains the topological structure of the corresponding power supply area and the change condition of each branch circuit through logic calculation according to the pulse characteristic current generator and the address code of the branch circuit current detector through which the characteristic current flows, and completes the online identification and monitoring of the topology of the area.
The principle of online current identification and monitoring is illustrated by way of example in fig. 1. The bus current centralized controller at the incoming line end of the bus switch K0 sends a switching-on command to a pulse characteristic current generator of a user branch K41, each branch current detector monitors the current state information of the branch in real time, the current information of the branch is uploaded to the bus current centralized controller through a carrier communication module, the bus current centralized controller senses that pulse characteristic currents flow through the branch current detectors of K11, K21 and K31, and records address codes of the branch current detectors flowing through the pulse characteristic currents; and then sending an opening instruction to the pulse characteristic current generators of K42-K46 one by one in a time-sharing manner. The bus current integrated controller obtains the topological structure of the corresponding power supply area and the change condition of each branch circuit through logic calculation according to the address codes of the pulse characteristic current generator and the branch circuit current detector through which the characteristic current flows, and completes the online identification and monitoring of the topology of the area.
For a distribution area with unknown power supply topological structure, a bus current centralized controller, a branch current detector and a terminal user layer pulse characteristic current generator can be installed on line, all branches are opened one by one in a circulating mode from the tail end of a power distribution network, and the current power supply network topological structure can be confirmed according to the logical relationship through the cooperation of switches at all levels.
A bus current centralized controller, a branch detector and a branch characteristic current generator for bus data acquisition all adopt a multifunctional open-close type combined transformer (patent application number: 201910981923.2), so that the current transformer can be easily installed, puncture insulation electricity taking can be facilitated, and only a zero line needs to be connected with a lead.
The foregoing shows and describes the general principles, essential features, and advantages of the invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are described in the specification and illustrated only to illustrate the principle of the present invention, but that various changes and modifications may be made therein without departing from the spirit and scope of the present invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.
Claims (7)
1. Low-voltage distribution network topology identification system based on pulse characteristic current signal, its characterized in that: the low-voltage distribution network comprises a low-voltage incoming line switch layer, a low-voltage outgoing line switch layer, a plurality of branch line switch layers and a metering box user switch layer; a bus current centralized controller is installed on the low-voltage incoming line switch layer; the low-voltage outlet switch layer is provided with a plurality of branch current detectors which are in one-to-one correspondence with the low-voltage outlet switches, the branch switch layer is provided with a plurality of branch current detectors which are in one-to-one correspondence with the branch switches, and the metering box user switch layer is provided with a plurality of branch current detectors which are in one-to-one correspondence with the metering box switches and pulse characteristic current generators which are in one-to-one correspondence with the user tail ends; the bus current centralized controller, the branch current detector and the pulse characteristic current generator are all configured with carrier communication modules for power carrier communication, and the branch current detector and the pulse characteristic current generator are all provided with address codes and written in the bus current centralized controller.
2. A low voltage distribution network topology identification system based on pulse characteristic current signals according to claim 1, characterized in that: the metering box switch leading-out terminal on the metering box user switch layer is provided with a branch current detector, and the user terminal on the metering box user switch layer is provided with the pulse characteristic current generator.
3. A low voltage distribution network topology identification system based on pulse characteristic current signals according to claim 1, characterized in that: the pulse characteristic current generator comprises a power carrier communication module, the power carrier communication module is connected with an embedded single-chip microcomputer control system, the embedded single-chip microcomputer control system is connected with an IGBT impedance load circuit, and the IGBT impedance load circuit is connected with an AC220V branch circuit to be detected.
4. A low voltage distribution network topology identification system based on pulse characteristic current signals according to claim 1, characterized in that: the amplitude of the pulse current generated by the pulse characteristic current generator is 0.1-20A, the pulse width is 0.01-10 ms, and the number of the pulse sent in each power frequency period in a timing and synchronous mode is 1-1000.
5. A low voltage distribution network topology identification system based on pulse characteristic current signals according to claim 1, characterized in that: the branch current detector comprises an open-close type 0.5S-level current transformer and a pulse filter.
6. A low voltage distribution network topology identification system based on pulse characteristic current signals according to claim 1, characterized in that: the bus current centralized controller comprises an embedded control module, a carrier communication module and a bus current detection module.
7. A low voltage distribution network topology identification system based on pulse characteristic current signals according to claim 1, characterized in that: the branch current detector comprises an embedded control module, a branch current detection module and a carrier communication module.
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| CN111404270A (en) * | 2020-04-02 | 2020-07-10 | 国电南瑞南京控制系统有限公司 | Low-voltage distribution area topology level identification method, device and equipment based on synchronous counting method |
| CN111463783A (en) * | 2020-04-29 | 2020-07-28 | 山东卓远智能科技有限公司 | Low-voltage distribution network topology identification and fault positioning device and application method |
| CN111682641A (en) * | 2020-06-02 | 2020-09-18 | 航天中电科技（北京）有限公司 | Charge control intelligent switch, charge control method and distribution room topology identification method |
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| CN111404270A (en) * | 2020-04-02 | 2020-07-10 | 国电南瑞南京控制系统有限公司 | Low-voltage distribution area topology level identification method, device and equipment based on synchronous counting method |
| CN111463783A (en) * | 2020-04-29 | 2020-07-28 | 山东卓远智能科技有限公司 | Low-voltage distribution network topology identification and fault positioning device and application method |
| CN111682641A (en) * | 2020-06-02 | 2020-09-18 | 航天中电科技（北京）有限公司 | Charge control intelligent switch, charge control method and distribution room topology identification method |
| CN112003635A (en) * | 2020-06-19 | 2020-11-27 | 浙江华云信息科技有限公司 | Networking and topology identification system and method under pure reactive current pulse signal |
| CN112003802A (en) * | 2020-06-19 | 2020-11-27 | 浙江华云信息科技有限公司 | Coding system and method using reactive current pulse |
| CN112003635B (en) * | 2020-06-19 | 2021-12-07 | 浙江华云信息科技有限公司 | Networking and topology identification system and method under pure reactive current pulse signal |
| CN112003802B (en) * | 2020-06-19 | 2023-09-19 | 浙江华云信息科技有限公司 | Coding system and method using reactive current pulse |
| CN112564981A (en) * | 2020-12-21 | 2021-03-26 | 国网青海省电力公司海北供电公司 | Topology identification method for electric elements of power distribution network |
| CN113809820A (en) * | 2021-07-30 | 2021-12-17 | 北京智芯微电子科技有限公司 | Method, device, system, medium and signal encoding method for identifying platform zone topology |
| CN114256974A (en) * | 2021-12-06 | 2022-03-29 | 青岛鼎信通讯股份有限公司 | Power-on-off rapid positioning method for transformer area based on common change of energy controller |
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