CN110940938A - Device and method for detecting connection relation between user electric meter and transformer - Google Patents
Device and method for detecting connection relation between user electric meter and transformer Download PDFInfo
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- CN110940938A CN110940938A CN201911107903.9A CN201911107903A CN110940938A CN 110940938 A CN110940938 A CN 110940938A CN 201911107903 A CN201911107903 A CN 201911107903A CN 110940938 A CN110940938 A CN 110940938A
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R19/00—Arrangements for measuring currents or voltages or for indicating presence or sign thereof
- G01R19/0084—Arrangements for measuring currents or voltages or for indicating presence or sign thereof measuring voltage only
Abstract
The invention relates to a device and a method for detecting the connection relation between a user electric meter and a transformer, wherein the detection device comprises: the voltage modulation part is arranged between the transformer outlet end of the transformer in the transformer area and a user line, and comprises a voltage modulation circuit and a controller, wherein the voltage modulation circuit comprises an anti-parallel diode and a bypass switch which are connected in parallel; the user electric meter data acquisition part is connected with the user electric meter and is used for acquiring voltage data of the user electric meter; and the user electric meter data analysis part is connected with the user electric meter data acquisition part and used for judging the transformer line relation to which the user electric meter belongs according to the voltage data. Compared with the prior art, the method has the advantages of simple structure, accurate and quick judgment result and the like.
Description
Technical Field
The invention relates to a transformer area identification method, in particular to a device and a method for detecting the connection relation between a user electric meter and a transformer.
Background
In recent years, with the continuous progress of urbanization development, residential districts are continuously increased, the power load is increased, and the number of newly-added transformer districts is huge, so that a plurality of technical problems are exposed, for example, illegal power utilization of some low-voltage users, private wiring circuits and the like exist, and the power utilization safety is seriously influenced. It is important to accurately identify the district transformer to which each consumer meter belongs and the phase line of the transformer to which the single-phase meter belongs. Therefore, there is an increasing need for an efficient way to identify the subscriber relationship of a cell.
Since old users frequently change connections and new users are increasing, it is necessary to perform station-to-station subscriber relationship identification every year. At an early stage, it requires field inspection by the staff of the electric company. In this way, staff need inspect the circuit and record manually, and the inefficiency easily leads to the mistake. Later, with the development of power line communication, an identification method based on power line communication was produced, in which information is modulated into a high frequency signal, and at the user side, the signal is received and demodulated by an additional device. However, high frequency signals are susceptible to attenuation and distortion due to long distances and load variations. Furthermore, high frequency signals may enter other areas through transformers and may couple with other lines, which may lead to misreadings. In order to solve the problem, researchers combine power line communication with pulse current, but the pulse current method has potential safety hazards, and workers still need to operate manually. Industrial frequency communication has also been proposed to overcome these drawbacks, however, in this method, additional devices are still required to be installed on the transformer and user side, and the solution is very complicated.
In summary, the current scheme used at home and abroad is as follows:
(1) power line carrier communication mode
The communication carrier of the cable carrier communication mode is a power line of a distribution network, and the station identification mode is to modulate high-frequency coding information at the outlet side of a distribution transformer, transmit the high-frequency coding information through the power line of the distribution network and reach a receiving device at a client side, so that the station attribution judgment and the phase sequence identification are realized. The method for identifying the transformer area has the advantages that the method can realize plug and play in the field operation process, the equipment does not need to be maintained, and the use is very convenient. The basic working principle is as follows:
the main communication device sends data to the outside, the data contains station area number and phase sequence information, the data enters the buffer area of the central processor through the interface, and modulation coding is carried out on the data, so that the data can be coupled to the power line of the low-voltage outlet of the power distribution network for transmission. The receiver of the user side is positioned at the other end of the power line, decouples the station area number and the phase information, receives the signals from the power line, decodes the signals through a built-in processor, performs secondary coding, and finally transmits the signals to the display through the communication interface.
The power line carrier communication mode is adopted for station area identification, and the station area identification generally comprises two parts in the actual operation process: a host; the medium for the hand-held terminal, the host and the terminal to contact is a carrier signal transmitted on a power line. The operation method comprises the following steps: firstly, an inspector installs a host at a low-voltage outlet terminal of a transformer to be detected or a metering box of a transformer area, and a terminal is installed at an inlet terminal of a user meter to be detected remotely. Taking three-phase voltage as an example, the host is connected to the transformer A, the terminal is supposed to be connected to the B-phase cable of the user to be detected, and the handheld terminal is also installed on the B-phase cable. The host computer sends a carrier signal to the handheld terminal, the handheld terminal receives the signal through the receiving device and displays the marking information and the phase information of the transformer A through the screen, and at the moment, the detected client belongs to the transformer A and is connected to the phase cable of the transformer B, so that the station area identification is realized. On the contrary, if the host is connected to other transformers and sends a carrier signal to the terminal, the terminal cannot receive the signal, which indicates that the detected user does not belong to the transformer in principle.
(2) By combining FSK power carrier signal method with pulse current method
The method adopts a mode of combining an FSK power carrier signal method and a pulse current method to judge the affiliation of a station area, and the basic principle is as follows: firstly, the hand-held terminal sends out a pulse current signal, the host machine detects the pulse current signal through the built-in pulse current detector, then re-encodes the signal, modulates a carrier signal and loads the carrier signal on a power line, and if the hand-held terminal receives the carrier signal, the user is powered by the transformer.
1) System architecture
The system principle of the method for identifying the transformer area is as follows: firstly, a handheld terminal sends a pulse current signal outwards, a host at a remote place actively triggers a power line carrier signal after detecting the pulse current signal through a pulse current detection device, codes identification numbers, phase sequences and other data of a distribution area, modulates the data into a carrier signal, and couples the carrier signal to a power line measured at a low-voltage outlet of a power distribution network for transmission. And the handheld terminal of the user side to be detected receives the carrier signal, decouples transformer information and the like transmitted by the host from the power line, analyzes and codes the transformer information and the like through the built-in processor, and displays the result in the display device.
2) In situ use
The device for identifying the transformer area by the pulse current method and the power line carrier communication is also composed of two parts: a host; provided is a handheld terminal. When the transformer is operated on site, the host is connected in the metering box of the distribution transformer area according to the sequence, and the pulse current detection clamp is clamped on the zero line cable of the transformer. And at the detected user end, the red clip of the handheld terminal is clamped on a live wire, the black clip is clamped on a zero wire, the waiting time is about 1 minute, and the transformer information and the phase sequence information which the detected client belongs to are displayed on the display of the terminal. This determines the zone affiliation of the client.
The two methods are very simple and intuitive for identifying the transformer area and are very wide in application, but in the actual use process, some problems are found, for example, the covered area of some transformer areas is large, buried cables are mutually crossed, the load of a line path causes the carrier signal to generate anti-interference in the transmission process, or the amplitude of the carrier signal is attenuated and the resolving power is reduced under the conditions of attenuation, noise and overweight load generated in the operation process of a low-voltage power grid, so that the comprehensive coverage of the low-voltage power distribution network cannot be performed, and the accuracy and the stability of the transformer area identification are influenced. More importantly, due to the working mode of carrier communication, the phenomena of common cable channel, common ground and common high voltage are easy to occur in the transmission process of adjacent transformers; and the signal interference of the communication base station is also a factor which can cause identification misjudgment, and can cause common high voltage crosstalk, common ground crosstalk and parallel transmission crosstalk of carrier signals.
From the actual operation on site, most of the current platform area identification devices adopt a PC (personal computer) mode and a slave mode as handheld terminals, are large in size, heavy and not easy to carry, adopt a host three-phase sending mode and adopt a slave receiving single-phase communication mode, and are low in testing speed; the result is inaccurate, but the price is high, and the function is single. Therefore, the research on a platform area identification technology which can improve the communication reliability and stability, realize the comprehensive coverage of a low-voltage platform area, and has the advantages of accurate, quick and visual result judgment, small volume, light weight, convenient carrying and low price is the development trend in the future.
Disclosure of Invention
The invention aims to overcome the problems of low accuracy and stability of district identification in the prior art, and provides a device and a method for detecting the connection relation between a user electric meter and a transformer.
The purpose of the invention can be realized by the following technical scheme:
a user electricity meter and transformer connection relation detection device comprises:
the voltage modulation part is arranged between the transformer outlet end of the transformer in the transformer area and a user line, and comprises a voltage modulation circuit and a controller, wherein the voltage modulation circuit comprises an anti-parallel diode and a bypass switch which are connected in parallel;
the user electric meter data acquisition part is connected with the user electric meter and is used for acquiring voltage data of the user electric meter;
and the user electric meter data analysis part is connected with the user electric meter data acquisition part and used for judging the transformer line relation to which the user electric meter belongs according to the voltage data.
Further, one transformer is provided for one of the voltage modulation sections.
Further, the bypass switch is a relay or a MOSFET.
Furthermore, the user electric meter data acquisition part is connected with the user electric meter in a wireless, communication cable or power line carrier communication mode.
Furthermore, the user electric meter data acquisition part comprises meter reading equipment and a database server.
Further, the user electricity meter data analysis section includes:
the modulation signal acquisition unit is used for extracting a real-time modulation signal by using a cross-correlation function according to the voltage data;
and the household variable relation identification unit is used for comparing the real-time modulation signal with a pre-stored modulation signal and identifying and obtaining the transformer line relation to which the user electric meter belongs.
The invention also provides a method for detecting the connection relation between the user electric meter and the transformer by adopting the detection device, which comprises the following steps:
the controller controls the switching state of the bypass switch according to a pre-stored modulation signal, and modulates the input voltage of the voltage modulation circuit to a set output voltage;
and collecting voltage data of each user electric meter, and judging and obtaining the transformer line relation of each user electric meter according to the voltage data and a prestored modulation signal.
Further, each zone transformer has an independent pre-stored modulation signal.
Further, the step of judging and obtaining the transformer line relationship to which each user electricity meter belongs according to the voltage data and the pre-stored modulation signal specifically includes:
and extracting a real-time modulation signal by using a cross-correlation function according to the voltage data, comparing the real-time modulation signal with a pre-stored modulation signal, and identifying and obtaining the transformer line relation to which the user ammeter belongs.
Further, the method further comprises:
and visually displaying the real-time modulation signal and a pre-stored modulation signal.
Compared with the prior art, the invention has the following beneficial effects:
1) the invention utilizes the voltage data to judge the line relation of the transformer to which the user ammeter belongs, and the judgment result is accurate and quick;
2) the voltage modulation circuit is formed by the anti-parallel diode and the bypass switch which are connected in parallel, the bypass switch can be controlled by the controller in real time, and the voltage modulation circuit is simple in structure, small in size, light in weight, convenient to carry and low in price;
3) according to the invention, each line adopts a unique modulation signal to modulate the line output voltage, and the modulation signal is used as line identification information, so that a judgment result can be quickly obtained;
4) the invention has the visualization function and the judgment result is visual.
Drawings
FIG. 1 is a schematic structural view of the present invention;
FIG. 2 is a schematic diagram of a voltage modulation circuit according to the present invention;
fig. 3 is a schematic diagram of an output voltage of the voltage modulation unit according to the present invention.
Detailed Description
The invention is described in detail below with reference to the figures and specific embodiments. The present embodiment is implemented on the premise of the technical solution of the present invention, and a detailed implementation manner and a specific operation process are given, but the scope of the present invention is not limited to the following embodiments.
As shown in fig. 1, the present embodiment provides a device for detecting a connection relationship between a user electric meter and a transformer, which includes a voltage modulation portion 2, a user electric meter data acquisition portion 5, and a user electric meter data analysis portion 6, wherein the voltage modulation portion 2 is installed between a line outlet end of a transformer 1 in a transformer area and a user line, the user line includes a user electric meter 3 and a user load 4, which are connected to each other, the user electric meter data acquisition portion 5 is connected to the user electric meter 3, and the user electric meter data analysis portion 6 is connected to the user electric meter data acquisition portion 5. The device detects the transformer corresponding to the user-side ammeter and a certain phase line of the transformer in a mode of disturbing the output voltage amplitude of the transformer.
One transformer 1 is provided with one voltage modulation part 2, so that each transformer and the user electric meter corresponding to the transformer have independent pre-stored modulation signals, as shown in fig. 3.
The voltage modulation unit 2 modulates the voltage output from the block transformer 1 to a predetermined amplitude. As shown in fig. 2, the voltage modulation section 2 includes a voltage modulation circuit including an anti-parallel diode 21 and a bypass switch 22 connected in parallel, and a controller that controls the switching state of the bypass switch 22. The bypass switch 22 may be a relay or a MOSFET, etc. When the bypass switch 22 is turned on, the voltage is transmitted normally, and the output voltage of the voltage modulation circuit is the same as the output voltage. When the bypass switch 22 is off, the output voltage of the voltage modulation circuit is lower than the input voltage due to the presence of a conducting voltage connection of the anti-parallel diode 21. Therefore, the state of the bypass switch is changed according to a certain rule, and the output voltage amplitude of the voltage modulation part can be changed regularly. By using this principle, information to be transmitted can be modulated on the output voltage of the voltage modulation unit. The voltage modulation section 2 modulates the line output voltage with a unique modulation signal so that the output line voltage of each transformer has line identification information.
The user electric meter data acquisition part 5 is used for acquiring and storing voltage data of a user electric meter at regular time. In this embodiment, the user electric meter data acquisition unit 5 is connected to the user electric meter 3 in a wireless manner, and the user electric meter data acquisition unit 5 includes a centralized meter reading device and a database server. The centralized meter reading equipment is arranged at the user side.
In some embodiments, the user meter data collecting part 5 may also be connected to the user meter 3 through a communication cable or a power line carrier communication manner.
The user electric meter data analysis part 6 judges the transformer line relation to which the user electric meter belongs according to the voltage data, and comprises the following steps: the modulation signal acquisition unit is used for reading the voltage data stored in the database server and extracting a real-time modulation signal by utilizing a cross-correlation function; and the household variable relation identification unit is used for comparing the real-time modulation signal with a pre-stored modulation signal and identifying and obtaining the transformer line relation to which the user electric meter belongs.
The working process of the device for detecting the connection relation between the user electric meter and the transformer comprises the following steps:
the controller controls the switching state of the bypass switch according to a pre-stored modulation signal, and modulates the input voltage of the voltage modulation circuit to a set output voltage;
collecting voltage data of each user electric meter, extracting a real-time modulation signal by using a cross-correlation function according to the voltage data, comparing the real-time modulation signal with a pre-stored modulation signal, and identifying and obtaining the line relation of a transformer to which the user electric meter belongs
In this embodiment, the method further includes: and visually displaying the real-time modulation signal and a pre-stored modulation signal.
The foregoing detailed description of the preferred embodiments of the invention has been presented. It should be understood that numerous modifications and variations could be devised by those skilled in the art in light of the present teachings without departing from the inventive concepts. Therefore, the technical solutions that can be obtained by a person skilled in the art through logic analysis, reasoning or limited experiments based on the prior art according to the concept of the present invention should be within the protection scope determined by the present invention.
Claims (10)
1. The utility model provides a user's ammeter and transformer relation detection device, its characterized in that includes:
the voltage modulation part is arranged between the transformer outlet end of the transformer in the transformer area and a user line, and comprises a voltage modulation circuit and a controller, wherein the voltage modulation circuit comprises an anti-parallel diode and a bypass switch which are connected in parallel;
the user electric meter data acquisition part is connected with the user electric meter and is used for acquiring voltage data of the user electric meter;
and the user electric meter data analysis part is connected with the user electric meter data acquisition part and used for judging the transformer line relation to which the user electric meter belongs according to the voltage data.
2. The apparatus of claim 1, wherein one of said voltage modulation sections is provided for one of said district transformers.
3. The apparatus as claimed in claim 1, wherein the bypass switch is a relay or a MOSFET.
4. The apparatus of claim 1, wherein the user meter data collection unit is connected to the user meter in a wireless, communication cable, or power line carrier communication manner.
5. The device for detecting the connection relationship between the consumer electric meter and the transformer as claimed in claim 1, wherein the data acquisition part of the consumer electric meter comprises a meter reading device and a database server.
6. The apparatus of claim 1, wherein the user meter data analysis unit comprises:
the modulation signal acquisition unit is used for extracting a real-time modulation signal by using a cross-correlation function according to the voltage data;
and the household variable relation identification unit is used for comparing the real-time modulation signal with a pre-stored modulation signal and identifying and obtaining the transformer line relation to which the user electric meter belongs.
7. A method for detecting the connection between a user meter and a transformer by using the detecting device as claimed in claim 1, comprising the steps of:
the controller controls the switching state of the bypass switch according to a pre-stored modulation signal, and modulates the input voltage of the voltage modulation circuit to a set output voltage;
and collecting voltage data of each user electric meter, and judging and obtaining the transformer line relation of each user electric meter according to the voltage data and a prestored modulation signal.
8. The method as claimed in claim 7, wherein each zone transformer has an independent pre-stored modulation signal.
9. The method for detecting the connection relationship between the user electric meters and the transformers according to claim 7, wherein the step of judging and obtaining the line relationship of the transformers to which the user electric meters belong according to the voltage data and the pre-stored modulation signals specifically comprises the steps of:
and extracting a real-time modulation signal by using a cross-correlation function according to the voltage data, comparing the real-time modulation signal with a pre-stored modulation signal, and identifying and obtaining the transformer line relation to which the user ammeter belongs.
10. The method of claim 9, wherein the method further comprises:
and visually displaying the real-time modulation signal and a pre-stored modulation signal.
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| CN112611997A (en) * | 2020-12-01 | 2021-04-06 | 国网河南省电力公司电力科学研究院 | Online verification method and system for hitching relation of platform area gateway table |
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