CN106526294A - Over-voltage monitoring system and monitoring method for transmission line - Google Patents

Abstract

The invention relates to a transmission line overvoltage monitoring system and monitoring method, including: an overvoltage monitoring device, a background data processing device, a high-voltage arm capacitor and a low-voltage arm capacitor connected in series, wherein: the high-voltage arm capacitor includes several ceramic capacitors connected in series Insulator, one end of the high-voltage arm capacitor is electrically connected to the transmission line to be tested, and the other end is electrically connected to one end of the low-voltage arm capacitor; the low-voltage arm capacitor includes a ceramic capacitor insulator, and the other end of the low-voltage arm capacitor is grounded through the tower body; overvoltage monitoring device Installed on the tower body, the input end of the overvoltage monitoring device is electrically connected to the two ends of the low-voltage arm capacitor; the overvoltage monitoring device is communicatively connected with the background data processing device. Taking advantage of the advantages of high insulation strength, good mechanical properties and low price of ceramic capacitor insulators, it replaces the existing insulators or directly hangs on the transmission line, monitors the overvoltage of the transmission line to be tested in real time, and records the overvoltage data completely and accurately.

Description

A transmission line overvoltage monitoring system and monitoring method

technical field

The invention relates to the technical field of power system overvoltage monitoring, in particular to a transmission line overvoltage monitoring system and monitoring method.

Background technique

In the power system, monitoring the overvoltage of transmission lines is of great significance for obtaining real overvoltage data of transmission lines, analyzing overvoltage accidents, improving grid insulation coordination, improving lightning protection measures for overhead lines, and ensuring safe operation of power systems.

Overvoltage monitoring systems are generally divided into contact overvoltage monitoring systems and non-contact overvoltage monitoring systems. In the current power system, the commonly used overvoltage monitoring system is the contact overvoltage monitoring system. The contact overvoltage monitoring system is to install a capacitive voltage divider in the substation or on the transmission line, obtain the overvoltage signal through the capacitive voltage divider, and transmit the overvoltage signal to the data acquisition device through the coaxial cable.

However, for ultra-high voltage transmission lines and distribution network transmission lines, on the one hand, the installation of capacitive voltage dividers is costly and increases the workload of operation and maintenance; Operational risks, resulting in inaccurate monitoring results and other problems.

Contents of the invention

In order to overcome the problems existing in the related technologies, the present invention provides a transmission line overvoltage monitoring system and monitoring method.

According to the first aspect of the embodiments of the present invention, there is provided a power transmission line overvoltage monitoring system, including: an overvoltage monitoring device, a background data processing device, a high-voltage arm capacitor and a low-voltage arm capacitor connected in series, wherein:

The high-voltage arm capacitor includes a number of ceramic capacitor insulators connected in series, one end of the high-voltage arm capacitor is electrically connected to the transmission line to be tested, and the other end is electrically connected to one end of the low-voltage arm capacitor;

The low-voltage arm capacitor includes a ceramic capacitor insulator, and the other end of the low-voltage arm capacitor is grounded through the tower body;

The overvoltage monitoring device is arranged on the tower body, and the input end of the overvoltage monitoring device is electrically connected to both ends of the low-voltage arm capacitor;

The overvoltage monitoring device is communicatively connected with the background data processing device.

Preferably, a high-voltage ceramic capacitor is arranged inside the ceramic capacitor insulator.

Preferably, the overvoltage device includes a power-taking transformer and a data collection, processing and transmission device, wherein,

One end of the primary winding of the power-taking transformer is connected to one end of the low-voltage arm capacitor, and the other end is grounded; one end of the secondary winding of the power-taking transformer is electrically connected to the input end of the data collection, processing and transmission device, and the other end is connected to the ground. Grounding; the signal input end of the data acquisition processing and transmission device is electrically connected to one end of the low-voltage arm capacitor through a signal transmission line.

Preferably, the data collection processing and transmission device includes a data collection processor and a first wireless transmission device electrically connected to each other, and the signal input end of the data collection processor is connected to one end of the low-voltage arm capacitor through a signal transmission line.

Preferably, the background data processing device includes a background data processor and a second wireless transmission device matched with the first wireless transmission device.

According to the second aspect of the embodiments of the present invention, a transmission line overvoltage monitoring method is provided, including:

S001: Real-time monitoring of the phase voltage of the transmission line to be tested;

S002: Determine whether the phase voltage is an overvoltage; if so, execute step S003;

S003: Record the phase voltage data for 100ms;

S004: Determine whether the voltage amplitude in the phase voltage data has changed; if so, execute step S005; if not, return to step S003, and continue to record the phase voltage data for 100 ms;

S005: Stop recording, and send the data to the background data processing device.

The technical solutions provided by the embodiments of the present invention may include the following beneficial effects:

A power transmission line overvoltage monitoring system provided by an embodiment of the present invention includes: an overvoltage monitoring device, a background data processing device, a high-voltage arm capacitor and a low-voltage arm capacitor connected in series, wherein: the high-voltage arm capacitor includes several series-connected ceramics A capacitor insulator, one end of the high-voltage arm capacitor is electrically connected to the transmission line to be tested, and the other end is electrically connected to one end of the low-voltage arm capacitor; the low-voltage arm capacitor includes a ceramic capacitor insulator, and the other end of the low-voltage arm capacitor Grounding through the tower body; the overvoltage monitoring device is arranged on the tower body, and the input end of the overvoltage monitoring device is electrically connected to the two ends of the low-voltage arm capacitor; the overvoltage monitoring device is connected with the background data processing Device communication connection. Taking advantage of the advantages of ceramic capacitor insulators such as high insulation strength, good mechanical properties, and low price, it replaces existing insulators or directly hangs on the transmission line. At the same time, it serves as a voltage dividing system to monitor the overvoltage of the transmission line to be tested in real time and record the overvoltage data completely and accurately. , so as to judge the type of overvoltage, which can provide a scientific basis for the rapid response of the overvoltage suppression action of the power system and the formulation of the suppression strategy, and provide an effective solution for the overvoltage monitoring of the power system transmission line. At the same time, it can be used for lightning arrester status monitoring, fault location and line selection of transmission lines; it is of great significance to guide the fault maintenance and fault finding of power system equipment.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention.

Description of drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and together with the description serve to explain the principles of the invention.

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, for those of ordinary skill in the art, In other words, other drawings can also be obtained from these drawings without paying creative labor.

Fig. 1 is a schematic structural diagram of a transmission line overvoltage monitoring system provided by an embodiment of the present invention;

2 is a schematic structural diagram of an equivalent circuit of a transmission line overvoltage monitoring system provided by an embodiment of the present invention;

Fig. 3 is a schematic flow chart of a transmission line overvoltage monitoring method provided by an embodiment of the present invention;

In Figure 1-3, the symbols represent: 1-overvoltage monitoring device, 11-power transformer, 12-data acquisition processing and transmission device, 13-signal transmission line, 2-background data processing device, 3-ceramic capacitor insulator, C1-high voltage arm capacitor, C2-low voltage arm capacitor.

detailed description

Reference will now be made in detail to the exemplary embodiments, examples of which are illustrated in the accompanying drawings. When the following description refers to the accompanying drawings, the same numerals in different drawings refer to the same or similar elements unless otherwise indicated. The implementations described in the following exemplary examples do not represent all implementations consistent with the present invention. Rather, they are merely examples of apparatuses and methods consistent with aspects of the invention as recited in the appended claims.

An embodiment of the present invention provides an overvoltage monitoring system for a transmission line, as shown in FIG. 1 and FIG. 2 , including: an overvoltage monitoring device 1 , a background data processing device 2 , and a high-voltage arm capacitor C1 and a low-voltage arm capacitor C2 connected in series.

One end of the high-voltage arm capacitor C1 is electrically connected to the transmission line to be tested, and the other end is electrically connected to one end of the low-voltage arm capacitor C2, and the other end of the low-voltage arm capacitor C2 is grounded through the tower body.

As shown in FIG. 1 , the high voltage arm capacitor C1 includes several ceramic capacitor insulators 3 connected in series, and the low voltage arm capacitor C2 includes a ceramic capacitor insulator 3 . In the embodiment of the present invention, the high-voltage arm capacitor C1 composed of several ceramic capacitor insulators 3 in series and the low-voltage arm capacitor C2 composed of a ceramic capacitor insulator 3 form a voltage dividing system, which can be connected with power transmission Lines and towers are directly connected or directly replace transmission line insulators. In the specific implementation process, the high-voltage arm capacitor C1 composed of several ceramic capacitor insulators 3 in series and the low-voltage arm capacitor C2 composed of a ceramic capacitor insulator 3 form a voltage dividing system with a voltage dividing ratio of 500-3000. Any value between 500-3000 can be selected by the user according to the actual situation.

The ceramic capacitor insulator 3 is provided with a high-voltage ceramic capacitor inside. The high-voltage ceramic capacitor has the characteristics of high dielectric strength, small size, and good frequency characteristics. This feature can be used to package it inside the insulating pillar or manufacture it into various types of high dielectric strength The ceramic capacitor insulator of the transmission line is directly connected with the transmission line to form a voltage division system to realize overvoltage monitoring and online energy harvesting of the power system. In the specific implementation process, the ceramic capacitor insulator 3 includes one or more of pin-type ceramic capacitor insulators, column-type ceramic capacitor insulators, suspension ceramic capacitor insulators, butterfly-type ceramic capacitor insulators, and porcelain cross-arm ceramic capacitor insulators. The combination.

Ceramic capacitor insulators are used to form a voltage division system that is directly connected to the transmission line. The voltage division system also functions as a power collector and a voltage divider. Although the capacitance of ceramic capacitor insulators will change slightly with temperature changes, it fully meets the requirements for overvoltage monitoring of transmission lines. , can be installed in large quantities on transmission lines to solve the problem of line overvoltage monitoring, and provide real data for the study of transmission line overvoltage and insulation coordination and overvoltage propagation characteristics.

The overvoltage monitoring device 1 is arranged on the tower body, the input terminal of the overvoltage monitoring device 1 is electrically connected to the two ends of the low-voltage arm capacitor C2, and the overvoltage monitoring device 1 and the background data processing device 2 communication connection. The overvoltage monitoring device 1 is used to detect the overvoltage of the transmission line to be tested, and send the overvoltage data of the transmission line to be tested to the background data processing device 2 .

In the embodiment of the present invention, the overvoltage device 1 includes a power-taking transformer 11 and a data collection, processing and transmission device 12 .

One end of the primary winding of the power-taking transformer 11 is connected to one end of the low-voltage arm capacitor C2, and the other end is grounded, and one end of the secondary winding of the power-taking transformer 11 is electrically connected to the input end of the data acquisition processing and transmission device 12 connection, and the other end to ground. The power transformer converts the high-voltage alternating current obtained by the voltage dividing system into low-voltage direct current, and the low-voltage direct current is used to supply power to the data collection processing and transmission device 12, so that the data collection processing and transmission device 12 does not need to Equipped with power supply.

The signal input end of the data acquisition processing and transmission device 12 is electrically connected to one end of the low-voltage arm capacitor C2 through a signal transmission line 13 . In a specific implementation process, the signal transmission line 13 includes a coaxial cable, and the coaxial cable contains an internal resistance R, as shown in FIG. 2 , to prevent oscillation from affecting the accuracy of the test results.

In the embodiment of the present invention, the data acquisition processing and transmission device 12 includes a data acquisition processor and a first wireless transmission device electrically connected to each other, and the signal input end of the data acquisition processor communicates with the low-voltage One end of the arm capacitor C2 is electrically connected. The data collection processor is used to collect data, and the first wireless transmission device is used to send the data collected by the data collection processor to the background data processing device 2 .

The background data processing device 2 includes a background data processor and a second wireless transmission device matched with the first wireless transmission device. The second wireless transmission device is configured to receive data sent by the first wireless transmission device, and the background data processor processes the acquired data.

In a specific implementation process, the first wireless transmission device and the second wireless transmission device include mutually matching GPRS transmission devices.

A power transmission line overvoltage monitoring system provided by an embodiment of the present invention includes: an overvoltage monitoring device, a background data processing device, a high-voltage arm capacitor and a low-voltage arm capacitor connected in series, wherein: the high-voltage arm capacitor includes several series-connected ceramics A capacitor insulator, one end of the high-voltage arm capacitor is electrically connected to the transmission line to be tested, and the other end is electrically connected to one end of the low-voltage arm capacitor; the low-voltage arm capacitor includes a ceramic capacitor insulator, and the other end of the low-voltage arm capacitor Grounding through the tower body; the overvoltage monitoring device is arranged on the tower body, and the input end of the overvoltage monitoring device is electrically connected to the two ends of the low-voltage arm capacitor; the overvoltage monitoring device is connected with the background data processing Device communication connection. Taking advantage of the advantages of ceramic capacitor insulators such as high insulation strength, good mechanical properties, and low price, it replaces existing insulators or directly hangs on the transmission line. At the same time, it serves as a voltage dividing system to monitor the overvoltage of the transmission line to be tested in real time and record the overvoltage data completely and accurately. , so as to judge the type of overvoltage, which can provide a scientific basis for the rapid response of the overvoltage suppression action of the power system and the formulation of the suppression strategy, and provide an effective solution for the overvoltage monitoring of the power system transmission line. At the same time, it can be used for lightning arrester status monitoring, fault location and line selection of transmission lines; it is of great significance to guide the fault maintenance and fault finding of power system equipment.

Based on the same technical concept, an embodiment of the present invention also provides a transmission line overvoltage monitoring method, see Figure 3, including:

S001: Monitor the phase voltage of the transmission line to be tested in real time.

Connect the overvoltage monitoring device to both ends of the low-voltage arm capacitor C2, and install it on the steel tower body of the transmission line to be tested to monitor the phase voltage of the transmission line to be tested.

S002: Determine whether the phase voltage is an overvoltage. If yes, execute step S003.

When the system is running normally, the voltage detected by the overvoltage monitoring device is the phase voltage of the system When the phase voltage is detected as or when it is detected that the phase voltage contains a high-frequency signal of 500Hz to 2kHz, the phase voltage is an overvoltage. When the phase voltage is an overvoltage, step S003 is performed.

S003: Record the phase voltage data for 100ms.

Start the data acquisition processor and record the phase voltage data for 100ms.

S004: Determine whether the voltage amplitude in the phase voltage data has changed. If yes, execute step S005; if no, return to step S003, and continue to record phase voltage data for 100 ms.

S005: Stop recording, and send the data to the background data processing device.

When the recording is stopped, the data collected by the data collection processor is sent to the background computer processing system through the first wireless transmission device. This method can completely and accurately record overvoltage data, thereby judging the type of overvoltage, can provide a scientific basis for the rapid response of the power system overvoltage suppression action and the formulation of suppression strategies, and provide an effective solution for the overvoltage monitoring of the power system transmission line . At the same time, it can be used for lightning arrester status monitoring, fault location and line selection of transmission lines; it is of great significance to guide the fault maintenance and fault finding of power system equipment.

Other embodiments of the invention will be readily apparent to those skilled in the art from consideration of the specification and practice of the invention disclosure herein. This application is intended to cover any modification, use or adaptation of the present invention, these modifications, uses or adaptations follow the general principles of the present invention and include common knowledge or conventional technical means in the technical field not disclosed in the present invention . The specification and examples are to be considered exemplary only, with a true scope and spirit of the invention being indicated by the following claims.

It should be understood that the present invention is not limited to the precise constructions which have been described above and shown in the accompanying drawings, and various modifications and changes may be made without departing from the scope thereof. The scope of the invention is limited only by the appended claims.

Claims (6)

1. A power transmission line overvoltage monitoring system is characterized in that, comprising: overvoltage monitoring device (1), background data processing device (2), high-voltage arm capacitance (C1) and low-voltage arm capacitance (C2) connected in series, in: The high-voltage arm capacitor (C1) includes a number of ceramic capacitor insulators (3) connected in series, one end of the high-voltage arm capacitor (C1) is electrically connected to the transmission line to be tested, and the other end is connected to one end of the low-voltage arm capacitor (C2). electrical connection; The low-voltage arm capacitor (C2) includes a ceramic capacitor insulator (3), and the other end of the low-voltage arm capacitor (C2) is grounded through the tower body; The overvoltage monitoring device (1) is arranged on the tower body, and the input end of the overvoltage monitoring device (1) is electrically connected to both ends of the low-voltage arm capacitor (C2); The overvoltage monitoring device (1) is communicatively connected with the background data processing device (2). 2. The transmission line overvoltage monitoring system according to claim 1, characterized in that a high-voltage ceramic capacitor is arranged inside the ceramic capacitor insulator (3). 3. The transmission line overvoltage monitoring system according to claim 1, characterized in that, the overvoltage device (1) comprises a power transformer (11) and a data acquisition processing and transmission device (12), wherein, One end of the primary winding of the power-taking transformer (11) is connected to one end of the low-voltage arm capacitor (C2), and the other end is grounded, and one end of the secondary winding of the power-taking transformer (11) is connected to the data acquisition, processing and transmission The input end of the device (12) is electrically connected, and the other end is grounded; the signal input end of the data acquisition processing and transmission device (12) is electrically connected to one end of the low-voltage arm capacitor (C2) through a signal transmission line (13). 4. transmission line overvoltage monitoring system according to claim 3, is characterized in that, described data collection process and transmission device (12) comprise the data collection processor and the first wireless transmission device that are electrically connected to each other, and described data The signal input end of the acquisition processor is connected with one end of the low-voltage arm capacitor (C2) through a signal transmission line (13). 5. The transmission line overvoltage monitoring system according to claim 4, characterized in that, the background data processing device (2) comprises a background data processor and a second wireless transmission device matched with the first wireless transmission device transmission device. 6. A transmission line overvoltage monitoring method, characterized in that, comprising: S001: Real-time monitoring of the phase voltage of the transmission line to be tested; S002: Determine whether the phase voltage is an overvoltage; if so, execute step S003; S003: Record the phase voltage data for 100ms; S004: Determine whether the voltage amplitude in the phase voltage data has changed; if so, execute step S005; if not, return to step S003, and continue to record the phase voltage data for 100 ms; S005: Stop recording, and send the data to the background data processing device.