RU2720638C1 - Device for monitoring and diagnostics of high-voltage linear polymer insulators - Google Patents

Abstract

FIELD: electric power engineering.

SUBSTANCE: invention relates to electric power engineering and can be used for monitoring and diagnostics of high-voltage linear polymer insulators state on power transmission lines. Device for monitoring and diagnostics of high-voltage linear polymer insulators comprises means for measuring intensity of electric field along axis of high-voltage linear polymer insulator and transmission of data on level of intensity of electric field at sensor mounting point, temperature of the insulator, temperature and humidity of the air at the location of the insulators at the current moment of time to the monitoring and diagnostic center server. Above device contains electric field intensity sensors, each of which is located in the housing of silicone rubber with elements of their attachment to high-voltage polymer insulators. Each of the sensors consists of a capacitive power supply, which is a power take-off capacitor with plates arranged parallel to each other, a gap between which is filled with a dielectric layer, and an electronic unit. One of the capacitors of the capacitive power supply represents a metal plate, and the second cover plate is made in the form of a metal flat hollow body coated with a layer of silicone rubber, in which there is an electronic unit consisting of a power accumulator of periodic action, to which a controller is connected. Temperature sensor is connected to the controller input, and a radio transmitter with an antenna is connected to the output. Electric energy accumulator contains a diode bridge, the input of which is connected to the plates of the capacitive power supply source, and to its output the intermediate capacitor is connected in parallel, to which a storage capacitor is connected through the discharge element.

EFFECT: high quality of diagnosing high-voltage polymer insulators.

3 cl, 7 dwg

Description

Technical field

The invention relates to devices for monitoring and diagnosing the state of high-voltage linear polymer insulators on power lines and can be used in the electric power industry.

State of the art

In recent decades, polymer linear insulators have become widespread due to their excellent electrical performance in pollution conditions. They have high hydrophobicity, tracking resistance, erosion resistance. The insulator consists of a supporting fiberglass rod, a finned protective sheath made of silicone rubber around it and metal terminators. In developed countries, the number of polymer insulators in networks reaches 50%. However, they have one big minus is the lack of the ability to quickly identify a damaged linear polymer insulator.

After a short circuit (short circuit) and disconnection of the entire line, the damaged insulator cannot be detected. The suspension insulator usually does not have visible damage.

Currently, there are a variety of methods for monitoring the condition of polymer insulators, but they do not meet the criteria of simplicity, efficiency, and convenience.

Monitoring and diagnostics of the state of high-voltage suspended polymer insulation in Russia and around the world, mainly carried out periodically by inspections when bypassing the ground, or using aircraft. Both visual inspections and the use of special equipment (electron-optical flaw detectors and thermal imagers). By analyzing the images obtained in the visible, infrared (IR) and ultraviolet (UV) spectrum, a decision is made on the condition of the insulators (Rules for the technical operation of power plants and networks of the Russian Federation SO 153-34.20.501-2003, approved by Order of the Ministry of Energy of Russia dated 19.06.2003 N 229; “Scope and norms of testing electrical equipment”, approved and enforced by the Order of PJSC Rosseti dated May 29, 2017 No. 280r; “Methodological instructions for remote optical monitoring of insulation of overhead power lines and switchgears of alternating current voltage of 35-1150 kV, STO 56947007-29.240.003-2008, approved by the Deputy Chairman of the Management Board of JSC FGC UES VV Dorofeev, Minutes No. 4 of the meeting of the Standing Committee on the Normative and Technical Support of the Activities of JSC FGC UES of June _28_

However, this is fraught with many difficulties. It is impossible to conduct continuous monitoring of the condition of the insulators by such monitoring methods, which, in turn, does not allow to quickly determine the place of damage. The main destructive processes in the insulator occur at a time unfavorable for the examination: thunderstorm, rain, dew, and after drying the insulator can show quite acceptable results in the IR and UV ranges. Constant changes in temperature, humidity, wind speed, lightning and switching overvoltages in the network make it necessary to take into account changes when setting up flaw detection equipment, which affects the duration of the search for a defective insulator, the results of the read parameters and carries some probability of processing errors. The thermal radiation of destructive processes in the insulator is quite difficult to establish. This is due to the large distance from the insulator to the device, the small size of the heated surface, the usual strong winds at the height of operation of the insulators, and the low thermal conductivity of the silicone protective sheath. Measurements are preferably carried out in the dark or in cloudy weather. In the case of a short circuit and disconnection of the line, the IR and UV examination methods cannot be applied due to the absence of voltage in the line and the processes that cause these emissions.

Specialists in the inspection of equipment by the UVC method must have a high level of technical training, they must know:

device, principle of operation and main types of UV cameras;

design of the examined equipment and types of possible defects;

types and causes of discharge processes;

technogenic and climatic factors affecting the intensity of discharges;

possible sources of interference.

technology and physical foundations of thermal control (IR)

technology and physical fundamentals of visual and measuring control of electrical equipment

correctly document, interpret and evaluate the results of UV monitoring.

to draw up the results of the inspection with the issuance of an opinion (SDOS-10-2015 Regulation on the certification of personnel in the field of ultraviolet non-destructive testing // Adopted by the Bureau of the Supervisory Board dated 06.06.15 No. 74-BNS of the Scientific and Technical Center "Industrial Safety").

A device for remote diagnostics of the state of high-voltage insulators (patent RU 2597962 C1, IPC G01R 31/08, published September 20, 2016) is used in which an electro-optical sensor is used according to the value of the laser beam reflection coefficient from it, which is proportional to the electric field strength. In this case, the electro-optical sensor is graduated by introducing it into a calibrated alternating electric field. Then, for each type of reference high-voltage insulators that are to be diagnosed, average values of the intensity of alternating electric fields corresponding to the working high voltage and the limit boundaries of the gradients of the intensity of electric fields that do not create an electrical breakdown or overlap of insulators are determined during bench measurements. Next, an electro-optical sensor located on a dielectric rod and connected, through a polarizing discriminator and a fiber optic cable, to a laser emitter, as well as to a photodetector, is scanned along the surface of the reference high-voltage insulator, simultaneously recording the spatial position of the electro-optical sensor on the surface of the insulator and its corresponding electric field strength, measure the normal and tangential components of the gradients of the electric field strength. Then, the spatial distribution of elevated normal and tangential to the surface gradients of the electric field strength is compared using a specific computer program with the previously recorded distribution of the voltage values for the reference high-voltage insulator and the areas of possible internal breakdowns and surface overlap in the insulator are identified by highlighting the electric field strength gradients exceeding the level safe for the normal functioning of this type of high voltage support insulators.

The disadvantages of this device are:

- control of insulators is carried out periodically;

- Diagnostic work is carried out in manual mode by a specialist on existing electrical equipment;

- it is necessary to graduate the sensor in an alternating calibrated electric field;

- for each type of insulators, it is necessary to first determine the values of the distribution of electric field strength along its axis;

- it is necessary to register the spatial position of the sensor during measurements.

The closest analogue of the claimed technical solution is a tester of the Canadian company Positron Inc. (US patent 4760343, IPC G01R 29/12, published July 26, 1988), namely: a device for detecting defective insulators in an insulating column supporting an electrical conductor (cable) of a power line in which said column consists of series-connected insulators . The specified device contains: sensitive to the electric field means in the form of a probe of an electric field; means for directing and displacing said electric field probe along an axis parallel to the longitudinal axis of said column for performing electric field measurement at predetermined positions along the column; means for counting said insulators (when said electric field sensor is offset) and for locating said predefined positions to obtain electric field values; means for transmitting electric field values and position signals; means for receiving and recording the indicated number of insulators and the mentioned electric field values, as well as means for analyzing and correlating the said electric field values with the integrity state of the individual insulators making up the specified insulating column. Sensitive to the electric field means, made in the form of a probe, contains a pair of spaced apart electrodes, supported parallel to each other on the support frame of the probe. The electrodes of said probe are oriented substantially along a plane transverse to the longitudinal axis of the insulating column. The means for counting the insulators comprises a detector that is actuated to close when the outer rim of each insulator in said column is determined by a receiving element, whereby said electric field is measured. The transmission medium is a frequency transmitter for transmitting signals representing said measured electric field values and position signals. The moving means is an elongated insulated boom pivotally connected at one end to said guide frame, whereby the operator can shift said guide frame to said column by manipulating the opposite end of said boom.

Positron Inc Insulator Testers perceive and record the distribution of the electric field along the insulators, showing all wired defects in the insulator.

As a result of studies, it was found that changes in the distribution of the electric field occur near the defective part of the insulator of the high-voltage line under voltage. This dependence was confirmed not only in the laboratory conditions of many leading energy companies, but also during tens of thousands of practical tests using Positron equipment

Positron testers provide reliable and accurate results, unlike other test instruments, such as an ultraviolet or infrared detector, which are based on visual indications and can only detect very serious defects that are already obvious and go far beyond safety.

The method of measuring the electric field makes it possible to detect even very insignificant defects in insulators long before they create a real danger.

The disadvantage of this tester is the significant complexity in the diagnosis. Work is carried out with the participation of a person on an included power line. Measurements of this kind are performed selectively on those insulators that are identified as problematic according to visual and IR / UV observations. It is not possible to identify a defect located closer than 15 centimeters from the terminal. During measurements, the tester moves manually along the insulators using an insulating rod. The operator is located either on the tower or on the support beam.

Disclosure of invention

The technical result of the claimed invention is to improve the quality of diagnosis of high-voltage polymer insulators by constantly monitoring in real time the intensity of a sharply inhomogeneous electric field along the axis of high-voltage linear polymer insulators and timely informing about the onset of defects and their development in automatic mode.

The specified technical result is achieved by the fact that in the device for monitoring and diagnostics of high-voltage linear polymer insulators, containing means for measuring the electric field along the axis of the high-voltage linear polymer insulator, the temperature of the insulator, temperature and humidity in the region of the insulator, the location of the support and transmission of these data to the server of the monitoring and diagnostic center for analysis, according to the invention, this tool contains electric field strength sensors with elements for their attachment to high-voltage polymer insulators, each of which is located in a housing made of a dielectric, for example silicone rubber, and consists of a capacitive source power, which is a power take-off capacitor with plates parallel to each other, the gap between which is filled with a layer of a dielectric and an electronic unit; one of the plates of the capacitive power source is a metal plate, and the second plate is made in the form of a metal flat hollow body in which an electronic unit is located, consisting of a batch of electrical energy, to which a controller and a radio transmitter with an antenna are connected; moreover, the electric energy storage device contains a diode bridge, the input of which is connected to the plates of the capacitive power source, and an intermediate capacitor is connected to its output in parallel, to which a storage capacitor is connected through the discharge element. Moreover, a temperature sensor is connected to the controller input, and a radio transmitter is connected to its output.

On each support of the power line, electric field sensors with fasteners are located one on each high-voltage polymer insulator above the terminal supporting the phase wire and are attached to the central core of the insulator to ensure that the plates of the capacitive power source of the specified sensor are perpendicular to the axis of the insulator.

The place for installing the sensor was chosen on the basis that the observed electrical aging of polymer insulators most often originates under a protective shell at the triple border “terminal - fiberglass rod - air” from the high potential side (F. Schmuck, J. Seifert, I. Gutman, A. Pigini: "Assessment of the condition of overhead line composite insulators", Paris, CIGRE-2012, B2-214.).

In addition, the device is equipped with base stations with fastening elements for support for receiving data from electric field strength sensors, each of which contains a metal case in which a controller is connected, connected to a power source, a transceiver with transmitting and receiving antennas, read-only memory, GPS -module with antenna, temperature and humidity sensor. Moreover, each transmission line support has one base station receiving data from electric field strength sensors located on the insulators of said transmission line support. The base station supplements the data received from the electric field strength sensors with data on temperature and humidity at the current time, the coordinates of the location of the pylon, temporary storage and relay them through the programmed time intervals through the base stations located on other pylons in a given direction to the server of the monitoring and diagnostic center for saving and analysis.

Based on the information received from the electric field strength sensors and the base station of this support through other base stations to the server of the monitoring and diagnostic center, an analysis of the electric field changes at the sensor installation site is carried out taking into account climatic factors. According to the results of the analysis, the beginning and dynamics of the defect development are recorded and planning for the replacement of insulators on power lines is provided before an emergency occurs. The claimed device operates in an automated mode, does not require the participation of linear staff.

The device is illustrated by the following drawings.

In FIG. 1 is a schematic diagram of a device for monitoring and diagnosing high-voltage linear polymer insulators. In FIG. 2 shows the appearance of an electric field strength sensor. In FIG. Figure 3 shows the location of the electric field strength sensor on a high-voltage polymer insulator. In FIG. 4 is a diagram of an electric field strength sensor. In FIG. 5 is a diagram of a base station. In FIG. Figure 6 shows the distribution of electric field along the axis of the insulator on the surface of the shell for a “full” insulator (E) and a simplified model of the insulator (D) and the installation location of the sensor (Electric Field & Voltage Distribution Along Non-Ceramic Insulators. INMR. July 15, 2017. ) In FIG. Figure 7 shows a graph of the relative changes in the charge time of the drive obtained experimentally and a graph of the calculated potential difference induced on the sensor plates of the electric field in% of the initial values depending on the length (in mm) of the track (defect) in the insulator.

A device for monitoring and diagnosing high-voltage linear polymer insulators contains means for measuring the electric field along the axis of the high-voltage linear polymer insulator, insulator temperature, ambient temperature and humidity, and the location of the support for transmission to the monitoring and diagnostic center server for processing and analysis.

The specified tool contains sensors 1 of the electric field with their fastening elements (not shown in the drawings) to high-voltage polymer insulators 2, base stations 3 with their fastening elements to the supports 4 and the server of the monitoring and diagnostic center 5 located at the substation (Fig. 1, 3 )

Each of the sensors 1 of the electric field strength (Fig. 2, 4) is located in a housing 6 made of a dielectric, for example, silicone rubber, and consists of an electronic unit 7 and a capacitive power source 8, which is a power take-off capacitor with two plates 9, 10 spaced parallel to each other. The gap between the plates 9, 10 is filled with a dielectric layer 11. The cover 9 of the capacitive power supply 8 is a metal plate 12, and the cover 10 is made in the form of a metal flat hollow body 13. In the body 13 is an electronic unit 7, which consists of a periodic energy storage device 14, to which a controller 15 and a radio transmitter 16 s are connected antenna 17. A temperature sensor 18 is connected to the controller 15. The energy storage device 14 contains a diode bridge 19, the input of which is connected to the plates 9, 10 of the capacitive power source 8, and an intermediate capacitor 20 is connected to its output, to which an accumulative element 21 is connected capacitor 22.

Sensors 1 of the electric field with mounting elements are located on the traverses 23 (Fig. 3) of each support 4 of the power line, one on each high-voltage polymer insulator 2 (in zone "A" with a sharply inhomogeneous electric field, as shown in Fig. 3 and Fig. 6) above the terminal 24 supporting the phase wire 25 and attached to the central shaft of the insulator 2 to ensure that the plates 9, 10 of the capacitive power supply 8 of the indicated sensor 1 are located perpendicular to the axis of the insulator 2 in zone “A” with a sharply inhomogeneous electric field to ensure the functioning of the source power 8 and electronic unit 7.

Each of the base stations 3 consists of a metal case 26 with fastening elements to the support 4, in which are located (Fig. 5) a power supply 27, a controller 28 to the input of which a temperature and humidity sensor 29, a GPS module 30 are connected. To the inputs and outputs of the controller 28, a read-only memory 31 and a transceiver 32 are connected. An antenna 33 is connected to the GPS module 30. A receive antenna 34 and a transmit antenna 35 are connected to the transceiver 32.

Moreover, each pylon 4 of the power line has one base station 3, receiving data from the sensors 1 of the electric field located on the insulators 2 of the indicated pylon 4 of the power line.

A device for monitoring and diagnosis of high-voltage linear polymer insulators works as follows.

The sensor 1 is installed on the insulator 2 in the zone "A" exposure to a sharply inhomogeneous electric field (Fig. 3, 6).

When defects appear in the fiberglass core of the insulator 2 (in the form of moisture penetration and the formation of a track), the potential changes along the axis of the insulator 2 and the field strength changes in zone “A” of the sensor 1 of the electric field intensity of the device.

Due to the capacitive coupling between the electric field source and the plates 9, 10 of the capacitive power supply 8 (Fig. 2) of the sensor 1, different potentials are induced on these plates. In the drive 14 of the electronic unit 7 connected to the power supply, an alternating current arises which is rectified by the diode bridge 19 and charges the intermediate capacitor 20 (Fig. 4). As soon as the voltage across the capacitor 20 reaches the operating voltage of the discharge element 21, the latter opens and the storage capacitor 22 is charged. The charged storage capacitor 22 powers the controller 15, which generates a signal and transfers it to the base station 3 through the radio transmitter 16 (Fig. 1). When the voltage decreases, the discharge element 21 closes, the capacitors 20 and 22 are again sequentially charged and the process repeats.

The change in the electric field in the zone "A" of the sensor 1 on the insulator 2 (Fig. 6) is estimated by the change in the charging time of the capacitive energy storage device 14 from the capacitive power source 8. The charging time of the drive 14 is proportional to the electric field in the zone "A" of the sensor installation 1 on the insulator 2. Thus, the periodic storage electric energy storage device 14 provides the operation of the electric field intensity sensor 1 in a cyclic mode. The capacitances of the capacitors 20 and 22 are calculated so that the voltage 15 required for operation is on the controller 15 and the radio transmitter 16. The charging time of the drive 14 to a predetermined voltage depends on the magnitude of the electric field strength and changes as the defect develops in the insulator 2. When the voltage appears on the controller 15 and the radio transmitter 16, the controller 15 reads the operation counter from the non-volatile memory, increments it, writes the updated data to the memory and generates a code package consisting of sensor ID 1, a trip counter, an insulator temperature, and a checksum. The data generated by the controller 15 is transmitted by the radio transmitter 16 to the base station 3, located on the support 4, where it is supplemented by data on the temperature and humidity of the ambient air, the current time, the coordinates of the location of the support 4, are temporarily stored and relayed through the base station 3 through a predetermined time interval in relay mode, located on other supports 4 are transmitted in a predetermined direction to the server 5 of the monitoring and diagnostic center located at the substation for storage and analysis.

According to the data obtained, graphs are plotted (Fig. 7) of changes in the electric field (charge time of the capacitive energy storage 14) depending on the condition of the insulator 2 and climatic conditions, analyzing which one can identify both the appearance of the defect and its development in insulators 2, as well as the change in the level of pollution the specified insulator 2.

The proposed device for monitoring and diagnostics of insulators 2 allows simultaneously in the current time mode to control all insulators 2 on the power line and when deviations occur, make planned decisions on their replacement.

Thus, the technical result is achieved by analyzing the change in the charging time of the drive 14 of the sensor 1 between the responses, depending on the temperature of the insulator 2, the temperature and humidity in the place of installation of the insulator 2, you can judge the reasons for the change in the electric field in zone "A" installing the sensor 1 on the insulator 2 (Fig. 6). A change in the electric field in dry weather indicates the development of a conductive defect in the insulator 2 and the need to decide on its replacement before an emergency occurs. By changing the electric field in wet weather, the formation of a dew point on the surface of the insulator 2 or in the surrounding air, you can evaluate the level of contamination of the surface of the insulator 2.

Claims (3)

1. A device for monitoring and diagnostics of high-voltage linear polymer insulators, containing a means for measuring the electric field along the axis of the high-voltage linear polymer insulator and transmitting data on the level of electric field at the sensor location, insulator temperature, temperature and humidity at the location of the insulators in the current time to the server of the monitoring and diagnostic center, characterized in that the said tool contains electric field strength sensors with elements for their attachment to high-voltage polymer insulators, each of which is located in a housing made of a dielectric, and consists of a capacitive power source, which is a power take-off capacitor with plates parallel to each other, the gap between which is filled with a dielectric layer, and an electronic unit; one of the plates of the capacitive power source is a metal plate, and the second plate is made in the form of a metal flat hollow body, in which an electronic unit is located, consisting of a batch of electrical energy, to which the controller is connected; a temperature sensor is connected to the controller input, and a radio transmitter with an antenna is connected to the output; moreover, the electric energy storage device contains a diode bridge, the input of which is connected to the plates of the capacitive power source, and an intermediate capacitor is connected to its output in parallel, to which a storage capacitor is connected through the discharge element. 2. The device according to p. 1, characterized in that on each support of the power line, the electric field strength sensors with fasteners are located one on each high-voltage polymer insulator above the terminal supporting the phase wire and are attached to the central core of the insulator to ensure that the capacitive plates the power source of the specified sensor perpendicular to the axis of the insulator. 3. The device according to claim 1, characterized in that it is equipped with base stations for receiving data from electric field strength sensors, each of which contains a controller connected to a power source, a transceiver with transmitting and receiving antennas, read-only memory, a GPS module with an antenna, a temperature and humidity sensor, each transmission line support having one base station receiving data from electric field strength sensors located on insulators of said transmission line support.

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