WO2010095398A1

WO2010095398A1 - Corona discharge detection system by means of artificial satellite images and image analysis device thereof

Info

Publication number: WO2010095398A1
Application number: PCT/JP2010/000832
Authority: WO
Inventors: 園部武雄; 鈴木康介
Original assignee: 一般社団法人つくば電磁界研究機構
Priority date: 2009-02-20
Filing date: 2010-02-10
Publication date: 2010-08-26
Also published as: JP2012095367A

Abstract

Provided is a corona discharge detection system and image analysis device thereof which monitors an electric power system distributed over a wide area, identifies equipment which is generating corona discharge, and provides information for appropriate electric power system inspection. The corona discharge detection system is equipped with an artificial satellite (110) which images an electric power system network (152) on the surface of the earth (150) and which possesses a device which transmits imaged images via a communication link, a corona discharge detection means which can detect from the artificial satellite (110) the locations in the electric power system network (152) where corona discharge is generated, and an image analysis device (140) which receives the images transmitted by the artificial satellite (110) and analyzes the information on the locations where corona discharge is generated as detected by the corona discharge detection means.

Description

Corona discharge detection system using satellite image and image analysis device

The present invention relates to a corona discharge detection system based on an artificial satellite image and an image analysis apparatus therefor, and more particularly to a corona discharge detection system that analyzes a satellite image and identifies a location where a corona discharge has occurred in a transmission line network.

FIG. 6 is a basic configuration diagram of a large-scale power system. As shown in FIG. 6, a large-scale power system is basically composed of facilities having functions of generating, transporting and distributing power. In other words, the power system system has a distribution facility consisting of a power plant and transmission lines, substations, distribution lines, etc. as its main components, and power supply / communication equipment corresponding to the neural system for maintaining normal operating conditions, protection / A control device is provided (see Non-Patent Document 1, etc.).

As shown in FIG. 6, the power system includes power plants G1, G2,..., Gn, power transmission lines H1, H2,..., Hk, substations T1, T2,. , Cj, transmission lines D1, D2,..., Dh to the distribution system, and distribution systems U1, U2,. The power plants G1, G2,..., Gn are composed of nuclear power plants, hydroelectric power plants, thermal power plants, and the like. These power plants will be built away from the large cities that are in demand because of the difficulty of location. The generated electric power is transformed into a high voltage (500 KV, 275 KV, 220 KV, 187 KV, etc.) in order to reduce transmission loss, and is transmitted to the suburbs of large cities by power transmission lines H1, H2,. The electric power transmitted to the suburbs of large cities is integrally linked by substations T1, T2,..., Tm, and transmission lines C1, C2,. This is to eliminate the imbalance in supply and demand in each region and to supply economically stable power by integrating with various power sources in the system. The integrated power is transformed into a low voltage (154 KV to 22 KV) via the substations T1, T2,..., Tm, and the distribution system at the transmission lines D1, D2,. Power is transmitted to U1, U2,..., Ua and supplied to each consumer.

Electric power system systems have been studied for many years, and a stable supply of electric power has become an important foundation for today's civilized society. Research has also been conducted on corona discharge that occurs when power is transmitted and distributed at a high voltage. In practical power transmission and distribution systems, consideration is given to preventing corona discharge from occurring under normal weather conditions.

In addition, the insulators of electric power facilities ensure safety against ground faults by determining the number and the number of insulators on the assumption of the amount of salt from the coast according to the installation location.

When flying salt adheres to the insulator device and accumulates fouling, discharge of streamers (air corona) and creeping corona tends to be induced on the surface of the insulator device, and in the worst case, a local arc is generated and connected to the whole series. Insulation failure may occur and lead to ground fault.

For this reason, it is necessary to monitor the amount of salt adhering to the insulator device. Access to high-voltage wires and work at high places are dangerous, and many insulators need to be inspected, which requires a lot of personnel and time. In particular, when a typhoon strikes and approaches, the amount of incoming salt increases over a wide area due to strong winds, so it is necessary to concentrate on the inspection work in a short time. Since work is temporarily congested, the development of efficient inspection work methods has been sought.

On the other hand, when the surface of the transmission line deteriorates due to long-term use, corona discharge occurs due to weather conditions. Further, corona discharge is characterized in that the electric field voltage is lowered when the discharge starts, and it lasts for a long time.

When corona discharge occurs from electrical equipment such as wires and insulators to which high voltage is applied, noise and radio wave interference and ultraviolet rays generated by corona discharge not only affect the living environment but also hinder the efficiency of power transportation. To do. Prevention and reduction of such corona discharge is an important issue for electric power companies.

Corona discharge is a discharge phenomenon induced by a strong electric field in the vicinity of the surface of a high-voltage power applying body such as an electric wire or insulator, and generates electromagnetic waves including ultraviolet rays in a wide frequency band and generates sound waves.

Taking advantage of these properties, observations using radio wave receivers or ultrasonic detectors and photographing with a visible camera have been performed. In conventional ultrasonic detection methods, it is difficult to identify the location where the corona discharge occurs, and in the method using a visible camera, the light from the sun is strong during the day and the location is not visible. there were.

The inventor has proposed to detect the occurrence of corona discharge in a power transmission line by installing an ultraviolet detection element in the vicinity of a person's residence (see Patent Document 1, etc.).

In addition, proposals have been made that can quantitatively determine the degree of contamination / defects in electrical equipment and their extent (see Patent Document 2, etc.).

WO2005 / 043708 JP 2006-10365 A

Non-Patent Document 1: The Institute of Electrical Engineers of Japan "Electrical Engineering Handbook 6th Edition"
485 to 486 pages, 1005 to 1023 pages, 1225 to 1226 pages.
Non-Patent Document 2: The Institute of Electrical Engineers of Japan, “Ionized Gas Theory”, pages 28-51, pages 103-114.

However, the power system is distributed over a very wide range. It is very difficult to monitor all the power facilities that constitute the power system. It was also difficult to monitor where and when corona discharge occurred during the entire operation of the power system.

It is an object of the present invention to provide a corona discharge detection system that monitors power facilities and the like that are widely distributed, identifies facilities that generate corona discharge, and provides information for appropriately performing power facility inspections. To do.

In order to solve the above-described problems, the inventors have intensively studied and, as a result, paid attention to the usefulness of analyzing an image transmitted from an artificial satellite, and have completed the following invention.

(1) An artificial satellite having a device for photographing a power facility network on the surface of the earth and transmitting the captured image through a communication line, and a corona discharge capable of identifying from the artificial satellite where the corona discharge has occurred in the power facility network A corona discharge detection system comprising: a detection unit; and an image analysis device that receives and analyzes an image transmitted from the artificial satellite for information on a location where the corona discharge specified by the corona discharge detection unit occurs.

According to the invention described in (1), the power equipment network on the surface of the earth is photographed by an artificial satellite, and the photographed image is transmitted through a communication line. The location where the corona discharge occurs in the power equipment network can be identified from the artificial satellite by the corona discharge detection means. Information on the location where the corona discharge specified by the corona discharge detection means is transmitted from the artificial satellite as part of the image information. By receiving the image transmitted from the artificial satellite and analyzing it by the image analysis means, it is possible to identify in which power facility the corona discharge is detected.

As mentioned above, the power equipment network spans a wide area, and it is very difficult to always observe all areas. Since various types of earth observation satellites are currently operating and the return cycle is from one day to several days, artificial satellites can monitor a power facility network in a wide area in a short time.

On the other hand, ultraviolet rays due to corona discharge are generated because the insulation is partially destroyed in the atmosphere. In many cases, the dielectric breakdown causes separation of electrons and cations, which are accelerated by high voltage and collide with molecules in the atmosphere to emit ultraviolet rays. The phenomenon may occur in a very fine part.

In the image analysis by the earth observation satellite that is currently put into practical use, since the resolution is about 0.5 m, it is difficult to directly detect the corona discharge. Therefore, corona discharge detection means is provided to detect corona discharge indirectly. Various types of corona discharge detection means can be employed as described below.

In addition, the ultraviolet rays generated by the corona discharge according to the present invention are UVC and have a wavelength of 195 nm to 280 nm. This is because ultraviolet rays derived from sunlight are blocked by the ozone layer or the like and do not reach the surface of the earth, so that ultraviolet rays caused by corona discharge can be distinguished from ultraviolet rays caused by sunlight.

(2) The corona discharge detection system according to (1), wherein the corona detection means is coated with a paint that emits fluorescence or phosphorescence when the power equipment is irradiated with ultraviolet rays generated by corona discharge.

(3) The corona discharge detection system according to (1), wherein the corona detection means includes an appliance that emits fluorescence or phosphorescence when the power equipment is irradiated with ultraviolet rays generated by corona discharge.

The invention described in (2) is a corona detection means in which a coating that emits fluorescence or phosphorescence is applied when the power equipment is irradiated with ultraviolet rays generated by corona discharge. The invention described in (3) An instrument that emits fluorescence or phosphorescence when attached with ultraviolet rays generated by electric discharge is attached.

As a paint that emits fluorescence when irradiated with ultraviolet rays generated by corona discharge, it may emit white light such as calcium halophosphate and calcium zinc phosphate used in fluorescent lamps. Eurobium-activated yttrium oxide having a fluorescent color of orange-red or magnesium fluoride germanate having a fluorescent color of deep red is preferable, but is not limited thereto. Further, for example, benzophenone can be used as the phosphorescent paint. The object to be applied is preferably a transmission tower, insulator, substation equipment, etc. that can secure a size that can be identified from an artificial satellite and that may cause corona discharge.

A device that emits fluorescence or phosphorescence when irradiated with ultraviolet rays generated by corona discharge is attached to the power facility with a configuration that does not supply power, for example, a device that has substantially the same appearance as a commercially available fluorescent lamp. It is economical to be a thing. A fluorescent tube coated with europium-activated yttrium oxide whose fluorescent color is orange-red or magnesium fluoride germanate whose fluorescent color is deep red is desirable so that it can be distinguished from other light when observed at night. It is not limited to this. It is desirable to make a specific shape of the fluorescent tube by combining a plurality of ring-shaped and rod-shaped tubes so that they can be easily identified from an artificial satellite.

(4) The corona discharge detection system according to (1), wherein the corona detection means is applied with a paint that changes color when the power equipment is irradiated with ultraviolet rays generated by corona discharge.
(5) The corona discharge detection system according to (1), wherein the corona detection means is a power facility coated with a photocatalyst.

(6) The corona discharge detection system according to (5), wherein the photocatalyst reacts with ultraviolet rays generated by corona discharge.

The inventions described in (4) to (6) are obtained by applying a paint that changes color when the power equipment is irradiated with ultraviolet rays generated by corona discharge. Since corona discharge often occurs when humidity is high, it is often impossible to observe from an artificial satellite because it is blocked by clouds. If a coating with a coating that changes color when irradiated with ultraviolet rays is used, corona discharge often occurs and the location to be maintained can be specified.

Also, the corona detection means is a power facility coated with a photocatalyst. When the photocatalyst is coated on the electric power equipment, the spot exposed to the light is removed due to the self-cleaning effect of the photocatalyst, so that it is possible to grasp the place where the light is surely received from a distance.

Technology has been developed for photocatalysts to react with visible light. The photocatalyst that reacts with visible light has an effect of preventing the occurrence of corona discharge by applying contamination to an insulator or the like, so that a portion contaminated by salt damage is cleaned.

On the other hand, titanium oxide (TiO ₂ ), which is often used for photocatalysts, produces a photocatalytic effect with so-called black light which is ultraviolet light of 410 nm or less. Research has been done on imparting visible light responsiveness of titanium oxide by doping various transition metals so that it can react even with visible light. See page 14 of the company).

In the present invention, it is necessary to distinguish between the ultraviolet rays caused by corona discharge observed from an artificial satellite and the ultraviolet rays caused by sunlight, which have been stained and discolored. Therefore, by using a photocatalyst that reacts with ultraviolet rays generated by corona discharge, if the contamination is removed by ultraviolet rays due to corona discharge, the difference can be detected by detecting the difference. As a photocatalyst that reacts with ultraviolet rays generated by corona discharge, a photocatalyst having a band gap from a valence band to a conduction band of 3.0 eV or more is desirable. Titanium oxide (TiO ₂ ) is specifically desirable, but is not limited thereto.

(7) The corona discharge detection system according to (1), wherein the corona detection means has planted a plant that changes color when irradiated with ultraviolet rays generated by corona discharge, in the vicinity of the power equipment network.

In the invention described in (7), a plant that changes color when irradiated with ultraviolet rays generated by corona discharge is planted in the vicinity of the power equipment network, and it is detected from an image from an artificial satellite that the plant has changed color. Detect what is happening.

Since there is a land owned by a power company near the power equipment network, a plant that changes color when irradiated with ultraviolet rays generated by corona discharge is planted on the land, and the plant has changed color from the satellite. It can be detected with an image. Plants are also related to the climate where the power equipment network is located, but research on UV-resistant plants is currently underway. By planting a mixture of B-region UV-resistant displacement plants and other plants, It can be detected from a satellite (see JP 2007-228922 A).

(8) An image analysis device used in a corona discharge detection system based on an artificial satellite image, the artificial satellite having a device for photographing a power facility network on the surface of the earth and transmitting the photographed image through a communication line, and the power facility Corona discharge detection means that can identify from the satellite where the corona discharge has occurred on the network, and an image transmitted from the artificial satellite that receives information on the location of the corona discharge identified by the corona discharge detection means An image analysis device that performs analysis.

The invention described in (8) is an image analysis device used for a corona discharge detection system based on an artificial satellite image. By using the image analysis apparatus of the present invention for the image analysis apparatuses (1) to (7), the same effects as described above can be exhibited.

According to the present invention, the power equipment network extends over a wide area, and it is very difficult to always observe all areas. Since various types of earth observation satellites are currently operating and the return cycle is from one day to several days, artificial satellites can monitor a power facility network in a wide area in a short time. On the other hand, ultraviolet rays due to corona discharge are generated because the insulation is partially destroyed in the atmosphere. In many cases, the dielectric breakdown causes separation of electrons and cations, which are accelerated by high voltage and collide with molecules in the atmosphere to emit ultraviolet rays. The phenomenon may occur in a very fine part. Since the resolution of the image analysis by the earth observation satellite currently in practical use is about 0.5 m, it is difficult to directly detect the corona discharge. Therefore, by providing corona discharge detection means and indirectly detecting the corona discharge, it is possible to monitor the state of occurrence of the corona discharge in the power equipment network extending over a wide area.

It is a system configuration figure of an embodiment of a corona discharge detection system by an artificial satellite image of the present invention. It is a figure which shows the corona detection means by application | coating of the coating material of this invention. It is a figure which shows the corona detection means by the photocatalyst of this invention. It is a figure explaining the principle of a photocatalyst. It is a figure which shows the corona detection means by the plant of this invention. It is a figure explaining an electric power grid system.

DESCRIPTION OF SYMBOLS 110 Artificial satellite 120 Reception antenna 130 Base station 140 Image analysis apparatus 150 Power equipment network 152 Power equipment 156 Corona discharge detection means

Hereinafter, the best mode for carrying out the present invention will be described with reference to the drawings. This is merely an example, and the technical scope of the present invention is not limited to this.

FIG. 1 is a system configuration diagram of an embodiment of a corona discharge detection system using artificial satellite images according to the present invention. FIG. 2 is a diagram showing a corona detection means by applying the paint of the present invention. As shown in FIGS. 1 and 2, a corona discharge occurred in the artificial satellite 110 having a device for photographing the power equipment network 152 on the earth surface 150 and transmitting the photographed image through a communication line, and the power equipment network 152. Corona discharge detection means 156 that can identify the location from the artificial satellite 110, an antenna 120 that receives an image transmitted from the artificial satellite 110, and information on the location of the corona discharge identified by the corona discharge detection means 156, and a base station And 130, and an image analysis device 140 for analyzing the received image.

As the artificial satellite 110, the earth observation satellite WorldView-1 currently in operation can be used. As a system using this satellite, for example, an image analysis system of Vision Tech Co., Ltd. can be used as the image analysis device 140. This is because the regression period is 1.7 days and the resolution is 1 m or less. *

FIG. 2 shows an example of corona detection means by applying paint to a steel tower 153 for a high-voltage power transmission line that is a part of the power equipment network 152. As shown in FIG. 2, the high-voltage power transmission tower 153 is vertically arranged in an overhead ground wire 159 and a two-line transmission circuit for transmitting three-phase alternating current, and 154U1, 154V1, 154W1, 154U2, 154V2, and 154W2. It is usual that power is transmitted through a wire. Each transmission line is often suspended by a suspension insulator 158. The length of the column that divides the two lines and suspends each transmission line is 4.8 to 6.3 m. Therefore, by irradiating ultraviolet rays generated by corona discharge to the

struts

156U, 156V, and 156W of each phase in FIG. 2, by applying a coating that emits fluorescence or phosphorescence, corona discharge is observed even when observed from an artificial satellite. It is possible to identify the power transmission facilities that are out.

As a paint that emits fluorescence when irradiated with ultraviolet rays generated by corona discharge, it may emit white light such as calcium halophosphate and calcium zinc phosphate used in fluorescent lamps. Eurobium-activated yttrium oxide having a fluorescent color of orange-red or magnesium fluoride germanate having a fluorescent color of deep red is preferable, but is not limited thereto. Further, for example, benzophenone can be used as the phosphorescent paint.

In addition, the equipment that emits fluorescence or phosphorescence when irradiated with ultraviolet rays generated by corona discharge is attached to the power equipment in a configuration that does not supply power with the same appearance as a commercially available fluorescent lamp. It is economical to be a thing. A fluorescent tube coated with europium-activated yttrium oxide whose fluorescent color is orange-red or magnesium fluoride germanate whose fluorescent color is deep red is desirable so that it can be distinguished from other light when observed at night. It is not limited to this. It is desirable to make a specific shape of the fluorescent tube by combining a plurality of ring-shaped and rod-shaped tubes so that they can be easily identified from an artificial satellite.

In this way, the location where the corona discharge from the artificial satellite is generated can be identified. Identify where the corona discharge occurred and provide information to the utility. The power company that is provided with the information can systematically investigate the site and eliminate the cause of corona discharge.

Example 2 is an example in which discoloration due to ultraviolet rays due to corona discharge is detected from an image from an artificial satellite in a power facility or the like. In particular, it can be detected effectively by utilizing a photocatalyst developed in recent years. This embodiment is advantageous in that it can detect that a corona discharge has occurred when the weather conditions change even when the satellite cannot be observed due to clouds or the like.

FIG. 3 is a diagram showing the corona detection means using the photocatalyst of the present invention, and FIG. 4 is a diagram for explaining the principle of the photocatalyst. Hereinafter, description will be made with reference to these drawings.

As shown in FIG. 3, the corona detection means using the photocatalyst according to the present invention has a high-voltage transmission line 254U2 suspended from a

long tube insulator

258A, 258B, 258C and a

long tube insulator

258D, 258E, 258F. It is effective in the case.

The photocatalyst that has made remarkable progress in recent years is that, when titanium oxide, an oxide semiconductor, absorbs light, electrons in the valence band are excited to the conduction band, and some of the holes and conduction electrons are combined. Although generating heat, these carriers other than the recombination process diffuse and reach the surface where they cause a chemical reaction. In the case of titanium oxide, it is known that this photoexcitation is a transition from the oxygen 2p orbital to the titanium 3d orbital, and its band gap is 3.2 eV, an anatase type often used as a photocatalyst, and a high temperature stable phase rutile. The mold is 3.0 eV. In terms of the wavelength of light, they are 388 nm and 413 nm. Therefore, in order to cause the photocatalytic reaction, ultraviolet rays having a shorter wavelength than this are required (see “Photocatalyst” by Akira Fujishima).

∙ Ultraviolet rays from corona discharge include short ultraviolet rays that are not included in the ultraviolet rays when sunlight reaches the earth's surface. In ordinary photocatalysts, titanium oxide is doped with a small amount of impurities so that it reacts with ordinary sunlight. The photocatalyst used in the present invention needs to be distinguished as to whether it has been stained and discolored by ultraviolet rays due to corona discharge observed from an artificial satellite or ultraviolet rays due to sunlight. Therefore, by using a photocatalyst that reacts with ultraviolet rays generated by corona discharge, if the contamination is removed by ultraviolet rays due to corona discharge, the difference can be detected by detecting the difference. As a photocatalyst that reacts with ultraviolet rays generated by corona discharge, a photocatalyst that has a band gap from a valence band to a conduction band of 3.0 eV or more and reacts with dark ultraviolet rays is a long tube, and 258A, 258B, 258C, 258D, 258E 258F, etc. With this configuration, when a corona discharge occurs, the photocatalyst reacts to remove contaminants on the surfaces of the

long tube insulators

258A, 258B, 258C and the

long tube insulators

258D, 258E, 258F, and becomes white and clean. Therefore, it is possible to detect even an image from an artificial satellite.

On the other hand, corona discharge often occurs due to salt damage in which salt is attached to the insulator. In this case, it is desirable to wash the insulator using a photocatalyst that reacts with ordinary sunlight. In that case, as shown in FIG. 3, a photocatalyst that reacts to sunlight is coated on

long insulators

258C and 258D that are close to the transmission line where creeping discharge is likely to occur, and a photocatalyst that reacts to corona discharge on other insulators. Can be coated. Even in this case, it can be detected that a corona discharge has occurred from an image observed from an artificial satellite.

Example 3 is an example in which a plant discoloration due to ultraviolet rays due to corona discharge is detected from an image from an artificial satellite in a power facility or the like. In particular, research on UV-resistant plants has been progressing in recent years, and it can be detected from artificial satellites due to the shape of letters to be planted by mixing B region UV-resistant mutant plants with other plants (special characteristics). Open 2007-228922 etc.). Even in this embodiment, it is advantageous that it is possible to detect that a corona discharge has occurred when the weather conditions change even when observation from an artificial satellite is not possible due to clouds or the like.

FIG. 5 is a diagram showing corona detection means by the plant of the present invention. As shown in FIG. 5 (A), a B region ultraviolet resistant mutant plant group 310 and a plant group 320 weak to B region ultraviolet light are planted on the land serving as the foundation of the high-voltage power transmission line. When corona discharge is generated, the plant group 320 that is sensitive to B region ultraviolet rays changes color, so it is possible to detect that corona discharge has occurred even from an image from an artificial satellite. Moreover, as shown in FIG. 5 (B), a plant group 340 that is vulnerable to B region ultraviolet rays in the shape of letters may be planted in the B region ultraviolet resistant mutant plant group 330.

As an example of the B region ultraviolet resistant mutant plant, an Arabidopsis B region ultraviolet resistant mutant plant can be employed (see JP2007-228922). For example, other B region ultraviolet resistant mutant plants such as rice may be used.

As mentioned above, although this invention was demonstrated using specific embodiment, the technical scope of this invention is not limited to the range as described in the said embodiment. For example, the corona discharge detection means has been described in the example of the fluorescent paint, the photocatalyst, and the plant planted in the vicinity, but other means may be used as long as it can be detected from the satellite image. Various modifications or improvements can be added to the above embodiment. It is apparent from the scope of the claims that the embodiments added with such changes or improvements can be included in the technical scope of the present invention.

Claims

An artificial satellite having a device for photographing a power facility network on the surface of the earth and transmitting the photographed image through a communication line;
Corona discharge detection means that can identify from the satellite where the corona discharge occurred in the power equipment network,
An image analysis device that receives and analyzes information transmitted from the artificial satellite for information on the location where the corona discharge specified by the corona discharge detection means has occurred;
Corona discharge detection system.
The corona discharge detection system according to claim 1, wherein the corona detection means is coated with a paint that emits fluorescence or phosphorescence when the power equipment is irradiated with ultraviolet rays generated by corona discharge.
The corona discharge detection system according to claim 1, wherein the corona detection means includes a device that emits fluorescence or phosphorescence when the power equipment is irradiated with ultraviolet rays generated by corona discharge.
2. The corona discharge detection system according to claim 1, wherein the corona detection means is applied with a paint that changes color when the power equipment is irradiated with ultraviolet rays generated by corona discharge.
The corona discharge detection system according to claim 1, wherein the corona detection means is a power facility coated with a photocatalyst.
6. The corona discharge detection system according to claim 5, wherein the photocatalyst reacts with ultraviolet rays generated by corona discharge.
The corona discharge detection system according to claim 1, wherein the corona detection means has planted a plant that changes color when irradiated with ultraviolet rays in the vicinity of the power equipment network.
An image analysis device used in a corona discharge detection system using satellite images,
An artificial satellite having a device for photographing a power equipment network on the surface of the earth and transmitting the photographed image through a communication line; and a corona discharge detecting means capable of identifying from the artificial satellite a location where a corona discharge has occurred in the power equipment network. An image analysis apparatus for receiving and analyzing information transmitted from the artificial satellite for information on the location where the corona discharge specified by the corona discharge detection means has occurred.