KR20070078195A - System and method for detecting a partial discharge of a powercable - Google Patents

Abstract

A system and a method for detecting degradation of a power cable connecting part are provided to detect and monitor the temperature state of the connecting part in real time by connecting a spot sensor attached on the connecting part to the degradation detecting system, thereby reducing the inspection cost and preventing an accident. A system for detecting degradation of a power cable connecting part is composed of a storing unit(210) storing basic information about the connecting part of a power cable and alarm reference temperature; a connecting part temperature measuring unit(220) measuring the temperature of the connecting part by using a spot sensor; a cable peripheral temperature measuring unit(230) measuring the peripheral temperature of the power cable; an alarm temperature comparing unit comparing the temperature of the connecting part measured by the connecting part temperature measuring unit with the alarm reference temperature; a peripheral temperature comparing unit(250) comparing the temperature of the connecting part and the peripheral temperature of the power cable measured by the cable peripheral temperature measuring unit; and an alarm unit(260) generating an alarm if values of the alarm temperature comparing unit and the peripheral temperature comparing unit are over a predetermined range.

Description

Deterioration detection system and detection method of power cable connection {SYSTEM AND METHOD FOR DETECTING A PARTIAL DISCHARGE OF A POWERCABLE}

1 is an exemplary diagram of a conventional system for identifying a point where a power cable failure occurs

2 is a conceptual diagram of the minimum resolution (spacial resolution) of the optical fiber cable

Figure 3a shows a spot sensor according to the invention

3B illustrates a spot sensor according to another embodiment of the present invention.

4 is an exemplary view of a state in which a spot sensor according to the present invention is installed at a connection of a power cable;

Figure 5a is an exemplary view when installing the spot sensor in a plurality of rows in the power cable according to the present invention

5B is an exemplary view of a state in which optical fiber cable connections of a spot sensor are connected in series in FIG. 5A;

6 is an exemplary view of a state in which the optical fiber cable according to the present invention forms a loop section;

7 is an exemplary view showing a state in which the temperature of the power cable is measured in real time by the degradation detection system according to the present invention.

8 is a block diagram of a degradation detection system according to the present invention.

9 is a flowchart for explaining an operation procedure of the degradation detection system according to the present invention.

<Code Description of Main Parts of Drawing>

100: spot sensor 110: case

120: filler 130: seal

200: degradation detection system 210: storage unit

220: connection temperature measuring unit 230: cable ambient temperature measuring unit

240: measurement temperature comparison unit 250: ambient temperature comparison unit

260: alarm unit 270: ranking unit

280: history storage unit

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power cable connection deterioration detection system and a degradation detection method for detecting abnormal overheating of a connection at an early stage. More particularly, the present invention relates to a spot sensor manufactured using an optical fiber cable. To monitor the deterioration of the cable connection as well as to monitor the deterioration of the cable connection by attaching the same to the most accidental connection part of the power cable to detect the deterioration of the power cable connection that enables accurate deterioration monitoring against the ambient temperature of the power cable. The present invention relates to a system and a method for detecting degradation.

In general, the manufacture of extra-high voltage underground power cable is not to produce the entire length of the power section, but to produce a cable with a constant length of 200 ~ 300 m and install it in the underground power section. Between the installed power cable and the power cable is formed as a connection portion, is drawn to the outside through the underground termination junction box and connected to the electrical equipment and the like.

At this time, since the quality inspection is performed in various ways in the manufacturing process of the power cable, there is almost no problem, but the connection part to which the power cable is connected at the construction site is difficult to manage the construction, The effective detection method is limited, which causes a power cable accident due to deterioration of the connection.

Accordingly, in Korean Patent Registration No. 104422, an optical fiber arrangement for power cable line occurrence position detection system for detecting degradation of underground power cable in the longitudinal direction of the power cable is proposed.

However, the conventional invention is an optical fiber arrangement structure that detects a temperature rise position and a failure position by arranging the optical fiber 5 in the longitudinal direction along the power cable 1, as shown in FIG. 5) is configured to overlap a part of each other in the connection portion 2 of the power cable 1, but due to the characteristics of the optical fiber distribution temperature measurement device is a minimum resolution (spacial resolution) that is the distance at which the light laser incident from the light source receives energy at the same time Because it does not meet, there is a problem that can not measure the accurate degradation temperature.

Specifically, as shown in FIG. 2, when the distribution temperature is measured using the optical fiber cable, the minimum section 7a of the optical fiber cable capable of detecting the temperature change due to the limitation of the width of the incident laser pulse 7 is need. That is, if the laser pulse 7 width is 20 nm according to the characteristics of the laser diode (hereinafter referred to as LD), the minimum resolution (7a) is 4 m based on the speed of 20 nm * light (2 x 10E8 m / sec). Will be. This means that when a laser having a pulse width of 20 nm is incident, the accurate temperature can be measured only when the temperature of at least 4 m is constant, and the LD cannot reduce the pulse width below a certain width according to the characteristics of the optical system.

Therefore, when referring to the above characteristics, in order to measure the temperature of the power cable connection portion, the conventional technique is difficult to secure a minimum resolution (spacial resolution) 7a in the entire section of the power cable (1), It is difficult to measure the correct temperature.

In addition, the temperature of the power cable (seasonal factors, the relationship with the ambient temperature, etc.) does not reflect the rise or fall of the temperature, such a conventional measuring method is the processing apparatus 6 for each connection (2) ), There is a problem in that excessive installation cost is required due to the large number of processing devices (6).

Therefore, the present invention was devised to solve the problems of the prior art, and the main object of the present invention is to detect the degradation of the power cable connection portion more accurately.

Another object of the present invention is to provide a deterioration detection system and a deterioration detection method that detect an accurate deterioration in response to a change in the ambient temperature of a power cable connection and have a low installation cost for deterioration detection.

Storage unit for inputting and storing the connection unit basic information and the alarm reference temperature of the power cable to achieve the object of the present invention as described above; A connection part temperature measuring unit measuring a temperature of the power cable connection unit using a spot sensor; A cable ambient temperature measuring unit measuring a temperature around the power cable; An alarm temperature comparison unit for comparing the temperature of the connection unit measured by the connection unit temperature measuring unit with an alarm reference temperature of the storage unit; An ambient temperature comparison unit for comparing the connection temperature measured by the connection temperature measurement unit with the ambient temperature of the power cable measured by the cable ambient temperature measurement unit; And an alarm unit for generating an alarm when the value of the alarm temperature comparator is greater than or equal to a predetermined range or the value of the ambient temperature comparator is greater than or equal to a predetermined range.

In addition, the present invention is characterized by managing the connection by giving a rank to each connection according to the temperature measured by the connection temperature measurement unit.

In addition, the spot sensor of the present invention includes a heat-resistant case of a predetermined size and thickness coupled to the connection portion; An optical fiber cable which is drawn into the inside of one side of the case and is installed in left and right zigzag form at a predetermined interval and withdrawn to the outside of the case, and at one end thereof, a deterioration detection device is coupled; A thermally conductive filler filled in the case; Characterized in that it comprises a sealing member for sealing the heat conduction filler so as not to leak out of the case.

In addition, the present invention is characterized in that the optical fiber cable of the spot sensor is drawn from one side of the case is installed inside the case and then drawn out to the side again.

In addition, the present invention is characterized in that a plurality of rows of the spot sensor is coupled to the connection portion, and the optical fiber cables of each spot sensor are connected in series with each other.

In addition, the present invention is characterized in that to form a loop section of a predetermined length in the fiber optic cable middle portion installed in the power cable to measure the power cable ambient temperature.

In addition, the present invention comprises the steps of inputting and storing the reference information and the alarm reference temperature of the power cable connection to the storage unit; Measuring a temperature of each connection of the power cables by a connection temperature measuring unit; Managing the temperature by measuring the temperature of each connection part by a ranking part; Measuring a temperature around the power cable by the cable ambient temperature measuring unit; Comparing the measured connection part temperature with an alarm reference temperature by a measurement temperature comparison part; Comparing the temperature of the connection portion with the ambient temperature of the power cable by an ambient temperature comparison unit if the temperature of the connection portion is equal to or higher than the alarm reference temperature; And generating an alarm by the alarm unit when the measured connection part temperature is equal to or greater than the alarm reference temperature and the value of the ambient temperature comparator is equal to or greater than a predetermined range.

Hereinafter, the configuration of the most preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

3 is a view showing a spot sensor according to the present invention, Figure 4 is an illustration of a state in which the spot sensor according to the invention is installed in the connection of the power cable, Figure 5a is a spot sensor according to the present invention to the power cable 5B is an exemplary diagram when a plurality of rows are installed, and FIG. 5B is an exemplary diagram of a state in which optical fiber cable connections of a spot sensor are connected in series in FIG. 5A. 6 is an exemplary view showing a state in which the optical fiber cable according to the present invention forms a loop section, and FIG. 7 is an exemplary view showing a state in which the temperature of the power cable is measured in real time by the degradation detection system according to the present invention. 8 is a block diagram of a degradation detection system according to the present invention, and FIG. 9 is a flowchart for explaining an operation procedure of the degradation detection system according to the present invention.

The present invention relates to a power cable connection abnormality detection system and a degradation detection method using an optical fiber cable that enables early detection of abnormal overheating of the linear connection part (11) in installing the power cable (10). In the present invention, a spot sensor 100 manufactured using the optical fiber cable 20 is provided.

The spot sensor 100 is attached to the upper portion so as to behave in the connection portion 11 of the power cable 10, the most accident occurs in the power cable is configured to measure the temperature of the cable connection portion 11, It is configured to enable accurate monitoring of the degradation by comparing the relationship with the ambient temperature of the power cable 10 and connecting the degradation detection system 200 to one end of the optical fiber cable 20 so as to detect abnormal overheating at an early stage. do.

Therefore, the present invention enables accurate measurement of temperature when abnormal overheating occurs in the connection part 11 of the power cable, and efficiently detects it so as to prevent a large accident in advance. It is characterized by trying to ensure reliability.

According to the present invention, the basic information such as the peripheral information for each length of the power cable 10 of the connection portion 11 to which the power cable 10 of a predetermined length is continuously connected (S100), and the temperature of the connection portion 11 When the temperature exceeds a predetermined temperature, the alarm reference temperature is first input to the storage 210 to generate an alarm (S110).

Then, the spot sensor 100 of the present invention is attached to the connection part 11, and the temperature of each connection part 11 transmitted through the spot sensor 100 is measured in real time by the connection part temperature measuring part 220. (S120).

3A illustrates a spot sensor according to the present invention, wherein the spot sensor 100 has a predetermined size and thickness, and includes a heat resistant case 110 made of an MC material capable of withstanding high temperatures without being affected by electromagnetic waves. After inserting the optical fiber cable 20 into one side of the case 110, the apparatus 110 is repeatedly installed several times so as not to contact each other in a zigzag form from side to side in the case 110, and then drawn out again to the outside of the case 110. Therefore, the spot sensor 100 of the present invention can be accurately measured because the optical fiber cable 20 of the length that can ensure the minimum section is installed in the case 110.

The optical fiber cable 20 introduced into the spot sensor 100 may be drawn out to one side of the case 110 and then drawn out to the other side. However, the optical fiber cable 20 may be pulled out again so as not to be joined to the inserted side as shown in FIG. 3B. It is possible.

The filler 120 is filled in the case 110 of the spot sensor 100 so that the optical fiber cable 20 is fixed in the case 110, and the filler 120 is formed outside the case 110. It is preferable to fill the carbon-based filler 120 having excellent heat transfer. In addition, the inlet through which the optical fiber cable 20 is drawn in and drawn out is sealed with seals 130 made of various materials such as rubber or silicon so that the filler 120 inside the case 110 does not leak to the outside.

Meanwhile, as shown in FIGS. 5A and 5B, the spot sensor 100 may be installed in a plurality of rows in the power cable 10 to detect deterioration at each point, and as shown in FIG. 5A, a plurality of spot sensors ( In the case where 100) is installed in a row in multiple stages, an optical switching switch 30 is required to select the spot sensor 100 to be measured. However, as shown in FIG. 5B, the spot switch 100 is drawn out from one spot sensor 100. When the optical fiber cable 20 is introduced into the inlet of another spot sensor 100a, and the optical fiber cable 20 drawn out from the spot sensor 100a is again introduced into the next spot sensor 100b, and connected in series with each other. Even if the spot sensor 100 is installed in multiple stages, the optical switch 30 is not necessary.

A connection temperature measuring unit 220 for measuring the temperature of the light transmitted through the optical fiber cable 20 of the spot sensor 100 and measuring the temperature is provided. Similarly, the light transmitted from the loop section 21 of the optical fiber cable 20 is provided. The cable ambient temperature measuring unit 230 for measuring the ambient temperature of the predetermined point of the power cable 10 is analyzed.

In addition, an alarm temperature comparison unit 240 for comparing the measured temperature of the connection unit 11 with the alarm temperature stored in the storage unit 210 is provided, and the temperature of the measured connection unit 11 around the power cable 10 is provided. By providing the ambient temperature comparison unit 260 to compare with the temperature, if the measured temperature of the connecting portion 11 is out of the alarm temperature and the ambient temperature of the power cable 10 or more than a predetermined range, the alarm unit 260 generates an alarm. .

Hereinafter, the operation of the present invention configured as described above is as follows.

The optical fiber cable 20 is laid along the power cable 10, and the spot sensor 100 of the present invention is firmly attached to the connection part 11, and the optical fiber cable 20 between the connection part and the connection part is bent by a predetermined length. The loop section 21 is formed by drawing out.

In addition, the temperature of each of the connection units 11 measured by the connection unit temperature measuring unit 220 is compared with the alarm temperature pre-stored in the storage unit 210 and the alarm temperature comparison unit 240, respectively. If it does not matter, if it is out of the range of the alarm temperature, it is irrelevant if the measured temperature of the connection portion 11 again within the predetermined range compared to the cable ambient temperature by the ambient temperature comparator 250, but the difference outside the range If there is an alarm unit 250 generates a warning signal or warning sound.

That is, according to the law of Joule heat, the power cable 10 increases in temperature by the resistance, current, and conduction time of the inner conductor of the power cable 10, and is operated while being exposed to various external influences. Depending on the temperature, the external temperature of the power cable 10 is raised or lowered. Accordingly, in order to measure the accurate temperature of the connection portion 11, it is preferable to consider the relation with the ambient temperature of the power cable 10.

Since the temperature of the power cable 10 is affected by the temperature generated by the current flowing through the conductor and the ambient temperature caused by external environmental influences, the temperature of the power cable 10 can be measured at regular intervals so that the ambient temperature of the power cable 10 can be measured. By forming a loop section 21 on a part of the optical fiber cable 10 to measure the ambient temperature of the power cable 10, in the power cable degradation monitoring system 200, the power cable connection 11 temperature and the mutual comparison logic are added. Allow accurate detection of degradation.

Accordingly, when abnormal power degradation of the power cable 10 occurs, the correlation between the measured temperature of the spot sensor 100 attached to the power cable connection part 11 and the same behavior and the ambient temperature of the cable is compared with each other. It is possible to determine the exact deterioration of 10).

In addition, it is possible to efficiently manage the connection portion 11 by assigning the ranking of the measurement temperature of each connection portion 11 by the ranking portion 270 to centrally manage the most dangerous connection portion 11.

Referring to the capture screen according to an embodiment of the present invention, the power cable connecting portion 11 at the 233 m point in the longitudinal direction of the power cable 10 has a temperature of 60 ° or more compared to the connecting portion 11 at the 550m, 850m, and 1150m points. You can see the rise.

That is, the temperature may rise due to a factor of changing the temperature of the predetermined connection part 11, for example, looseness or insulation of the predetermined point connection part 11. By generating a proper maintenance can be made, it is possible to prevent equipment accidents due to the connection (11) or more in advance.

As described above, the present invention closely attaches a spot sensor using an optical fiber cable to a connection part of a power cable, and connects it with a deterioration detection system to detect and monitor a temperature condition induced in the connection part of a power cable in real time, thereby checking the cost. It is a very useful invention that can prevent human and material loss in advance by reducing power loss and preventing electric power accidents that may occur from accidents.

In addition, the monitoring system of the present invention increases the number of years of use of the power cable, has the effect of significantly reducing the inspection cost, and detects the partial high temperature heat generated by the degradation of the cable, the power according to the peak load in summer There is an effect that can improve the power transmission efficiency.

Claims (7)

A storage unit for inputting and storing the basic information and the alarm reference temperature of the power cable; A connection part temperature measuring unit measuring a temperature of the power cable connection unit using a spot sensor; A cable ambient temperature measuring unit measuring a temperature around the power cable; An alarm temperature comparison unit for comparing the temperature of the connection unit measured by the connection unit temperature measuring unit with an alarm reference temperature of the storage unit; An ambient temperature comparison unit comparing the connection unit temperature measured by the connection unit temperature measuring unit with the ambient temperature of the cable measured by the power cable ambient temperature measuring unit; An alarm unit for generating an alarm when the value of the alarm temperature comparator is greater than or equal to a predetermined range and the value of the ambient temperature comparator is greater than or equal to a predetermined range; Power cable connection deterioration detection system, characterized in that consisting of. The method of claim 1, And a power cable connection deterioration detection system, wherein the connection is managed by assigning a ranking to each connection according to the temperature measured by the connection temperature measuring unit. The method of claim 1, wherein the spot sensor, A heat resistant case of a predetermined size and thickness coupled to the connecting portion; An optical fiber cable which is drawn into the inside of the case and is installed in left and right zig-zags at predetermined intervals and then withdrawn to the outside of the case, and a deterioration detection system is coupled to one end; A thermally conductive filler filled in the case; And a sealing hole for sealing the heat conduction filler so that it does not leak out of the case. The method of claim 3, wherein The optical fiber cable of the spot sensor is drawn from one side of the case is installed in the case inside the power cable connection deterioration detection system, characterized in that is drawn out again. The method of claim 3, wherein And a plurality of rows of the spot sensors coupled to the connecting portion, and the optical fiber cables of the respective spot sensors are connected in series with each other. The method according to claim 3 or 5, The power cable connection deterioration detection system, characterized in that to form a loop section of a predetermined length so as to escape the power cable in the fiber optic cable middle portion installed in the power cable to measure the ambient temperature of the power cable. Inputting and storing reference information and alarm reference temperature of the power cable connection unit into the storage unit; Measuring a temperature of each connection of the power cables by a connection temperature measuring unit; Managing the temperature by measuring the temperature of each connection part by a ranking part; Measuring a temperature around the power cable by the cable ambient temperature measuring unit; Comparing the measured connection part temperature with an alarm reference temperature by a measurement temperature comparison part; Comparing the temperature of the connection portion with the ambient temperature of the power cable by an ambient temperature comparison unit if the temperature of the connection portion is equal to or higher than the alarm reference temperature; Generating an alarm by the alarm unit when the measured connection part temperature is equal to or greater than the alarm reference temperature and the value of the ambient temperature comparator is equal to or greater than a predetermined range; Deterioration detection method of the power cable connection characterized in that consisting of.

Images