KR200183472Y1 - An apparatus for detecting abnormality of a power transmittion line - Google Patents

Abstract

The transmission line abnormality detection device of the present invention has an upper semi-cylindrical panel in which a plurality of coils in which current flows is wound several times, and a plurality of coils are wound in a plurality of times, and can be opened and closed with the upper semi-cylindrical panel. It is composed of a lower semi-cylindrical panel to be inserted, connected to the coil wound around the upper semi-cylindrical panel and the lower semi-cylinder panel to detect an abnormality of the transmission line inserted into the upper semi-cylindrical panel and the lower semi-cylindrical panel.

Description

Transmission line abnormality detection device {AN APPARATUS FOR DETECTING ABNORMALITY OF A POWER TRANSMITTION LINE}

The present invention relates to a transmission line inspection device. In particular, a high-voltage transmission line used in an electric ventilation plant and a transmission line abnormality detection for measuring the internal wire abnormality and corrosion degree of electric wires used to transmit electric power generated by a power plant to a substation. Relates to a device.

In general, many steelworks and transmission lines are constructed in steel mills. Especially, transmission lines that transmit electric power generated from electric blower plants and power plants to substations, general factories, and customers are the top line of power lines and transmission towers dedicated to the transportation of electric power. It can be largely divided into branch lines.

The power line should have electrical properties with good conductivity and mechanical properties capable of maintaining its inherent shape against external forces so as to stably supply power. The role of the overhead processing line is to play an important role to protect the power line from the dead and used as a return path of the fault current.

Currently hypothesized transmission lines are used Aluminum Conductor Steel Reinforced (ACSR) wires called galvanized steel core wires as shown in FIGS. 1 and 2.

These ACSR wires are provided with a plurality of aluminum wires 2 having excellent electric mobility on the surface, and a plurality of steel core wires 1 made of steel (Fe) having excellent tensile strength are provided inside these aluminum wires. The surface of the steel core 1 is plated with a zinc film 3 because the steel core uses a material having an affinity with aluminum to prevent corrosion caused by rust in combination with atmospheric processes, especially oxygen. to be. The zinc film has a plating thickness of about 0.4 mm and is formed through the manufacturing process of impregnation.

On the other hand, when the ACSR line is installed as a power transmission line, as well as the characteristics of the steel mill facility itself, when the steel mill is located on the shore, when the rain falls in a state where pollutants such as salinity or sulfurous acid gas contained in the air are accumulated on the wire, It penetrates into the wire and causes an electrolyte-like action on the contact surface where the three metals are in contact, so that a local battery is formed between dissimilar metals.

As a result, aluminum, zinc and iron are corroded in order, and the ionization phenomenon causes electrolytic corrosion, so that the aluminum wire 2 becomes weak as a conductor, and the strong core wire 1 weakens mechanical strength. Each plant facility, which is an integrated steelworks, has a huge impact on production and cost. On the other hand, this state occurs inside the wire, but since the outside is kept dry, it is hardly distinguished by the naked eye. This phenomenon is particularly acute when the ACSR wire is used in a coastline or industrial area.

When such a phenomenon occurs, various disadvantageous situations may be caused, such as a stable power supply in the steel mill, which may be prevented. Therefore, it is necessary to detect this in advance and take precautionary measures.

As described above, in order to solve the problem of the transmission line of the electric transmission factory, the degree of corrosion inside the transmission line must be inspected. In the related art, the inside of the transmission line was cut and examined.

However, this method requires a lot of manpower and time, and requires a large amount of manpower and time, since the sample must be taken from the transmission line and then dismantled to examine the corrosion. It was difficult, and there was a problem that the precision was also lowered.

The proposed method to solve this problem is to use the eddy current which is known to be feasible and reliable among the non-destructive methods. 3 shows a conventional apparatus for detecting the presence or absence of an abnormality in a transmission line using such a complete flow.

Eddy current means a circular current induced in an electric conductor adjacent to a coil by a magnetic field generated by the coil. When an alternating current is applied from the AC power supply 12 to the coil, a magnetic field is formed, and the electric conductor plate is caused by the magnetic field. Eddy currents are generated within. The generated eddy currents form a new magnetic field in the opposite direction to the magnetic field generated by the test coil, and the two kinds of magnetic fields interact with each other causing a change in the impedance of the test coil.

In addition, when a test body such as the distribution line transmission line 10 is inserted into the solenoid 11 and an alternating current is applied to the coil, a main magnetic field is generated, and an eddy current is generated inside the test body by the main magnetic field. The generated eddy current generates an eddy current magnetic field toward the solenoid 11, thereby canceling the main magnetic field generated in the coil. This results in a change in magnitude and phase of the current i (t) flowing in the coil.

This change in magnitude and phase of the current eventually changes the impedance of the coil. The magnitude and phase of the impedance can be calculated from the voltage υ (t) applied by the impedance measuring instrument 13 and the measured current. As a result, the size and shape of the defect included in the test specimen such as the transmission line and the power distribution can be estimated from the information on the magnitude and phase of the calculated impedance. This nondestructive inspection method is called eddy current flaw detection.

The detection sensor 14 used when inspecting a sample of a transmission line by a conventional eddy current flaw detection method inserts a test body such as the transmission line 10 into a detection sensor made of a solenoid 11 and applies AC power to the coil. Method is used.

As described above, when AC power is applied to the detection sensor 14 made of a solenoid, a magnetic field is formed in the coil, and an eddy current is generated in the transmission line 10 by the magnetic field. Since the generated eddy currents form a new magnetic field in the opposite direction to the applied magnetic field, these two types of magnetic fields cause the impedance change of the solenoid 11, thereby measuring the change in electrical characteristics connected in parallel to the solenoid. Meter 13 detects this change.

In addition, the degree of corrosion of the transmission line is detected by comparing the change in electrical characteristics measured by the method described above with the standard data on the change of electrical characteristics of the transmission line in which normal transmission lines and various internal corrosion occurrences are confirmed.

However, in the case of the detection device having a long winding solenoid as described above, there are many difficulties in inspecting a transmission line or an elongated transmission line in which electric poles and insulators are actually installed. That is, in order to inspect the degree of corrosion inside the transmission line, the transmission line had to be cut and inspected. Therefore, there is a problem that requires a lot of manpower and time since the corrosion state must be examined after taking a sample and dismantling the wire. In addition, there was also a problem that the precision is poor because it is necessary to identify the corrosion state of all the facilities in the facility from a small number of samples collected.

The present invention is to solve the above problems, the coil is wound on the upper cylindrical panel and the lower cylindrical panel to make the coil semi-cylindrical, and the semi-cylindrical coil is coupled to the cylindrical coil to facilitate the wire inside the sensor. An object of the present invention is to provide an apparatus for detecting an abnormality of a transmission line that can be attached or detached.

In order to achieve the above object, the transmission line abnormality detection device of the present invention is the upper semi-cylindrical panel winding a plurality of coils through which a current flows a plurality of times, the plurality of coils are wound several times and opened and closed with the upper semi-cylindrical panel It is possible to be connected to the lower semi-cylindrical panel, the transmission line is inserted therein, and the coil wound around the upper semi-cylindrical panel and the lower semi-cylindrical panel to prevent the abnormality of the transmission line inserted into the upper semi-cylindrical panel and the lower semi-cylindrical panel. It consists of a detection part which examines.

The detection unit is connected to the coil wound on the upper semi-cylindrical panel and the coil wound on the lower semi-cylindrical panel to measure a signal and output a current signal, and a current to convert the current signal output from the measuring device into a voltage signal And a voltage converter, a monitor switch for generating an alarm and a lamp by operating a relay when the signal is larger than the set value by comparing the signal input from the current / voltage converter with a set value, and a control panel for controlling devices of the detector.

1 is a view showing the shape of the transmission line of the electric blower factory

2 is a cross-sectional view of a transmission line of an electric ventilation factory.

3 is a view showing a conventional electric blower transmission line abnormality detection device.

4 is a view showing an electric wind transmission line abnormality detection device according to the present invention.

5 is a view showing a coil unit of the transmission line abnormality detection apparatus according to the present invention shown in FIG.

Figure 6 is a view showing a coil winding method in the transmission line abnormality detection apparatus according to the present invention.

-Explanation of symbols for the main parts of the drawings-

12 AC power 13 Impedance meter

21: Lower semi-cylindrical panel 22: Upper semi-cylindrical panel

31,32: first coil 33,34: second coil

48: isolator 50: current / voltage converter

51 monitor switch 54 control panel

55,56: Relay

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

4 is a view showing the abnormality detection apparatus for the electric transmission line according to the present invention. The upper part of the figure shows a detection sensor composed of a coil part for generating an eddy current in the transmission line, and the control block is shown below.

The detection sensor is composed of an upper semi-cylindrical coil 41 and a lower semi-cylindrical coil 42. The upper semi-cylindrical coil 41 is composed of first and second coils 31 and 32, and has a lower semi-cylindrical shape. The coil 42 is composed of third and fourth coils 33 and 34. Both terminals of the first to fourth coils 31, 32, 33, and 34 are classified into ai, ao, bi, bo, ci, co, di, and do, respectively, and one side of the both terminals, for example, the first to fourth terminals. When the current flows into ai, bi, ci, di of the fourth coil, the direction of the current becomes like an arrow.

As will be described later, in the case of the first to second coils, current flow directions between adjacent conductors become the same direction, which is the same in the third and fourth coils.

In the figure, the coils wound at the center portion have a circular current in a counterclockwise direction, whereas the coils wound at both ends have a circular current in a clockwise direction.

When the upper semi-cylindrical coil 41 and the lower semi-cylindrical coil 42 are combined in a cylindrical shape, it acts as if a circular current flows like a conventional solenoid. At this time, when the upper semi-cylindrical coil 41 and the lower semi-cylinder coil 42 are combined in a cylindrical shape, the current flowing in a portion closest to the upper semi-cylindrical coil 41 and the lower semi-cylindrical coil 42 correspond to each other. The upper semi-cylindrical coil 41 and the lower semi-cylindrical coil 42 are made in opposite directions to each other and the magnetic fields generated in this portion cancel each other out. The test is performed using a magnetic field offset as described above.

One side terminals (ai, bi, ci, di) of the first to fourth coils (31, 32, 33, 34) provided in the upper and lower semi-cylindrical coils (41, 42) and the first to fourth coils ( The other terminals (ao, bo, co, do) of 31, 32, 33 and 34 are connected to the measuring device 13 and the AC power supply 12 for measuring the change in electrical characteristics.

When power is supplied from the AC power source 12, an eddy current is generated in the coil, and the measuring device 13 measures the eddy current. When the AC power supply 12 is constantly applied, the impedance generated in the coil varies according to the abnormality of the power line inserted into the detection device and the degree of corrosion, and the change of the impedance can be measured by the measuring device 13.

In the conventional design, since the wire to be inspected is cut and only the portion thereof is inspected, there is a problem of selecting and inspecting several sections of the section arbitrarily, and since there is a degree difference depending on the environment of the wire, almost all the processing ground wires And because the height of the track is more than 15m there was a significant difficulty and risk in sampling.

However, in the present invention, only one installation of the device can solve all problems. That is, the signal detected by the measuring device 13 is output as a current signal of 4-20mA to enable long-distance transmission, and isolator (48) isolator to prevent the device installed in the field from being damaged by lightning, overcurrent or voltage. ) To amplify a good signal and protect both signal sources without dropping the measured signal. Since the isolator 48 completely separates both signals, even if only one of the loops of both signals fails, the other can be protected.

The amplified 4-20 mA current signal is converted into a voltage of 1-5 V by the current / voltage converter 50 and a control loop is constructed using the converted signal as follows. The reason for converting a current signal of 4-20 mA into a voltage signal is that a 4-20 mA signal can be transmitted without a drop in a long distance transmission, and the voltage signal must be separated in the control panel. I use it. In addition, since the signals can be used in parallel, they can be used without the down of each instrument signal.

When the amplification and insulation signals are input to the monitor switch 51 and become 10% or more based on 10% of the set signal, it is determined that there is an error in the wire, and the relay 56 is contacted and an alarm 58 is issued. If it is below, it judges that a wire is good and continues operation.

In addition, when the monitor switch 51 is set to 20% and becomes 20% or more, it is determined that the corrosion degree of the wire is severe, and the danger lamp 57 which contacts the relay 55 and informs the immediate replacement of the wire turns on. The driver can make the judgment immediately without checking.

The monitor switch 51 outputs a current signal, which is input to the detection index index 53 and input to the control panel 54. At this time, the scale of the detection value indicating section is set to 0 to 100%. This output signal is recorded in the recorder 60 so as to predict the corrosion state of the electric wire up to now and the state of the electric wire in the future. All these signals are managed and controlled by the control panel 54.

5 is a perspective view showing a detection sensor 26 of the transmission line abnormality detection device manufactured by the present invention, the first and second surfaces of the upper semi-cylindrical panel 22 and the surface of the lower semi-cylindrical panel 21. The second coils 31 and 32 and the third and fourth coils 33 and 34 are wound a plurality of times, respectively, so that the coils are wound into the first and second coils 31 and 32 and the third and fourth coils 33, At the central part adjacent to 34), windings are made to flow in a circular current in the same direction.

The direction of the circular current flowing through the coils located at the center and left and right ends of the detection sensor 26 is reversed, and the part in which the coil is densely wound is divided into three areas, and the three areas are spaced at regular intervals. Among them, the area used as the sensing part is the center part and the length is L, and other areas except the center part are used as the non-sensing part.

For reference, in order to facilitate the opening and closing of the upper semi-cylindrical panel 22 and the lower semi-cylindrical panel 22, for example, the hinge 26 on one side of the upper semi-cylindrical panel 22 and the lower semi-cylindrical panel 21. It may be provided, and may be provided with a fixing means on the opposite side. In addition, as the upper semi-cylindrical panel 22 and the lower semi-cylindrical panel 21 are inserted, a separate auxiliary means capable of opening and closing the plate cylindrical panel may be used.

A coil is wound around the surface of the semi-cylindrical panel in turn, and thus a method of winding the coil in such a manner that the current flowing in the adjacent conductive wire is the same will be described in more detail with reference to FIG. 6.

6 illustrates a method of winding a coil on the semi-cylindrical panel. For example, when the first coil 31 is wound on the upper semi-cylindrical panel 22, the upper and lower sides of the upper semi-cylindrical panel 22 are wound. For example, C1..C10 and K1..K10 protruding members 23 are provided at an end spaced apart from each other, and one side terminal ai of the first coil 31 is disposed in the same current direction in adjacent conductors. It is drawn out from the protruding member at the outermost part, and the other terminal (ao) of the first coil 31 is drawn out to the inner protruding member.

In other words, the winding direction of the coil continues in the order of the outermost protrusion member C1 to K1, K10, C10, C2, K2, K9, C9 and is drawn out to the outside through the innermost protrusion members K6 and C6. The coil wound on the protruding members in the clockwise direction, and the coil wound on the protruding members on the right side is wound so as to proceed in the counterclockwise direction.

For reference, the spacing between C5, K5 and C6, K6 of the protruding member should be larger than the spacing between other protruding members so as not to affect the sensing region by the coil wound in the non-sensing region.

The second coil 32 is also wound around the central portion in a symmetrical structure, and the third and fourth coils 33 and 34 are vertically symmetrical with the first and second coils 31 and 32. Coil is wound.

Another embodiment of the present invention is similar to the above embodiment, but only the first coil and the third coil is provided in the upper semi-cylindrical coil and the lower semi-cylindrical coil of the detection sensor, and the number of turns is increased. In this case, if only one side of the left and right sides is used as the sensing area, the same effect as in the above-described embodiment can be obtained.

On the other hand, the following factors affect the eddy current inspection method applied to the above-described transmission line abnormality detection device.

First, the applied AC frequency: If the AC frequency is large, the eddy current becomes large, but it only acts on the surface by the skin effect, so these two effects should be appropriately selected.

Second, the conductivity of the test object: The greater the conductivity, the greater the magnitude of the eddy current. However, the conductivity is a test subject's own value and is not an externally controllable factor.

Third, the permeability of the test subject: The greater the permeability, the more eddy currents are generated.

Fourth, the shape and dimensions of the test coil and the relative position of the test coil and the test object.

As described above, the present invention is made of the upper semi-cylindrical coil and the lower semi-cylindrical coil to easily attach and detach the transmission line to the detection device for detecting the corrosion degree of the transmission line without cutting the transmission line even where the transmission line is installed. The degree of corrosion of the transmission line can be easily detected. As a result, the time used to detect the degree of corrosion of the transmission line can be saved, and the cost can be reduced by minimizing the required manpower.

Claims (3)

An upper semi-cylindrical panel in which a plurality of coils in which current flows is wound several times; A lower semi-cylindrical panel in which a plurality of coils are wound several times and opened and closed with the upper semi-cylindrical panel so that a transmission line is inserted therein; And And a detection unit connected to the coil wound around the upper semi-cylindrical panel and the lower semi-cylinder panel to detect an abnormality of a transmission line inserted into the upper semi-cylindrical panel and the lower semi-cylindrical panel. The method of claim 1, wherein the detection unit, A measuring device connected to the coil wound on the upper semi-cylindrical panel and the coil wound on the lower semi-cylindrical panel to measure a signal and output a current signal; A current / voltage converter converting the current signal output from the measuring device into a voltage signal; A monitor switch which compares a signal input from the current / voltage converter with a set value and activates a relay to emit an alarm and a lamp when the signal is larger than the set value; And Apparatus comprising a control panel for controlling the devices of the detection unit. 3. The apparatus of claim 2, further comprising an isolator coupled to the meter for separating the input signals from the coil wound on the upper semi-cylindrical panel and the coil wound on the lower semi-cylindrical panel.