KR102036456B1 - Apparatus and method for detecting fault of combined transmission line - Google Patents

Abstract

Detects the failure of the underground transmission line and overhead transmission line on the basis of the fault currents detected by the current transformer sensors installed on the main line of the underground transmission line, and detects the failure of the complex transmission line to identify the point of failure in case of the failure of the underground transmission line An apparatus and method are presented. The proposed composite transmission line fault detection device collects and synchronizes fault currents from the input current transformer sensor and the output current transformer sensor installed in the underground transmission line, and breaks one of the overhead transmission line and the underground transmission line based on the current direction of the synchronized fault current. Detecting in section, and detecting underground transmission line in fault section, detects fault location based on the phase change of synchronized fault current.

Description

Device and method for detecting failure of complex transmission line {APPARATUS AND METHOD FOR DETECTING FAULT OF COMBINED TRANSMISSION LINE}

The present invention relates to an apparatus and method for detecting a failure of a composite transmission line, and more particularly, to an apparatus and method for detecting a failure of a composite transmission line for detecting a failure occurring in a composite transmission line in which an underground transmission line and a overhead transmission line are mixed. .

Recently, due to the rapid growth of the industrial economy, electric power demand is increasing year by year. Power consumption during the summer peak season is nearly equal to the total supply of power supply facilities, and national cooperation is required every year. In addition, the rapid increase in electric energy consumption caused by various small industries, large buildings, and large apartment complexes, as well as the rapid population overcrowding trend of cities, now requires large-scale transmission in urban areas. As a result, construction of underground transmission lines and complex transmission lines combining processing and underground are gradually increasing.

Digital distance relays are used to block the failure section in case of an accident such as ground fault in the transmission line. The distance relay accurately measures the line impedance from the relay installation point to the failure point, determines the fault section, and generates a trip signal to protect the transmission line.

The above range relay operates when the line impedance to the accident point is measured according to the voltage and current when an accident occurs in the transmission line, and it operates when the value is below the pre-corrected value. It is much easier to apply than a relay and is used a lot.

However, the impedance calculation algorithm of the distance relay currently applied to the complex transmission line in which the overhead transmission line and the underground transmission line are connected can ensure proper operation in case of failure of the overhead transmission line, but if a failure occurs in the underground transmission line, In this case, the impedance of the cable line is different from that of the overhead line, and an error occurs in the calculation by the algorithm applied to the overhead line due to the change factors of various cable systems. There is a high risk of this, and there is a problem that increases the downtime and recovery costs.

In addition, if an accident occurs in the overhead transmission line of the composite transmission line, it is possible to re-enter and minimize the failure, but it is unclear whether the accident in the overhead transmission line or the underground transmission line is unclear. Because it is not possible to re-enter, there is a huge problem of systematic economic loss because it cannot be re-entered in the event of an accident.

Korean Laid-Open Patent No. 2005-0030489 (Name: Method for protecting a mixed transmission line using a distance relay algorithm)

The present invention has been proposed to solve the above-described problems, and it is determined whether a failure of the underground transmission line and the overhead transmission line occurs based on the fault current detected by the current transformer sensors installed on the main line of the underground transmission line. An object of the present invention is to provide an apparatus and method for detecting a failure of a transmission line for specifying a point of failure in case of a transmission line failure.

In order to achieve the above object, a composite transmission line fault detecting apparatus according to an embodiment of the present invention collects a fault current collecting unit and a fault current collecting unit for collecting fault currents from an input current transformer sensor and an output current transformer sensor installed in an underground transmission line. Fault current synchronizing unit for synchronizing a fault current, current direction detecting unit for detecting the current direction of fault current synchronized in the fault current synchronizing unit, or one of overhead transmission line and underground transmission line based on the current direction detected by the current direction detecting unit Includes a fault section detector for detecting a fault section and a fault location detector for detecting a fault location based on a phase change of the fault current synchronized by the fault current synchronizer when the underground transmission line is detected as a fault section.

The fault current collecting unit collects the first A phase fault current from the first input side current transformer sensor installed at the input side of the main line A phase line of the underground transmission line, and the first current side current transformer sensor installed at the output side of the main line A phase line of the underground transmission line. The first collection module for collecting the second A phase fault current, the first B phase fault current is collected from the second input side current transformer sensor installed at the input side of the main line B phase line of the underground transmission line, and the main line A phase line of the underground transmission line. Collects a first C phase fault current from a second collecting module for collecting a second B phase fault current from a second output side current transformer sensor installed at an output side of a third input side current transformer sensor installed at an input side of a main line C phase line of an underground transmission line. And collecting a second C-phase fault current from a third output side current transformer sensor installed at an output side of the main line A phase line of the underground transmission line. All.

The fault current synchronizer may synchronize fault currents using a synchronization signal output from the GPS satellites, but may synchronize fault currents collected on the same phase.

The fault current synchronizer is a first synchronization module for synchronizing the first A phase fault current and the second A phase fault current collected on the main line A phase line of the underground transmission line, and the first B collected on the main line B phase line of the underground transmission line. A second synchronization module for synchronizing the phase fault current and the second B phase fault current, and a third synchronization module for synchronizing the first C phase fault current and the second C phase fault current collected from the main line C phase line of the underground transmission line. It may include.

The current direction detection unit detects the current direction of the first A phase fault current and the second A phase fault current synchronized in the fault current synchronizer, and the first B phase fault current synchronized in the fault current synchronizer. And a second current direction detection module for detecting a current direction of the second B-phase fault current and a third current direction for detecting current directions of the first C-phase fault current and the second C-phase fault current synchronized by the fault current synchronizer. It may include a detection module.

The failure section detection unit may determine that the underground transmission line is faulty if the current directions of the fault currents measured and synchronized by the input current transformer sensor and the output current transformer sensor coincide with each other.

The fault section detecting unit detects a phase A line of the main line of the underground transmission line as a fault section when the current directions of the first A phase fault current and the second A phase fault current coincide with each other, and the first B phase fault current and the second B phase If the current direction of the fault current coincides, the B-phase line of the main line of the underground transmission line is detected as the fault section, and if the current directions of the 1st phase C fault current and the second C phase fault current coincide, C of the main line of the underground The phase line can be detected as a fault section.

The failure section detector may determine that the overhead transmission line has a failure if the current directions of the synchronized fault currents measured and measured by the input side current transformer sensor and the output side current transformer sensor do not match.

The fault location detector may calculate a fault distance by subtracting a value obtained by multiplying the moving speed of the charge by the fault current detection time difference across the main line from the distance of the bus, and dividing the subtracted value by two.

The fault position detecting unit detects the phase A fault distance based on the phase change of the first phase A fault current and the second phase A fault current, and based on the phase change of the first phase B fault current and the second phase A fault current. The B phase fault distance can be detected, and the C phase fault distance can be detected based on the phase change of the first C phase fault current and the second C phase fault current.

In order to achieve the above object, a method for detecting a fault in a hybrid transmission line according to an exemplary embodiment of the present invention collects fault currents collected from an input current transformer sensor and an output current transformer sensor installed in an underground transmission line. Synchronizing, detecting the current direction of the fault current synchronized in the synchronizing step, and detecting one of the overhead transmission line and the underground transmission line as a fault section based on the current direction detected in the detecting current direction. And detecting a fault location based on a phase change of the fault current synchronized in the synchronizing step when the underground transmission line is detected as the fault section in the detecting in the fault section.

The collecting may include collecting the first A phase fault current and the second A phase fault current from the first input side current transformer sensor and the first output side current transformer sensor installed at both ends of the main line A phase line of the underground transmission line. Collecting the first B-phase fault current and the second B-phase fault current from the second input side current transformer sensor and the second output side current transformer sensor installed on the B phase line of the main line, and the third input side current transformer installed on the C phase line of the underground transmission line. Collecting the first C phase fault current and the second C phase fault current from the sensor and the third output side current transformer sensor.

In the synchronizing step, the fault current may be synchronized using a synchronization signal output from the GPS satellite, but the fault current collected on the same phase may be synchronized.

The synchronizing may include synchronizing the first A phase fault current and the second A phase fault current collected on the main line A phase line of the underground transmission line, and the first B phase fault current collected on the main line B phase line of the underground transmission line. And synchronizing the second B-phase fault current and synchronizing the first C-phase fault current and the second C-phase fault current collected on the main line C-phase line of the underground transmission line.

The detecting of the current direction may include detecting the current directions of the first A-phase fault current and the second A-phase fault current synchronized in the synchronizing step, and the first B-phase fault current and the second B synchronized in the synchronizing step. Detecting the current direction of the phase fault current and detecting the current direction of the synchronized first C phase fault current and the second C phase fault current.

In the step of detecting as a fault section, if the current directions of the fault currents measured and synchronized by the input current transformer sensor and the output current transformer sensor coincide, it may be determined as a failure of the underground transmission line.

In the detecting of the fault section, if the current direction of the first A phase fault current and the second A phase fault current coincides with each other, detecting the A phase line among the main lines of the underground transmission line as the fault section, and the first B phase fault current and Detecting the B-phase line of the main line of the underground transmission line as a failure section if the current direction of the second B-phase fault current coincides; and if the current directions of the first C-phase fault current and the second C-phase fault current coincide, The method may include at least one of detecting a phase C line of the main road as a failure section.

In the step of detecting as a fault section, if the current directions of the fault currents measured and synchronized by the input current transformer sensor and the output current transformer sensor do not coincide, it may be determined as a failure of the overhead transmission line.

In the detecting of the fault location, the fault distance may be calculated by dividing the difference between the distance between the bus and the bus by multiplying the moving speed of the charge by the fault current detection time difference across the main line.

The detecting of the fault location may include detecting the phase A fault distance based on the phase change of the first phase A fault current and the second phase A fault current, and the phases of the first phase B fault current and the second phase A fault current. The method may include at least one of detecting a phase B failure distance based on the change and detecting a phase C failure distance based on a phase change of the first phase C failure current and the second phase C failure current.

According to the present invention, an apparatus and method for detecting a fault in a hybrid transmission line determines whether a failure of an underground transmission line and a overhead transmission line occurs based on fault currents detected by current transformer sensors installed in an underground transmission line, and a failure of an underground transmission line. By specifying the breakdown point at the time, it is possible to identify the breakdown point of the overhead transmission line and the underground transmission line quickly and accurately.

In addition, an apparatus and method for detecting a fault in a composite transmission line is a failure generated in a overhead transmission line if the direction of the fault current measured by the current transformer sensors installed at both ends of the underground transmission line does not match. There is an effect that can be distinguished by a failure in the underground transmission line.

In addition, the apparatus and method for detecting a failure of a composite transmission line has an effect of detecting a failure state and a failure position of each phase of the underground transmission line.

1 and 2 are block diagrams illustrating an apparatus for detecting a fault in a composite transmission line according to an exemplary embodiment of the present invention.
3 is a block diagram illustrating a fault current collecting unit of FIG. 2;
FIG. 4 is a block diagram illustrating the fault current synchronizer of FIG. 2. FIG.
FIG. 5 is a block diagram illustrating the current direction detection unit of FIG. 2. FIG.
6 and 7 are diagrams for explaining the failure position detection unit of FIG.
8 is a flowchart illustrating a method for detecting a failure of a composite transmission line according to an exemplary embodiment of the present invention.
FIG. 9 is a flowchart for explaining a fault interval detecting step of FIG. 8; FIG.

Hereinafter, the most preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the technical idea of the present invention. . First of all, in adding reference numerals to the components of each drawing, it should be noted that the same reference numerals are used as much as possible even if displayed on different drawings. In addition, in describing the present invention, when it is determined that the detailed description of the related well-known configuration or function may obscure the gist of the present invention, the detailed description thereof will be omitted.

First, a composite transmission line to which a composite transmission line failure detection device according to an embodiment of the present invention is applied is a mixture of overhead transmission lines and underground transmission lines, or overhead transmission lines, underground transmission lines, and overhead transmission lines in that order. Or mixed. The underground transmission line and the overhead transmission line may be set in such a manner that they are mixed in order.

The composite transmission line failure detecting device detects whether the underground transmission line and the overhead transmission line that constitute the composite transmission line have failed. At this time, the composite transmission line fault detection apparatus visually synchronizes the phase change of the fault current measured by the input current transformer sensor provided on the input side of the underground transmission line and the output current transformer sensor provided on the output side of the main line. The composite transmission line fault detection device judges that the fault occurred in the overhead transmission line if the phase direction of the time equalized fault current coincides. The composite transmission line fault detection device determines that a failure occurred in the underground transmission line if the phase directions of the time equalized fault currents do not match.

The composite transmission line fault detecting apparatus detects a fault position by using a fault current when determining that the underground transmission line has a fault. At this time, the composite transmission line failure detection device detects a failure distance by comparing and analyzing the GPS time-synchronized data (that is, the failure current). The composite transmission line fault detection device detects a fault position based on the detected fault distance.

Hereinafter, a detailed description will be given of a composite transmission line failure detecting apparatus according to an embodiment of the present invention with reference to the accompanying drawings. 1 is a block diagram illustrating an apparatus for detecting a complex transmission line failure according to an exemplary embodiment of the present invention. 2 is a block diagram illustrating the fault current collecting unit of FIG. 1, FIG. 3 is a block diagram illustrating the fault current synchronizing unit of FIG. 1, and FIG. 4 is a block diagram illustrating the current direction detecting unit of FIG. 1. 5 and 6 are diagrams for describing the fault location detector of FIG. 1.

Referring to FIGS. 1 and 2, the apparatus for detecting a failure of the composite transmission line 100 may include a fault current collector 110, a fault current synchronizer 130, a current direction detector 150, a fault section detector 170, and a fault. The position detector 190 is included.

The fault current collecting unit 110 collects a fault current from the input side current transformer sensor 200 and the output side current transformer sensor 300 installed in the underground power transmission line 440 of the composite power transmission line 400. In this case, the fault current collecting unit 110 collects a fault current from the input side current transformer sensor 200 and the output side current transformer sensor 300 installed on the main line of the underground power transmission line 440. Here, the input current transformer sensor 200 and the output current transformer sensor 300 are installed at both ends of each phase of the main line of the underground transmission line 440.

In order to calculate the more accurate fault location, the phase fault voltage of the phase calculated together with the fault current is required, the fault current collector 110 is the transformer channel of the fault recorder of the corresponding substation in which the master device is installed or the transformer of the bus transformer board. You can also collect in parallel.

For example, in the case of the three-phase underground transmission line 440, the fault current collecting unit 110 may include the first input side current transformer sensor 220 to the third input side current transformer and the first output side current transformer sensor 320 to the third output side current transformer sensor. Collect fault currents from 360.

The first input side current transformer sensor 220 is installed at an input side of the main line A phase line 442 to sense a first A phase fault current. The first output side current transformer sensor 320 is installed at an output side of the main line A phase line 442 to sense a second A phase fault current. The first input current transformer sensor 220 and the first output current transformer sensor 320 transmit the detected first A-phase fault current and the second A-phase fault current to the fault current collector 110.

The second input side current transformer sensor 240 is installed at the input side of the main line B phase line 444 to detect the first B phase fault current. The second output side current transformer sensor 340 is installed at the output side of the main line B phase line 444 to detect the second B phase fault current. The second input current transformer sensor 240 and the second output current transformer sensor 340 transmit the detected first B-phase fault current and the second B-phase fault current to the fault current collector 110.

The third input current transformer sensor 260 is installed at the input side of the main line C-phase line 446 to sense the first C-phase fault current. The third output side current transformer sensor 360 is installed at the output side of the main line C phase line 446 to sense a second C phase fault current. The third input side current transformer sensor 260 and the third output side current transformer sensor 360 transmit the detected first C phase fault current and the second C phase fault current to the fault current collector 110.

The fault current collecting unit 110 transmits a fault current collected from the first input side current transformer sensor 220 to the third output side current transformer sensor 360 to the fault current synchronization unit 130. At this time, the fault current collecting unit 110 includes a phase A fault current (a first A phase fault current and a second A phase fault current), a B phase fault current (a first B phase fault current and a second B phase fault current), and At least one of the phase C fault current (the first C phase fault current and the second C phase fault current) is transmitted to the fault current synchronizer 130.

Referring to FIG. 3, the fault current collector 110 may include a first collection module 112, a second collection module 114, and a third collection module 116.

The first collection module 112 collects the phase A fault current. That is, the first collection module 112 collects the first A phase fault current from the first input side current transformer sensor 220. The first collection module 112 collects a second A phase fault current from the first output side current transformer sensor 320.

The second collection module 114 collects the B phase fault current. That is, the second collection module 114 collects the first B phase fault current from the second input side current transformer sensor 240. The second collection module 114 collects the second B phase fault current from the second output side current transformer sensor 340.

The third collection module 116 collects the C phase fault current. That is, the third collection module 116 collects the first C phase fault current from the third input side current transformer sensor 260. The third collection module 116 collects the second C phase fault current from the third output side current transformer sensor 360.

The fault current synchronizer 130 synchronizes the fault current collected by the fault current collector 110 using the synchronization signal output from the GPS satellites. The fault current synchronizer 130 synchronizes fault currents collected in the same phase among fault currents collected by the fault current collector 110. The fault current synchronizer 130 synchronizes the first A phase fault current and the second A phase fault current. The fault current synchronizer 130 synchronizes the first B-phase fault current and the second B-phase fault current. The fault current synchronizer 130 synchronizes the first C phase fault current and the second C phase fault current.

Referring to FIG. 4, the fault current synchronizer 130 may include a first synchronization module 132, a second synchronization module 134, and a third synchronization module 136.

The first synchronization module 132 synchronizes the phase A fault current received from the first collection module 112. That is, the first synchronization module 132 synchronizes the first A phase high current and the second A phase fault current received from the first collection module 112.

The second synchronization module 134 synchronizes the B phase fault current received from the second collection module 114. That is, the second synchronization module 134 synchronizes the first B-phase high current and the second B-phase fault current received from the second collection module 114.

The third synchronization module 136 synchronizes the phase C fault current received from the third collection module 116. That is, the third synchronization module 136 synchronizes the first C phase high current and the second C phase fault current received from the third collection module 116.

The current direction detector 150 detects the current direction of the fault current synchronized by the fault current synchronizer 130. That is, the current direction detection unit 150 detects current directions of the phase A fault current, the phase B fault current, and the phase C fault current.

Referring to FIG. 5, the current direction detection unit 150 may include a first current direction detection module 152, a second current direction detection module 154, and a third current direction detection module 156.

The first current direction detection module 152 detects the current direction of the phase A fault current synchronized by the first synchronization module 132. That is, the first current direction detection module 152 detects the current directions of the first A phase fault current and the second A phase fault current synchronized by the first synchronization module 132.

The second current direction detection module 154 detects the current direction of the B phase fault current synchronized in the second synchronization module 134. That is, the second current direction detection module 154 detects the current directions of the first B-phase fault current and the second B-phase fault current synchronized by the second synchronization module 134.

The third current direction detection module 156 detects the current direction of the C phase fault current synchronized in the third synchronization module 136. That is, the third current direction detection module 156 detects the current directions of the first C phase fault current and the second C phase fault current synchronized by the third synchronization module 136.

The fault section detector 170 detects a fault section based on the current direction of the fault current detected by the current direction detector 150. The failure section detection unit 170 determines that a failure occurs in any one of the overhead transmission line 420 and the underground transmission line 440 based on the current direction of the failure current.

The failure section detection unit 170 determines that a failure of the underground transmission line 440 occurs when the current directions of the failure currents coincide with each other. That is, when the direction of the first A phase fault current and the second A phase fault current coincides with each other, the fault section detector 170 determines that a fault occurs in the A phase line 442 of the main line of the underground transmission line 440. The failure section detection unit 170 determines that a failure occurs in the B-phase line 444 of the main line of the underground transmission line 440 when the directions of the first B-phase fault current and the second B-phase fault current match. The failure section detection unit 170 determines that a failure occurs in the C-phase line 446 of the main line of the underground transmission line 440 when the directions of the first C-phase fault current and the second C-phase fault current match.

The failure section detection unit 170 determines that a failure of the overhead transmission line 420 occurs when the current direction of the fault current does not match. That is, the failure section detection unit 170 does not coincide with the directions of the first A phase fault current and the second A phase fault current, and the directions of the first B phase fault current and the second B phase fault current do not coincide with each other. If the directions of the 1 C phase fault current and the second C phase fault current do not coincide, it is determined that a failure of the overhead transmission line 420 occurs.

If the fault location detector 190 determines that the underground transmission line 440 is out of order, the fault section detection unit 170 detects the fault location based on the phase change of the fault current synchronized by the fault current synchronizer 130.

The fault location detector 190 detects a fault distance based on a phase change of a fault current generated when a short circuit or a ground fault occurs in a transmission line. The fault location detector 190 calculates a fault distance by using PMU data measured by a phase measurement unit (PMU) of the current transformer sensor.

That is, referring to FIGS. 6 and 7, the same phase is measured at both ends of the transmission line in the absence of an accident, and a phase change (that is, a phase angle change) occurs at both ends of the transmission line in the accident. Phase is measured.

Thus, the fault location detector 190 detects a fault distance based on the phase change of the synchronized fault current. The fault location detector 190 detects a fault distance by using a phase angle change of the fault current and a generation time of the fault current. Here, the generation time of the fault current is the time measured by the GPS time when the fault current occurs.

The fault location detector 190 detects a fault distance of each phase based on a phase change of the fault current of each phase. The fault position detector 190 detects the phase A fault distance based on the phase change between the first phase A fault current and the second phase A fault current. The fault location detector 190 detects the B phase fault distance based on the phase change between the first B phase fault current and the second B phase fault current. The fault position detector 190 detects the C phase fault distance based on a phase change between the first C phase fault current and the second C phase fault current.

As an example, the fault location detector 190 calculates a fault distance by using Equation 1 below. That is, the failure location detection unit 190 simultaneously records the time-tag obtained by GPS time-synchronization of the fault current (that is, PMU data) of high-speed sampling (≥128samples / cycle) with the precision PT / CT of the terminal at the time of failure. Calculate X). The fault location detector 190 calculates the fault distance X by using the time difference t _b -t _a between the ends of the charge with respect to the moving speed C of the charge through the resolution of microsecond (μS) during a transient accident.

Here, X is the failure distance, L is the distance of the bus (distance between the current transformer sensors installed at both ends of the bus), C is the speed of movement of the charge, (t _b -t _a ) means the time difference between both ends.

The fault location detector 190 detects a fault location by using the calculated fault distance and bus length (that is, distance between current transformer sensors installed at both ends of the bus).

Hereinafter, a method of detecting a failure of a composite transmission line 400 according to an exemplary embodiment of the present invention will be described in detail with reference to the accompanying drawings. 8 is a flowchart illustrating a method for detecting a failure of a composite transmission line 400 according to an exemplary embodiment of the present invention.

The fault current collecting unit 110 collects a fault current from a plurality of current transformer sensors installed in the underground transmission line 440 of the composite transmission line 400 (S100). That is, the fault current collecting unit 110 collects a fault current from a plurality of current transformer sensors installed on the main line of the underground power transmission line 440. Here, the plurality of current transformer sensors are installed at each end of each phase of the main line of the underground transmission line 440.

For example, in the case of the three-phase underground transmission line 440, the fault current collecting unit 110 may include the first input side current transformer sensor 220 and the first input side current transformers 220 installed at both ends of the main line A phase line 442 of the underground transmission line 440. 1 Collects the phase A fault current including the first A phase fault current and the second A phase fault current from the output side current transformer sensor 320. The fault current collecting unit 110 includes a first B-phase fault current from the second input side current transformer sensor 240 and the second output side current transformer sensor 340 installed at both ends of the main line B phase line 444 of the underground transmission line 440. And a phase B fault current comprising a second phase B fault current. The fault current collecting unit 110 receives the first C-phase fault current from the third input side current transformer sensor 260 and the third output side current transformer sensor 360 installed at both ends of the main line C phase line 446 of the underground transmission line 440. And collect the C phase fault current including the second C phase fault current. The fault current collector 110 transmits at least one of the collected A-phase fault current, the B-phase fault current, and the C-phase fault current to the fault current synchronizer 130.

The fault current synchronizer 130 synchronizes the fault current using the synchronization signal output from the GPS satellite (S200). That is, the fault current synchronizer 130 synchronizes fault currents collected in the same phase among fault currents collected in step S100. The fault current synchronizer 130 synchronizes the first A phase fault current and the second A phase fault current. The fault current synchronizer 130 synchronizes the first B-phase fault current and the second B-phase fault current. The fault current synchronizer 130 synchronizes the first C phase fault current and the second C phase fault current.

The current direction detection unit 150 detects the current direction of the synchronized fault current (S300). That is, the current direction detection unit 150 detects the current directions of the phase A fault current, the phase B fault current, and the phase C fault current synchronized at step S200.

The failure section detection unit 170 detects the failure section based on the current direction of the failure current (S400). That is, the failure section detection unit 170 determines that a failure occurs in any one of the overhead transmission line 420 and the underground transmission line 440 based on the current direction of the failure current. At this time, the failure section detection unit 170 determines that a failure of the underground transmission line 440 occurs when the current direction of the fault current coincides. The failure section detection unit 170 determines that a failure of the overhead transmission line 420 occurs when the current direction of the fault current does not match.

Referring to FIG. 9, when the directions of the first A phase fault current and the second A phase fault current coincide with each other (410; YES), the fault section detecting unit 170 may check the A phase line (of the main line of the underground transmission line 440). It is determined that the failure of 442 (S420).

If the directions of the first B-phase fault current and the second B-phase fault current coincide with each other (430; YES), the fault section detecting unit 170 may cause a failure of the B-phase line 444 in the main line of the underground power transmission line 440. It is determined (S440).

If the directions of the first C phase fault current and the second C phase fault current coincide (450; YES), the fault section detecting unit 170 may cause a failure of the C phase line 446 of the main line of the underground transmission line 440. It is determined (S460).

The failure section detection unit 170 does not match the directions of the first A-phase fault current and the second A-phase fault current, and does not match the directions of the first B-phase fault current and the second B-phase fault current, and the first C If the directions of the phase fault current and the second C phase fault current do not coincide with each other, it is determined that a failure of the overhead transmission line 420 occurs (S470).

If it is determined in step S400 that the underground transmission line 440 has a failure (S500; yes), the failure location detection unit 190 detects the failure location based on the phase change of the synchronized failure current (S600). That is, the fault location detector 190 detects a fault distance by using a phase angle change of the fault current and a generation time of the fault current. Here, the generation time of the fault current is the time measured by the GPS time when the fault current occurs.

The fault location detector 190 detects a fault distance of each phase based on a phase change of the fault current of each phase. The fault position detector 190 detects the phase A fault distance based on the phase change between the first phase A fault current and the second phase A fault current. The fault location detector 190 detects the B phase fault distance based on the phase change between the first B phase fault current and the second B phase fault current. The fault position detector 190 detects the C phase fault distance based on a phase change between the first C phase fault current and the second C phase fault current.

The fault location detector 190 calculates a fault distance by using the distance between the bus bar, the moving speed of the charge, and the time difference between both ends. The fault location detector 190 calculates a fault distance by dividing the difference between the distance of the bus and the value obtained by multiplying the moving speed of the charge and the time difference between both ends. The fault location detector 190 detects a fault location by using the calculated fault distance and bus length (that is, distance between current transformer sensors installed at both ends of the bus).

As described above, the apparatus and method for detecting a failure of a composite transmission line determines whether a failure of the underground transmission line and the overhead transmission line occurs based on the fault current detected by the current transformer sensors installed in the underground transmission line, and the failure of the underground transmission line. By specifying the breakdown point at the time, it is possible to identify the breakdown point of the overhead transmission line and the underground transmission line quickly and accurately.

In addition, an apparatus and method for detecting a fault in a composite transmission line is a failure generated in a overhead transmission line if the direction of the fault current measured by the current transformer sensors installed at both ends of the underground transmission line does not match. There is an effect that can be distinguished by a failure in the underground transmission line.

In addition, the apparatus and method for detecting a failure of a composite transmission line has an effect of detecting a failure state and a failure position of each phase of the underground transmission line.

Although a preferred embodiment according to the present invention has been described above, modifications can be made in various forms, and those skilled in the art may make various modifications and modifications without departing from the scope of the claims of the present invention. It is understood that it may be practiced.

100: fault detection device for the complex transmission line 110: fault current collector
130: fault current synchronization unit 150: current direction detection unit
170: failure section detection unit 190: failure location detection unit
200: input current transformer sensor 300: output current transformer sensor
400: composite transmission line 420: overhead transmission line
440 underground transmission line

Claims (20)

In the composite transmission line failure detection device for detecting a failure in the composite transmission line mixed with overhead transmission line and underground transmission line,
A fault current collector configured to collect fault currents from an input current transformer sensor and an output current transformer sensor installed on a main line of the underground transmission line;
A fault current synchronizer configured to synchronize fault currents collected by the fault current collector;
A current direction detector for detecting a current direction of the fault current synchronized by the fault current synchronizer;
A fault section detector for detecting one of the overhead transmission line and the underground transmission line as a fault section based on the current direction detected by the current direction detector; And
When the fault section detection unit detects the underground transmission line as a fault section includes a fault location detector for detecting a fault location based on the phase change of the fault current synchronized by the fault current synchronization unit,
The fault position detecting unit detects a fault distance based on a phase change between a first fault current collected by the input side current transformer sensor and a second fault current collected by the output side current transformer sensor. The method of claim 1,
The fault current collector,
A first A phase fault current is collected from a first input side current transformer sensor provided at an input side of the main line A phase line of the underground transmission line, and a second output current transformer current sensor installed at an output side of the main line A phase line of the underground transmission line from a second output current sensor. A first collecting module collecting the phase A fault current;
A first B phase fault current is collected from a second input side current transformer sensor provided at an input side of a main line B phase line of the underground transmission line, and a second output side current transformer sensor installed at an output side of a main line A phase line of the underground transmission line is connected to a second. A second collecting module collecting the B phase fault current; And
A first C phase fault current is collected from a third input side current transformer sensor provided on an input side of a main line C phase line of the underground transmission line, and a second output side current transformer sensor installed on an output side of a main line A phase line of the underground transmission line. Complex transmission line failure detection device comprising a third collection module for collecting the C-phase fault current. The method of claim 1,
The fault current synchronization unit is a composite transmission line fault detection device for synchronizing the fault current using the synchronization signal output from the GPS satellite, but the fault current collected on the same phase. The method of claim 1,
The fault current synchronization unit,
A first synchronization module for synchronizing the first A phase fault current and the second A phase fault current collected from the main line A phase line of the underground transmission line;
A second synchronization module configured to synchronize the first B-phase fault current and the second B-phase fault current collected from the main line B-phase line of the underground transmission line; And
And a third synchronization module for synchronizing the first C phase fault current and the second C phase fault current collected from the main line C phase line of the underground transmission line. The method of claim 1,
The current direction detection unit
A first current direction detection module configured to detect current directions of the first A-phase fault current and the second A-phase fault current synchronized by the fault current synchronizer;
A second current direction detection module detecting current directions of the first B-phase fault current and the second B-phase fault current synchronized by the fault current synchronization unit; And
And a third current direction detection module configured to detect current directions of the first C phase fault current and the second C phase fault current synchronized by the fault current synchronization unit. The method of claim 1,
The failure section detection unit,
The composite transmission line fault detection apparatus for determining that the underground transmission line failure if the current direction of the fault currents measured and synchronized by the input current transformer sensor and the output current transformer sensor match. The method of claim 1,
The failure section detection unit,
If the current directions of the first A phase fault current and the second A phase fault current coincide with each other, the A phase line of the main line of the underground transmission line is detected as a fault section,
If the current directions of the first B-phase fault current and the second B-phase fault current coincide, the B-phase line of the main line of the underground transmission line is detected as a fault section,
The composite transmission line fault detecting apparatus for detecting a phase C line of the main line of the underground transmission line as a failure section when the current directions of the first C phase fault current and the second C phase fault current coincide. The method of claim 1,
The failure section detection unit,
The composite transmission line fault detection apparatus for determining the failure of the overhead transmission line if the current direction of the fault currents measured and synchronized by the input current transformer sensor and the output current transformer sensor do not match. The method of claim 1,
The fault location detection unit is a complex transmission line fault detection apparatus for subtracting the value multiplied by the moving speed of the charge and the fault current detection time difference across the main line from the distance of the bus, and dividing the subtracted value to calculate the fault distance. The method of claim 1,
The fault location detection unit,
Detect the phase A fault distance based on the phase change of the first phase A fault current and the second phase A fault current,
Detect the phase B failure distance based on the phase change of the first phase B fault current and the second phase A fault current,
A composite transmission line fault detection apparatus for detecting a phase C fault distance based on a phase change of a first phase C fault current and a second phase C fault current. In the composite transmission line failure detection method for detecting a failure in a composite transmission line mixed with overhead transmission line and underground transmission line,
Collecting fault currents from an input current transformer sensor and an output current transformer sensor installed on a main line of the underground transmission line;
Synchronizing the fault current collected in the collecting step;
Detecting a current direction of the fault current synchronized in the synchronizing;
Detecting one of the overhead transmission line and the underground transmission line as a failure section based on the current direction detected in the detecting of the current direction; And
Detecting the fault location based on a phase change of the fault current synchronized in the synchronizing step when the underground transmission line is detected as the fault section in the detecting of the fault section,
And detecting the fault location based on a phase change between a first fault current collected by the input current transformer sensor and a second fault current collected by the output current transformer sensor. The method of claim 11,
The collecting step,
Collecting a first A phase fault current and a second A phase fault current from a first input side current transformer sensor and a first output side current transformer sensor provided at both ends of the main line A phase line of the underground transmission line;
Collecting a first B phase fault current and a second B phase fault current from a second input side current transformer sensor and a second output side current transformer sensor installed on a main line B phase line of the underground transmission line; And
And collecting a first C phase fault current and a second C phase fault current from a third input side current transformer sensor and a third output side current transformer sensor installed on a main line C phase line of the underground transmission line. The method of claim 11,
In the synchronizing step, a fault current is synchronized using a synchronization signal output from a GPS satellite, but a fault is detected in the combined transmission line. The method of claim 11,
Synchronizing is,
Synchronizing a first A phase fault current and a second A phase fault current collected in the main line A phase line of the underground transmission line;
Synchronizing a first B-phase fault current and a second B-phase fault current collected from the main line B-phase line of the underground transmission line; And
And synchronizing the first C phase fault current and the second C phase fault current collected from the main line C phase line of the underground transmission line. The method of claim 11,
Detecting the current direction,
Detecting current directions of the first A phase fault current and the second A phase fault current synchronized in the synchronizing step;
Detecting current directions of the first B-phase fault current and the second B-phase fault current synchronized in the synchronizing step; And
And detecting at least one of a current direction of the first C-phase fault current and the second C-phase fault current synchronized in the synchronizing step. The method of claim 11,
In the detecting step of the fault section, if the current direction of the fault currents measured and synchronized by the current-side current transformer sensor and the output-current current transformer sensor match, it is determined that the underground transmission line failure. The method of claim 11,
In the detecting step as the failure section,
Detecting a phase A line of the main line of the underground transmission line as a failure section when the current directions of the first phase A fault current and the second phase A fault current coincide;
Detecting a phase B line of the main line of the underground transmission line as a failure section when the current directions of the first phase B fault current and the second phase B fault current coincide; And
And detecting at least one C-phase line of the main line of the underground transmission line as a failure section when the current directions of the first C-phase fault current and the second C-phase fault current coincide with each other. The method of claim 11,
In the detecting step as the failure section,
And detecting a failure of the overhead transmission line if the current directions of the synchronized fault currents measured and synchronized by the input current transformer sensor and the output current transformer sensor do not match. The method of claim 11,
In the step of detecting the fault location, the fault transmission method for calculating the fault distance by dividing the difference of the distance between the bus and the distance multiplied by the multiplied by the moving speed of the charge and the fault current detection time difference across the main line. The method of claim 11,
Detecting the fault location,
Detecting a phase A fault distance based on a phase change of the first phase A fault current and the second phase A fault current;
Detecting a phase B fault distance based on a phase change of the first phase B fault current and the second phase A fault current; And
And detecting at least one phase C fault distance based on a phase change of the first phase C fault current and the second phase C fault current.

Images