KR20230117955A - The method and device of monitoring/control panel to interlock circuit breaker from closing when transmission line is grounded - Google Patents

Abstract

A method for preventing grounding of a power transmission line by a monitoring and control panel of the present invention includes the steps of recording line induced voltage information during a power failure of a power transmission line managed by the monitoring and control panel; checking whether the transmission line is switched to a power failure state; Recognizing an input schedule of the transmission line; measuring the voltage of the power transmission line and comparing it with the recorded line induced voltage information during power failure; if the measured voltage of the transmission line belongs to a predetermined reference ratio range with respect to the line-induced voltage information, allowing the transmission line to be closed, considering that the transmission line is grounded; and if the measured voltage of the power transmission line does not fall within a predetermined reference ratio range for the line-induced voltage information, blocking the power transmission line as being in a grounded state, and preventing the power transmission line from being turned on.

Description

Method and device for preventing line pressurization during grounding of power transmission line of monitoring and control panel

The present invention utilizes the status, measurement, and calculation points of the monitoring and control panel to detect the grounding state of the transmission line, and in the state where the line is grounded, the power transmission line breaker (e.g., Transmission Line Circuit Breaker) is inserted and pressurized. It relates to a method and device for preventing pressurization in a grounded state for preventing failure.

In the case of grounding using a grounding switch during transmission line grounding, it is possible to grasp it through the status display of the monitoring and control panel, but in the case of grounding using the grounding wire in the middle of the transmission line, workers at the power plant and substation cannot grasp it through the monitoring and control panel system. That is, at the time of first pressurization after a power outage, a circuit breaker is operated as a method of verbally checking the ground removal state between a worker and an operator.

Although the magnitude of the induced voltage can be checked using the relay's measurement system, it is not possible to determine how much the induced voltage value is in the ground state. Although there is a prior art for detecting grounding in a method of detecting induced voltage with measurement data of a protection relay, not a supervisory control panel, there is a prior art, but the induced voltage value is corrected (using the status, measurement, and calculation points of the supervisory control panel) Setting) and failure prevention technology" was not presented.

Therefore, in order to determine the grounding of the grounded line and to prevent the circuit breaker from being pressurized, the monitoring and control panel's measurement accuracy and resolution have been advanced, suggesting a way to detect the grounding state by using measurement, calculation, and setting points like protection relays. do.

Republic of Korea Publication No. 10-2009-0047909

An object of the present invention is to provide a method and apparatus for preventing line pressurization during grounding of a power transmission line capable of preventing pressurization of a circuit breaker (CB) of a corresponding line in a monitoring and control panel in a state in which the grounding of the power-off line is not released.

A method for preventing line pressurization during power transmission line grounding by a monitoring and control panel according to an aspect of the present invention includes the steps of recording line induced voltage information during a power failure of a power transmission line managed by the monitoring and control panel; checking whether the transmission line is switched to a power failure state; Recognizing an input schedule of the transmission line; measuring the voltage of the power transmission line and comparing it with the recorded line induced voltage information during power failure; if the measured voltage of the transmission line belongs to a predetermined reference ratio range with respect to the line-induced voltage information, allowing the transmission line to be closed, considering that the transmission line is grounded; and if the measured voltage of the power transmission line does not fall within a predetermined reference ratio range for the line-induced voltage information, blocking the power transmission line as being in a grounded state, and preventing the power transmission line from being turned on.

Here, the transmission line is a three-phase AC power line, and the line induced voltage information during power failure may be provided for each power failure combination of each phase line of the three-phase AC power line.

Here, the step of recording the line induced voltage information during power failure of the power transmission line, when each power failure combination of the three-phase AC power line occurs according to a separate test or power failure work, the three-phase AC in the power failure combination. It may be performed by recording line induced voltage information when a power line is out of power.

Here, measuring the voltage of the transmission line may be performed with respect to the transmission line located at the place where the monitoring and control panel is installed.

Here, the step of confirming the transition of the power failure state of the power transmission line includes: checking a voltage change of the power transmission line according to the ground connection of the power transmission line; and checking a voltage change of the power transmission line according to the transition of the power failure state of the power transmission line after connecting the ground.

Here, in the step of confirming the transition of the power failure state of the transmission line, whether or not the power failure state is switched by a pre-recorded power failure task for the power transmission line, and in the step of recognizing the scheduled turn-on of the transmission line, the pre-recorded In the case of a transition to a cease-fire state due to a cease-fire work, the corresponding transmission line can be recognized as scheduled for input.

An apparatus for preventing line pressurization during grounding of a power transmission line according to another aspect of the present invention includes an induced voltage information recording unit for recording line induced voltage information during a power outage of a power transmission line managed by a monitoring and control panel; a transmission line monitoring unit that checks a power failure state transition of the transmission line from the voltage measured for the transmission line, and recognizes an input schedule of the transmission line; a ground determination unit that compares the measured voltage of a transmission line in a power failure state with the recorded line induced voltage information during power failure to determine whether or not the power transmission line to be connected is grounded; and a grounding action unit allowing input to the transmission line when it is determined that grounding is released.

Here, the ground determination unit determines that the transmission line is grounded when the measured voltage of the transmission line falls within a predetermined reference ratio range with respect to the line-induced voltage information, and determines that the measured voltage of the transmission line is the line-induced voltage information. If the voltage information does not fall within a predetermined reference ratio range, it may be determined as the ground state of the transmission line.

Here, the transmission line is a three-phase AC power line, and the line-induced voltage information recording unit, when each power failure combination of the three-phase AC power line is generated according to a separate test or power failure work, the power failure combination It is possible to record line induced voltage information during power failure for each power failure combination in a manner of recording line induced voltage information during power failure of a three-phase AC power line.

Here, a PT for measuring the voltage of the transmission line located at the place where the monitoring and control panel is installed may be further included.

Here, the power transmission line monitoring unit may check the voltage change of the power transmission line according to the ground connection of the specific power transmission line, and check the voltage change of the power transmission line according to the power failure state transition of the power transmission line after the ground connection.

Here, the power transmission line monitoring unit checks whether or not the power failure state is switched by a pre-recorded power failure task with respect to a specific power transmission line, and if the power failure state is switched by the pre-recorded power failure task, the transmission line is recognized as scheduled to be turned on. can do.

If a method and/or device for preventing line pressurization during grounding of a power transmission line of a monitoring and control panel according to the spirit of the present invention having the above configuration is implemented, pressurization of the circuit breaker of the corresponding line is prevented in advance in a state in which the grounding of the power-off line is not released. There are benefits you can do.

Specifically, the method and/or device for preventing line pressurization during transmission line grounding of the monitoring and control panel of the present invention determines grounding or foreign object contact that is not visually confirmed on the line or steel tower after working on the transmission line, thereby grounding when the transmission line is pressurized. There is an advantage in preventing failure due to non-removal.

The method and/or device for preventing line pressurization during transmission line grounding of the monitoring and control panel of the present invention can determine the grounded state of the line before the transmission line is pressurized by the measured value of the induced voltage, and the worker can compare it with the set value, When the induced voltage is lower than the set value, the input is blocked and the worker can be notified. Since grounding can be detected at the substation monitoring and control panel on both sides of the transmission line, there is an advantage of performing 100% detection even in a slightly grounded state.

The method and/or device for preventing line pressurization during transmission line grounding of the monitoring and control panel of the present invention has an advantage of preventing damage compensation to consumers due to power quality deterioration and system ripple due to line pressurization failure during transmission line grounding.

The method and/or device for preventing line pressurization during power transmission line grounding of the monitoring and control panel of the present invention has an advantage in that the foot and substation workers can monitor the grounding state of the transmission line in real time before powering up.

1 is a structural diagram showing a connection relationship on a transmission line of a monitoring and control panel performing a method for preventing grounding of a transmission line according to the spirit of the present invention.
FIG. 2 is a flowchart illustrating an embodiment of a method for preventing grounding of a power transmission line according to the spirit of the present invention, which can be performed in the monitoring and control panel of FIG. 1;
Figure 3 is a block diagram showing an embodiment of an apparatus for performing a method for preventing grounding of a power transmission line according to the spirit of the present invention.
4 and 5 are output screens of a user interface illustrating a state in which steps S110 and S115 of FIG. 2 are performed.
6 to 8 are output screens of a user interface illustrating processes of checking whether or not grounding is released before a circuit breaker is turned on for a transmission line in a power-off state.

In describing the present invention, terms such as first and second may be used to describe various components, but the components may not be limited by the terms. Terms are only for the purpose of distinguishing one element from another. For example, a first element may be termed a second element, and similarly, a second element may be termed a first element, without departing from the scope of the present invention.

When a component is referred to as being connected or connected to another component, it may be directly connected or connected to the other component, but it may be understood that another component may exist in the middle. .

Terms used in this specification are only used to describe specific embodiments, and are not intended to limit the present invention. Singular expressions may include plural expressions unless the context clearly dictates otherwise.

In this specification, the terms include or include are intended to designate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, and one or more other features or numbers, It can be understood that the presence or addition of steps, operations, components, parts, or combinations thereof is not precluded.

In addition, shapes and sizes of elements in the drawings may be exaggerated for clearer description.

Even during a power outage, in the actual field, induction voltage unique to each transmission line exists. In the present invention, this is set in the status, measurement, and calculation points of the monitoring and control panel to determine the grounding state of the power supply line after the power failure is completed to make it normal. We propose a method to prevent a failure by allowing back pressurization and blocking input when grounding is detected.

Even after a power outage in a transmission line, a certain portion of the parallel line induced voltage and the voltage between poles of a circuit breaker are applied to the transformer (Potential Transformer) on the transmission line, so that the induction voltage unique to each transmission line remains. By setting in the calculation point, after the power failure is completed, the grounding state of the line before the power supply is judged, and if it is normal, the power supply is allowed.

1 is a structural diagram showing a connection relationship on a transmission line of a monitoring and control panel performing a method for preventing grounding of a transmission line according to the spirit of the present invention.

1 shows a monitoring and control panel 100 in the form of controlling a circuit breaker 10 for a three-phase transmission line of a remote substation. A method for preventing grounding of a power transmission line according to the spirit of the present invention can be implemented.

The illustrated supervisory control panel 100 is provided on a line portion located at the place where the supervisory control panel 100 is installed, and from the measured value of the PT 20 for detecting the voltage of each phase of the three-phase transmission line, the remote Determine the condition of the transmission line at the substation location.

Although the monitoring and control panel 100 is not shown, it is a general monitoring and control panel for receiving necessary sensor measurement values, instructing the operation of devices (eg, switches such as CBs) installed in a remote substation, and providing necessary information to a manager. It may have a user interface (UI).

FIG. 2 is a flowchart illustrating an embodiment of a method for preventing grounding of a power transmission line according to the spirit of the present invention, which can be performed in the monitoring and control panel of FIG. 1. Referring to FIG.

The illustrated method for preventing grounding of a power transmission line by a monitoring and control panel includes the steps of recording line induced voltage information during a power failure of a power transmission line managed by the monitoring and control panel (S110); Checking whether the transmission line is switched to a power failure state (S120); Recognizing an input schedule of the transmission line (S125); Measuring the voltage of the power transmission line and comparing it with the recorded line induced voltage information during power failure (S140); If the measured voltage of the transmission line falls within a predetermined reference ratio range with respect to the line-induced voltage information, allowing the transmission line to be closed, considering that the transmission line is grounded (S160); and

If the measured voltage of the transmission line does not belong to a predetermined reference ratio range with respect to the line-induced voltage information, the transmission line may be considered to be in a ground state, and preventing the transmission line from being turned on (S170). .

In the illustrated flowchart, after step S110 and before step S120, a step (S115) of setting ground release criteria according to a manager's designation or default is further included.

As a criterion for determining ground release in step S115, a reference ratio for line induced voltage during power failure, such as 70% to 100% of the recorded line induced voltage, may be set.

Here, the transmission line is a three-phase AC power line, and the line induced voltage information during power failure in step S110 may be given for each power failure combination of each phase line of the three-phase AC power line.

As mentioned above, the reason why the induced voltage is measured on the transmission line during the power failure is that even after the power failure, the induced voltage of the parallel line and the voltage between poles of the circuit breaker are applied to the transformer (Potential Transformer) to some extent, which is a kind of unique induction for each transmission line. This is because it appears in the form of voltage (induction voltage).

Accordingly, the unique induced voltage for each transmission line appears differently on a case-by-case basis depending on the environment of the place where the transmission line is installed or depending on the type of installation, making it difficult to predict according to certain rules or formulas. do. Therefore, rather than calculating and applying the induced voltage of the transmission line as a standard for grounding determination with a certain rule or formula, a manager or a measurement control device measures the line induced voltage during a power failure of the transmission line as shown in step S110 and determines this. It is desirable to record separately.

In addition, the effect of the line induced voltage during power failure due to the above-mentioned parallel line induced voltage is, when only one or two phases in a three-phase AC transmission line are out of power, each combination of three phases for power failure / non-power failure, transmission of the same phase Even lines have line induced voltages during other interruptions.

Considering the above circumstances, the step of recording the line-induced voltage information during power failure of the power transmission line (S110), when each power failure combination of the three-phase AC power line occurs according to a separate test or power failure work, the corresponding It may be performed by recording line induced voltage information during a power failure of the three-phase AC power line in the power failure combination.

Here, line induced voltage information during power failure may be recorded as a voltage value in units of V, or may be recorded as a ratio (%) to a normal transmission voltage.

On the other hand, looking at the power failure method for the transmission line for performing the step (S110) of recording the line induced voltage information during power failure of the transmission line, all three phases of the three-phase AC power line described above during a separate test time. Alternatively, it is performed by creating a truce situation in the field for each truce combination for some truce and measuring the induced voltage of the corresponding transmission line, or all or part of the three phases of the three-phase AC power line described above actually during the operation of the field. Whenever an armistice situation occurs, it can be performed in a way that records it on the fly.

Meanwhile, when a monitoring and control panel is installed in the form shown in FIG. 1, measuring the voltage of the transmission line can be performed by the PT 10 in FIG. 1 for the transmission line located at the place where the monitoring and control panel is installed. there is.

In general, a power failure operation for a power transmission line first turns off the corresponding line immediately after grounding the corresponding line, and depending on the implementation, when line voltage fluctuations occur according to the order of operations, it may be recognized as a power failure state transition.

In the step of checking the power failure state transition of the power transmission line according to the above implementation (S120), checking the voltage change of the power transmission line according to the ground connection of the power transmission line; and checking a voltage change of the power transmission line according to the transition of the power failure state of the power transmission line after connecting the ground.

Depending on the implementation, in the step of checking the transition of the power failure state of the power transmission line (S120), it is possible to check whether or not the power failure state has been switched by a pre-recorded power failure task for the power transmission line. At this time, with respect to the work of interrupting only a part of the three-phase line, it is also possible to check whether the three-phase line power failure combination described in the scheduled power failure work matches.

In addition, in this case, as illustrated, in the step of recognizing the planned input of the transmission line (S125), when the power failure state is switched by the pre-recorded power failure work, the corresponding transmission line may be recognized as scheduled to be input. This is in consideration of the fact that it will be clear that the ceasefire will be lifted again when the work is completed. On the other hand, if there is no pre-recorded cessation task corresponding to the transition to the cessation state checked in step S120, a manager or the like may be notified (warned) that the cessation state has been unexpectedly switched (S130).

When the supervisor (user) of the supervisory control panel selects a transmission line point (usually a CB installation point) to consider closing on the screen, the voltage of the transmission line is measured and compared with the recorded line induced voltage information during power failure A step (S140) may be performed.

In the illustrated flowchart, after the step S170, a step (S180) of warning (notifying) a manager to remove the ground connection for the transmission line is further included, and then the step S140 can be performed again after removing the ground connection. .

2 is a specific procedure for pressurizing the circuit breaker in order to pressurize the transmission line in the monitoring and control panel, and the method for preventing grounding of the transmission line according to the present invention is embodied. For example, when selecting the circuit breaker control of the corresponding line to operate the closing operation, the unique induced voltage of the line is pre-set, and if the induced voltage is 70% or more of the set value, it is determined that the circuit breaker is grounded, and the closing command process proceeds, and the induced voltage of each phase of the line is determined. When this set value is 70% or less, it is judged as grounding, and the circuit breaker closing command is stopped, and at the same time, it is possible to follow the flow of generating a grounding status confirmation alarm to the worker. In addition, in the illustrated flowchart, in order to apply the grounding determination algorithm, the induced voltage for each line may be measured before powering up and set at a control panel status point.

3 is a block diagram illustrating an embodiment of an apparatus for performing a method for preventing grounding of a power transmission line according to the spirit of the present invention. For example, the transmission line grounding prevention device of FIG. 3 may be applied as an internal HW/SW module or application program of the monitoring and control panel 100 of FIG. 1 .

The illustrated power transmission line grounding prevention device includes an induced voltage information recording unit 120 for recording line induced voltage information during a power failure of a power transmission line managed by a monitoring and control panel; a transmission line monitoring unit 110 that confirms a power failure state transition of the transmission line from the voltage measured for the transmission line and recognizes an input schedule of the transmission line; a ground determination unit 140 that determines whether the power transmission line to be connected is grounded by comparing the measured voltage of the power failure state with the recorded line induced voltage information during power failure; and a ground action unit 160 allowing input to the transmission line when it is determined that grounding is released.

The ground determination unit 140 determines that the transmission line is grounded when the measured voltage of the transmission line falls within a predetermined reference ratio range with respect to the line-induced voltage information, and determines that the measured voltage of the transmission line is the grounding of the transmission line. If the line induced voltage information does not fall within a predetermined reference ratio range, it may be determined that the transmission line is in a grounded state. The predetermined ratio may be set to, for example, 70% to 100% of the recorded line induced voltage.

As described above, the transmission line is generally a three-phase AC power line, and in this case, the line induced voltage information recording unit 120 records each of the three-phase AC power lines according to a separate test or power failure work. When a power failure combination is generated, line induced voltage information during power failure for each power failure combination may be recorded in the storage unit 150 in a manner in which line induced voltage information during power failure of the three-phase AC power line in the power failure combination is recorded.

In FIG. 1, the PT 10 is provided at the place where the monitoring and control panel 100 is installed. Depending on the point of view, the PT 10 for measuring the voltage of the transmission line located at the place where the monitoring and control panel 100 is installed ) can be considered to include more.

For example, the transmission line monitoring unit 110 receives a voltage measurement value from the PT 10, checks the voltage variation of the transmission line according to the ground connection of a specific transmission line, and after connecting the ground, It is possible to check the voltage variation of the power transmission line according to the power failure state transition.

For example, the power transmission line monitoring unit 110 checks whether or not the power failure state has been switched by a power failure job pre-recorded in the storage unit 150 for a specific power transmission line, and the power failure state by the pre-recorded power failure task. In the case of conversion, the corresponding transmission line may be recognized as an input schedule.

In the illustrated transmission line grounding prevention device, the manager of the monitoring and control panel 100 provides on-screen operating means (controls) used to record induced voltage information, and the grounding action unit 160 outputs A user interface 190 outputting a warning (alarm) message may be further included.

According to the above-described method/device for preventing grounding of power transmission lines according to the spirit of the present invention, the induced voltage of a power-off line is utilized by utilizing the calculation algorithm and setting function like a protection relay by utilizing the measurement, status, and calculation functions of the monitoring and control panel. It is possible to clearly determine the grounded state and the released state by measuring and detecting the state change. For example, by adding an algorithm function in software to the monitoring and control panel 100 of FIG. 1, inputting a unique value of induced voltage for each line, setting a voltage value when grounded, grounding detection, and interlocking functions can be added to prevent voltage failure when grounding. .

4 and 5 illustrate an output screen of the user interface 190 of FIG. 3 performing steps S110 and S115 of FIG. 2 .

FIG. 4 is a screen for performing step S110 of FIG. 2, and includes means for adding a ground determination flag and inputting a correction value to a state point of the monitoring control panel. With respect to the illustrated user interface screen, the manager of the monitoring and control panel may perform input of cut-off point numbers of each phase and input of grounding determination.

For example, by utilizing the status point window of the supervisory control panel shown in FIG. 4, a check flag for determining grounding is additionally generated and an address for point grounding detection for each phase of the power transmission line is assigned to the point. In addition, it is possible to input the breaker subject to control of the line and whether or not to be alarmed.

FIG. 5 illustrates a screen for setting a voltage unit scale voltage setting value at the measurement point of the supervisory control panel in step S115 of FIG. 2 . That is, FIG. 5 is a user interface screen for inputting an induced voltage during a power failure for each point number.

For example, on the screen of FIG. 5, input the basic information of the measurement font of the address entered at each phase point in FIG. 4, but enter the point number, transmission line name and phase, unit, scale, etc. It can be registered at 70% of the reference value. In the illustrated example, the ratio is set to 70% of the recorded line induced voltage during power failure, that is, the set criterion is set to ground release if it is 70% or more, and ground alarm alarm if it is less.

6 to 8 illustrate output screens of the user interface 190 of FIG. 3 during the processes of checking whether or not grounding is released before a circuit breaker is turned on for a transmission line in a power-off state.

6 is a user interface screen for permitting the closing of a circuit breaker when an induced voltage value is higher than a basic setting value.

For example, in the screen of FIG. 6, when the control point of the circuit breaker is clicked to pressurize the power failure line, if the induced voltages of all three phases are 70% or more of the set value, it is determined that the ground has been removed and the circuit breaker closing command control point is set. It is activated and manipulation is allowed. As indicated by the box, it is possible to check whether the induced voltage of each phase is normally measured through a pop-up, and it is possible to compare the corrected value and actual value of the unique induced voltage.

7 is a user interface screen that outputs a pop-up to confirm that the ground is not removed when the induced voltage value of one phase (phase A) is less than the set value. pop-up and throw-in)

For example, in the screen of FIG. 7, when the unique induced voltage setting value is 65% for phase A and 100% for phases B and C, it is judged as ground when the induced voltage is measured. outputs a pop-up message, and with this, the circuit breaker is locked so that manipulation is not allowed, and the measured value can be displayed to check the actual induced voltage value of each phase.

Figure 8 is a user interface screen for grounding alarm and shut-off when the induced voltage value is less than the set value of one phase (C phase) of the three phases. stop pop-ups and throws)

For example, as shown in FIG. 8, when the induced voltages of 88% of the A phase, 77% of the B phase, and 69% of the C phase are applied, the induced voltage value of the C phase is 70% or less of the input value and goes to ground. With judgment grounding alarm notification, circuit breaker operation is locked so that it is not allowed, and the measured value can be displayed to check the actual induced voltage value of each phase.

Those skilled in the art to which the present invention pertains should understand that the embodiments described above are illustrative in all respects and not limiting, since the present invention can be embodied in other specific forms without changing the technical spirit or essential characteristics thereof. only do The scope of the present invention is indicated by the claims to be described later rather than the detailed description, and all changes or modifications derived from the meaning and scope of the claims and equivalent concepts should be construed as being included in the scope of the present invention. .

100: monitoring control panel
110: transmission line monitoring unit
120: induced voltage information recording unit
140: ground determination unit
150: storage unit
160: grounding measure
190: user interface

Claims (12)

Recording line induced voltage information during a power failure of a power transmission line managed by a monitoring and control panel;
checking whether the transmission line is switched to a power failure state;
Recognizing an input schedule of the transmission line;
measuring the voltage of the power transmission line and comparing it with the recorded line induced voltage information during power failure;
if the measured voltage of the transmission line belongs to a predetermined reference ratio range with respect to the line-induced voltage information, allowing the transmission line to be closed, considering that the transmission line is grounded; and
If the measured voltage of the transmission line does not belong to a predetermined reference ratio range with respect to the line-induced voltage information, the transmission line is considered to be in a ground state, and blocking the transmission line from being turned on.
A method for preventing line pressurization during grounding of a transmission line of a monitoring and control panel comprising a.
According to claim 1,
The transmission line is a three-phase AC power line,
The line induced voltage information during power failure,
A method for preventing line pressurization during grounding of a transmission line of a monitoring and control panel given for each power failure combination of each phase line of the three-phase AC power line.
According to claim 2,
The step of recording line induced voltage information during a power outage of the transmission line,
When each power failure combination of the three-phase AC power line occurs according to a separate test or power failure work, the monitoring and control panel is performed by recording line induced voltage information during power failure of the three-phase AC power line in the corresponding power failure combination. A method for preventing line pressurization during grounding of power transmission lines.
According to claim 1,
Measuring the voltage of the transmission line is performed for the transmission line located in the place where the monitoring and control panel is installed.
According to claim 4,
In the step of confirming the power failure state transition of the transmission line,
Checking a voltage change of the transmission line according to the ground connection of the transmission line; and
Checking the voltage change of the transmission line according to the transition of the power failure state of the transmission line after ground connection
A method for preventing line pressurization during grounding of a transmission line of a monitoring and control panel comprising a.
According to claim 1,
In the step of confirming the power failure state transition of the transmission line,
Check whether the power failure state is switched by a pre-recorded power failure work for the transmission line;
In the step of recognizing the input schedule of the transmission line,
In the case of a power failure state transition by the pre-recorded power failure work, a method for preventing line pressurization during grounding of the transmission line of the monitoring and control panel recognizing that the transmission line is scheduled to be turned on.
an induced voltage information recording unit for recording line induced voltage information during a power failure of a power transmission line managed by the monitoring and control panel;
a transmission line monitoring unit that checks a power failure state transition of the transmission line from the voltage measured for the transmission line, and recognizes an input schedule of the transmission line;
a ground determination unit that compares the measured voltage of a transmission line in a power failure state with the recorded line induced voltage information during power failure to determine whether or not the power transmission line to be connected is grounded; and
Grounding action unit that allows input to the transmission line when ground release is determined
Line pressurization prevention device during power transmission line grounding comprising a.
According to claim 7,
The ground determination unit,
If the measured voltage of the transmission line falls within a predetermined reference ratio range with respect to the line-induced voltage information, it is determined that the transmission line is grounded,
If the measured voltage of the transmission line does not fall within a predetermined reference ratio range with respect to the line induced voltage information, the line pressurization prevention device during grounding of the transmission line determines that the transmission line is in a grounded state.
According to claim 7,
The transmission line is a three-phase AC power line,
The line induced voltage information recording unit,
If each power failure combination of the three-phase AC power line occurs according to a separate test or power failure work, the power failure for each power failure combination is performed by recording line induced voltage information during power failure of the three-phase AC power line in the corresponding power failure combination. A line pressurization prevention device during transmission line grounding that records line induced voltage information at the time of occurrence.
According to claim 7,
PT for measuring the voltage of the transmission line located at the place where the monitoring and control panel is installed
A line pressurization prevention device during grounding of a power transmission line further comprising a.
According to claim 7,
The transmission line monitoring unit,
Check the voltage fluctuation of the transmission line according to the ground connection of the specific transmission line,
A line pressurization prevention device during grounding of a transmission line that checks a voltage change of the transmission line according to a transition to a power failure state of the transmission line after grounding connection.
According to claim 7,
The transmission line monitoring unit,
Check whether the power failure state is switched by the power failure work set in advance for a specific transmission line,
In the case of a power failure state transition due to the pre-corrected power failure work, a line pressurization prevention device during grounding of the transmission line recognizing that the transmission line is scheduled to be turned on.

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