KR0124040B1 - Distribution line on/off system & line switch control apparatus - Google Patents

Abstract

A switching method of the distribution line and a control means of the line switch whereby the status of the line switch is enabled to control remotely, the end user grip the managing situation quickly and the record is restored depending on the communication and managing situation.

Description

Distribution line open and close method and line switch control device

1 is a block diagram showing the shape of a general radial distribution line,

2 is a block diagram showing the shape of a general dendritic distribution line,

3 is a block diagram showing a general loop distribution line shape,

4 is a block diagram showing the shape of a general composite distribution line,

5 is a block diagram showing the configuration of a control apparatus for an automatic line control switch according to the present invention;

Figure 6 is a flow chart showing the overall operation of the automatic switch control line according to the invention,

7 is a flowchart showing an operation process of a real-time control interrupt of the automatic line control switch according to the present invention.

8 is a flow chart showing the operation of the communication interrupt of the automatic line switchgear of the present invention.

9 and 10 are flowcharts and diagrams showing an operation assumption in which the automatic track switchgear of the present invention is selected for a section.

11 and 12 are flowcharts and diagrams showing an operation process of a state in which the automatic track switch of the present invention is selected for coupling.

* Explanation of symbols for the main parts of the drawings

1: Current transformer 3: Current detector

5, 7: transformer 10: voltage detector

11: microprocessor 12: memory

13: display unit 14: communication module

15: input and output 16: open drive

17 input drive 20 switch

21: contact part.

The present invention relates to a three-phase Y multiple ground distribution line opening and closing automation, and more particularly, to a distribution line opening and closing method and a line switch control device to accurately control the opening and closing state of the line switch while efficiently operating the distribution line opening and closing automation.

In general, the distribution line cooperates with a circuit breaker (CB) and a line switchgear that is a substation breaker, and a recloser (Rec) for eliminating transient and permanent failures, and the recloser (Rec) and circuit breaker ( As a line section switch (SW) for separating fault sections in cooperation with a back protection device such as a CB), an automatic section switch (Sec) or a reclosing sectionalzer capable of re-entering for almost the same purpose; It is well known that RS is combined and operated.

In addition, the combined operation is performed by using a tie switch (TS), which is operated in the open state at the position combined with the line configured at other substations and banks for the loop line operation and can be fed back. Sometimes.

With the diversification of line operations, the entire system for control of distribution lines has become more complex and the quality of service for customers has to be improved. Therefore, the necessity of distribution lines has been further emphasized. The operating system will be described in detail as follows.

1 to 4 illustrate the basic form of each distribution line operation method. First, the radial system shown in FIG. 1 is the simplest form of operation. Conventionally, an automatic section switch (Sec) is used as a section switch SW for cooperating with the recloser Rec, which is a hobby protection device, to isolate the failure section Fa by fault current detection and counter cooperative operation. The maximum number of installations that can cooperate with Rec is limited to three or less, and there were limitations on the series expansion of the distribution lines and the segmentation of sections.

Fault detection as voltage detection and timing coordination using the switchgear section switch (RS) as section switch (SW) to (SW14) cooperating with the circuit breaker (CB) or recloser (Rec11), which is a post-protection device in another conventional manner. There is a method of separating the section Fa, but this is because the recloser Rec11, which is a back protection device, in order to remove excessive faults in the grounding system is cooperated with the operation that is delayed and opened when the sequential operation is performed. It is difficult to set the operating time of the opening and closing section switch (RS) according to the operation of the operation and the unreasonable point due to the correction of the time occurred.

In addition, when the reclosing section switch RS inputs the fault section Fa during the check-in process, when the recloser Rec11 cuts the fault current again and becomes voltageless, the section switch switches SW11 and SW12 of the other healthy section also become voltageless. Since the opening is completed after the completion of the timing in each order in order to open all, there is a problem that the recovery time of the power line increases as well as the number of installations increases, and the number of operations of each switch increases.

Figure 2 shows a block diagram of a branched distribution system, which includes the application of a radial line operation as a branching line coupled to a single radial form.

Therefore, when permanent failure occurs in the failure section (Fb) after the branch line, conventionally, the recloser (Rec21) is input in the confirmation input process, and the breaker switch (SW23) is input after the switch (SW21, SW22) for the section is input. When the other switchgear side switch (SW25) at the same time is also input at the same time, as soon as the recloser (Rec21) cuts off the fault current, when the power failure occurs, the switchgear (SW23) is immediately opened to open the section switch ( SW25) is also locked out, as well as all the switches (SW21, SW22) will also be opened again.

In addition, in order not to lock out the section switch SW25, the timing of the switchgear SW23 and SW25 should be prioritized in order to give priority to the timing of closing the switchgear SW23 and SW25.

Therefore, the more branch points are required, the more complicated correction procedure is required, the uncomfortable process is expected when the line section is increased or decreased, and the complete return time of the healthy line is required.

3 is a block diagram showing the operation of the loop system (loop system), which includes the operation of a single radiation line operation as a method for reverse transmission for the automatic recovery of the health zone.

In the conventional loop line, since the fault section (Fe or Fd) is input during the reverse transfer, there is a contradiction to repeat the operation for eliminating the fault section such as the first through the B-power side health line, so the application is practically applied in the more detailed section. it's difficult.

However, the conventional method used in the non-grounding system has the advantage of allowing reverse feeding after opening the section switch (SW32, SW33) at both ends of the fault section (Fe), and immediately failing the coupling switch (TS34). In the event of a failure of the section Fd, the section switch SW33 is open-locked out, and voltage-free detection and timing control may be possible in a manner that the section switch SW34, which is normally open, is not immediately put in front of the coupling switch TS34. As a whole, the number of operations of each switch SW31, SW32, SW33, SW35, SW36, SW37 increases, and the return time is long.

Therefore, the object of the present invention is to cooperate for the transient failure irrespective of the reclosing time of the recloser, reducing the number of operations of the switchgear when removing the fault section, it is possible to shorten the time to complete the line return, The present invention provides a distribution line open / close method and a switch control device that allow an operator to grasp the operation state of a switchgear in a system more quickly by providing a remote control or state.

Another object of the present invention includes the operation method of the radial line, by only opening the switch-out of the breakdown section of the faulty branch line failure to open the lockout isolating the fault interval, the input timing does not need to set the time difference differently, and unnecessary power regeneration of other wires This prevents the return and shortens the return time.

Still another object of the present invention includes a radial line operation method, but it is possible to determine whether the fault line is inserted in the case of the reverse feed of the loop line to prevent unnecessary input of the failure section, and to restart the blackout of the other key wire combined I did not do it.

Another object of the present invention includes all the operation methods and control functions listed in the radial, dendritic, and loop phase applications, respectively, and the automatic control section switchgear has a function of preventing input when both power supplies are present at the same time in the open state. It is to be included.

It is still another object of the present invention to communicate information by operating a switch (current, voltage, phase and state of the switch) by using a single-packed microprocessor in accordance with a cooperative relationship with a recloser (REC) or a circuit breaker. It is to keep record of function and main operation status.

In order to achieve the above object, the present invention provides a step of achieving cooperation for eliminating transient failure by counting operation regardless of the instantaneous reclosing time of the dobby protection device, and the health section switchgear is reopened in the process of confirming and removing the permanent failure. Do not perform unnecessary operation to be re-injected, and open only the switchgear of the fault section to lock out to separate the permanent fault section, and the switchgear of the already-used health section is not reopened. When the fault section of the branch line is removed, the sound section switch of the other branch line is opened again and does not perform unnecessary operation. The switch of the heavy dividing line is not opened again, and the dog If there is a failure of the section directly connected to the combined switchgear, do not automatically input the back-feed, and if it is a failure of the other line section, it automatically separates only the fault section and returns it to the sound line by back-feeding. It is performed by the steps of automatically suppressing the input when both sides of the power supply are present so that it is possible to determine whether the fault line is inserted during the reverse feed of the loop line and to prevent unnecessary input of the fault section with the advantage of the radial line application. Even if the section is further subdivided by maintaining an auxiliary coordination sequence for eliminating the power failure of other cables and maintaining the ground fault system, it is possible to quickly and reliably carry out the mission of the loop line system, as well as radial, resinous, When applied to a loop line, the control power is automatically suppressed along with the control capability. Therefore, it is possible to apply to any dendritic loop line is configured to combine.

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

FIG. 5 schematically shows the configuration of the automatic control section switch (SFAS) control device, in which current flowing through the line is flowed through the current transformer 1 at an appropriate ratio to be input to the three-phase and ground current input unit 2. In addition, the current signals rectified by the three-phase and ground fault current input unit 2 are converted into voltages of appropriate levels so that they are input to the current detection unit 3 as control signals proportional to each other. The control power supply 9 directly connected to the transformer 5 for detecting the voltage flowing therethrough supplies the voltage to the microprocessor 11 to be used as a control voltage, and detects the voltage flowing through the load-side line 6 through the voltage. The voltage from the transformer 7 and the transformer 5 is transformed and rectified by the three-phase positive voltage input unit 8, and then supplied to the voltage detector 10 so as to provide a signal according to voltage detection. The microprocessor 11 includes a CPU, a timer, an interrupt controller, a decoder, and an A / D converter to generate a signal according to a phase detection, and the detection result of the current detector 3 and the voltage detector 10 may be generated. To control the overall operation according to information such as current, voltage, and phase state, and the microprocessor 11 stores information and data necessary for the memory 12. The ROM 12a controls the operation. Program and fixed data, and the EEPROM 12b stores state information of the control device and check information during operation, and the SRAM 12c temporarily stores information generated during an operation. The display unit 13 of the liquid crystal display (LCD) under the control of the processor 11 may selectively display three-phase current information, voltage, ground current, and optional input information. The communication module 14 receiving the digital serial information from the microprocessor 11 converts it into modem information and transmits it to a remote controller not shown in the drawing, or converts the modem information input therefrom into digital serial information and converts it into a microprocessor ( 11) the remote communication is enabled while the input / output unit 15 receiving the open signal or the input signal from the microprocessor 11 is output to the open driver 16 or the input driver 17 and tripped. A contact for opening or closing the switch 20 while selectively driving the coil (TC) 18 and the input coil (CC) 19, and detecting a state according to the opening or closing of the switch 20. In the unit 21, the detection result is transmitted to the microprocessor 11 through the input / output unit 15.

Here, the user inputs an option for changing the set value or confirming the state through the key input unit 22.

Although the current transformer 1, the power supply side line 4, the load side line 6, and the switch 20 are shown one by one, they are installed in three places or four places according to three-phase three-wire or three-phase four-wire.

The line breaker control apparatus of the distribution line of the present invention configured as described above can compare the line currents from the current detector 3 and the voltage detector 10, the power line voltage, the load line voltage, and the phase comparison results of the power supply voltage and the load voltage. The microprocessor 11 converts the digital information into the digital information through the A / D converter, and then takes appropriate measures while determining the state of the line breaker based on the program stored in the ROM 12a of the memory 12. Power is supplied to the control device as shown in FIG. 6 (step 100), and the microprocessor 11 determines whether the line breaker as shown in FIG. 5 is set as a section switch or a combination switch. It is installed and operated to separate the section, or it is installed and operated to allow the reverse conveyance in the always open state for the loop line. In step 101, the switch is operated in the set state for the section or the coupling (step 102) while setting the state of the control device.

In this case, when the switch is used as a section switch, the microprocessor performs functions such as prevention of malfunction due to transient failure and inrush current, shaft tripping function, fault detection function, and temporary recovery of the battery section. In the case of being used as a switchgear, the automatic back feed function, the input suppression function in the case of phase mismatch, etc. are performed by the microprocessor, which can be set by a remote method via the communication module 14 or a local key by the key input unit.

Then, the information according to the contact state (open, closing and gas pressure state) of the switch 21 detected through the contact portion 21 is read by the microprocessor 11 via the input / output unit 16 and initialized (step) 103, initialize the internal system (step 104).

Next, the microprocessor 11 performs a real time control interrupt that checks a predetermined period while checking whether a predetermined time has elapsed through the internal timer (step 105). When the period of time is reached, the three-phase current and the ground current are input through the current detector 3 and the line voltages of the power line 4 and the load line 6 are read through the voltage detector 10 (step 106). ).

Next, it is checked whether or not a communication interrupt state is received by the microprocessor 11 via the communication module 14 with the optional specification by the remote controller (step 107). Checking whether the input is made by the local mode for inputting the option (step 108), and outputting a control signal to the display unit 13 only when there is an optional input through the key input unit 22 so as to input the information inputted through this. At the same time, the control signal is outputted to the input / output unit 15 according to the input information to perform the operation of opening and closing the switch 20 while operating the open driver 16 or the input driver 17 (step 109). The process of calculating a phase through the voltage information input through the voltage detector 10 is repeated (step 110).

7 illustrates a process of performing a real-time control interrupt mode. When the user sets an interrupt time (a predetermined time of a predetermined period) while adjusting an internal timer (step 111), the microprocessor 11 recognizes this. The time data and the flag are controlled (step 112), and the current information and the voltage information are sent to the current detector 3 and the low charge detector 10 each time the time elapses while the operation of the switchgear is controlled. After performing the operation of the LCD display control to maintain the display data of the display unit 13 for a predetermined period with the state of the control operation stored in the memory 12 after being read through (step 113), the timer is controlled and The time interrupt is terminated (step 114).

8 illustrates a process of controlling input / output of data to perform remote control by a communication interrupt, and confirms whether the transmission interrupt state for outputting information to the outside through the communication module 14 ( In step 120), if the transmission interrupt state is set, the microprocessor 11 sets the transmission control flag (step 121) so that the data is normally output to the remote controller through the communication module 14 by the transmission control flag. On the other hand (step 122), if it is not the transmission interrupt status in step 120 or when data transmission is normally performed, the microprocessor 11 checks whether the reception interrupt status is received from the remote controller (step 123). If receiving interrupt status, read optional input data received through communication module 14 Shall be performed by a process of storing in the memory 12 is set (step 124), the receiving control flags, which are then (step 125).

9 and 12 show a state of controlling the operating state of the system. When the state of the system is used for the section, the flow of FIG. 11 is used by the control flow chart of FIG. It works by chart.

Then, the information of the system which is periodically read from the system is changed in the state (voltage state → no voltage, no voltage state → voltage, steady current state → fault current state → normal current and the time when the state changed and the set time) By controlling them in combination, the switchgear is controlled by judging the failure of the front end or the rear end of the corresponding line breaker.

If the user sets the section for the section by the remote or local mode (step 130), the microprocessor 11 that recognizes the state sets the internal state for the section (step 131), and sets the voltage detector 10. Check if there is no voltage state (step 132).

If no voltage is detected by the voltage detecting unit 10, the input unit 22 or the communication module 14 checks whether there is a signal input of an opening request by the user (step 133), If not, return to the initial operation of the step while maintaining the current state (step 134), and if there is a signal input of the open request, the open signal to the input / output unit 15, the control signal to the open drive unit ( 16, the switch 20 is opened by the trip coil 18 so as to be in an open to lockout state (step 135).

If no voltage is checked in step 132 above, it is again checked whether there is a signal input of an open request (step 136). If there is no input of an open request, the controller returns to step 135 if there is no input of the open request. The input voltage is again sensed (step 137).

If no voltage is detected, it is determined as a primary no-voltage state (step 138), while if a voltage is detected, a return timer is set to monitor the voltage state (step 139) to confirm whether there is a signal input of an open request by the user. (Step 140).

If there is a signal input of the opening request by the user, the microprocessor 11 recognizes this, and returns to the initial operation. If there is no input of the opening request, it is checked whether the return timer has expired (step 141). It is judged that the fault has been eliminated and returns to the initial operation to maintain the steady state for the section.

If the timer is not expired, the microprocessor 11 that recognizes the second voltage is detected until the timer is terminated (step 142). Since the fault has not yet been eliminated, an open control signal is output to the input / output unit 15 so that the open driver 16 opens the switch 20 by the trip coil 18 to the sequencer at its front. Try to refill (step 144).

The microprocessor 11 checks whether the voltage is sensed in the temporary open state in which the switch 20 is opened by the open signal in step 135 (step 145), and when the voltage is sensed through the voltage detector 10, In order to check whether there is a fault, the input timer is set as the input time data to enter the input check state for the interval to start the clock (step 146).

The microprocessor 11 checks whether or not the input timer has elapsed in the input check state for the section (step 147). If the voltage is still detected while the input timer is terminated (step 148), it is regarded that there is no failure ahead. After the input signal is outputted to the input driving unit 18 through the input / output unit 15, the switch 20 is input by the input coil 19 (step 149), and then the rear timer is set to grasp the failure in the rear. To be in the checked state of the post-failure for the section to be revealed (step 150).

When switching on the switch, make sure that there is a load side power supply to prevent collision of both power sources.

If the input timer is not terminated in step 147, the microprocessor 11 checks whether no voltage is detected until the timer expires (step 151), and if no voltage is detected, determines that a failure has occurred in the front. Set the potential timer to check this (step 152), and check whether the potential timer for checking the failure in front is neighboring (step 153), and if the timer is adjacent, it is regarded as a failure immediately before the switch 20 ) Is in the state of Lock Out At Open which is locked out (step 154).

Then, the microprocessor 11 checks whether the voltage is detected before the timer neighbors through the voltage detector 10 (step 155), and if detected, enters the interval checking state and returns to step 146.

In step 150, the microprocessor 11 checks whether the pick timer is neighboring (step 156) while checking that there is no front failure and checking the rear failure. The controller returns to the initial operation while switching to the normal state for the section, and checks whether no voltage is detected while the timer is operating (step 157), and if the fault current is detected again (step 158). ).

When a fault current is detected in the microprocessor 11 while the timer is operating, the lockout for opening the switchgear 20 by the trip coil 18 while operating the open driver 16 through the input / output unit 15 is provided. It is made to be in an open to lock out state (step 159).

On the other hand, in the case where the switch 20 of step 154 is locked out in the open state or is out by opening the switch 20 of step 159, it is checked whether the input signal is input by the user (step 160). ), When the input signal is inputted, it returns to the normal operation by switching to the normal state for the section.

The operation process according to the flowchart shown in FIG. 9 is illustrated in the diagram so that it can be seen at a glance as shown in FIG. 10.

11 is a view illustrating an operation process in a state in which the line breaker of the present invention is set for coupling, and an input signal is input from the user through the key input unit 22 or the communication module 14 in the normal state in which the switch 20 is open. If the input signal is inputted, check whether the input signal is input (step 161), and check the phase while acquiring the phase information obtained by the operation through the line voltage information in the microprocessor 11 that recognizes the input signal (step 162), The closing coil 19 is operated through the closing driver 17 so as to be switched to a state of closing to lock out to allow the switch 20 to be closed (step 163).

If there is no input signal in step 161, the microprocessor 11 checks whether no voltage is detected (step 164). If no voltage is detected, the phase is not in phase when the input signal is input. Return to initial operation while maintaining the normal state for coupling, such as disregarding the input signal.

On the other hand, if no voltage is detected in step 164, the microprocessor 22 checks whether the voltage is detected through the voltage detector 10 (step 165). While returning to 164, when the voltage is sensed, the recovery timer is operated to time the switch to switch to the coupling return confirmation state for recognizing whether the voltage continues to be detected for a predetermined time period (step 166).

The microprocessor 11 checks whether the return timer is completed (step 167), and if it is completed, returns to the normal state for coupling and returns to the initial operation, and if it is not completed, checks whether no voltage is detected ( Step 168) /

If no voltage is detected, the microprocessor 11 recognizes that the input timer is operated to be in the check state for the coupling (step 169), and checks whether the timer is over in the check state of the coupling input (step 170). When the timer of the input is completed, the microprocessor 11 recognizes the input signal through the input / output unit 15 to the input driver 17 so that the switch 20 is input by the input coil 19. After that, it is set to a state of loss to lock out (step 171).

If the timer is not completed, the microprocessor 11 checks whether the voltage is detected through the voltage detector 10 (step 172), and if it is detected, determines that a failure has occurred in the front and sets the potential timer (step 173), the operation of the input timer is stopped so as to be switched to the state of the combined forward failure check for confirming the failure in the front (step 174).

Check whether the potential timer is out (step 175), and if it is out, the microprocessor 11 returns to the initial operation while deeming a normal state for coupling, and if it is not out, checks whether no voltage is detected. (Step 176) If it is detected, it is determined that a failure has occurred in the front, the switchgear 20 is to be in the state of the lock out (Lock Out At Open) to lock out without the input.

In this state, it is checked whether the user inputs the reset signal through the key input unit 22 (step 177), so that the control flag data of the control device is cleared only when it is input, and then switched to the normal state for coupling. (Step 178).

In operation 163 and 171, the microprocessor 11 checks whether the open signal is input by the user in the locked out state (step 179). Open and allow to return to steady state (step 180).

The operation process according to the flowchart shown in FIG. 11 is illustrated in the diagram so that it can be seen at a glance as shown in FIG. 12.

When the switch of the present invention as described above is applied to the composite track method, as shown in FIG. 4, the fault section Fe is generated, and the section switch SW41 is input after the recloser REC41 is input in the confirmation input process. Finally, the section switch SW42 is finally opened and opened, and the switches SW43 and SW45 are locked out in the open state in the same manner as the operation of the loop-type track system.

Therefore, when the coupling line automatic control switches TS44 and TS47 are inputted in the reverse direction after the input timing, and when the section switch SW46 is input, only the failure section Fe is bent and the rest of the healthy sections can be returned to normal operation.

In addition, when the failure section Ff is generated and the section switch SW41 is open-locked out as described above, and the coupler switches TS44 and TS47 are simultaneously introduced in the reverse feed, the section switch SW43 and SW46 are next. Is input at the same time, followed by the sequence switch SW45, but since there is already power on both sides of the section switch SW45, at this time, the section switch SW45 is not opened due to the input blocking function. Will be maintained.

Of course, when one of the power supply is out of power, it is turned on after the timing of the input, and the normal control function is possible.

And, in the case of the fault section (Fg) also operates as described above, the section switchgear SW43 is open-locked out, and the combined switchgear TS44 is locked out in the open state so that the fault section Fg is not injected. Section switchgear SW41 and SW42 are input by re-insertion of the recloser REC41, section switchgear SW45 and SW46 are input in turn, and voltage is returned from the A-power supply side again during input timing on the coupling switch TS47 side. Since both power sources (A, B-power source) are applied at the same time, the closing timing is reset to normally open state.

As stated above, the distribution line opening and closing method and the circuit breaker control device of the present invention can cooperate with the rear closure (Rec) or the circuit breaker (CB), which is a post-protection device, to subdivide the section to the maximum in any type of line operation method. In addition, it is easy to use because it is easy to correct and does not repeat unnecessary power outages and operations of the health line, thereby contributing to service improvement by economical and quicker return to the line.

And, only the coordination ability and fault section for eliminating the transient failure and the return of the power line can be automatically solved by the switchgear itself, which is a disadvantage of the power switchgear control, which is emerging as a disadvantage of the power line carrier method for distribution automation. It is possible to provide a method for solving the problem of algorithm processing and the problem of disconnection of communication means.

In particular, the user can correctly determine the operating state of the system by remotely controlling or providing the state of the switch, and it is a feature that enables the record keeping according to the state of communication and operation using a microprocessor.

Claims (6)

A microprocessor 11 for controlling the overall operation by receiving the detection results of the current detector 3 and the voltage detector 10 connected to the current transformer 1, the power supply side transformer 5, and the load side transformer 7; 12a), an EEPROM 12b, and an SRAM 12c, a memory 12 for storing information and data of the microprocessor 11, and an LCD for controlling current and voltage ground under the control of the microprocessor 11; A display unit 13 for displaying information and information selected and input by the user, and a communication module for converting modem information input in the remote mode of the user into digital serial information, or converting information from the microprocessor 11 into modem information. 14 and the open driver 16 or the input driver 17 in response to the open signal or the input signal from the microprocessor 11 or receive the state of the switch 20 through the contact part 21. Micro pro Stand 11 automatically switch the control device to the distribution line, characterized by consisting of a the input and output section 15 to the charge. When power is applied to the control unit, checking whether it is set for section or coupling, initializing the system after reading the contact state of the switch while operating in the set state, and real-time control for checking a certain period. Computing the phase difference from the current, line voltage, line voltage of the three-phase and ground fault while performing an interrupt, and notifying the display unit 14 while receiving the option according to the remote or local mode, and the input information Distribution line opening and closing method, characterized in that carried out by the step of controlling the switch 20 according to. The method of claim 2, wherein the real-time control interrupt mode comprises the steps of setting a constant cycle interrupt time, By checking time data and flags according to the set interrupt time and checking whether or not it is a fixed time of a certain period, and reading current information and voltage information at a predetermined time and displaying them on the display unit 13 for a predetermined time. Distribution line opening and closing method characterized in that performed. The method according to claim 2, wherein the communication interrupt mode confirms whether the communication interrupt mode is present, if it is a transmission interrupt, sets a transmission control flag to thereby output data, and ends transmission or interruption. Or checking whether the reception interrupt is received, and if the reception interrupt is received, reading the data input through the communication module and setting the reception control flag. A method for opening and closing a distribution line with a line breaker set for a section; Checking whether there is an input of an opening request in the normal state, and if there is no opening request, returning to the normal state if there is no opening request, and opening the switch if it is in a lockout state for opening; Opening the switch when there is an input of open request in the no-voltage state, and detecting the voltage to make the first no-voltage state if there is no input, and setting the return timer when the voltage is detected in the no-voltage state to open during timekeeping. Checking whether a request is input, returning to the normal state where the failure is eliminated if there is no opening request to terminate the return timer, and detecting whether no voltage is sensed until the return timer expires. Step to be a temporary open state to open the switchgear 20, and when the voltage is detected in the temporary open state Setting an immer to be in the closing check state for the section to check whether there is a failure in the front, and putting a switch 20 when the voltage is sensed while the closing timer is finished in the closing check state for the section; Setting to set the state of the post-failure check, and, if no voltage is detected before the closing timer expires, setting the potential timer to open the lockout in which the failure occurred immediately before Returning to the normal state when the pick timer is out of the checked state, and checking whether a fault current is detected when no voltage is sensed while the pick timer is in operation to be in an open state for the lockout; Normal state for the section when the user's input request is input in the open state of the lockout or the open state for the lockout Distribution line opening and closing method characterized in that performed by the steps of returning to. A method for opening and closing a distribution line with a line breaker set for coupling; When the input request is input from the user in the normal state for coupling, checking the phase and switching to the state of input for lockout; if there is no input signal and if there is no voltage, returning the normal state for coupling; If no voltage is detected in the absence of state, it is determined as the primary no-voltage state and if voltage is detected, switching to the return confirmation state for coupling while operating the reset timer, and if no voltage is detected during the completion of the reset timer, Switching to the normal state and operating a closing timer when no voltage is detected, and switching to the state of the closing check for coupling, and in the state of the closing check for coupling, if the voltage is not detected until the closing timer is completed, the switchgear 20 Switching to a state of input for the lockout for engagement, and if a voltage is detected during operation of the input timer, Switching to a state of engagement forward failure for stopping the input timer while operating the timer; switching to an open state of the lockout if no voltage is detected while the potential timer is out; If the open signal is input in the open state for opening the switch 20 to switch to the normal state for engagement, and if the reset signal is input in the open state of the lockout, the control flag data is cleared after the normal connection Distribution line opening and closing method characterized in that performed by the step of switching to the state.