KR20010064454A - The logical control method of sectionalizer for automated distribution control system - Google Patents

Abstract

PURPOSE: The method for controlling automatic close-trip in fault section on distribution line is provided to shorten time to search fault sections and operate automatic close-trip efficiently checking large sections at once and checking small sections thereafter, during fault, by dividing distribution lines into large sections and small sections. CONSTITUTION: The central control center monitors line faults according to passing fault current using active element like circuit breaker and recloser on normal condition in the first stage. The second is to check a number of the counter of fault information stored in the pertinent switches outputting YES/NO information of fault detection to be able to know whether fault current flows into the respective auto-switches or not. The third is the stage to display the results on the screen, judging the fault occurred in between the switch to respond YES and the switch to respond NO against the above YES/NO information. The fourth is the stage to perform separating operation and switch-on operation of no-fault sections by judgment of operator. The last stage is to perform programs for distribution automation according to the stages in which the circuit breaker requests help from the distribution control room, in which the recloser accepts remote close operation, and to transmit to all no-fault sections except the fault section.

Description

The automatic control of failure section of distribution line {The logical control method of sectionalizer for automated distribution control system}

The present invention provides a conventional method in which an automatic recloser circuit breaker (recloser, hereinafter referred to as "recloser") and an automatic segment circuit breaker (referred to as "Seconnizer", hereinafter referred to as "Secondizer") of a distribution line are mutually eliminated. The present invention relates to a method for automatically opening and closing a failure section of a distribution line which improves efficiency by remotely detecting a failure and controlling it remotely.

In detail, the substation breaker (CB) is responsible for eliminating the fault section in the 22.9 KV distribution system, which is generally adopted as the supply voltage of the distribution line. Reclosers, sexualizers, and line fuses (hereinafter referred to as RSF systems) are often used to reduce power outages caused by failures.

In the conventional RSF system, as shown in FIG. 1, when a failure occurs in a state in which a breaker CB, a recloser REC1, and a protective device of SECN1, SEC2, and SEC3 are disposed, FIG. As shown in Fig. 2, when the first failure is recognized, the recloser (REC1) performs re-closing after about 2 seconds after performing one shutdown, and if the failure does not disappear naturally, it will trip again (about 8 cycles). After 2 ~ 5 seconds, repeat re-insertion, and if the fault does not disappear naturally, the second trip will occur again. In this case, the delay of about 20 cycles is determined by the operation delay curve curve. After the excitation, the third automatic opening is performed, and after that, the fourth is automatically re-inserted after about 15 seconds. If it is impossible not to be re-supplied.

On the other hand, the section analyzer uses the moment when the recloser (REC1) repeats the process of automatic shutoff and automatic reinsertion, and the sectionizer counts the passage of the fault current and the voltage-free number and the recloser of the power supply is opened. At the same time, automatic failures are made to distinguish fault zones.

This series of sequence control is based on the logic control of the electronic control circuit embedded in the recloser and the fractionator. The above is the outline of the operation of the conventional R-S-F system.

However, if the distribution automation control system for remotely controlling the distribution line is introduced, the conditions will be different. Therefore, the existing technology will be actively applied, and the complementary technology will be applied. It is necessary to improve the reliability and operability since it requires clear and logical determination and electrical separation, as well as the reverse transmission action of the sound zone except the failure section in the remote area.

The remote control communication method for this is considered to be wired or wireless. In the related art, a one-to-one communication method has been developed, and a device arranged along a line by a remote terminal unit and a one-to-one communication method installed in many switchgear devices at a time. It is not only a long time to communicate with them, but also it is not reliable and furthermore, the logical judgment method is inefficient.In addition, the control method in the central control station requires the operator to do some or all of the first and second operations. There have been problems such as confusion, defects in the ability to efficiently monitor and control the entire apparatus.

Therefore, there is a need to establish a basic framework of a control program that can control a consistent, logical, and easily controlled whole, as well as to examine the introduction of a suitable switchgear R-S-F system.

On the other hand, the maximum advantage of the recloser is the failure elimination rate by re-input. Statistically, 95% of the failure is eliminated by the first automatic re-injection, and retransmission occurs, which is assumed to be the cause of instantaneous contact and is immediately forced. In the present invention, the unnecessary power outage can be reduced by performing the retransmission of the furnace.

Under conventional conditions, the method of remotely detecting faults and separating fault sections requires a program that depends on the operator or logically solves and expands the fault detection results of hundreds of units at a single workplace, thus increasing the control program of the central unit. However, in the present invention, while operating one distribution line into large and small sections, as soon as a failure occurs, the first and second sections are first searched for failures and then the corresponding sections are searched to determine the failure section quickly and efficiently. The purpose is to provide a detection and switching control method.

Another object of the present invention is to output a failure signal to the section control unit that is already in use, in addition to the remote operation device that monitors the operation from afar, to determine the failure section search result logically at the central control station and then to the center. It is to make it possible to simply use the existing sectionizer by adding a control device that can open and close the operation command from the control station.

In order to achieve the above object, the present invention first performs a large section search using only active elements such as a recloser, and performs a small section search to sequentially check the switch of the fault detection sensor unit. typical Yes / No and to use the logic of the (TRUE / FALSE), and as well as storing the number of times so as to count the number of occurrences of failures detected by adding a counter to a memory circuit, characterized by providing it to the far-field.

1 is a diagram showing the arrangement of the line protection device of the conventional distribution line.

2 is a diagram showing an operation process for fault detection of a conventional recloser.

3 is a diagram showing an ideal arrangement of the line protection device in the conventional wiring line.

Figure 4 is a flow chart showing a process of fault detection in the long run according to the present invention.

Figure 5 is a block diagram schematically showing the configuration of an embodiment according to the present invention.

Figure 6 is a diagram showing the arrangement of the line protection device for detecting the small section failure according to the present invention.

7 is a diagram showing the operation of the recloser according to the present invention.

8 is a diagram showing the arrangement of a fixed section automatic switchgear of a distribution line according to the present invention.

9 is a flowchart illustrating a process of a failure prevention program according to the present invention.

♣ Explanation of symbols for main part of drawing

1: Phase ground current input unit 3: Ground current level unit

4: Current current detection unit 5: Phase current level unit

6: phase current detection unit 7: fault current operation unit

8: counter portion 9: counter reset portion

10: fault current state operation part 11: battery

12 current measuring unit 13 ground current inrush inhibiting unit

14: ground fault current suppression unit 15: phase current inrush control unit

16: Phase current drainage correction 17: Phase, ground and ground in preparation

20: heater 22: voltage, current detection unit

23: field, remote operation selection part 24: opening part

25: input part 26: field / remote operation state part

27 current transformer protection unit

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

FIG. 3 shows a first large section consisting of a breaker CB11 and a seconizer (SEC11) (SEC12), a second large section consisting of a recloser (REC11) and a seconizer (SEC13) (SEC14), and a recloser. In the case of a distribution line consisting of (REC12) and third section (SEC15) and SEC16 (SEC16), if it is tripped by recognizing whether the breaker CB11 is tripped as shown in FIG. If a search is performed and not a trip, it is checked whether the first recloser REC11 of the second cod is tripped. Similarly, if the failure of the cod is detected by performing the process of searching for the second cod and performing the process of searching for the third cod, if it is not a trip, then it is determined to sequentially determine the failure of the small cod within the cod. The method can be used to detect faults efficiently.

Therefore, in order to search the logical section as above, the communication terminal equipment used for the recloser as an active element should use the same performance as the communication terminal equipment for the circuit breaker of the substation. New logic functions need to be added to allow remote control with suppression and delay functions.

First, the internal structure of the section analyzer used in the prior art (FIG. 5) shows a phase and ground current input unit 1 protected by the current transformer protection unit 27 while detecting the magnitude of the current flowing in the distribution line proportionally. A ground fault current detection unit (4) for receiving a fault current transmitted from the phase and ground fault current input unit (1) and determining whether there is a fault current according to the ground fault current determined by the ground fault current level unit (3); A phase current detector 6 for receiving a phase current transmitted from the ground fault current input unit 1 and determining whether there is a fault current according to the phase current determined by the phase current level unit 5, the ground current detector 4 and the phase current detector The fault current operating unit 7 having an operating characteristic that cooperates with the operation characteristics of the recloser and the fuse characteristic curve by the output of (6) and operates with an operating timing proportional to the line current, When receiving the operation signal according to the fault current of the operating unit 7, the counter unit 8 for performing one up count while storing the value thereof, and the counter unit 8 fails while performing the count. The counter reset unit 9 resets the count value to the present time when the cause of the current is removed and the normal operation is performed. If the specified number of times is determined as a result of counting by the counter 8, the output is received. The fault current state operation unit 10 to be operated, the battery 11 which charges and discharges the voltage of the voltage input unit 2, and the current values from the phase and ground current input unit 1 and the battery 11 Ground fault current inrush which suppresses inrush of ground current to prevent inrush current malfunction occurring when the ground current supplied from the current measuring unit 12 and the voltage input unit 2 to be measured is applied in the state of power failure. The ground fault current suppressing section 14 selectively stops the fault current detection function while outputting a latch signal to the ground fault current detection section 4 by the suppression function of the section 13 and the ground current inrush inhibiting section 13. ), A phase current inrush suppression unit 15 for suppressing the inrush of phase current so that the phase current supplied from the voltage input unit 2 performs counting operation or prevents malfunction in the state of power failure, and the phase current suppression unit 15 is suppressed. The phase current multiplier correcting unit 16 which selectively stops the detection function of the fault current while outputting a latch signal to the phase current detection unit 6 by the function, and suppressing the ground fault current while receiving current from the voltage input unit 2. The unit 14 and the phase current drain correcting unit 16 receive the information of the state according to the suppression of the inrush current, and receive the information according to the operation timing from the fault current operation unit 7 above. Phase and ground inrush preparation unit 17 to prepare for the inrush current of the power supply from the AC220V necessary for the internal operation by the power input from the outside supplied to the battery charging unit 19 to supply the battery (11) The power supply unit 18 to charge or supply the heater unit 20 and the voltage value and current value of the power source currently input by the power supply from the voltage input unit 2 and the battery charging unit 19. The portion of the voltage and current detector 22 to be transferred to the counter unit 8 is the same as that of a conventional section analyzer.

The present invention, in addition to the above configuration, the field, the remote operation selection unit 23 for selecting the remote operation, the fault current state operation unit 10 for storing the fault detection result and the number and the external signal received therefrom It is configured to further have a field / remote operation state unit 26 to output to.

In particular, a feature of the present invention is a signal line connected from the fault current state operation unit 10 to the field / far operation state unit 26 and a signal line connected from the field / far operation state unit 26 to the open part 24. Independently, the output of the fault current state operation unit 10 does not directly operate the opening unit 24, but outputs to the central apparatus through the field / far operation state unit 26 capable of remote communication. It is composed of a control circuit that stores the fault detection result and the re-entry frequency (whether the designated number is reached) to inform the fault condition and to receive the opening or closing command from the central control station through the field / far operation state part 26.

Referring to the operation process when the remote operation using the structure having such a structure, as shown in Fig. 6, a plurality of fractionalizer in one recloser (REC21) connected to the breaker (CB21) When a failure occurs at the end of the line in a section connected to (SEC21) (SEC22) and (SEC23), the process of detecting the error occurs in the recloser REC11 when the first failure is recognized in the normal state as shown in FIG. Re-closing after about 2 seconds after a single shut-off and re-transmission, eliminating 95% of instantaneous failures by one re-entry, and reclosing if two re-entry fails. The difference with the existing method is that the section analyzer waits in the closed state without being opened automatically. There is a reverse transmission of.

And this series of operation process can be applied without problems even in the system shown in FIG.

In summary, the above procedure is described in FIG. 9 to monitor line failures according to the passage of fault current in active devices such as breakers and reclosers. Steps,

Investigating the count number of fault information stored in the switchgear by outputting yes / no information of fault detection to know whether fault current flowed to each automatic switch in the central controller;

Determining that a failure has occurred between the switch responding yes to the yes / no information and the switch responding no to the yes / no information, and displaying the result on the screen;

Performing the separation operation of the healthy section and the reverse conveyance operation of the healthy section at the discretion of the Voting Commander;

The breaker requests cooperation from the distribution command center, while the recloser approves the remote input operation so that the entire transmission section except for the failure section is transmitted by the distribution automation program.

According to the automatic opening and closing control method of the fault line of the distribution line of the present invention, the distribution line is divided into several sections from the power supply side to the end point, and an active element, which is an open / close device that independently detects the fault current and blocks the fault current, is arranged. For each subdivision, each subdivision is located in one subdivision, and several subdivisions located within one subdivision can be used to detect faults, but the number of failure detections can be detected by using a detection device attached to an open / close device (passive element) that cannot block itself. The results are logically judged, and when a failure occurs, the large section search is performed first, and then the small section is sequentially searched to efficiently search for the fault section within a short time. Remotely eliminate fault zones and provide logical Which will improve the reliability by ensuring that the waste control device sequentially. In addition, by using the existing control circuit as it is, there is an effect that can reduce the new development burden and expect the enhancement of the function.

Claims (2)

Monitoring the failure of the line according to the passage of the fault current in the central controller first with an active element such as a breaker and a recloser; If a failure occurs on a specific line, the circuit breaker and the recloser perform two re-entry steps, and if the reclosing operation fails, determining the lockout; Outputting yes / no information of the fault detection to each automatic switch in the central control unit to investigate the count of the fault information stored in the switch; Determining that a failure has occurred between the switch responding yes to the yes / no information and the switch responding no; As a result of the operator's judgment, the division of the power section and the reverse transfer operation of the power section are carried out so that the transmission of the entire power section except for the fault section is carried out (distribution automation program). Automatic opening and closing control method. The fault current state operation unit 10 according to claim 1, wherein the distribution line uses a detection method that performs both a large section search and a small section search in a distribution line including a breaker CB and an automatic switchgear. Switch to monitor and judge the fault condition remotely and allow the independent re-entry to operate only on faults other than the fault (95%) that occupy most of the faults, and the fault current state to control them. A method for automatically opening and closing a failure section of a distribution line for transmitting a communication line to a system central unit using a communication line to perform a failure detection program.