JPH1032924A - Device for sectionalizing faulty section of power distribution system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the function of a power distribution system by restoring a sound section on the upstream side of a faulty section, by disconnecting the faulty section during a power failure due to a ground fault through communication between switchgears. SOLUTION: The point of difference of the constitution of a device for sectionalizing faulty section of power distribution system from the conventional constitution is that switchgears VS1-VS5, each of which comprises a sectioning switch 5 and a switch controller 9, are provided and, at the same time, a three-phase current transformer 10 which detects a system current is provided near the load side of the switchgears VS1-VS5. The controller 9 is provided with a backup power source 11, a control processing section 12, a radio transmitter-receiver 13, and a storing section 14. When, for example, a ground fault is caused in a section #3, the detected results of the ground fault direction of the switchgears VS3 and 4 are inverted and the section #3 is discriminated as a faulty section from the inversion. The switch controller 9 of the switchgear VS3, the load-side section #3 of which becomes the faulty section, locks the sectioning switch 5 of the switchgear VS3 to an opened state, based on the discrimination.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a faulty section of a distribution system for locking a section where a ground fault has occurred in a distribution line from an upstream healthy section by locking a section switch in an open state.

[0002]

2. Description of the Related Art Conventionally, in a distribution system, as shown in FIG. 8, a three-phase distribution line 4 is connected to a system power supply 2 of a substation 1 through a circuit breaker 3, and this distribution line 4 switchgear VS _1, VS _2, ... a plurality of sections by section switches 5 #
0, # 1, # 2,...

[0003] Further, each switchgear VS _1, VS _2, ... is formed by switch control device 6 for opening and closing the switch 5 of the section switch 5 Toko, the switch controller 6 transformers 7,
The operation is performed by using either the system power supply on the upstream side (the power supply side or the substation side) or the load side of each of the segmented switches 5 via the switch 8.

[0004] Conventionally, a timed failure section detection function is added to each switch control device 6, and if a ground fault occurs in any section, the breaker 3 will be re-closed as described below.
The fault section in which the ground fault has occurred is disconnected from the system by the trial charging of the distribution line 4 by the re-injection.

Namely, switchgear VS ₁ order of five from the upstream side to the distribution line 4 as shown in FIG. 9, ..., VS ₅ is provided, the load-side self-section # 3 of the switchgear VS ₃ at time ta Assuming that a ground fault has occurred in FIG. 10, as shown in FIG.
Trips and changes from closed (ON) to open (OFF).

[0006] When the system voltage of the distribution line 4 is lost by opening the circuit breaker 3, sectionalizing switch 5 of the switchgear VS ₁ ~VS ₅ is opened.

Next, when one minute elapses from the occurrence of the ground fault and reaches tb, the circuit breaker 3 is reclosed, and the reopening causes the section #.
0 When resuming, closed sectionalizing switch 5 of the most upstream switchgear VS ₁ is turned in a predetermined charged timed Tauon.

[0008] own interval # 1 of the switchgear to tc VS ₁ This turned the power recovery, switching device VS ₁ is predetermined detection time period τd from the input of the section switch 5 by the switch control unit 6 (<τon) It is monitored whether or not the system voltage of the section # 1 disappears within the period.

Since the section # 1 is sound and the system voltage of the section # 1 does not disappear even after the detection time τd elapses, the next section # 1 after the power-on time τon elapses from the power recovery of the section # 1.
The switchgear 5 of the _second switchgear VS2 is turned on and closed.

[0010] By this input, the own section # of the switchgear VS ₂
2 When resuming the td, monitors whether the system voltage of the section # 2 in the detection time period τd is lost by switch control unit 6 of the switchgear VS _2.

Since the section # 2 is sound and the system voltage of the section # 2 does not disappear even after the detection time τd elapses, the next section # 3 after the power-on time τon elapses from the power recovery of the section # 2.
Sectionalizing switches 5 switchgear VS ₃ is turned in, the sectionalizing switch 5 is closed to te.

At this time, section # 3 is a faulty section in which a ground fault has occurred, an overcurrent flows again in the distribution line 4, the circuit breaker 3 is again tripped and opened, and the distribution line 4 is cut off.

[0013] This power failure is detected from the power recovery in the section # 3 until the detection time period τ.
d, the switch control device 6 of the switch VS ₃
Locks the sectional switch 5 of the own section # 3 in the open state.

When three minutes have elapsed and the time tf has elapsed, the circuit breaker 3 is closed again, and thereafter, the time t is delayed by the closing time τon.
The switching devices VS ₁ and VS ₂ of the sections # 1 and # 2 are time-sequentially switched on at times g and th, and the healthy sections # 0, # 1 and # 2 upstream of the failure section # 3 are sequentially restored. To charge.

Further, even if power is restored a healthy section # 2 in th is section switch 5 of the switchgear VS ₃ Breakdown section # 3 is locked in the open state, the sectionalizing switch 5 is not turned on, the fault section # 3 and each section # 4, # 5 on the load side are disconnected from the system. Therefore, the fault section # 3 is separated by the test charging of the circuit breaker 3 for re-closing and re-closing, and the sound sections # 0 to # 2 on the upstream side are restored.

[0016] Further, the malfunction section # 3 than the load side of the sound interval # 4, power recovery # 5, the Fukuden work based on the detection of a fault section # 3, sectionalizing switch of the switchgear VS ₄ sections # 4 5
Is locked in an open state, a normally open linking switch (not shown) at the load end of the distribution line 4 is closed, and the distribution line 4 is disconnected from the load side by another distribution system via this switch. It is done by charging.

[0017]

When a ground fault occurs as in the prior art, when the circuit breaker 3 of the substation 1 is closed,
When the distribution line 4 is time-sequentially trial-recharged by a reclose circuit and the faulty section # 3 is separated from the system, the upstream healthy sections # 0 to # 0
It is necessary to perform the test charging twice in a time-sequential manner before # 2 recovers power, and there is a problem that it is not possible to quickly recover power in the healthy sections # 0 to # 2. In addition, there is also a problem that the power distribution line 4 stops again after the power is restored by the trial charging of the reclosing circuit, and a plurality of power failures of the distribution line 4 occur.

According to the present invention, in the event of a ground fault, the faulty section can be separated quickly and the faulty section can be separated without repeating the trial charging of the distribution line, preventing the repetition of the power outage, and restoring the power in the healthy section. The task is to

[0019]

In order to solve the above-mentioned problems, a faulty section of a distribution system according to the present invention is provided with a backup power supply for supplying operating power to each switchgear during a power failure of a distribution line. And a means for detecting the direction of the ground fault, and communicating with the adjacent switchgear, and in the event of a ground fault accident, adding the detection result of the ground fault direction to the received information as accident information to the received information by communication of information gathering, and connecting between each switchgear. Means for sequentially transmitting and distributing the accident information of each switchgear as a collection result to each switchgear in reverse to the information collection communication by the information distribution communication after the information collection communication, and Means for detecting a faulty section from the accident information of each switchgear, and, based on the detection result of the faulty section, when the load-side own section is a faulty section, the section switch of the own apparatus is opened before the distribution line is restored. Means for locking.

Therefore, when a ground fault occurs in a distribution line, the detection result of the ground fault direction of each switching device is sequentially transmitted and collected between the switching devices by communication of information collection between the switching devices. Further, by communication of information distribution between the respective switching devices after the information is collected, the collected detection results of the ground fault directions of all the switching devices are distributed to the respective switching devices and held.

Each switchgear detects a faulty section from the distributed detection result of the ground fault direction of each switchgear. If the own section is a faulty section, the faulty section is classified during the power failure due to the ground fault accident. Lock the switch in the open position.

[0022] Therefore, the communication between the switchgears disconnects the faulty section from the system during the power failure due to the ground fault, so that the distribution line can be quickly and without the need to repeat the charging of the distribution line, and the distribution can be performed in the event of a power recovery. Power is restored in the upstream healthy section without repeating power outages.

[0023]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to FIGS. 2 shows the power distribution system, conventional configuration differs from the FIG. 8, a conventional switchgear VS _1, VS _2, ... instead of, comprising a section switch 5 switch controller 9 Metropolitan switchgear VS1 , VS2, ...
And a three-phase current transformer 10 for detecting a system current near the load side of each of the switching devices VS1, VS2,.

The switch control device 9 is configured as shown in FIG. 1, and includes a backup power supply 11 charged by a system power supply via the transformers 7 and 8, a control processing unit 12 of a microcomputer configuration, and an adjacent switch. Devices VS1, VS
The control processing unit 12 is provided with a storage unit 14 such as a non-volatile memory for storing information and the like.

As shown in FIG. 1, the current transformer 10 includes current transformers 10a, 10b, and 10c for each phase, and outputs detected currents of the current transformers 10a to 10c to the control processing unit 12. Is done.

Next, the control processing section 12 will be described. The control processing unit 12 executes a preset program for failure detection, opening / closing control, and communication control, and includes the following units.

Ground fault direction detecting means The detected current of each phase of the current transformers 10a to 10c is monitored, and when a ground fault occurs, the direction of occurrence of the ground fault is determined for each phase from the magnitude of the detected current of each phase. This is means for discriminating and detecting whether it is on the upstream side or the load side of the own section # 1, # 2,..., And the detection result is stored in the storage unit 14 as accident information.

Communication control means for collecting and distributing information Adjacent switchgears VS1, VS via radio transceiver 13
It is means for exchanging information with the switch control device 9 of 2,..., For example, by wireless polling communication, and performing communication of the next information collection and information distribution.

(I) Information collection communication Continuously (periodically) or every time an accident occurs, the storage unit 14 stores the received information from the upstream switchgear VS1, VS2,. The transmission information is formed by adding the latest accident information of the sections # 2, # 3,..., And this information is transmitted to the switchgear VS2, VS3 next to the load side set on the transmission side.
, And transmits and collects accident information of the switching devices VS1, VS2,... Sequentially between the switching devices VS1, VS2,.

(Ii) Communication of information distribution Each time the communication of information collection is completed, the collected accident information of all switchgears VS1, VS2,. VS2,... VS2, VS2,.
2, are stored in the storage unit 14. The number of switchgears VS1, VS2,... Of one distribution system is generally about seven. Even if the communication of one information collection and information distribution is sequential polling communication, The operation is completed within a time shorter than the time (1 minute) from the time of opening due to a ground fault to the time of re-closing.

(Iii) Fault section detection means Each switchgear VS1, VS2,.
From the accident information described above, a section at the boundary where the ground fault direction is reversed is detected as a failure section.

(Iv) Fault section separating means When the fault section detected by the fault section detecting means is the load-side own section # 1, # 2,... Is a means for disconnecting from the system.

Next, the switching devices VS1, VS2,.
A case where a ground fault occurs in section # 3 as shown in FIG. 3 will be described. First, when a ground fault in section # 3 occurs at Ta, as shown in FIG. 4, the circuit breaker 3 of the substation 1 immediately trips and opens, and the power distribution line 4 experiences a power failure. Each switching device V based on the disappearance
The segmented switches 5 of S1 to VS5 are opened.

At this time, each of the switching devices VS1 to VS5 is operated by the backup power supply 11, and the respective current transformers 1
The ground fault direction is detected for each phase from the detected currents 0a to 10c,
The accident information of the detection result is written and stored in the storage unit 14.

Further, during the power failure, wireless communication for information collection and information distribution is performed, and as shown by the broken line a in FIG. 5, the respective switching devices VS1 to VS5 are operated in a predetermined order by the wireless communication for information collection. The accident information is sequentially transmitted between the switch control devices 9, and the accident information of all the switch devices VS1 to VS5 is collected.

Further, by wireless communication for information distribution, FIG.
The accident information collected in the reverse of the information collection is distributed to the switch control devices 9 of the switchgears VS1 to VS5 and held in the respective storage units 14 as shown by the broken line A in FIG.

As shown in FIG. 6A, for example, a communication signal for information collection and information distribution includes a first transmission type area a and a last end code (end code) area b.
The area c ₁ to c ₅ accident information of each switchgear VS1~VS5 is formed is provided between the.

Further, the transmission type area a is shown in FIG.
As shown in the figure, the synchronization area a ₁ , the information collection / distribution identification area a ₂ , the communication start address (polling start address) area a ₃ , the call address area a ₄ indicating the next transmission destination, and the communication consisting of area a ₅ of the end address (polling end address).

Then, a so-called synchronization signal is written in the synchronization area a ₁ , identification information indicating whether to perform information collection or information distribution is written in the identification area a _2, and an area a _{3 of} each address is written. the ~a _5, the address of the switchgear VS1 to start collecting information, address switchgear next to the sender that varies according to a transmission, the last address of the switchgear VS5 collect information is written. In the area b, an end code (end code) END is written.

[0040] Then, when the failure information of each switchgear VS1~VS5 and DVS1～DVS5, when communicating information gathering in order to area a ₄ addresses the address of the switchgear VS5 from the address of the switchgear VS2 according to a transmission with rewritten, the area c _1, c _2, the successively each ... accident information VDS1, VDS2, ... are written.

For this reason, a communication signal transmitted from, for example, the first switchgear VS1 to the adjacent switchgear VS2 by the information collection communication is as shown in FIG. 6C.

In the last switchgear VS5,
The received communication signal includes the accident information DVS1 to DVS4, and all the switching devices VS1 to VS1 are determined by the information DVS1 to DVS4 and the accident information DVS5 of the own device VS5.
Accident information DVS1 to DVS5 of VS5 is collected.

Further, as shown in FIG. 6D, communication signals for information distribution are provided in each of the switching devices V in the areas c _{1 to} c _5.
Accident information DVS1~DVS5 of S1~VS5 consists written signal, the address of the area a ₄ is changed in order to address the switchgear VS1 from the address of the switchgear VS4 by transmission.

Next, the switch control device 9 of each of the switching devices VS1 to VS5, based on, for example, the distribution information shown in FIG.
The ground fault direction in S5 is identified.

When a ground fault occurs in section # 3, the detection results of the direction of ground fault of switchgears VS3 and VS4 are reversed, so that section # 3 is determined to be a failure section by this reversal. Based on this determination, the switch control device 9 of the switchgear VS3 in which the load-side own section # 3 has become a failure section,
Immediately lock the sectional switch 5 in the open state.

The disconnection of the failure section # 3 based on the lock in the open state is performed within one minute from the occurrence of the ground fault accident until the circuit breaker 3 is closed again. Then, when one minute elapses from the occurrence of the ground fault and reaches Tb, test transmission is performed in a time-sequential manner. Therefore, as shown in FIG. 4, the circuit breaker 3 of the substation 1 is reclosed in a conventional manner.

When power is restored in section # 0 due to this reclosing,
The switchgear VS1 is set at Tc after the passage of the closing time τon from Tb.
Are closed and closed, and section # 1 is restored. Further, when the switching time τon elapses from Tc and reaches Td, the sectional switch 5 of the switching device VS2 is closed and closed, and power is restored in the section # 2.

At this time, the sectional switch 5 of the switch VS3
Is locked in an open state, the section switch 5 of the switchgear VS3 is not turned on even if the turning-on time τon elapses after the restoration of power in the section # 2, and as shown in FIG. And healthy sections # 0 to # 2 upstream thereof are restored. The arrow in FIG. 7 indicates the direction in which the ground fault is detected.

The disconnection of the faulty section # 3 is performed during the power failure due to the ground fault, and the breakage of the breaker 3 causes the healthy section # 3 to be disconnected.
Since the power is restored in 0 to # 2, the power restoration in the healthy sections # 0 to # 2 is performed more quickly than in the conventional case where the power is restored by the re-closed circuit. In addition, there is no power failure in the healthy sections # 0 to # 2 due to the trial charging after the occurrence of the accident.

It is to be noted that a period between the failure section # 3 and the healthy side on the load side #
For # 4 and # 5, the power is restored from other linked systems by the same power recovery operation as before, and power is recovered.

In order to detect and isolate a faulty section by communication between the switchgears VS1, VS2,..., A master station device for remote monitoring control is provided, for example, at a business office of a power company. Information is exchanged with the switch control device of the switchgear to detect a faulty section, which eliminates the need for expensive master station equipment, etc. as compared with the case where this section is separated by master station control. It is a target.

The number of switchgears VS1, VS2,... And the method of detecting the ground fault direction may be of any type. For example, the detection of the ground fault direction may be performed for all phases at once. Further, the signal transmission direction of the information collection and the information distribution may be opposite to the above, and the signal transmission may be performed by wire. Further, the communication signal format and the like may be any.

[0053]

The present invention has the following effects. When a ground fault occurs in the distribution line 4, each switchgear VS
Through the communication of information collection and information distribution between 1 to VS5, the detection results of the ground fault directions of all switchgears VS1 to VS5 are collected and distributed to the respective switchgears VS1 to VS5, and distributed by the switchgears VS1 to VS5. Switchgear VS1 to VS
The faulty section is detected from the detection result of the ground fault direction of 5, and if the own section is a faulty section, the section switch 5 of the own section is locked in an open state during a power failure due to a ground fault accident.

Therefore, the communication between the switchgears VS1 to VS5 makes it possible to disconnect the faulty section during the power failure due to the ground fault and to quickly and distribute the test without repetitively charging the distribution line 4. Without repeating power outages of the electric wire 4, power can be restored in the upstream healthy section, and the function of the power distribution system can be significantly improved.

[Brief description of the drawings]

FIG. 1 is a block connection diagram of a switchgear according to an embodiment of the present invention.

FIG. 2 is a system diagram of a power distribution system provided with the switchgear of FIG. 1;

FIG. 3 is a system diagram when a ground fault occurs in the distribution system of FIG. 2;

4 is a timing chart for explaining the operation of each unit of the system in FIG. 2 when power is restored from a ground fault.

FIG. 5 is an explanatory diagram of communication of information collection and information distribution between the switching devices of FIG. 1;

6 (a) to 6 (e) are explanatory diagrams of the communication signal and the information to be transmitted in FIG. 5;

FIG. 7 is a system diagram for explaining power restoration of the power distribution system of FIG. 2;

FIG. 8 is a system diagram of a conventional example.

FIG. 9 is a system diagram when a ground fault occurs in the distribution system of FIG. 8;

FIG. 10 is a timing chart for explaining the operation of each unit of the system in FIG. 8 when power is restored from a ground fault.

[Explanation of symbols]

 Reference Signs List 4 distribution line 5 division switch 9 switch control device 10, 10a to 10c current transformer 11 backup power supply 12 control processing unit 13 wireless transceiver VS1 to VS5 switch

Claims (1)

[Claims] A distribution line is divided by a plurality of switchgears of a plurality of switchgears, and a switchgear control device of each of the switchgears controls opening and closing of each of the switchgears so that a fault section in which a ground fault accident occurs is provided. In the faulty section classification device of the distribution system that locks the immediately preceding section switch in an open state, a backup power supply that supplies an operation power to the switchgear during a power outage of the distribution line, and a unit that detects a ground fault direction. Communicates with the adjacent switchgear, and when the ground fault occurs, adds the detection result of the ground fault direction to the received information by communication of information collection as accident information and sequentially transmits between the switchgears; Means for sequentially transmitting and distributing the accident information of each switchgear of the collection result to the respective switchgear in reverse of the information collection communication by the information distribution communication after the information collection communication; Things about each switchgear Means for detecting the faulty section from the information; and, based on the detection result of the faulty section, when the load-side own section is the faulty section, the section switch of the own device is locked in an open state before the distribution line is restored. And a means for dividing the distribution system into faulty sections.