JPH0795725A - Device and method for protecting distribution line - Google Patents

Abstract

PURPOSE:To perform quick restart operation after the interruption due to accident by dividing isolating switches arranged on a distribution line in a scattered state into a plurality of groups and providing an accident detecting relay having two kinds of timers to the switches in each group. CONSTITUTION:A power distributing section 3 is divided into a first and second groups L1-L7 and L8-L12 and section switches DMR1-DMR3 for automatically detecting faulty sections are arranged in a scattered state. In the middle of the section 3, circuit breakers CBR1-CBR8 having accident detecting relays Ry are arranged. When a voltage is applied across one side after the switches DMR1-DMR3 are opened, the switches DMRs are closed after, for example, 10 seconds and, thereafter, the switches DMRs are continuously closed for, for example, 1.5 seconds even when the voltage is removed. The opening and closing of the breakers CBRs are controlled similarly to the switches DMRs when the relays Ry do not operate. When the relays Ry start operations, the breakers CBRs are opened, but closed a fixed time after a voltage is applied across one side. When the relays do not restart operations, it is judged that no accident occurs on the load side and, when the relays restart, it is judged that an accident occurs on the load side and the breakers CBRs are again closed. Therefore, a defective section can be specified and sound sections can be quickly restarted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention detects a distribution line accident such as a ground fault or a short-circuit accident and separates a section including the accident point (accident section) to eliminate a distribution line accident. Regarding

[0002]

2. Description of the Related Art In the event of a distribution line accident, after opening all the divisional switches, the divisional switches are re-closed at a preset time interval in order to quickly separate the healthy section from the faulty section. In this way, a system called the "time-progressive power distribution system" is designed to immediately open the circuit breaker at the distribution line outlet when a protective relay installed at the distribution line outlet at the substation detects continuous accidents. It is used.

However, according to this method, when an accident occurs in the distribution line, the circuit breaker at the distribution line outlet of the substation is released, so that the distribution line temporarily loses power. As a countermeasure against this, Japanese Patent Application No. 262222 provides an accident detection relay on the switches distributed in the distribution line so that the settling time of the coordination timer becomes shorter as the distance from the power source increases.

[0004]

However, in this method, the time until the breaker at the outlet of the distribution line is released is limited, and the number of series of switches with an accident detection relay provided from that time is at most. It is 2-3. Therefore, at the time of an accident on the distribution line, it takes a recovery time in the power supply side section that is wider than the accident section.

An object of the present invention is to minimize a power failure section which is a healthy section for detecting and disconnecting a fault section of a distribution line, and to shorten a time required for progressive power supply and shorten a power failure time. is there.

[0006]

In order to achieve the above object, a distribution line protection relay device of the present invention detects an accident provided on a break switch for a distribution line divided into a plurality of groups by a break switch group. Two types of cooperative timers are provided to output an opening command to the breaking switch after the settling time after the relay operates.

The first cooperative timer is provided with a time difference so that the settling time is shortened for each group moving away from the power source end. The same settling time is set in each group.

The second coordinating timer outputs the release command only during the Y time period (time until the switch is closed in the next section) after the accident is shut off and the circuit breakers are closed again.

[0009]

First, when an accident occurs, a coordination time difference is provided so that the settling time of the first coordination timer becomes shorter for each circuit breaker group as it goes away from the power source end.
Any or some of the circuit breaker switches closest to the accident point are activated immediately, and the section including the faulty section is separated. Does not work because. Therefore, the power failure of the healthy section group on the power supply side is avoided.

Further, in the same group, since only the breaking switches in which the protection relay has operated compete for opening, the power breakers in the power supply side that do not operate due to the characteristic difference of the protection relays prevent power failure in the healthy section on the power supply side. It Further, the load side disconnecting switch which does not operate due to the difference in the characteristics of the protection relay is opened after a fixed time period (about 1.5 seconds) after the applied voltage disappears.

Next, of the opened breaking switches, the breaking switch for one-sided charging is reclosed, and the breaking switches including the accident section are sequentially advanced in a timed manner.

Since each of the shutoff switches operates quickly for the second cooperation timer only during the Y period (time until the switch is closed in the next section) immediately after being turned on, if there is an accident in the section, disconnect it immediately. Therefore, the power failure in the healthy section on the power supply side can be done at most once.

[0013]

EXAMPLES The present invention will be described below based on examples.

FIG. 1 shows an example in which the present invention is applied to a 6.6 KV distribution line, in which electric power is supplied from a transformer 1 of a substation to a distribution line 3 through a 6.6 KV power bus 2. Distribution line 3
An outlet breaker FCB is installed at the substation outlet.

Distributor switch control devices DMR1 to DMR1 for automatic detection of a fault section are appropriately distributed and arranged on the distribution line 3, and a break switch control device CB having an accident detection relay Ry in the middle thereof.
R1 to CBR8 are arranged, and the power distribution sections L1 to L12 are divided by these control devices.

The outlet circuit breaker FCB is provided with an accident detection transformer FCT and an accident detection relay FRY. The fault detection transformer FCT is a current transformer, a zero-phase current transformer,
And a zero-phase voltage transformer and a voltage transformer provided on the bus.

Further, the break switch control devices CBR1 to CBR8
As shown in FIG. 2, the breaking switch CB, the accident detection transformer CT, the accident detection relay Ry, and the switch control unit CONT.
1 and also a power supply transformer T ₁ or T ₂ , respectively. The fault detecting transformer CT is provided with a current transformer, a zero-phase current transformer, or a voltage transformer, a zero-phase voltage transformer, or the like, if necessary.

Further, the section switch controller DMR1 to DMR3 for the automatic detection of the faulty section are shown in FIG.
Switch controller CONT2, power transformer T ₁ ′ or T ₂ ′
Are provided respectively.

The switch DM is controlled by the switch control unit CONT2, and after X time (for example, 10 seconds) has passed after voltage application to one side, the switch DM is closed. (For example, about 1.5 seconds) is configured to continue the closed circuit.

When the accident detection relay Ry does not operate, the switch controller CONT1 of the break switch controller CBR controls the opening and closing of the break switch CB depending on the presence or absence of a voltage, like the switch controller CONT2 of the DMR. . In addition, when the accident detection relay Ry operates, a fixed time period (TIM
After ER1), the breaking switch CB is opened, and if there is a voltage on one side, it is closed again after a fixed time. Further, if there is no voltage on both sides immediately after opening, the breaking switch CB is closed after the X time period has elapsed after applying the voltage on one side, as in DMR.

If the accident detection relay Ry does not operate within the Y time period (for example, 8 seconds) which is slightly shorter than the X time period after closing the circuit breaker switch CB, it means that there is no accident on the load side of the circuit breaker switch CB. I reckon. On the contrary, when the accident detection relay Ry operates again during the Y period, it is determined that there is an accident on the load side, and the breaking switch CB is opened after the fixed period (timer 2).

FIG. 4 shows a portion related to the configuration of the switch controller CONT1 of the break switch controller CBR. AND
Of the AND gates 1 to AND3, AND1 and AND3 have an inverter at one input. TIMER1 ~
TIMER3 is a timer for timed operation, each timed t ₀₁
Have t ₀₃ . SEQ is a logic unit that executes a sequence according to an external signal condition.

Now, when the break switch CB is "ON", when a signal is input from Ry, the timer TIM is passed through AND1.
ER1 is activated and, after a time t ₀₁ , issues a release command to the breaking switch CB to release the breaking switch CB. The signal is input to SEQ through the auxiliary contact. Then, when the SEQ recognizes that there is a voltage on one side through the power transformer T ₁ , it issues a closing command to the breaking switch CB after a time period (X time period). When the breaking switch CB is turned on, a CB "ON" state signal is output from the auxiliary contact to the timers TIMER3 and AND3.

Since TIMER3 does not output a signal during the time period t _03, a signal is output from AND3 having an inverter and AND2 is in a state of waiting for a signal from Ry.
That is, after the breaking switch CB is closed, the AND2 gate is opened only for the time period t ₀₃ , and if Ry operates during this period, a release command is issued to the breaking switch CB after the time period t _{02 of the} timer TIMER2. That is, the condition for issuing an opening command for the breaking switch CB immediately after the breaking switch CB is turned on is that the breaking switch CB is
Ry needs to work within t ₀₃ after _{turning on} , and the opening command of the break switch CB is actually output at t ₀₂ after inputting the Ry signal. The opening command of the breaking switch CB after t ₀₃ after the closing switch CB is turned on is issued at t ₀₁ after the input of the Ry signal. Therefore, there is a relation of t ₀₂ <t ₀₁ .

The operation of each part of the embodiment configured as described above will be described with reference to the timing chart of FIG. 5 by taking the case where an accident occurs at point F of the power distribution section L11 as an example. Distribution section L in the figure
In 1 to L12, the shaded area indicates the power-on state, and the blank area indicates the power failure.

Assuming that an accident occurs at point F at time t1, the accident detection relay FRY and the break switch controller CBR.
Since almost the same fault current flows through the fault detection relays Ry of 1 to CBR7, the protection operation is started at the same time. However, by setting the time limit so that the accident detection relay Ry of the disconnecting switch of the second group of L7 to L12 operates faster than the accident detection relay FRY of the outlet, t ₂
At this time, the accident detection relays Ry of the breaking switch control devices CBR5 to CBR7 operate, and the breaking switch control devices CBR5 to CBR5
An opening command is output to CBR7 at the same time, and the opening response time t
_{With a} delay of _{01, the} break switch control devices CBR5 to 7 are activated at time t.
Opened at ₃ .

At this time t _3, the outlet breaker FCB and the first group of interrupting switch control devices CBR1 to CBR4 in the distribution sections L1 to L7 are not yet opened, and the outlet accident detection relay FRY and the first switch. The accident detection relays Ry of the breaker switch control devices CBR1 to CBR4 of the first group judge that the accident has been eliminated, and the outlet break break switch FCB and the breaker switch control devices CBR1 to CBR4 of the first group are finally disconnected. Absent.

Therefore, the outlet circuit breaker FCB and the first group of circuit breaker switch control devices CBR1 to CBR4 are not opened, so that the power distribution sections L1 to L7 do not fail. On the other hand, the distribution sections L8 to L1 including the distribution section L11 having the accident point F
2 has no voltage. As described above, one feature of the present invention is that the power distribution sections L1 to L7 that do not include an accident section do not experience a power failure.

Immediately after any or all of the breaker switch control devices CBR5 to CBR8 are opened by the operation of the accident detection relay Ry, the breaker switch control device CBR5 (or CBR6 or CBR7) of which one side is in the voltage applied state is X time limit. When (for example, 10 seconds) has elapsed, the closing operation is performed by the control device CON.
Perform from T1. Consequently distribution leg L8 (CBR5 when poured) is voltage application (time t _5).

Next, the circuit breaker control device CBR6 is closed (time t ₆ ) when X time (for example, 10 seconds) elapses after one-sided pressurization. As a result, the distribution section L9 is charged, and the switch D
MR3 is to become a one-side division voltage state, further closed after X timed (time t _7). Thus, the distribution leg L10 are voltage application, and then blocking switch controller CBR7 is X timed after closing (time t _8), and the distribution section L11 are voltage application.
This is called the progressive power supply method.

If the accident in the power distribution section L11 is eliminated, the operation starts as it is, but if it is not eliminated, the accident occurs again as shown in FIG.
The FRY and the break switch control devices CBR1 to CBR7 both start operating the accident detection relays Ry. However, in this case, unlike the operation of each accident detection relay timer at the time of the first accident, the CBR7 accident detection relay Ry + timer operates faster than other accident detection relays + timers, so the breaker switch control device CBR7 opening command is given to only (time t _9), after response time of the shut-off switch CBR7 (t _01), blocking switch CBR7 is opened (time point t _10).

As described above, according to the present invention, the power distribution section L8
-L10 does not have a power outage due to a re-occurrence accident, and requires only a short power outage only during the time-forwarding. Break switch CBR7 here
After closing the circuit, no voltage was applied within the Y time limit to prevent the occurrence of an accident, and the subsequent progressive function is locked according to the rules of the progressive power feeding system.

Although the embodiment of the present invention has been described with reference to the system of FIG. 1, as is apparent from the above description, the scattered switch D.
The breaker switch control device CBR is arbitrarily inserted in M, and the settling time of the first cooperation timer in each group is separated from the power supply end by dividing it into two or more groups of two or more in series from the power supply end. Coordinated time differences that shorten each group are provided, and the break switches in the same group are set to the same settling time. Once the accident has been interrupted, the break switches will be used only during the Y period during reclosing of the break switches. It is to shorten the settling time of the release command timer (second cooperation timer) to the breaking switch.

FIG. 6 shows an application example in which a breaker switch control device CBR is installed at a branch point of one feeder. Two breaker switch control devices CBR are provided from the outlet breaker FCB to the non-power source end. Groups are connected in series, and the same operation as in the case of FIG. 1 is expected in any section accident.
In this case, it is of course possible to arbitrarily include the section switch controller DMR for automatic detection of a failure section between the break switch controllers CBR. In addition, even if two or more groups of breaker switch control devices CBR are installed in series, they can be connected to other switch DMs.
It is obvious that it is good to arbitrarily switch (so that there are two in series) as long as the same operation as can be performed. In particular, the distribution line has extension wiring or the like for accommodating load and the like, so this has a great effect.

In the embodiment of the present invention, the circuit breaker switch control device CBR may not be a circuit breaker that cuts off a short circuit current, but may be a switch that targets only a ground fault.

[0036]

Industrial Applicability The present invention relates to a progressive power supply and charging system that has been widely used in the past. The existing switch DM equipment using the progressive power supply and charging system is used as it is, and an accident detection facility (accident detection relay Control device CON for Ry + break switch
It is intended to minimize the power failure time and its range by providing the breaking switch controller CBR having T). Therefore, the contents regarding the control system of the break switch controller CBR may be taken into consideration at the time of new installation. For example, it can be implemented by newly inserting the break switch controller CBR while leaving the existing switches DMR1 to DMR3 of FIG. .

In the conventional system using the switch DM, the number of the switch DM is limited because the number of the switch DM increases because the repeated control is required for a long time before the accident section is separated. As described above, the invention divides the switch DM group into several groups and installs the break switch controller CBR at these group connection points. Therefore, as a whole, the control for the accident section determination is performed by the conventional method. It will be significantly shortened.

[Brief description of drawings]

FIG. 1 is a distribution line system diagram showing an embodiment of the present invention.

FIG. 2 is a configuration diagram of circuit breaker switch control devices CBR1 to CBR8.

[Fig. 3] Sectional switch controller DMR for automatic detection of faulty section
It is a block diagram of 1-DMR3.

FIG. 4 is a configuration diagram of a switch controller CONT1.

FIG. 5 is an operation timing chart of each part constituting the present invention.

FIG. 6 is an application example in which a break switch controller CBR is installed at a branch point of one feeder.

[Explanation of symbols]

CBR ... Shut-off switch controller, DMR ... Faulty section automatic detection switch controller, FCB ... Outlet breaker, FR
Y ... Accident detection relay, 1 ... Transformer, 2 ... Power bus, L
1 to L12 ... power distribution section.

Claims (3)

[Claims] 1. A distribution line is divided into a plurality of groups by arranging switches in a distributed manner, and each switch of each group is provided with an accident detection relay having two kinds of cooperative timers, and said break switch is provided. Distribution line protection device characterized by limiting acceptance of the opening command of 2. The first coordinating timer according to claim 1, wherein the first cooperative timer is settled so as to output an open command faster as the respective groups move away from the power source end, and the second cooperative timer has each of the breaker switches set to 1 A distribution line protection device that sets a permissible time for a release command that is input after the circuit is closed and reclosed. 3. The distribution line is divided into a plurality of groups by arranging the switches in a distributed manner, and the breaking switches are opened after the switches are opened by an accident detection relay provided in the switches for each group. A method for protecting a distribution line, characterized in that, when the circuit is reclosed, an opening command time to the breaking switch is shortened when the accident detection relay operates within a specific time after the reclosing.