JPH01243814A - Protective-device for circuit reclosure - Google Patents

Abstract

PURPOSE:To prevent an accident from being increased, by setting the re-closing command of output generated for a fixed time after a breaker is re-closed, or re-closed circuit monitoring signal and the working output of a distance relay, as the condition of the trip of the breaker, and by releasing a time limiting circuit in accordance with the distance relay when said condition is satisfied, to generate the output of breaker trip command. CONSTITUTION:From a re-closing circuit RC, even after a breaker CB is re- made, for a fixed time, re-closed circuit monitoring command is continuously generated, and the input of the re-closed circuit monitoring command to respective AND circuits AND1-AND3 is provided. Even if the transmission is started by the making of the breaker CB, in case that a short circuit accident is still not recovered, the distance relay DZ2 of a second step is worked again, and the input of its output to the AND circuit AND2 is provided, and its output is applied to a breaker trip circuit TP, and the breaker CB is released.

Description

[Detailed Description of the Invention] [Purpose of the Invention (Field of Industrial Application) The present invention provides a method for protecting feeder lines adopting an AC electrification system in stages using multiple stages of distance relays with different protection ranges. This invention relates to a re-route protection device for Shiki electric wires.

(Prior art) In feeder lines that adopt the AC electrification system, as shown in Fig. 3, the bus lines Bl,
82 and between the bus lines B2 and 83 between this auxiliary sorting station SSP and sorting station SP, feeder lines Ll, L2 and L3. L4 connects two lines, an up line and a down line, respectively, and circuit breakers 1 to 4 are installed on the substation SS side and the auxiliary dividing station SSP side of both lines, and a breaker is installed on the auxiliary dividing station SSP side. 5.6, a circuit breaker 7 is installed between the connections of both lines on the side of the substation SP.Then, the protection range is changed in the direction of the auxiliary section SSP for both lines on the bus Bl side of the substation SS. A plurality of stages, here three stages, of distance relays 8 to 10.
11 to 13 are connected to each other via current transformers CT. Distance relays 14 and 15 for protecting the substation SS direction are also connected to both lines on the auxiliary division station SSP side via current transformers CT. In addition, auxiliary division station SS
Feeder line L3 connected to P side bus bar B2. L4 also has a two-stage distance relay 16 with different protection ranges in the direction of the separation station SP.
．． 17 and 18.19 are connected through current transformers CT, respectively.

Here, the first stage distance relay 8゜11 on the substation SS side has a protection range of 80% from the substation SS to the auxiliary division station SSP, and the second stage distance relay 9, 12 has a protection range from the substation SS to the auxiliary division station SSP. The protection range is 64% between the substation SS and the substation SP, and the third stage distance relay 10.13 has a protection range spanning both lines from the substation SS through the substation SP to the auxiliary substation SSP. There is. In addition, the distance relay 14.15 on the auxiliary dividing station SSP side has a protection range from the auxiliary dividing station SSP to the substation SS, and the first stage distance relay 16.1
8 has a protection range of 80% from the auxiliary sorting station SSP to the sorting station SP, and the second stage distance relay 17.19 is connected from the auxiliary sorting station SSP to the auxiliary sorting station SS
The protection range spans both lines up to P.

By the way, in order to provide short-circuit protection for the feeder line in such a system, the distance relays DZI, DZ2, . The output of DZ3 is passed through time limit circuits TI and T2゜T3 with different operating times to the circuit breaker tripping circuit T.
P is energized. In this case, the distance relays DZI, DZ2 . The protection cooperation time period of the DZ3 is set so that the first stage is short, and the second stage and the third stage are sequentially longer, that is, the first stage, the second stage, and the third stage.

Therefore, the distance relays DZI, DZ2 . In order to protect the feeding system shown in Fig. 3 using the DZ3, for example, if a short circuit occurs at point F shown in the figure, first the breaker 2 is opened by the operation of the distance relay 14 on the auxiliary division station SSP side, and then the power substation is restarted. After the second stage distance relay 9 on the SS side is activated and the setting time limit of the time limit circuit T2 has elapsed, the circuit breaker 1 is opened.

After a certain period of time has elapsed, the circuit breaker 1 is turned on by a restart command from a re-closing circuit (not shown) on the substation side, and if the short-circuit accident F continues at that time, the time-limiting circuit T2 is turned on again.
The circuit breaker 1 is opened after the settling time period has elapsed.

(Problems to be Solved by the Invention) However, as shown in FIG. 4, three stages of distance relays DZI, DZ2. In the case where the feeder line is protected by DZ3, the output of the distance relay at each stage is connected to the time limit circuit Tl,
T2. T3 is given to set the protection coordination time, but since this protection coordination time is maintained even after the breaker is reclosed, if a short circuit occurs at a remote point on the wire, There is a problem in that it takes a long time for the circuit breaker to open after it is reclosed, leading to an increase in accidents.

SUMMARY OF THE INVENTION An object of the present invention is to provide a recirculation protection device that can promptly open a breaker even if a distance relay operates again within a certain period of time after the breaker has been recirculated, thereby preventing the spread of accidents involving electric wires. do.

[Structure of the Invention] (Means for Solving the Problems) In order to achieve the above-mentioned object, the present invention provides a plurality of stages of distance relays with different protection ranges for protecting feeder lines employing an AC electrification method, and a distance relay for each of these stages. and a time limit circuit provided corresponding to each of the distance relays, each having a different operating time to achieve protection coordination, and when the distance relay is operated by re-closing a circuit breaker provided in the feeder line, its output is set to the time limit. In a recirculation protection device configured to disconnect the breaker through a circuit, a reclosing command or a reclosing monitoring signal issued for a certain period of time after reclosing the breaker and an operational output of a distance relay are used as breaker tripping conditions, The configuration is such that when this condition is satisfied, a means is provided for releasing the time limit circuit corresponding to the corresponding distance relay and outputting a breaker tripping command.

(Function) In the re-circuit protection device having such a configuration, if the distance relay of any stage operates within a certain period of time after the breaker is re-circuited, the time limit circuit corresponding to the distance m relay of that stage is released. Since the breaker trip command is issued after the breaker is restarted, if the accident continues when the breaker is reopened, the breaker can be opened immediately, which prevents the spread of the feeder line accident. can.

(Example) An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block circuit showing an example of the configuration of a recircuit protection device according to the present invention. In FIG. 1, DZI, DZ2.
For example, DZ3 is a three-stage distance relay that protects the upstream feeder line L1 on the substation SS side of the main system shown in Figure 3.
Distance relays DZI, DZ2 . DZ3 is connected to feeder line L1 via a current transformer CT. In this case, the first stage distance relay DZ1 is connected to the substation S as in Fig. 3.
The protection range is 80% of the auxiliary separation station SSP from the S side, and the protection range of the second stage distance relay DZ2 is 64% between the auxiliary separation station SSP and the separation station SP from the substation SS side. Step distance i! i! The relay DZ3 is set as a protection range from the substation SS side to the auxiliary dividing station SSP via the auxiliary dividing station SSP and the dividing station SP through the downlink. Also, TI, T2. T3 is a time limit circuit provided corresponding to each stage of the first to third stage distance relays DZI to DZ3, and each of these time limit circuits TI.

T2. T3 is for setting a protection cooperation time limit for the operation of the distance relays DZ1 to DZ3, and the operation time limit is set to Tl<72<73.

TP is a circuit breaker in which time limit circuits T1 to T3 are energized by the operation of distance relays DZI to DZ3, and when the set time limit has elapsed, the operating output of time limit circuits T1 to T3 opens the circuit breaker CB provided in feeder line L1. It is a trip circuit. Also, ANDl.

AND2. AND3 is distance relay DZI, DZ2゜DZ
These AND circuits ANDI, AND2. A
When the AND condition is satisfied, ND3 turns on the time limit circuits T1 to T.
3 is released and the breaker tripping circuit TP is activated by its output.
It operates.

Next, the operation of the recirculation protection device having such a configuration will be described.

In the main system shown in Fig. 3, for example, a short-circuit accident occurs at point F in the figure, the second stage distance relay DZ2 on the substation SS side operates, and the breaker CB is activated after the setting time of the time-limited circuit T2 has elapsed. The operation until it is released is the same as that described above (description of the conventional example).

When a certain period of time has elapsed since the breaker CB was opened, a re-closing command is issued from the re-closing circuit RC on the substation SS side, and the breaker CB is closed by a breaker closing circuit not shown in Figure 1. .

In this case, the restart circuit RC continues to receive a restart monitoring command for a certain period of time even after the circuit breaker CB is turned on.
This re-route monitoring command is input to AND circuits AND1 to AND3, respectively. Even if power transmission through the feeder line L1 is started by turning on the circuit breaker CB, if the short-circuit accident F is still occurring at that time, the second stage distance relay DZ2 operates again, and its output is input to the AND circuit AND2. do. Therefore, this AND circuit AND2 satisfies the AND condition by inputting the restart monitoring command, the distance m of the second stage, and the operation output of the electric appliance DZ2, so its output is applied to the breaker tripping circuit TP, and the breaker CB is It will be released.

In this case, the operating output of the second stage distance relay DZ2 is applied to the time limit circuit T2, and this time limit circuit T2 is connected to the AND circuit A.
When the AND condition of ND2 is satisfied, the state is released, but there is no problem since there is no need to coordinate protection when opening the circuit breaker.

Figure 2 shows a comparison of the time from turning on the breaker to shutting off the circuit again using the conventional method and this device when a short circuit occurs in the main system shown in Figure 3, for example at point F. It shows a chart. That is, as shown in FIG. 2, when an accident occurs and the distance relay DZ2 operates, the breaker CB is opened when the protection cooperation time limit of the time limit circuit T2 has elapsed. Then, after a certain period of time has elapsed since the breaker CB was opened, the breaker CB is closed by a restart signal output from the restart circuit. The operation up to this point is the same for both the conventional method and this device, but if the fault continues when the circuit breaker CB is turned on, in the conventional method, the second stage distance relay DZ2 is activated as shown by the solid line. After the protection cooperation time limit of time limit circuit T2 has elapsed, circuit breaker CB is activated.
will be released. On the other hand, in this device, when the second stage distance relay DZ2 operates as shown by the dashed line, the breaker is tripped due to the AND condition between its output signal and this special reclose monitoring signal. Since a command is issued to the breaker trip circuit TP, the breaker CB is opened almost simultaneously with the operation of the second stage distance relay DZ2. Therefore, it can be seen that the present device can shorten the cutoff time Ts compared to the conventional system. Due to this,
Since the breaker CB can be opened quickly even when the accident point is far away, there is no longer a situation where the accident is amplified due to a delay in the breaker's disconnection time as in the conventional case.

In addition, in the above embodiment, in the feeding power system shown in FIG.
We have described the case where an accident occurs within the protection range where the second stage distance relay DZ2 operates, but if the accident occurs within the protection range where the first stage distance relay DZ1 operates or the third stage distance relay D
Even in the case where an accident occurs within the protection range in which only Z3 operates and the accident continues even after the circuit breaker CB is re-closed, the same re-route protection as described above can be performed. Further, in the above embodiment, the recirculation monitoring command signal after the reclosing command is issued from the reclosing circuit RC is used as the breaker tripping command condition, but the recirculating command issued from the reclosing circuit RC is used as the breaker tripping command condition. This re-closing command itself may be used as long as it continues for a certain period of time even if it is re-closed.

[Effects of the Invention] As described above, according to the present invention, even if the distance relay operates again within a certain period of time after the circuit breaker is reopened, the circuit breaker is promptly opened to prevent the spread of an accident on the feeder line. It is possible to provide a recirculation protection device that can

[Brief explanation of the drawing]

Fig. 1 is a block circuit diagram showing an embodiment of the reclosing protection device according to the present invention, Fig. 2 is a time chart showing the response state of the same embodiment in comparison with a conventional system, and Fig. 3 is an AC electrification system. A system diagram in which the adopted feeder wire is protected by a distance relay, and FIG. 4 is a block diagram of a protection circuit using a conventional distance relay. DZ1~DZ3... Distance relay, T1~T3・
...Time limit circuit, TP...Breaker tripping circuit, AND 1 to AND3...AND circuit, RC...Reclosing circuit. Applicant's agent Patent attorney Takehiko Suzue Figure 1 Figure 2

Claims (1)

[Claims] It is equipped with multiple stages of distance relays with different protection ranges that protect feeder lines that adopt the AC electrification system, and time-limited circuits that are provided corresponding to each stage of distance relays and provide protection coordination with different operation times. , in the reclosing protection device, in which when the distance relay operates due to reclosing of a breaker provided on the feeder line, the output thereof is passed through the time limit circuit to open the breaker; The timed reclosing command or reclosing monitoring signal and the operating output of the distance relay are used as the breaker tripping conditions, and when this condition is met, the time circuit corresponding to the applicable distance relay is released and the breaker tripping command is output. A reclosing protection device characterized by being provided with a means for