JP2507363B2 - Busbar protection relay - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Object of the Invention (Industrial field of application) The present invention is a busbar protection joint adapted to introduce an LS condition for enabling selective protection of busbars composed of multiple busbars. The present invention relates to electronic devices.

(Prior Art) Generally, a single bus system or a double bus system is adopted as a bus configuration of an electric station. Compared to the single-bus system, the double-bus system does not require a power outage at the power station when switching loads, inspecting equipment, etc.In addition, in the event of a bus accident, it is possible to minimize power supply failures. For this reason, it is widely used in important electric power stations.

On the other hand, the bus relay protection relay method is selected according to the bus configuration or the bus operation method. In the double bus system, a method of performing selective cutoff is adopted in order to stabilize the system and reduce the supply hindrance.

FIG. 3 shows the selective protection when the busbar configuration is the double busbar system.

In FIG. 3, reference numerals 1 and 2 are bus bars, and 11, 21, 31, and 41 are circuit breakers of power transmission lines or transformers, and each of the disconnectors 1A and
Connected to the busbar via 1B, 2A and 2B, 3A and 3B, 4A and 4B. Reference numeral 51 indicates a busbar breaker, which connects busbars 1 and 2 with LSs 5A and 5B.

 A, B, and C indicate the protection range of the busbar protection device.

In the case of the busbar configuration shown in Fig. 3, LS1A and 1B are normally operated "open" except when switching the system.
The circuit breaker 11 is connected to the bus bar 1 or the bus bar 2.

LS2A, 2B and LS3A, 3B and LS4A, 4B are the LS1A, 1B
Similarly, one is operated in the "open" state.

A busbar protection method in such a configuration will be described. When an accident occurs on the bus bar, it is necessary to break all the circuit breakers connected to the accident bus bar. Now, in FIG. 3, LS1A, 2B, 3A, 4B are "closed", and LS1B, 2A,
Assuming that 3B and 4A are “open”, for example, when an accident occurs in the bus bar 1, the bus bar 2 can be operated as it is by shutting off the circuit breakers 11, 31 and 51.

Further, if the LS1A and 3A are manually set to “open” and the LS1B and 3B are set to “closed”, the circuit breakers 11 and 31 can be utilized and only the busbar 2 can be operated. In order to realize the above, the busbar protection device has a busbar range as shown in FIG.

That is, the busbar range A detects an accident on the busbar 1, and the busbar range B detects an accident on the busbar 2. Therefore, this method is called a split protection method.

On the other hand, the busbar range C detects an accident on both the busbar 1 and the busbar 2, and is called a collective protection system. Since the breaking command to the breaker is output by AND of the batch protection device and the split protection device, it is possible to surely perform selective breaking.

FIG. 4 is a diagram specifically showing the selective protection system of FIG.

In FIG. 4, the names other than the following are the same as those in FIG. CT1-4 and CT11, 21, 31, 41, 5
1, 52 are current transformers, 1A-a is a contact of LS1A, 1B-a
Indicates the a-contact of LS1B. Below, 2A-a, 2B-a, 3A-
Similarly, a, -a, 4A-a, and 4B-a are the a of the corresponding LS, respectively.
It is a contact point.

301 is a collective protection relay, 101 is a split protection relay that detects an accident on bus bar 1, and 201 is a split protection relay that detects an accident on bus line 2.

In order for the split relay to accurately perform selective protection, only the information of the line or transformer connected to the bus must be input to the split relay of the bus. As a method therefor, a method of detecting which of the busbar 1 or the busbar 2 is connected depending on the open / closed state of the LS is adopted. Therefore, a circuit for introducing the contact of the LS into the protection device and automatically switching the inputs to the split protection relays 101 and 201 is provided.

For example, if LS1A is "closed" and 1B is "open," bus 1
Since 1A-a is connected, the circuit is closed and input to the split protection relay 101.

In addition, as the relay system in the case of FIG. 4, generally, the collective protection relay 301 is a voltage differential relay system, the split protection relay 1
The current ratio differential relay system is adopted for 01 and 201, but the protection system itself is not what the present proposal intends, and therefore the description is omitted.

FIG. 5 shows a cutoff command circuit, and 301-a is a contact for operation output of the collective protection relay 301, 101-a, 201.
-A is a contact for operation output of the split protective relays 101 and 201, respectively, 1A-a, 1B-a, 2A-a, 2B-a, 3A-a, 3B-
Reference characters a, 4A-a, and 4B-a indicate the corresponding a contacts of the LS.

In FIG. 5, for example, in the cutoff command circuit of CB11,
If the LS1A is operated in the "closed" state and the LS1B is in the "open" state, and if an accident occurs on the busbar 1 side, the collective protection relay 301
The split protection relay 101 operates and issues a cutoff command under the AND condition of 301-a, 101-a and LS condition 1A-a.

On the other hand, an accident occurred on the bus 2 side and the collective protection relay 301
Although the split protection relay 201 of 1 operates, the cutoff command is not issued because 1B-a of LS is “open”. Therefore, the operation can be continued while being connected to the bus bar.

As described above, in the busbar protection method in the double busbar configuration, it is necessary to introduce the LS condition in order to enable selective protection and surely interrupt only the circuit breaker on the accident busbar side.

The content described so far is the case of the so-called 1CB2LS method in which two LSs are connected to 1CB, but the so-called 2CB3LS method, in which three LSs are connected to 2CB, has been adopted in recent compound busbars. ing. This 2CB3LS method (hereinafter referred to as 1 1 / 2LS method) has the merit that one LS can be reduced compared to the 1CB2LS method (hereinafter referred to as 2LS method).
The 1 / 2LS method is expected to increase.

Figure 6 shows the bus configuration using the 1 1 / 2LS method. Third
LS1C and 2C are added to the 2LS in the figure or FIG. 4, and the circuit breaker 11 of the feeder is between the LS1A and 1C, and the circuit breaker 21 is
Connected between 1B and 1C. In this case, LS1A and 1B are usually operated in the "closed" state, and LS1C is in the "open" state. The busbar selective protection relay system is exactly the same as the 2LS system. Can be

(Problems to be solved by the invention) In the 2LS method and the 1 1 / 2LS method described above, when viewed from the same number of feeders, not only the difference in the number of LS but also the condition to input to the split protection relay is different. come. For this reason, the 2LS and 3LS methods use the LS installed in the protective relay.
In order to input the conditions to the split protection relay, it is necessary to provide a dedicated circuit for each, and change the system condition (for example, 2L
There is a problem that it is necessary to change the internal circuit of the protective relay device every time from S to 1 1 / 2LS.

The above problems will be further clarified with reference to FIGS. 7 and 8. 7 and 8 show an LS condition switching circuit incorporated in the protective relay device.

FIG. 7 shows the case of the 2LS system, which is 1A-a, 1A-b, 1B.
-A, 1B-b, 2A-a, 2A-b, 2B-a, 2B-b are the corresponding a contact or b contact of LS1A, 1B, 2A, 2B, respectively. PC1 to PC8 are photocouplers, 401 to 404 are LS a contacts,
B-contact mismatch detection circuits, A1 and A2 are input signals to the busbar 1 side, and B1 and B2 are input signals to the split protective relays on the busbar 2 side. Then, the split protection relay 101 of the busbar 1 respectively corresponds to the feeders (A1: A1) depending on whether the outputs of A1 and A2 are established.
It is detected whether or not the line drawn out by the circuit breaker 11 in FIG. 3, A2: the line drawn out by the circuit breaker 21 in FIG. 3) is connected to the bus bar 1, and the feeder connected to the bus bar 1. Using the electric quantity signal (current quantity) of, the accident in the protection range A is detected. The same applies to the split protection relay 201 of the bus 2.

FIG. 8 shows the case of the 1 1 / 2LS system, and 1A-a, 1A-b, 1B-a, 1B-b, 1C-a and 1C-b are the same as in FIG.
LS a contact and b contact are shown. PC9 to PC14 are photocouplers, 405 to 407 are LS a contact and b contact mismatch detection circuits,
Similar to FIG. 7, A1, B1, A2, and B2 indicate AND circuits, and AND1 and AND2 indicate AND circuits.

As shown in Fig. 4, there is a method of amplifying and using the LS condition with the auxiliary relay contact, and a method of amplifying and using with the photocoupler as shown in this figure. This phenomenon is possible with either method. However, an example of a photo coupler will be described here. In addition, in FIG. 7 and FIG. 8, photocouplers PC2, PC4, PC6, PC8, PC for introducing the b contact signal of each disconnector
10, PC12, PC14 and the non-coincidence detection circuits 401 to 407 detect a failure of the disconnecting switch opening / closing signal from each disconnecting switch (when the a contact signal and the b contact signal match, this disconnecting switch opening / closing signal can be detected as a failure). It is provided to increase the reliability of the sushi device.

In Fig. 7, in the case of the 2LS method, the a contact of LS is each LS
Then, it becomes the input signals A1, B1, A2, B2 to the split protection relay through the photocouplers PC1, PC3, PC5, PC7. Input signal A
1 and A2 are input to the split relay of bus 1 and input signal B
1 and B2 are input to the bus 2 split relay.

On the other hand, in the case of the 1 1/2 LS system shown in Fig. 8, since the input signals B1 and A2 to the split relay are introduced, B1 is LS1A.
For the AND condition of IC and A2, it is necessary to build a circuit under the AND condition of LS1B and 1C.

In addition, the number of feeders is 2 in both Fig. 7 and Fig. 8, and the introduction amount is different between 2LS and 1 1 / 2LS due to the difference in the number of LS.
As described above, when changing the system condition, the internal circuit of the protection device also needs to be changed correspondingly, which is a drawback.

The present invention was made in order to solve the above problems, and provided an LS condition introducing circuit that can be used both when the bus configuration is 2LS and when it is 1 1 / 2LS, and an external cable to the protection device is provided. It is an object of the present invention to provide a busbar protection relay device that does not require a change in the internal circuit only by changing the connection of the.

[Structure of the Invention] (Means for Solving the Problems) In order to achieve the above object, in the present invention, an input circuit group for inputting a disconnector switching signal from each disconnector, and three disconnectors for a feeder. A group of conditioner introducing circuits provided as a set corresponding to each feeder, and the output of the first conditioner condition introducing circuit in each set as the first conditioner condition detection output, and others. A pair of disconnector condition detecting circuits for outputting the logical product output of the outputs of the two second and third disconnector condition introducing circuits as a second disconnector condition detecting output is provided corresponding to each feeder. When the disconnector condition detection circuit group and the busbar configuration are the 1 circuit breaker 2 disconnector system (2LS system), the input of the first disconnector condition introduction circuit is connected between the feeder and one of the busbars. Disconnector open / close signal of disconnector Wherein while connecting the second
And the input of the third disconnector condition introduction circuit is connected to the disconnector open / close signal of the disconnector connected between the feeder and another busbar, and the busbar configuration is 2 circuit breaker 3 disconnector system (1 1 / 2L
In the case of the S method), the input of the first disconnecting switch condition introducing circuit is connected to the disconnecting switch opening / closing signal of the disconnecting switch connected between the feeder and any one of the bus lines, and the second disconnecting switch condition introducing circuit is introduced. The input of the circuit is connected to the disconnecting switch opening / closing signal of the disconnecting switch connected between the feeder and the other feeder, and the input of the third disconnecting condition introducing circuit is connected between the other feeder and the other bus. A disconnecting switch opening / closing signal of the disconnecting switch, and connecting means capable of changing the connection according to the busbar configuration, and using the respective first and second disconnecting condition detecting outputs of the disconnecting condition detecting circuit group. A feeder connected to each busbar is detected, and a busbar protection relay device is provided in which the split protection relay performs selective protection using the electric quantity signals of the feeders connected to the same busbar.

(Operation) Therefore, the disconnecting switch open / close signal from each disconnecting switch is connected to each input circuit and each disconnecting condition introducing circuit by connecting means according to the bus configuration, and either 2LS system or 1 1 / 2LS system is selected. Can also be used in common.

Embodiment An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of an input circuit group, a disconnector condition introducing circuit group, a disconnector condition detecting circuit group and a connecting means which are applied to a busbar protective relay device according to the present invention. .

Fig. 1 shows the case of the 2LS system, and Fig. 7 shows the photo coupler P.
C21 and PC22, AND circuits AND3 and AND4 are added.

FIG. 1 shows a feeder drawn by a breaker 11 (hereinafter referred to as F1) and a feeder drawn by a breaker 21 (hereinafter referred to as F2) in the 2LS system bus line configuration of FIG.
For the other feeders, the same circuit is provided for other feeders. In FIG. 1, the disconnecting switch open / close signals from the disconnecting switches are the a contacts 1A-a to 2B-a of the disconnecting switches.
The input signals correspond to the contact signals from the b-contacts 1A-b to 2B-b and are input to the relay device, which are collectively referred to as an input circuit group. From the point of view of the present invention, it suffices to have a-contacts 1A-a to 2B-a for inputting a disconnecting switch opening / closing signal indicating "closing" of the disconnecting switch.

Further, here, three disconnector condition introduction circuits (photocouplers PC1, PC3, PC21) are provided as a set for the feeder F1. Those provided corresponding to the respective feeders (the photocouplers PC5, PC7, and PC22 for the feeder F2 are the respective disconnector condition introducing circuits) are collectively referred to as the disconnector condition introducing circuit group.

Then, for the feeder F1, the photo coupler PC1 (first
Output of photocoupler PC3 (second disconnector condition introducing circuit) and photocoupler PC21 (third disconnector condition introducing circuit) as the first disconnector condition detecting output A1. The logical product output of the second disconnector condition detection output
A disconnector condition detection circuit that outputs as B1 is provided
For F2, similarly disconnect as photocoupler PC7 (first disconnector condition introducing circuit), photocoupler PC5 (second disconnector condition introducing circuit) and photocoupler PC22 (third disconnector condition introducing circuit). A condition detection circuit. Then, those provided corresponding to the respective feeders are collectively referred to as a disconnector condition detection circuit group.

Next, when the bus line configuration is 2LS, the input of the first disconnector condition introducing circuit (photocoupler PC1) is connected to the feeder F1 between the feeder F1 and one of the bus lines by the connecting means. A disconnector which is connected to the disconnector switching signal of the disconnector (LS1A) and which is connected to the inputs of the second and third disconnector condition introduction circuits (photocouplers PC3 and PC21) between the feeder F1 and another bus. Connect to the disconnecting switch open / close signal of (LS1B). For the feeder F2, the input of the first disconnector condition introducing circuit (photocoupler PC7) is connected between the feeder F2 and either of the busbars.
2B) is connected to the disconnector switching signal, and the second and third disconnector condition introducing circuits (photocouplers PC5 and P)
The input of C22) is connected to the disconnecting switch switching signal of the disconnecting switch (LS2A) connected between the feeder F2 and another bus.

In Figure 1, the photo coupler that is subject to the LS condition is 2L.
Considering S use, there are 4 sets of receiving circuits, and photo couplers PC21 and PC22 are provided to create conditions for 1 1/2 LS.

In the case of 2LS in FIG. 1, the conditions of LS1A, 1B, 2A and 2B are received by PC1, PC3, PC5 and PC7, respectively, and the condition of LS1B is given to PC21 and the condition of LS2A is also given to PC22. The output of the photo coupler is the input of the split protection relay, the output of LS1A is the input signal A1, and the output of LS1B is the AND of the output of photo coupler PC21.
Input signal B1 at.

The output of LS2A is ANDed with the output of photocoupler PC22 to be the input signal A2, and the output of LS2B is used as the input signal B2.

Thus, in the case of the 2LS method, four sets of LS conditions are A1, A
Converted to 2, B1, B2 and input to the split protection relay.

As a result, with respect to the feeder F1, when the LS1A is closed and the LS1B is opened, the input signal A1 to the split protection relay on the side of the busbar 1
(First disconnector condition detection output) is established, while input signal B1 (second disconnector condition detection output) to the split protection relay on the bus 2 side is not established, so feeder F1 is connected to bus 1. Is detected, the split protection relay on the side of the bus 1 determines the operation using the amount of current flowing in the feeder F1 and performs selective protection.

FIG. 2 shows a block diagram of an embodiment when applied to the 1 1/2 LS system. FIG. 2 shows the feeder drawn out by the breaker 11 (hereinafter referred to as F1) and the feeder drawn out by the breaker 21 (hereinafter called F2) in the 1 1 / 2LS system bus line configuration of FIG. The circuit configuration is shown, and the same circuit is provided for other feeders.
2 shows the same configuration as that of FIG. 1 with respect to the input circuit group, the disconnector condition introducing circuit group, the disconnector condition detecting circuit group and the split protection relay even if the busbar configuration is changed. With the change of the bus line configuration, the number of disconnecting switch opening / closing signals becomes three for two feeders, and the connection between each disconnecting switch opening / closing signal of the input circuit of the connecting means and the disconnecting condition introducing circuit is only changed.

In FIG. 2, when the busbar configuration is 1 1 / 2LLS, the input of the first disconnector condition introducing circuit (photocoupler PC1) is input to the feeder F1 by the connecting means and the feeder F1 or one of the busbars. A disconnector that is connected to the disconnector switching signal of the disconnector (LS1A) connected in between and the input of the second disconnector condition introducing circuit (photocoupler PC3) is connected between the feeder F1 and another feeder F2. (LS1C) disconnecting switch open / close signal, 3rd disconnecting condition introducing circuit (photo coupler
The input of PC21) is connected to the disconnecting switch opening / closing signal of the disconnecting switch (LS1B) connected between the other feeder F2 and the other bus 2. For the feeder F2, the input of the first disconnector condition introduction circuit (photocoupler PC7) is connected to the disconnector switch signal of the disconnector (LS1B) connected between the feeder F2 and one of the busbars. The input of the second disconnector condition introduction circuit (photocoupler PC5) is connected to the disconnector open / close signal of the disconnector (LS1C) connected between the feeder F2 and another feeder F1, and the third disconnector condition introduction circuit A disconnector (LS) that connects the input of (photocoupler PC22) between another feeder F1 and another bus 1
Connect to the disconnector switching signal of 1A).

In Fig. 2, the condition of LS1A in Fig. 6 is the photocoupler.
The conditions of PC1, PC2 and LS1B are received by photocouplers PC7 and PC8.

Also, the condition of LS1C is that photo-couplers PC3 and PC5 are on the contact side a.
The b contact side is received by photo couplers PC4 and PC6.

In addition, the photocoupler PC21 has the a contact of LS1B and PC22 has
It is configured to receive the condition of the LS1A a-contact.

The input condition of the split protection relay is that the output of the photocoupler PC1 is the signal A1.

The output of AND3, which is the AND of PC3 and PC21, is signal B1,
The output of AND4, which is the AND of PC5 and PC22, is configured to be the signal A2, and the output of PC7 is configured to be the signal B2.

With such a configuration, it is possible to introduce the conditions of the respective feeders into the bus side divided protection relay to which the feeder conditions are connected.

As described above, the LS condition introduction circuit and the LS condition detection circuit are the same circuit for the 2LS method and the 1 1 / 2LS method, and can be easily changed by changing the connection of the external cable from the LS. It is possible to switch.

Therefore, when changing the system conditions, for example, change 2LS to 1 1 / 2LS
Even when changing to, it is not necessary to change the internal circuit of the protection device, the connection can be changed easily, and it is very useful in terms of standardization of the device.

In each of the above-mentioned embodiments, the connection change of the external cable is normally made at the terminal block, but this connection change can be made by a changeover switch.

[Effects of the Invention] As described above, in the present invention, whether the LS configuration of the bus bar is the 2LS system or the 1 1 / 2LS system,
It is possible to obtain a busbar protective relay device that can be easily switched without changing the internal circuit of the protective device and only by changing the connection of the external cable.

[Brief description of drawings]

FIG. 1 is an LS applied to a busbar protective relay device according to the present invention.
FIG. 2 is a diagram showing a case of a 2LS system in a configuration diagram of an embodiment of a condition switching circuit, FIG. 2 is a diagram showing a case of a 1 1 / 2LS system in another embodiment, and FIG. 3 is a selective protection system of bus bar protection. FIG. 4 is a diagram for explaining FIG. 4, FIG. 4 is a concrete embodiment of FIG. 3, and is a diagram in which a busbar protective relay is connected, FIG.
The figure shows the bus diagram configured by the 1 1 / 2LS system. Fig. 7 shows the LS condition and the introduction circuit of the conventional 2LS system. Fig. 8 shows the LS condition introduction circuit of the conventional 1 1 / 2LS system. It is the figure which showed. 1A, 1B, 2A, 2B, 3A, 3B, 4A, 4B, 1C, 2C …… Disconnectors PC1-8, PC21, PC22 …… Photocoupler 11, 21, 31, 41, 51 …… Breaker 301 …… Batch protection relay 101,201 …… Split protection relay CT1 to 4, CT11, CT21, CT31, CT41, CT51, CT52 …… Current transformer AND1, AND2, AND3, AND4 …… AND circuit 1,2 …… Bus

Claims (1)

(57) [Claims] 1. An electric station comprising a plurality of feeders connected to a compound busbar through a disconnector and a circuit breaker, respectively, wherein the electric quantity signals of the feeders connected to the respective busbars are divided into respective electric signals. In a busbar protective relay device for performing selective protection using a protective relay, an input circuit group for inputting a disconnector switching signal from each of the disconnectors, and three disconnector condition introducing circuits for the feeder as a set. The disconnector condition introduction circuit group provided corresponding to each feeder and the output of the first disconnector condition introduction circuit in each set are used as the first disconnector condition detection output, and the other two second and A disconnector condition detection circuit group provided in association with each feeder as a set of disconnector condition detection circuits that output the logical product output of the outputs of the third disconnector condition introduction circuit as the second disconnector condition detection output And this When the busbar configuration is the 1-breaker 2-disconnector system, the input of the first disconnector condition introducing circuit is connected to the disconnector switching signal of the disconnector connected between the feeder and one of the busbars. When the inputs of the second and third disconnector condition introducing circuits are connected to the disconnector open / close signal of the disconnector connected between the feeder and another busbar, and the busbar configuration is the two-breaker / 3 disconnector system Connects the input of the first disconnector condition introducing circuit to the disconnector open / close signal of the disconnector connected between the feeder and one of the busbars, and inputs the input of the second disconnector condition introducing circuit. Disconnection of a disconnector connected between the feeder and another feeder, connected to a disconnector switching signal of a disconnector, and the input of the third disconnector condition introducing circuit is connected between the other feeder and the other busbar. To connect to the open / close signal And connection means for connection change depending on the bus configuration, the disconnecting switch condition detection circuit each of the first and second groups
The feeder connected to each busbar is detected by using the disconnector condition detection output of, and the split protection relay performs selective protection using the electric quantity signal of the feeder connected to the same busbar. Busbar protection relay device.