JPS6252538B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a protective relay device for protecting an electric power system, and particularly to an improvement in its automatic monitoring system.

Traditionally, various types of protective relay devices have been used to protect power systems, but recently devices equipped with automatic monitoring circuits have been introduced with the main purpose of improving reliability and saving labor for maintenance. It is widely adopted. Further, as is well known, this automatic monitoring method is classified into a constant monitoring method mainly aimed at discovering defects on the malfunction side and an automatic inspection method mainly aimed at discovering defects on the malfunction side.

By the way, in the protective relay device equipped with the automatic monitoring circuit as described above, in addition to displaying an alarm when the constant monitoring fails, there is a type that locks the device to prevent malfunction in the event of an external accident. Widely adopted. Hereinafter, a conventional protective relay device equipped with a typical automatic monitoring circuit will be described with reference to the drawings.

1 to 4 show the circuit configuration of such a conventional protective relay device. First, Figure 1 shows the constant monitoring (defect detection) circuit and the automatic inspection result confirmation circuit, and the main relays are 1, 2, 3, and 4.
This is about a device consisting of. 1st
In the figure, S1, S2, S3 and S4 are main relays 1 to 4, which are applied to an OR circuit 5. 6
is an on-delay timer which is activated by the output of the OR circuit 5 and has a time limit of _T1 , and 7 is an auxiliary relay for constantly monitoring the on-delay timer 6 to detect failures. 8 is each main relay output S1~
The inspection result confirmation circuit receives S4 as an input, and S8 is its output. In such a configuration, main relays 1 to
4 is defective and malfunctions, and the output of any one of S1 to S4 becomes "1", the output of the OR circuit 5 becomes "1" and excites the on-delay timer 6, and a certain period of time T ₁ elapses. Later, the output is sent out as "1" and the auxiliary relay 7 operates. on the other hand,
When an operation input is applied to main relays 1 to 4 during equipment inspection, if normal, the main relay to which this inspection input is applied operates and one of its outputs S1 to S4 becomes "1". , this output is judged by the inspection result confirmation circuit 8 as to whether it is good or bad.

FIG. 2 shows the configuration of the inspection activation and inspection input application circuit. In the figure, 11 is an automatic inspection activation condition circuit, 12 is a manual inspection activation condition circuit, and their respective outputs are applied to an OR circuit 13. 14 is an inspection input power supply circuit controlled by the output of the OR circuit 13;
15a to 18a are normally open contacts of auxiliary relays for applying inspection inputs controlled by a step circuit (not shown), and inspection inputs are applied to main relays 1, 2, 3, and 4 from the inspection input power supply circuit 14, respectively. I try to do that.

In such a configuration, for example, when the output of the automatic inspection starting condition circuit 11 becomes "1", the OR circuit 1
3 becomes "1", and the inspection power supply circuit 14 is controlled. Further, when the inspection is started and the trip circuit is locked by the circuit described later, the auxiliary relay 15 for applying inspection input (main relay selection) is operated, and its contact 15a is "closed", causing the main relay 1 to operate. Input is applied. When the main relay 1 operates due to the application of this inspection input, its output S1 becomes "1", and this is applied to the inspection result confirmation circuit 8 in Fig. 1, and when the output S8 becomes "1", it is determined that the operation is "good". , the auxiliary relay 15 is reset to release the application of the inspection input. Also, this main relay 1
Auxiliary relay 1 provided that the inspection is “good”.
6 and closes the contact 16a to close the main relay 2.
A check input is applied to. Thereafter, the responses of main relays 2 to 4 are confirmed in the same manner.

Fig. 3 shows the configuration of the trip circuit, including contact 21a of the auxiliary relay that amplifies the output of main relay 1, contact 22a of the auxiliary relay that amplifies the output of main relay 2, and contact 22a of the auxiliary relay that amplifies the output of main relay 3. contact 23a of the auxiliary relay to amplify the output of the main relay 4, contact 24a of the auxiliary relay to amplify the output of the main relay 4, and normally open contact 32 of the auxiliary relay 32 to lock the trip circuit.
a. The control power supply bus _P1 is constructed as shown in the figure.
In other words, the configuration is such that the trip command output Tp is sent out under the conditions of the operation of the auxiliary relay 32 and the operation of the main relays 1 and 2 or the main relays 3 and 4. The AND configuration of contacts 21a and 22a or the AND configuration of contacts 23a and 24a in FIG. 3 is to prevent unnecessary disconnection due to malfunction of one main relay.

FIG. 4 shows the configuration of the control circuit of the trip lock auxiliary relay 32, and in the figure, 31a
and 31b are the normally open and normally closed contacts of the auxiliary relay 31 (not shown) that operate during inspection, 33a ₁ and 33b are the normally open and normally closed contacts of the auxiliary relay 33, and 32O and 32R are the respective operating coils of the keep relay 32. , and a reset coil, and 32T is a transfer contact of the keep relay 32.
Further, 7a is a normally open contact of the auxiliary relay 7, and 33
is an auxiliary relay, 33a ₂ is a normally open contact of the auxiliary relay 33, and 34b is a normally closed contact of a push button switch 34 (not shown), which are arranged between control power bus lines P ₂ and N as shown.

Next, based on FIG. 3 and FIG. 4, the trip lock sequence operation during automatic inspection and when constant monitoring fails will be described. First, the auxiliary relay 31 is activated by the current inspection activation, and its contacts 31a are closed, contacts 31b are opened, and the reset coil 3 of the keep relay 32 is activated.
When 2R is energized, the keep relay 32 returns, its contact 32a is "open", and the trip circuit is locked. When the inspection is completed as described above, the contact 31a is "open" and the contact 31b is "closed", thereby exciting the operating coil 32O of the keep relay 32, operating the keep relay 32, and releasing the trip lock.

Next, when the constant monitoring is defective, the auxiliary relay 7 shown in FIG. 1 is operated, and its contact 7a is "closed" to operate the auxiliary relay 33, which is self-held by its contact _33a2 . (The self-holding state of the auxiliary relay 33 is released by operating the pushbutton switch 34 to open the contact 34b.) When the auxiliary relay 33 operates, the contact 34b
b "open", 33a ₁ "close", reset coil 3
2R is excited to return the keep relay 32.
When the keep relay 32 is restored, the contact 32a in FIG. 3 is "opened" and the trip circuit is locked. When the constant monitoring failure is recovered, the contact 7a is opened, and the push button switch contact 34b is manually opened to restore the auxiliary relay 33, and the contacts 33b are closed and the contacts _33a are opened. The trip lock is released by operating the keep relay 32.

By the way, in a protective relay device equipped with an automatic monitoring circuit as described above, when a failure occurs through constant monitoring, a warning is displayed by a lamp or the like to that effect, and then the quality of the device is determined manually, and if there is a failure, the failure is detected. After repairing the parts, the device is unlocked by a push button switch 34. Therefore, in such an automatic monitoring system, it is necessary to manually unlock the device in the following cases, and this poses many problems from the viewpoint of maintainability, especially in unmanned electrical stations.

(1) When there is an abnormality in the transmission path of a carrier relay device, etc., resulting in a constant monitoring failure.

(2) When the main relay operates due to special operations, resulting in constant monitoring failure.

In other words, (1) and (2) above are not originally due to a defect in the protective relay device, but the lock on the device may be released when the direct cause of the continuous monitoring defect is removed.
Furthermore, it is no longer necessary to manually judge whether the device is good or bad.

The present invention has been made in view of the above-mentioned circumstances, and its purpose is to provide a protective relay device that can save labor in maintenance and improve reliability of the device.

An embodiment of the present invention will be described below with reference to the drawings. 5 to 7 show configuration examples of the protective relay device according to the present invention, and in the figures, the same parts as in FIGS. Only the different parts will be described here. First, FIG. 5 shows the configuration of a constant monitoring defect detection and inspection result confirmation circuit. In other words, _FIG. 51, an AND circuit 53 is added which inputs the output of the NOT circuit 52, the off-delay timer 51, and the output of the ON-delay timer 6 obtained via the NOT circuit, and the output S5 of the AND circuit 53 is
3 is configured to be sent out as a constant monitoring failure recovery detection output.

FIG. 6 shows the configuration of the inspection start-up and inspection input application circuit. In other words, this circuit is connected to the output S5 of the AND circuit 53 in the OR circuit 13 in FIG.
3 is additionally input as an inspection start condition signal.

FIG. 7 shows the configuration of the control circuit of the auxiliary relay for trip lock. In other words, this circuit is used to replace the pushbutton switch contact 34b in FIG. A contact point 71b is provided.
Here, the auxiliary relay 71 is configured to be driven when the automatic inspection result (based on the signal S53) is good, that is, all the main relays 1 to 4 are "good." The configuration of the trip circuit is exactly the same as the conventional circuit shown in FIG.

Next, the response of the protective relay device configured as described above will be described. Note that the response during automatic inspection is the same as in the conventional case described above, and therefore the explanation thereof will be omitted.

[A] First, if constant monitoring becomes defective due to an abnormality in the transmission line or special operation, we will respond as follows.

In this case, due to a constant monitoring failure (for example, the main relay 1 malfunctions), the output of the OR circuit 5 becomes "1" and the output of the on-delay timer 6 becomes "1" after T ₁ hour.
The auxiliary relay 7 operates to "close" the contact 7a in FIG. 7, and the auxiliary relay 33 operates and is self-maintained by closing its contact _33a2 .
Due to the operation of this auxiliary relay 33, the contact 33b is "opened" and the contact 33a ₁ is "closed" at the same time, returning the keep relay 32 to the contact 3 shown in FIG.
2a is "open" and the trip circuit is locked.

Next, when the main relay operation recovers due to a transmission line abnormality or special operation that is the direct cause of the continuous monitoring failure (for example, main relay 1 returns), the output of the OR circuit 5 becomes "0", and the on-delay timer is activated. The output of 6 becomes "0" and the auxiliary relay 7 is reset. At the same time, the off-delay timer 51, the NOT circuit 52, and the AND circuit 53 operate for a certain period of time _T2 after the output of the on-delay timer 6 becomes "0".
In the AND circuit 53, the AND condition is satisfied for a certain period of time _T2 , and the output S53 becomes "1", which is added to the OR circuit 13 in FIG. 6 to start automatic inspection.

As a result, even if the inspection is carried out in the same manner as described above, there is no problem with the main relay, and since the inspection results are (all) "good," the auxiliary relay 71 operates and its contacts 71
b is opened, the self-holding of the auxiliary relay 33 is released, and the auxiliary relay 33 returns to its original state.
When this auxiliary relay 33 returns, its contact 33b is "closed" and its contact _33a1 is "opened", so that the operating coil 32o of the keep relay 32
is excited and the keep relay 32 operates.
When the keep relay 32 returns to its original state, the contact 32a shown in FIG. 3 is "closed" and the lock of the trip circuit is released.

[B] Next, when a constant monitoring failure occurs, but the failure content is semi-defective and returns to the original state, the following response is taken.

In this case, the keep relay 32 is reset and the trip circuit is locked due to a constant monitoring failure as in [A] above.

When the defective contents are restored, the output of the OR circuit 5 becomes "0" and the on-delay timer 6
The output of S53 becomes "0", a one-shot output is obtained by the off-delay timer 51, the NOT circuit 52, and the AND circuit 53, and the condition is satisfied in the AND circuit 53, so that the output S53
is “1” for a certain period of time T ₂ and the OR circuit 1
3 and automatic inspection is activated.

By carrying out this inspection, it is possible to detect most semi-defective contents during inspection, and even in the case of something that cannot be detected during inspection, there is no problem with the operation of the equipment because the inspection is judged as "good". considered as a thing. Therefore, inspection was “good”
At times, the auxiliary relay 71 operates, the auxiliary relay 33 returns, and the keep relay 32 operates to release the lock on the trip circuit.On the other hand, when the inspection is "defective", the auxiliary relay 71 is inoperative, and the trip circuit is unlocked. The lock continues.

As described above, in the protective relay device which is equipped with an automatic monitoring circuit having constant monitoring and automatic inspection functions and which locks the device when a constant monitoring failure is detected, the off-delay timer 51 and the not circuit 52 are
When the circuit consisting of the AND circuit 53 constantly monitors and detects failure recovery, this detection signal S53 activates the automatic inspection function to carry out an inspection, and the auxiliary relay 71 determines that the inspection result is "good". It is configured to add a function to unlock the device under the condition that the device has been locked.

Therefore, even if the protective relay device becomes constantly monitored due to an abnormality in the transmission line or special operation, there is no longer a need for manual testing to investigate the failure, and a simple circuit can be added. In addition, it is possible to quickly unlock the device based on the defect, and it is possible to obtain a protective relay device that is effective in saving labor for maintenance of the device and has extremely high reliability.

It goes without saying that the present invention is not limited to the above-mentioned embodiments, and can be implemented with various modifications without changing the gist thereof.

As described above, according to the present invention, it is possible to provide a protective relay device that can save labor on maintenance and improve reliability of the device.

[Brief explanation of the drawing]

Fig. 1 shows a conventional constant monitoring defect detection circuit and an inspection result confirmation circuit, Fig. 2 shows an inspection starting circuit and an inspection input application circuit, Fig. 3 shows a trip circuit, and Fig. 4 shows a conventional constant monitoring defect detection circuit and an inspection result confirmation circuit. FIGS. 5 to 7 are diagrams showing the configuration of a control circuit of an auxiliary relay for a trip lock, and are schematic configuration diagrams showing an embodiment of the present invention. 1, 2, 3, 4... Main relay, 5, 13... OR circuit, 6... On-delay timer, 51...
Off-delay timer, 53...AND circuit, 5
2...Knot circuit, 8...Inspection result confirmation circuit,
7, 33...Auxiliary relay, 32...Keep relay for trip lock, 11...Automatic inspection starting condition circuit, 12...Manual inspection starting condition circuit, S53...
Inspection start condition signal at the time of regular monitoring recovery, 15, 16, 1
7, 18...Auxiliary relay for applying inspection input, 34...
...Push button switch, 71...Auxiliary relay for inspection good judgment, 21, 22, 23, 24...Auxiliary relay for main relay output amplification.

Claims (1)

[Claims] 1. In a protective relay device that is equipped with an automatic monitoring circuit that has constant monitoring and automatic inspection functions, and locks the device when a constant monitoring failure is detected, an automatic inspection is performed when a constant monitoring failure is recovered, and the inspection results are reported. 1. A protective relay device characterized in that the device is unlocked on the condition that the device is determined to be in good condition.