JPS6335124A - Directional comparison protective relay - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention relates to speeding up the trip time when carrying circuit inspection is added in a continuous transmission type protective relay device. .

(Prior Art) Although the present invention can be applied to either a direction comparison type protective relay device using power line transport or microcarrier waves, the following description will be made using power line transport as a representative.

It is well known that the direction comparison method performs internal/external determination by stopping the carrier wave by operating a relay that detects an internal direction fault, and transmitting the carrier wave by operating a relay that detects an external direction fault.

In addition, in this method, there is a constant transmission method in which the carrier wave is transmitted during normal times and when an accident in the external direction is detected, and the carrier wave is stopped when an accident in the internal direction is detected, and a constant transmission method in which the carrier wave is stopped during normal times and when an accident in the internal direction is detected and the carrier wave is transmitted in the external direction. It is also well known that there are two types of accident transmission methods, which transmit carrier waves in the event of an accident.

The present invention relates to a constant transmission method, which includes self-end internal detection relay operation and carrier wave stop (hereinafter referred to as
For simplicity, the trip is planned by "no reception"), so there is no need for time coordination with the other end, and this is an extremely useful method.

However, in order to improve the reliability of the protection system, it has become common to automatically monitor the protection relay device and peripheral devices. Therefore, in this system as well, the transport circuit is constantly monitored or automatically inspected. That is, in the constant transmission method, if there is no reception for a certain period of time under normal conditions, it is determined to be abnormal, and if carrier waves are continuously received, it is determined to be normal. Furthermore, automatic inspections are carried out to ensure that the carrier wave can be stopped in the event of an internal accident. In other words, a repeat inspection method is adopted in which the carrier wave is stopped from the terminal to be inspected, and the carrier wave is stopped at the terminal to be inspected.

Therefore, whereas originally, a non-reception would only occur in the case of an internal accident, a similar situation will occur in the case of automatic inspection.

For this reason, even in the constant transmission system, it has become necessary to coordinate time with the other end in the following cases.

Figure 6 shows a case where time coordination is required. In the figure,
1A and 1B are direction comparison relay devices installed at the A@ and B terminals, respectively. If the inspection is performed from the A terminal, the carrier wave stop is controlled from the direction comparison protection relay device 1A, and when the direction comparison protection relay device @lB of the B terminal receives no reception, the B terminal also stops the carrier wave. . The A terminal will confirm this, but if a grid fault occurs at point f behind the A terminal while both devices are stopping each other, the B terminal will stop the carrier wave for inspection and prevent the grid fault from occurring. It becomes impossible to distinguish it from carrier wave control.

In other words, if the A terminal's external direction relay operates and transmits a carrier wave, and the Bl element's internal detection relay operates before the B terminal's trip is locked, the B
The terminal will be mis-tripped.

(Problems to be Solved by the Invention) In order to prevent this, a time coordination circuit shown in FIG. 7 is required. In the figure, 2 is an internal accident detection relay, 3 is an on-delay timer, 4 is an AND circuit, and timer 3
By adding this, even in the case described above, time coordination is taken into consideration to ensure trip locking due to re-oscillation at the other end.

Therefore, the time limit T1 of the cooperative timer 3 is as shown in FIG.
It can be decided.

As shown in the figure, if an external accident occurs at the inspection starting end while the carrier waves are being stopped for inspection, carrier wave oscillation is controlled by the accident detection relay operation at the inspection starting end. The end to be inspected receives this after the transmission delay time Td, but
If the internal direction detection relay is operating at this point, it is necessary to delay the trip command by timer T1 time. In other words, the following coordination will take place.

Timer T1>FX +Td-DIPUii.

Umax Here, FXPUIllax is the maximum operating time of the accident detection relay, Td is the transmission delay time, and DI is the internal P
Um+n is the minimum value of the accident detection relay.

By establishing such time coordination, the operation time of this device in the event of an internal accident is reliably delayed by the time limit of timer T1, as shown in Figure 9, but the operation time of this device in the event of an internal accident is reliably delayed by the time limit of timer T1. This occurs in order to prevent this.

As a result, the conventional apparatus has a problem in that it is difficult to avoid a delay in operation time.

The present invention has been made in view of the above-mentioned problems, and provides a direction comparison protection relay device that does not delay the operation time even in the event of an accident during non-inspection due to time coordination through inspection of the carrier circuit. The purpose is to

[Structure of the Invention] (Means for Solving the Problems) The structure for achieving the above object will be explained using FIG. 1 corresponding to the embodiment. A first circuit that configures a logical product by using the failure detection relay at its own end as an input for a certain period of time as input at the other end (
output of the inhibit circuit 7) and the output of the first circuit, and a second circuit (flip It consists of a flop 8) and a third circuit (output of the inhibit circuit 12) that configures a logical product with the operation of the self-end internal direction detection relay as one input and the output of the second circuit as the other inhibition input. , the trip command is generated under the AND condition of the output of the third circuit and no reception from the other end.

(Function) Therefore, the time coordination circuit is added by the second circuit only during inspection, and the time coordination circuit is excluded during non-inspection to enable high-speed tripping.

(Example) FIG. 1 shows an example of the present invention. Circuits similar to those in Fig. 7 are given the same symbols, 5 is an accident detection relay, 6.1
0 is an on-delay timer, 7.12 is an input circuit, 8 is a flip-flop, 9 is a NOT circuit, 11.
13 is an OR circuit.

In the figure, flip-flop 8 is fault-free, i.e.
If no reception is received when the accident detection relay is not operating, it is assumed to be an inspection signal and is set. Flip
When the flop is set, an inhibit input is applied to the inhibit circuit 12 to lock the instantaneous trip circuit of the internal fault detection relay 2.

In this case, a trip command is given via the time coordination timer 3 as in the conventional device.

On the other hand, during non-inspection, the system is always sending out, so it is in a receiving state. At this time, if an internal accident occurs, the accident detection relay 5 operates, and after the time limit Tz of the timer 6 has elapsed, an inhibit input is given to the inhibit circuit 7. Thereafter, the internal detection relay at the other end operates to detect no reception. Also, flip-flop 8 is not set.

Therefore, since the output of the inhibit circuit 12 becomes valid, the AND circuit 4 can immediately issue a trip command when the internal fault detection relay 2 operates and no reception is established.

Note that the NOT circuit 9, the on-delay timer 10, and the OR
The circuit 11 is a circuit that resets the flip-flop when the flip-flop 8 is set during the above-mentioned inspection, after the inspection is completed or when the other end becomes the idle end, and is used to reset the flip-flop in the event of a subsequent internal accident. It is provided to enable tripping.

Here, the necessity of the timer 6 and the basis of its time limit T2 will be explained with reference to FIG.

Generally, the internal detection relay at the other end operates, and the fault detection relay at the own end operates faster than when no reception is received, but a timer 6 is provided assuming the worst case of reversal. Here, the time limit T2 of the timer 6 is determined as follows.

Timer T2 >Ta +TFX Here, Ta is the above-mentioned transmission delay time, and TFX is the maximum value of the difference in operating time between the fault detection relay at the own end and the fault detection relay at the opposite end. In other words, the flip-flop 8 is set reliably even if an inspection and an external fault occur almost simultaneously, and the fault detection relay at the inspection starting end operates slowly and the fault detection relay at the inspected end operates quickly. By delaying the inhibiting power of the inhibit circuits 1 to 7, mistrips are prevented.

Next, the operation of the circuit of the present invention will be explained for each case using FIGS. 3 to 5.

Figure 3 shows a case of an internal accident during non-inspection.

In this case, the other end performs internal detection and receives this at its own end, resulting in a trip.

Here, the flip-flop 8 is time-coordinated with the above-mentioned timer 6 so that the conditions 1 to 1 are satisfied after the self-end trip condition is satisfied, so that the trip time is not affected.

Figure 4 shows a case of an external accident at the inspection starting end during inspection. In this case, the inspection start end detects the accident, controls the re-oscillation,
When the inspection target ◇ receives this, the flip-flop 8 is set, so the instantaneous trip is locked. Timer 6 (T2) operates after receiving the re-transmission, so there is no chance of a mistrip.

Figure 5 shows a case of an internal accident during inspection. in this case,
Flip-flop 8 is set to Sera 1 without reception due to inspection.
Therefore, even if no reception by the internal detection relay of the inspection start terminal continues, the trip condition of the own end is satisfied only after the timer 3 (T+) is activated.

[Effects of the invention] As described above, by providing a circuit that distinguishes between no reception during inspection and no reception due to a system failure, trip time during non-inspection can be shortened, and unnecessary operations can be avoided due to an accident during inspection. Therefore, it is possible to provide a direction comparison protection relay device that does not require any damage.

[Brief explanation of the drawing]

Fig. 1 is a circuit diagram showing an embodiment of the present invention, Fig. 2 is a time chart explaining the necessary conditions of the present invention, Fig. 3 is a time chill route explaining an internal accident during non-inspection, and Fig. 4 is a time chart to explain an external accident at the inspection start end during an inspection, Figure 5 is a time chart to explain an internal accident during an inspection, Figure 6 is a system diagram to explain time coordination, and Figure 7 is a conventional diagram. The circuit diagram of the device, FIG. 8 is a time chart explaining the time coordination timer, and FIG. 9 is a time chart explaining the operation of the conventional device. 1A, 1B...Direction comparison protection relay device 2...Internal fault detection relay 3.6.10...ON-delay timer 4...NO
Circuit 5... Accident detection relay 7.12... Inhibit 1-circuit 8... Flip-flop 9... NO circuit 11.13... OR circuit

Claims (1)

[Claims] In a direction comparison protection relay device with a constant sending method that has a conveyance circuit inspection function, one input is no reception from the other end, and the other input is the failure detection relay at the own end that is inoperable for a certain period of time, and a logical product is performed. a first circuit constituting the circuit, a second circuit constituting a memory circuit that is set by the output of the first circuit and reset on the condition that there is oscillation from the other end or that the other end is stopped; A third circuit constitutes a logical product with the operation of the detection relay as one input and the output of the second circuit as the prohibition input of the other, and the output of the third circuit and the signal not received from the other end. A direction comparison protective relay device characterized by increasing the trip time by issuing a trip command under a logical product condition.