JPS6192120A - Inspection system of pull-out detecting circuit - Google Patents

Abstract

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

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an inspection method for an out-of-synchronization detection circuit of a protective relay device.

[Technical Prelude to the Invention] Various types of protective relays have been used as protective relays to protect power systems, but they are easy to apply to power systems, are reliable, and have the advantages of 11! Distance relays are often used because they operate in 1q. This distance relay introduces phase current or line voltage and line current into the power system's phases, measures the line impedance to the fault point, and determines the distance and direction to detect a fault. This is what I did.

By the way, in a protective relay device using this distance relay, an unnecessary response may occur not only due to a system failure but also due to a loss of synchronization. In other words, if synchronization occurs, the power phases between the generators cannot be synchronized.

Each generator will operate at its own rotational speed, and the voltage phase between each generator will repeat the same phase and opposite phase, and for this reason, distance relays that input voltage and current will not be able to get out of synchronization as an accident. There is no need to misunderstand and react. For this reason, if the distance relay is configured to send a tripping command to the circuit breaker, an error or [Fi] may occur when synchronization is lost. However, when out of synchronization, the voltage and current change gradually, and in the event of an accident, they change suddenly, so this is used to detect out of synchronization, and the tripping circuit using the distance relay is locked by this output. In this case, the out-of-synchronization detection method doubles as the Moe element of the distance relay, and off-series l-E-
The out-of-synchronization detection circuit is configured by a combination of 92 elements.

FIG. 3 is a diagram showing the configuration of this type of general out-of-synchronization detection circuit. In the figure, 1t
2 is an offset seven elements, 3.9 is a NOT circuit, 4 is an OR circuit, 5.10 is an AND circuit, 6 is an out-of-synchronization detection timer, 7 is a flip-flop circuit, 8 L;
L is a relay that operates upon detection of out-of-synchronization, 11 is a lit device for issuing a trip command to a breaker using a distance relay, and A is a 11
Disconnection detection circuit inspection signal B is distance relay high output.

FIG. 4 shows the operating characteristics (ranges) of the Maw element 1 and the offset Maw element 2, which are the constituent elements of FIG. 3, in an RX diagram. In FIG. 4, A shows the load impedance point of the power transmission line during normal times, C shows the impedance of the power transmission line, C shows the impedance at the fault point within the protection range, and 2 shows the impedance locus when out of synchronization.

The out-of-synchronization detection circuit will be explained below with reference to FIGS. 3 and 4. The out-of-synchronization detection circuit shown in FIG. 3 detects out-of-synchronization by utilizing the difference in transition time of the impedance locus at the time of a system fault and at the time of out-of-synchronization. In other words, in Fig. 4, first of all, in the event of a system fault, the impedance instantly shifts from the load impedance point A to the fault point.
operate at the same time, and the output of Mo element 1 is NOT circuit 3B!
, and are input to the AND circuit 5 via the OR circuit 4, so the AND condition does not hold. At this time, the out-of-synchronization detection circuit check signal A included in the OR circuit 4 is not output.

Therefore, the flip-flop circuit 7 is not set, and no out-of-sync detection is performed in this case.

Next, when out-of-synchronization occurs, the impedance locus 2 at the time of out-of-synchronization shown in FIG. 4 moves slowly on the RX diagram. At this time, first, the offset mode element 2 operates, and the 7-key circuit 1 does not operate, so the AND condition of the AND circuit 5 is established via the FF1-circuit 3, and the out-of-synchronization detection timer 6
starts callan 1-. When this 1iII Ill is out of sync, the 7-element 1 is
does not operate, so the signal enters the set side of the 1-tub circuit 7, and at this time Jul? T: Since the see element 2 is operating, it is inverted by the NOT circuit 9, and no signal is input to the reset side. Therefore, the flip-flop circuit 7 is set, and the output on the Q side is output. Even if the output B is output, the AND condition of the AND circuit 10 is not satisfied, and the PRLR device tripping command relay 11 does not operate due to the distance relay.

An inspection method for the out-of-synchronization detection circuit having such a configuration will be explained with reference to FIGS. 3, 4, and 5.

FIG. 5 shows a conventional inspection result determination circuit. C is the output of the relay 8 for out-of-synchronization detection, 12 is an AND circuit, and 13 is a timer for inspection determination.

Generally, the inspection point of the out-of-sync detection circuit is the fourth
In the figure, point C is set close to point f. With the start of inspection of the out-of-synchronization detection circuit, the motor element 1 and the offset motor element 2 are
A test voltage and a test current are applied such that the impedance seen is near the heel point. For this reason, the out-of-synchronization detection circuit will not operate as it is because the moor element 1 and the offset moor element 2 operate at the same time. Under the AND condition, the flip-flop circuit 7 is set after the settling time of the out-of-synchronization detection timer 6 has expired, and the out-of-synchronization detection relay 8 is operated wJ by outputting the Q side output. Therefore, if the out-of-sync detection circuit is functioning normally, an AND condition is established between the out-of-sync detection circuit inspection signal of the inspection result determination circuit in FIG. 5 and the output C of the out-of-sync detection relay 8, After the settling time of the inspection determination timer 13 has elapsed, it is determined whether the inspection is good. When the inspection is determined to be good, the inspection voltage and inspection current are returned to the grid voltage and grid current, and the impedance returns to the normal load impedance point A of the transmission line in Figure 2, so the moor element 1 and the offset moor element 2 are restored. Then, due to the return of the offset mode element 2, the node circuit 5
The AND condition is not satisfied, and the flip-flop circuit 7
At the same time that the set-side input is removed, the signal is input to the reset side of the flip-flop circuit 7 via the NOT circuit 9. Therefore, C and flip-flop circuit 7 are reset, and Q
The side output becomes <<<, the out-of-synchronization detection relay 8 is restored, its output C disappears, the AND condition of the AND circuit 12 is not satisfied, and the inspection good signal is restored. This ends the inspection.

[Problems with Background Art] The test result determination circuit 1: having the above configuration has the following problems. Although it can be determined that the out-of-synchronization detection circuit is functioning normally, what is important is that the output of the out-of-synchronization detection circuit reliably locks the breaker trip command by the distance relay. Therefore, the conventional inspection result determination circuit has a problem in that it cannot be determined from the output of the out-of-synchronization detection circuit whether the breaker tripping command by the distance relay is actually locked.

[Object of the Invention] The present invention has been made to solve the above-mentioned problems, and the output of the out-of-sync detection circuit reliably locks the jammer removal command by the distance relay when inspecting the out-of-sync detection circuit. By confirming that, when an out-of-synchronization phenomenon occurs in the grid, unnecessary tripping of the breaker will occur due to insufficient locking of the breaker tripping circuit by the distance relay due to out-of-synchronization detection. The purpose of this invention is to provide a highly reliable inspection method for an out-of-synchronization detection circuit that will never fail.

[M essential points of the invention] In the present invention, in the out-of-sync detection circuit inspection, the inspection result judgment output is performed under the condition that the breaker trip command by the distance relay is locked by the out-of-sync detection circuit output and the out-of-sync detection circuit output. By putting out the same! This is intended to confirm that the outer lock of the rl1gi device tripper is reliably locked by the distance relay by the output of the 1 disconnection detection circuit.

[Embodiments of the Invention] The first embodiment of the present invention will be described below with reference to FIG. 11, FIG.
This will be explained with reference to FIG. FIG. 1 shows an inspection result determination circuit for an out-of-sync detection circuit according to the present invention. D is the output of the relay 11 for commanding breaker trip using a distance relay.

Since the inspection method of the 1ii1 out-of-period detection circuit having such a configuration is as described above, the explanation will be centered on the inspection result determination circuit here. First of all 1. When the inspection of the out-of-synchronization detection circuit starts, a check voltage and a check current are applied to the motor element 1 and the offset motor element 2 so that the impedance seen by them becomes near the point, so the motor 22 element 1 operates and the distance relay is activated. Since the Q side output of the flip-flop circuit 7 is output until the output B is output and the out-of-synchronization detection timer 6 operates, the AND condition of the AND circuit 10 is satisfied, and the distance relay operates. The disconnector trip command relay 11 operates. Since the output of 11 is outputted, the inspection result determination circuit is outputted via the NOT circuit 14, so the AND condition of the AND circuit 12 is not satisfied. Next, the same II
After the settling time of the disconnection detection timer 6 has elapsed, the flip-flop circuit 7 is set, and its Q side output is output, the disconnection detection relay 8 is disconnected, and its output C is output. On the contrary, since the Q side output of the flip-flop circuit 7 disappears,
The AND condition of the AND circuit 10 is not satisfied, the distance relay interrupts the breaker, the command relay 11 returns to normal, and its output disappears. As a result, the AND condition of the AND circuit 12 is satisfied by the output C of the previous out-of-synchronization detection relay F3 via the knot circuit 14 and the out-of-synchronization detection circuit inspection signal Δ, and the setting time of the inspection judgment timer 13 is set. Judgment of good quality after post-inspection. The operations after the inspection is determined to be good are as described above.

FIG. 2 is a second embodiment according to the present invention. In FIG. 2, 15 and 17 are NOT circuits, 16 is a flip-flop circuit, and 18 is an AND circuit.

First, by starting the inspection of the out-of-synchronization detection circuit, as described in the first embodiment, the distance is 1! The relay 11 for disconnection and dexterity command operates, and the output of 11 is output, so that an input is input to the set side of the flip-flop circuit 1G, the flip-flop circuit 16 is set, and its Q side output is output. Setting of 1υ1 deviation detection timer 6 11. '
After l limit, the flip 1 norotube circuit 7 is set to cell 1~, and its Q
Since there is no side output, the AND line f1 of the AND circuit 10
is not established, and distance lol! The command relay 11 returns to its normal state due to the interruption of the electrical circuit breaker, and its output disappears. As a result, the AND condition A'1 of the AND circuit 18 is established with the Q side output of the previous flip-flop circuit via the NOT circuit 17. At this time, since the output C of the out-of-synchronization detection relay 8 is output, the AND condition of the AND circuit 12 is satisfied, and after the setting time of the inspection determination timer 13 has expired, it is determined that the inspection is good. The reason why the flip-flop circuit 16 and the knot circuit 17 are provided here is that when the inspection of the out-of-synchronization detection circuit starts, the breaker exception caused by the distance relay is activated, and the command relay 11 is activated once, and the out-of-synchronization detection timer 6 is set. Timed backward III
This is to confirm that the disconnection detection circuit output locks and restores the operation of the command relay 11 due to the breaker exception caused by the distance relay. When the inspection of the out-of-synchronization detection circuit is completed, the out-of-synchronization detection circuit inspection signal 8 disappears, so it is inputted to the reset side of the flip-flop circuit 16 via the NOT circuit 15, and the flip-flop circuit 16 is output.

Effect of the Invention 1 As explained above, according to the present invention, in the inspection method of the out-of-sync detection circuit, the distance Il! By adding the condition that the tripping command by the I relay is set, an extremely reliable protective relay device can be provided by simply adding a simple circuit.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram of an embodiment of an inspection result determination circuit used in the inspection method for an out-of-sync detection circuit according to the present invention; FIG. 2 is a diagram of an inspection result determination circuit according to another embodiment of the present invention;
The figures show a general out-of-sync detection circuit. 1. Schematic diagram, 4.
The figure is a characteristic diagram showing the operating ranges of the motor element and the offset motor element, and FIG. 5 is a conventional inspection result determination circuit diagram. 1...Mho element 2...Offset Moo element 3.9.14.15.11...NOT circuit 4...OR circuit 5.10.12.18...AND circuit 6...Synchronization Disconnection detection timer 7.16... Flip-flop circuit 8... Out-of-synchronization detection relay 11... Distance relay-based breaker exception command relay 13... Inspection judgment timer A... Out-of-synchronization detection Circuit inspection signal B...Distance 1 relay output C...Output D of the relay 8 for out-of-synchronization detection...Output of the relay 11 for tripping by the distance relay...Negative voltage of the power transmission line during normal times Odd impedance point entrance... Impedance of the transmission line... Fault point impedance within the protection range... Impedance locus at the time of synchronization loss (7317) Agent: Kensuke Norichika, patent attorney (and 1 other person) 1st Figure 3 Figure 4 Figure 3

Claims (2)

[Claims] (1) Distance to detect an accident and output a breaker trip command by introducing the voltage and current of the electric power system, which has a Maw element as a distance element and an offset Maw element having a wider operating range than the Maw element. a relay; and an out-of-synchronization detection circuit that detects out-of-synchronization and locks the breaker output with the output of the out-of-synchronization condition on the condition that the offset motor element is operated and the motor element is inoperative for a predetermined period of time or more. In the protective relay equipped with the above-mentioned protection relay, when inspecting the out-of-sync detection circuit, it is determined that the inspection is good after confirming that the breaker trip command of the distance relay is locked by the output of the out-of-sync detection circuit. Inspection method for out-of-sync detection circuit. (2) Distance to detect an accident and output a breaker trip command by introducing the voltage and current of the electric power system, which has a Maw element as a distance element and an offset Maw element having a wider operating range than the Maw element. a relay; and an out-of-synchronization detection circuit that detects out-of-synchronization and locks the breaker output with the output of the out-of-synchronization condition on the condition that the offset motor element is operated and the motor element is inoperative for a predetermined period of time or more. When the out-of-synchronization detection circuit was inspected, the relay for trip command using the distance relay was activated once, and the relay for trip command using the distance relay was restored by the output of the out-of-synchronization detection circuit, and the out-of-synchronization detection circuit An inspection method for an out-of-synchronization detection circuit, characterized in that the inspection is determined to be good on the condition that an output is output.