JPS6248219A - Fm current operated relay system - 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 H current differential relay system for checking interconnection with the other end of a power transmission line.

[Technical Background of the Invention] FIG. 4 is a schematic diagram (not shown) of a well-known current difference 1FIJ relay type in which waveforms are transmitted by FM (frequency modulation) transmission. This current differential relay one-type type uses current transformers A and CTB installed at electric stations A and B at both terminals of the power transmission line 21.
Then, the line current 18, (B is transformed, and this output t^, tB
The relay operates according to the differential a obtained from l+ and l.

That is, the relays RYA and I' installed at electric stations A and B
The input amounts i, A, and tB to lYB are each input to the frequency conversion circuit 2.
28 and 22B, the signals are frequency-converted and transmitted to the other power station via respective transmission lines. △At the electric station, the frequency sent from electric station B is converted into current by the frequency conversion circuit 22A, and the output L from the current transformer CI8 at the top of the mountain.
A is input to the differential current detection circuit 23A, the differential amount is obtained from both inputs, and it is determined from this differential 1d whether or not the fault is within the protection zone.If the fault is within the protection zone, , to the trip signal T to shut off the circuit breaker CBA.

Similarly, at electric station 8, the frequency sent from electric station A is converted into current by frequency conversion circuit 22B.
Input the output tB from the source current transformation i5 CTB to the differential current detection circuit 23B, calculate the differential amount from both input products,
When it is determined that the accident is within the protected area, a trip signal 8 is issued and the edge breaker CBB is cut off.

In addition, in [H current differential relay one type], because the instantaneous value of the analog waveform is being transmitted, if a disturbance occurs in the transmission system and the accurate waveform cannot be transmitted, a difference current will occur.
If this value exceeds the operating value of the relay, it will lead to malfunction of the device. For this reason, a bounce disturbance detection circuit is provided in the one-type FM current difference a relay.

First, there is a circuit 26A12GB that detects disturbances in a signal transmitted from the other end via a current waveform transmission channel (hereinafter referred to as main channel).

The second method is to transmit constant frequency signals 25A and 25B to the other terminal via another channel (hereinafter referred to as noise-low channel) outside the main channel, and monitor the level of the H demodulated signal. Accordingly, there are circuits 24^ and 24B for detecting disturbances in the transmission system.

First, the disturbance detection circuits 268 and 26B of this channel
The detection output controls the disturbance detection circuits 24A and 24B for the noise lock channel, lowers the level of the constant frequency signal generators 25A and 25B, and connects the disturbance detection circuit 2 at the other end via the noise lock channel.
Operate 4A and 24B. Also, OR circuit 27^, 2
The differential current detection circuits 23A and 23B are locked through the differential current detection circuits 23A and 23B, and a lock detection signal [8 and 8B is output to the outside of the FM current differential circuits RYA and RYB.

By the way, many of the faults that occur in power transmission lines and distribution lines are non-continuous and the insulation can be restored if the fault current is quickly removed. By immediately re-closing the circuit after waiting for the insulation to recover, it is possible to continue power transmission by restoring the state to the state before the failure, so a re-closing function is often provided.

This reclosing method includes a single-phase reclosing method, a three-phase reclosing method, a single-phase three-phase reclosing method, and a polyphase reclosing method, depending on the phase to be cut off. Here, the single-phase reclosing method is a method in which the circuit is reclosed only when one phase fails, and is finally cut off when two or more phases fail.
The three-phase reclosing method is a method in which all three phases are cut off and all three phases are reclosed, and the single-phase three-phase reclosing method is a method in which a single phase is reclosed only when one phase fails, and three phases are reclosed when two or more phases fail. For example, in the polyphase reclosing method, the remaining two phases (2, 2,
This method recloses the circuit when the total line health phase condition is met.

For each of these methods, the optimum method is selected and applied based on the ffl'f degree of the system, the fault phase discrimination performance of the transmission line image 5 method, the purpose of reclosing, etc. In any of the re-closing systems, a problem arises in which the generator shaft is twisted by 1 to 1 lux. The phenomenon of shaft torsion torque of this generator will be explained below.

■ Power fluctuations (
electric torque fluctuation) occurs, which causes the shaft system t to vibrate with a unique torsional swing force frequency.

■Furthermore, when a power transmission line performs high-speed reclosing, sharp power fluctuations occur each time the line is opened and closed, and depending on the timing, the amplitude of shaft system vibration may gradually increase. Therefore, under adverse conditions when a reclosing circuit fails, the strength (torsional strength) of the @ material may be exceeded.Especially for the reclosing conditions of a multiphase reclosing circuit, the shaft torsional torque of the optoelectronic equipment must be carefully considered. Since the type of failure and whether or not reclosing is possible are determined, if the failure phase determination is incorrect, it will have a great impact on the shaft torsion 1 to 1 torque of the generator.

FIG. 5 is an example of a detection circuit for reclosing a one-phase or two-phase fault in a multi-phase reclosing method, with the condition that there are two or more healthy phases in the two circuits in total.

In the figure, 30 is an auxiliary relay for detecting breaker 2: all three phases are "off", 31 is an auxiliary relay contact for detecting breaker R phase "off", 32 is an auxiliary relay contact for detecting breaker S phase "off",
33 is an auxiliary relay contact for detecting breaker T phase “off”, 34
．． 35 and 36 are auxiliary relays that operate according to the above article f1, respectively;
30a, 34a, 35a, and 313a are a contacts of auxiliary relays 30, 34, 35, and 36, respectively, and 37 is an auxiliary relay for final cutoff detection. In this circuit, for example, when the own terminal side R', S2 phase failure is detected, two phases are cut off, and the other terminal side R',
If the failure detection mode differs between the own terminal side and the other terminal side, such as 3-phase cutoff during S and T 3-phase failure detection, 3-phase failure detection is performed systematically.
Despite the phase failure, re-closing is carried out on the own terminal side (because the other terminal side is a three-phase trip, a series circuit of contacts 34a, 35a, and 36a of the final disconnection detection circuit is configured, so (Re-closing is not carried out due to the operation of the final cut-off detection auxiliary relay 37), and in the event that the circuit is cut off again due to continued failure, etc., twisting of one sleeve of the generator connected to the system of its own terminal is permitted. It may be more than the torque. For this reason, in systems where the shaft torsion torque of the generator becomes a problem when such a malfunction occurs, a method is used in which the power flow conditions of the system are used to check the connection with the other terminal.

FIG. 6 is an example of a circuit when checking interconnection with a partner terminal. In the figure, 38 is b of the R-phase power flow detection relay.
The contacts 39 are the b contacts of the S-phase power flow detection relay, and 40 are the b contacts of the T-phase power flow detection relay.

The other circuits are the same as those shown in FIG.

When using this circuit, even if the R82 phase fails on the own terminal side and the R3T3 phase fails on the other terminal side, as in the case of the above problem, the power flow detection relay on the own terminal side will
Since all phases are "off", all three phases return to normal state, and their b contact 38.
39.40.3 Return. For this reason, the auxiliary relay 34.3
5.36 operates, the contact 34a of the final cutoff detection circuit,
Since a series circuit of 35a and 36a is constructed,
Re-closing is not performed due to the 01 operation of the final cut-off detection auxiliary relay 37. Of course, since the other terminal side is 3-phase cutoff, re-closing is not performed. In this way, by using the power flow conditions of the system in the final cutoff detection circuit of its own line, it is possible to provide a device that is excellent in stably supplying power.

[Problems with the background art] The conventional device having the above configuration has the drawbacks of requiring a power flow detection relay and requiring that the power flow of the system always be equal to or higher than the set value of the power flow detection relay. .

[Object of the Invention] The present invention has been made in order to solve the above-mentioned problems, and an object of the present invention is to provide an FM current differential relay system equipped with a more reliable interconnection confirmation means.

[Summary of the Invention] In order to achieve the above object, the present invention implements re-closing. [The level of the transmission signal of the H current differential relay is lowered, and the signal is determined by the FM current differential relay at the own terminal via the main channel of the H carrier, thereby turning off the breaker of the own terminal. This is detected and used to confirm interconnection with the other terminal.

[Embodiments of the Invention] Examples will be described below with reference to the drawings. FIG. 1 is an embodiment of the self-terminal breaker "off" signal transmission circuit applied to the "H current differential relay system" according to the present invention, and FIG. FIG. 1 is a diagram of one embodiment of a circuit. Note that in each case, one phase is shown.

In Figure 1, 1.3.5 is an AND circuit, 2.4 is a NOT circuit, 6 is an OR circuit, To, T+, T2,
T3 is an on-delay timer, and the self-ended breaker "cuts"
A transmitting circuit 8 is configured. 7 is an FM relay transmission circuit.

First, at the transmitting end, as shown in Fig. 1, the breaker trip command (3-phase OR signal) 52]χ and the breaker "off" signal!
When the AND condition with 12BX is established, an output is output to the AND circuit 1 (hereinafter, this state will be referred to as the "1" state). Next, after the on-delay timer To has expired, one side of the AND circuit 3 becomes "1". This on-delay timer To is the breaker trip command 521χ and the breaker [
This is for confirming that the cutting 11 item 52BX continues for a certain period of time or more. Here, the output of the on-delay timer T1 is not output (hereinafter this state is referred to as the "0" state), so the output of the NOT circuit 2 is "1", and the other input of the AND circuit 3 is also "1". Therefore, the output is rlJ
becomes. As a result, F)l at the transmitting end via the OR circuit 6
Level down signal 'JO of the transmission signal of current differential relay 7
The signal becomes "1".

Next, after the on-delay timer T1 expires, the outputs of 771 to circuit 2 become "0", and the output of AND circuit 3 becomes [0].
becomes. As a result, the level down control signal of the transmission signal of LH current difference -7 becomes rOJ.

Next, after the on-delay timer T2 has expired, one input of the AND circuit 5 is set to 11''. At this time, the output of the on-delay timer king 3 is "0", so the not circuit 4
The other human power of the AND circuit 5 is set to ``1J'' via .This sets the output of the AND circuit 5 to ``1'', so
Through the OR circuit 6, the level down control signal of the transmission signal of the H current differential relay 7 becomes "1".

Next, after the on-delay timer T3 expires, the
The output of ``84 becomes rOJ, and the output of AND circuit 5 becomes [
It becomes 0-1. As a result, the level down control signal of the transmission signal of the H current differential relay 7 becomes rOJ, and this
From step 7, the series of "level down 1 control of the transmission signal of the H current differential relay is completed. A time chart of the control at the transmission end is not shown in FIG.

Next, at the receiving end, the level-down signal of the transmission signal of the IH'ffi current differential relay at the transmitting end is transmitted to the disturbance detection circuit for the main channel of the FH current differential relay at the receiving end via the main channel of the H carrier. operates and detects that the breaker at the transmitting end is ``off''.

FIG. 2 is a block diagram of the receiving circuit 9 with the breaker at the other end turned off, including AND circuits 10.13.14.15.771 to 11.12, on-delay timers t1, t2, Otsu 3, and flip-flops. Circuit F/Fl, F/F2, F/
F3, “/”4 and auxiliary relay 1 for detecting breaker “off”
It consists of 6. Note that 17 is an "H relay receiving circuit.

Next, to explain the operation, at the receiving end, by controlling the level down at the transmitting end, the disturbance detection circuit for this channel of the current differential relay 7 at the receiving end operates, and the lock detection signal is activated. It is output and input to one side of the AND circuit. At this time, breaker trip command (3-phase OR signal)
If 52TX is output, the output of AND circuit 10 is 11.
becomes. This causes the on-delay timer C1 to start. The setting of this timer is 1〉. Here, the breaker trip command 52]x is used as a starting condition for both the transmitter end and the receiver 8 end, but this is because this circuit is used only during re-closing, and the circuit breaker trip command 52] The command 52[x is also used as a reset condition for this circuit. After the on-delay timer b expires, flip 7
071 circuit [/'1's cellar 1~The input of the side S becomes [1j, and its output Q is taken as '1'.

Next, by canceling the level town system t2++ at the transmitting end, the disturbance detection circuit for this channel of the [H current differential relay 7] at the receiving end returns to 1u, and the []tsuku detection signal becomes 1u.
Return and set the output of the 1-circuit 11 to [11]. Under the AND condition with the output of the flip circuit F/F1, the output of the AND circuit 14 becomes "1", and after the on-delay timer Otsu2 expires, the flip circuit F/[]
2's cellar 1 ~ side human power S roars "1", and its output Q is "
1". The setting of this timer is T2>a2-e.

Next, by controlling the level down again on the transmitting end side, the receiving end side [H current differential relay 7 for this channel]
The disturbance detection circuit operates and a lock detection signal is output), and one side of the AND circuit 15 is set to "1". At this time, the output Q of the flip-flop circuit F/2 is [11], so the output of the AND circuit 15 is "1".
becomes. Therefore, after the on-delay timer t3 expires,
Noritsubu-Norotsubu circuit F/"3 set side human power S"
1", and the output Q becomes "1". The setting of this timer is T3>3.

Next, by stopping the level down control at the transmitting end, the U disturbance detection circuit for this channel of the H current differential relay 7 at the receiving end is restored, the lock detection signal is restored, and the output from the NOT circuit 11 is restored. is set to "1". The output of the AND circuit 14 becomes "1" under the AND condition with the output of the clip-flop circuit F/F 1, and by setting the output to "1" after the time limit of the on-delay timer Otsu 2, the output of the AND circuit 13 becomes "1". All the input signals become "1" and the output is characterized by a flip-norotub circuit F/"
4], the side force S becomes ``1'' and its output becomes ['
11, the other party) 9-Nippon breaker [Auxiliary relay 7G for disconnection detection operates F1.

When the other end breaker ``off'' signal 8 receiving circuit returns, the outputs of the knob 1 to circuit 12 become ``1'' due to the return of the breaker 1 to the rip Ii command 52TX, and the flip-flop circuit ``
/"1, F/"2, F/F3, F/[4's reset side human power R is set to "1" to return its output to "0". FIG. 3 shows a time chart showing the operation of each circuit at the receiving end.

As can be seen from the time chart in Figure 3, in the embodiment of the present invention, the level of this channel is lowered twice, but if it is possible to distinguish it from a real disturbance occurring in this channel, how many times should this channel be leveled down? It is possible to downgrade the system as long as it does not change the gist of the invention. As described above, the A contact of the auxiliary relay 1G for detecting the "off" of the breaker at the other end is connected to the B contact 38, 39, 40 of the power flow detection relay of the system in the interconnection confirmation circuit with the other end shown in FIG. 6 for each set. By replacing it with , it becomes possible to check the interconnection with the other party ☆;'1: without installing a current detection relay (J).

``Results of the invention 1 onwards'' 2β1 As explained above, in the ``H current difference vJ relay system'' implementing the re-I circuit, the breaker of the mating terminal ``cut''
By lowering the level of this channel using the FH current differential relay of the other terminal, the condition is detected at the own terminal, and this is used to check the connection with the other terminal during re-closing.
The current detection relay used in the past is no longer required.

[Brief explanation of the drawing]

FIG. 1 is a self-terminal breaker "off" signal transmission circuit diagram of an embodiment applied to the H current differential relay system according to the present invention, and FIG.
The figure is a circuit diagram of a signal receiving circuit of a counterpart terminal breaker according to an embodiment of the present invention applied to an H current differential M electric system.
The figure is a time chart explaining the operation of the circuits in Figures 1 and 2, Figure 4 is a schematic diagram of a single-type FM current differential relay that transmits waveforms by FH transmission, and Figure 5 is a polyphase reclosing system. Fig. 6 is a detection circuit diagram when two or more healthy phases in total of two circuits are reclosed to the line ft, and Fig. 6 is a circuit diagram for confirming interconnection with a partner terminal. 1.3.5.10.13.14.15...AND circuit 2.4.11.12...NOT circuit 6.27^, 27B,...OR circuit 7...[H relay transmission Circuit 8... Self-end breaker "off" Transmission circuit 9... Other end p [i device "off" receiving circuit To, T
+, T2/T3, tl, t2, t3...On delay timer E/[1~E/'4...Flip-flop circuit 16
...Auxiliary relay 17 for detecting breaker at the other end "off"...
・H relay receiving circuit 22A, 22B...frequency conversion circuit 23A, 23
B... Differential current detection circuit 24A, 24B... Disturbance detection circuit for noise lock channel 25A, 25B... Constant frequency signal generator 26A,
26B... Disturbance detection circuit Fig. 3 Fig. 6

Claims (1)

[Claims] It transmits and receives the amount of electricity obtained at its own terminal and the other terminal via the transmission line, and detects an accident within the protected area based on the differential amount of each amount of electricity at its own terminal and the other terminal, and has a re-closing function. In the FM current differential relay method, which has the function of transmitting and receiving via the transmission line, the breaker at the other end for reclosing is set as the "off" condition to confirm the interconnection, and at the own end, the trip command signal and A transmission signal whose level is lowered by the AND condition with the breaker "off" signal is transmitted to the other end via the main channel of the FM carrier, and at the receiving end, it is received with the level lowered due to the presence of the trip command signal. On the condition that the time width of multiple received signals is within a predetermined time width,
An FM current differential relay system characterized by determining that the circuit breaker is "off."