JPS58139629A - Ground-fault relay - 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] This invention relates to a ground fault relay.

Generally, when performing earth fault protection for each section of the same electrical circuit, 11 earth fault force relays are installed in each section,
Set the operating time of the earth fault force relay in the higher level section (power supply@) so that it is longer than that of the lower section (9 loads@) to achieve time coordination, and limit the interrupted section. That's what I do. However, the operating time of the ground-joint directional switch at the power company's substation is generally set at about 0.4 to 0.5 seconds (although it varies depending on the 11 locations).

Therefore, the operating time of the top-level directional relay in Yushanjaku must be set to 05 seconds or less, and an earth fault directional relay is installed in the casque V in Yushanjaku to ensure ground faults. The limit for doing this is up to 3 dans. However, recent 1llll
In many cases, I* requires 4 or more stages of Fi, making it difficult to coordinate ground fault protection theory.

The present invention is based on the above-mentioned points, and even when four or more underground electrical appliances are installed in a cascade within each demand, coordination can be achieved easily and reliably, and power outage sections can be minimized! ! - Intended to provide relays.

DESCRIPTION OF THE PREFERRED EMBODIMENTS A ground fault directional relay according to one embodiment of the present invention will be described below with reference to the drawings. In FIG. 1, interruptions 1i1.5, 8. Zero-phase t#l device 2.6.9. The ground fault direction relays 3, 7.10 are arranged in a cascade PKI device in one electrical path, and each of the ms direction relays 3, 7.10 is constructed as shown in FIG. Terminal 2! , 22, the zero-sequence current output from each of the zero-sequence current transformers 2.6.9 is added to the input t
fIt device 41, over-input protection circuit 42, zero-phase Ti setting circuit 43 s7 (LED (light emitting diode) 48 is driven by the router circuit 44, full-wave rectification circuit 45, smoothing circuit 46, and level detection circuit 47) , this LED 4g lights up when the zero-sequence current is equal to or higher than the set level.The zero-sequence voltage output from the zero-sequence voltage detection device 4 (see Figure 1) is applied to the terminals 23 and 24, and the The Lgnso is sent through the maintenance circuit 8'' 51, the zero-phase voltage setting circuit 52, the filter circuit 53, the full-wave rectifier circuit 57, the smoothing circuit 58, and the level detection circuit 59, and the zero-phase voltage of level 9 or higher is detected. In addition, the output of the filter circuit 44 is sent to the phase discrimination circuit 56 via the waveform shaping circuit 49, and the output of the filter circuit 53 is sent to the phase discrimination circuit 56 via the waveform shaping circuit 54 and the phase setting circuit 55. It is determined by 4'tl whether the phase of the zero-phase output is within the settled phase.Level detection 1 circuit 47
．． 59 and the outputs of the phase discrimination circuit 56 are connected to an AND circuit 61.
When the respective outputs are aligned, that is, when the zero-phase 11 current and voltage levels are each higher than the setting level and the phase is within the setting phase, a ground fault detection signal is generated from this AND circuit 61. This ground fault detection signal is sent to the time setting circuit 62 via the AND circuit 71, and the time setting circuit 62 generates an output in response to this time elapsed time when the ground fault detection signal continues to be generated for the time that the ground fault detection signal has settled. LED6 via output circuit 63
When 4 is driven, the KIJ relay is driven and the normally open contact 66 closes and the normally closed terminals 27 to 30 open *A67.
The trip signal 13 is sent to the IT device 1.5.8 through
is sent and an interrupt operation is performed. In addition, terminal 25.2
A power transformer @ (not shown) is connected to 6, and power is supplied to each (b) path via a transformer 81, an over-input protection circuit 82, 1m circuit 83, 111 circuit 84. ing. The push-button switch 85 is for testing.The configuration of 0 or more is the configuration of a normal earth fault direction relay and PlIl, except for the ANDl# path 71.

According to the present invention, AND (c) path 71. Instantaneous operation circuit 72
, the output circuit 73, the relay 74, the operation inhibit circuit 76, the inverting circuit 77, and the relay 74 are photographed as being normally open. The ground fault detection signal output from the ANDI circuit 61 is sent to an AND-path 71 and also to an instantaneous operation circuit 72, and an output is instantaneously generated from this instantaneous operation circuit 72 and drives a relay 74 via an output circuit 73. , the WjA contact 75 is always closed.

Terminal 31.32tl has the same configuration as the terminal 33.34Kii class of other ground fault directional relays above, and our TO 1
When the contact 75 closes, an operation stop signal 11 (see gil 1 diagram) is sent to the operation prohibition circuit 76 of the upper earth fault direction relay. When the operation prohibition circuit 76 does not receive the operation prohibition signal, it produces an output of "0" and sends an output of "1" to the AND circuit 71 through the inversion circuit 77. Therefore, an output is generated from the vkK time setting circuit 62 at 9-9 hours when the operation prohibition signal is not received from the lower order, and an interrupter trip signal is output, but when the operation prohibition signal is received from the lower order, the inversion circuit 77 outputs an output. Ninth AND circuit 71Fi where becomes "0"
Transfer of the ground fault detection signal to the time setting circuit 62 is immediately stopped.

Therefore, the time setting circuit 62 suspends its operation and remains at fc, and generation of the trip signal is prohibited.

The input is given to the time setting circuit 62 of each kII'i of Nos. 3 and 7.10 to start timed operation, but at the same time as this start, the operation stop signal 11 is instantaneously directed to the upper ground - all electric appliances. and send. That nineilI! The operation of the time setting circuit 62 is stopped by the operation inhibit signal 11 from the device 7.10.

The output of the tap signal 13 is prohibited. As a result, only the lowest W# device 8 closest to the fault point 12 is tripped and the power line is interrupted, thereby making it possible to limit the power outage section.

As explained above, if a ground fault relay with a single source of 1J1K is used, even when installing a multi-stage cascade P, it is possible to enjoy safety coordination and ensure safety, and to minimize damage caused by ground fault accidents. You can find the strength to stop it.

In addition, Kamiyu's explanation was given regarding one embodiment of the Kojibako directional relay, but the earth fault relay 1 [which does not have directionality] also has the same
Of course, it can be used in K. −

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a round system in which a mackerel direction joint device is installed according to an embodiment of the present invention, and FIG. 2 is a diagram showing the configuration of the same embodiment. 1.5.8... Interrupter 2.6.9... Zero-phase current transformer 3.7.10-... Earth fault directional joint 11 protection 4... Zero-phase voltage detection device 141...・Input current transformer 42
．． 51.82... Over-input protection circuit 43... Zero phase *R
Setting circuit 44.53...Filter circuit 45.57...Full wave rectifier circuit 46, 58...Smoothing circuit 47.59...Level detection circuit 48, 6 Q, 64・L B D49.54・
・Waveform shaping circuit,

Claims (1)

[Claims] (1) #jtl that detects a tangled fist error and generates a detection signal!
M detection circuit; a time setting circuit that produces an output when the detection signal is continuously input for a predetermined time; and an interrupter trip signal is output in response to the output of the time setting circuit. In a ground fault electrical appliance, the circuit includes an instantaneous operation circuit that instantaneously generates an output in response to the detection signal, and an operation prohibition signal output circuit that sends an operation prohibition signal to another ground fault relay by the output of this temporary operation circuit. and a prohibition circuit that receives an operation prohibition signal sent from another ground fault relay, stops the operation of the time setting circuit, and prohibits the output of the rip signal (interrupter). Earth fault joint 1 [&.