SU1654909A1 - Device for overcurrent protection of electrical plant having two taped bus systems - Google Patents

Abstract

The invention relates to electrical engineering and can be used as current protection for protecting 6-10 kV substations with two bus sections. The purpose of the invention is to increase the speed of protection without disturbing the selectivity in the event of damage to the tire section adjacent to the feed gland. The goal is achieved by blocking the output of the device to disconnect the power input from the overcurrent unit, which detects the flow of current through the section switch. 2 Il. (L

Description

This invention relates to relay protection of power supply elements.

The purpose of the invention is to increase the speed of protection without disturbing the selectivity in a two-compartment pre-device in the mode with a sectional switch on.

FIG. 1 shows the power input protection circuit; in fig. 2 - protection circuit breaker.

The device contains contacts 1-3 of the current input power relay, relay 4 time with contact 5, output relay 6 for protection of the input input, for example RP-23, with contacts 7-9, contacts 10-12 current relays of the sectional switch, relay 13 for starting protection sectional switch with deceleration m to drop, for example RP-252, with closing contact 14 and disconnecting contact 15, output relay 16 of protection of a sectional switch, for example RP-23, with closing contact 17 and disconnecting contact 18.

In the normal mode, contacts 1-3 and 10-12 of the current relay are open, there is no voltage on relays 4, 6, 13 and 16.

In case of a short circuit on the sections supplied by the input, any of the contacts 1-3 (Fig. 1) closes, the time relay 4 is activated and after a set time the input protection output relay 6, which contacts 7 through the contacts 15 of the provided relay 13 gives a pulse to turn off input.

When a short circuit to another section closes any of the contacts

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1-3 and any of the pins 10-12. When the contacts 1-3 are closed, the relay 4 is activated, and after a set time of the relay 6. When the contacts 10-12 are closed, the relay 13 is triggered (FIG. 2) and, after the relay 6 is activated and the contacts 8 or 9 are closed, the relay 16, which contacts 17 gives an impulse to disconnect the sectional switch Before the sectional switch is turned off, the input protection is blocked by contacts 15. The sectional switch can be switched off by protecting any input (pins 8 and 9). If the sectional switch is successfully disconnected, the circuit returns to its original position.

If a sectional switch fails, the relay circuit 13 is broken by the contacts 18 of the activated relay 16. When the relay 13 disappears, the input protection is unlocked and is activated. The time delay for the falling out of the relay 13 makes it possible to rebuild from the time the sectional switch is turned off.

If a protection switch has a sectional switch, the position is on, the relay 16 may not be installed and the circuit of the relay 13 is broken by the closing contacts of the positioned On switch. The circuit for disconnecting the section switch in this case is assembled by pins 14 and 8 (or 9).

The use of the proposed protection device makes it possible, without additional costs, to reduce the time delays on the power inputs and to increase the reliability of the power supply circuit.

Claims (1)

Invention Formula A device for current protection of electrical installations with two partitioned bus systems containing a current supply input, one terminals of the closing contacts of which are combined and connected to the first pole of the operating current power source, the other outputs of these contacts are also integrated and connected to the second pole of the operating current source, between the poles of which are included the successively connected closing contact of the time relay with deceleration to actuation output winding five 0 five 0 five five 0 5 supply input relay, one output of the first closing contact of the latter is connected to the first pole of the operating current source, the current relay of the sectional switch, one terminals of the closing contacts of which are combined and connected to the first pole of the operational current source, other conclusions of the closing contacts are also combined; a switch with deceleration for drop-off, the first winding terminal of which is connected to the second pole of the operating current source, the first terminal of the closing contact of the decree This relay is connected to the first pole of the operating current source, the output relay of the sectional switch, the first winding terminal of which is connected to the second pole of the operational current source, one output of the closing contact of the output relay of the sectional switch, the other terminal is intended for connection to the circuit disconnecting a sectional switch, characterized in that, in order to increase the speed of protection without disturbing the selectivity in the case of damage to a section of tires, I adjoin the second and third closing contacts of the output relay of the input input, the opening contact of the output relay of the sectional switch and the closing contact of the latching relay of the protection protection of the sectional switch with short-circuit to actuation, the first output of the latter is connected to another output of the first output contact supply input relay, the second output of the specified contact is intended to be connected to the disconnecting circuit of the supply input switch, the disconnecting contact of the output relay with The section switch is connected between the second combined outputs of the current relay sectional switch and the second output winding relay of the protection start of the section switch with 337 slower drops, between the second output contact terminal and the second output terminal of the section switch are connected in parallel to the second and third output contacts power input relay. / 2 5b 7/6) 15 (13} Nahtm. figure 1 FIG. 2