SU1020905A1 - Device for single-shot auto-reclosing circuit breaker - Google Patents

Abstract

A DEVICE FOR A SINGLE AUTOMATIC REPEAT SWITCH OF A SWITCH containing a power supply unit with voltage stabilization, a charging resistor, an RC circuit, a short-circuiting voltage relay. a switch blocking contact and an executive relay, the output of which is connected to a switch control circuit, characterized in that, in order to increase safety and reliability of operation by simplifying the circuit and preventing repeated automatic switching on of the switch, the RC circuit connected in series, closes the 1st contact of the relay the voltage and the executive relay are shunted by the breaker blocking contact, the output of its executive relay is connected to the direct input of the operational control unit, realizing present the logical function memory, and the inverse input of the lazy-S councils actuator switch, is realized (A kvdego logic function prohibition forward input coupled to an output of the operational control unit. KD O O cl

Description

The invention relates to automation of power supply systems, and more specifically to devices for single automatic reclosing (CWD) of switches in underground power supply systems of mines and coal mines, dangerous due to the explosion of gas and dust. Condenser-type devices with start-up from block contacts and thyristors for single-reclosing are known. starters (contactor) after a brief temporary disappearance of the mains voltage tl} However, this device not only loses its contact with the breakdown of the Thyristor or the disconnection of the contactor block contact GUSTs once, but admits the samovklyuchenie actuator. Therefore, it cannot be used in underground networks where the use of automatic reclosing devices is allowed only once. The closest technical solution to the present invention is a device for a single automatic reclosure, comprising a power supply unit with voltage stabilization, a charging resistor, a discharge RC circuit, a closing contact of the voltage relay, a block contact switch, and an execution relay, the output of which is connected to circuit breaker control circuit 12 3. However, such a device also does not provide one-time action for 1 FU non-opening time "1 can and 1 block switch contact in the actuating relay circuit, which does not turn off, which leads to multiple m tnym action reclosing of the switch 1. A similar negative phenomenon occurs during diode breakdown. The purpose of the invention is to increase the safety and reliability of the operation of the circuit by simplifying it and preventing repeated automatic switching of the switch. The goal is achieved by the fact that the device containing a power supply unit with voltage stabilization charging resistor, a discharge RC circuit, a short-circuit voltage relay contact, a switch block contact and an executive relay whose output is connected to a switch control circuit are connected in series The C-circuit, for the “voltage” contact of the voltage relay and the executive relay, is shunted by the opening blocking contact of the switch, the output of its executive relay is connected to the direct input of the operational control unit, the implementation logical function of the memory, and with the inverse input of the drive control unit of the switch, which implements the logical function of the prohibition, the input of which is connected to the output of the operational control unit. FIG. 1 is a schematic diagram of a single-phase automatic re-on / off switch in FIG. 2 - a variant of the switch control unit; in fig. 3 is a variant of a relay contact circuit for control of a switch. The device contains a power supply unit with voltage stabilization, a high-resistance charging resistor 2, limiting the charging rate of capacitor 3, a discharge resistor 4, which with a capacitor 3 forms an RC circuit ((together with pin 5 of the relay voltage) safety time, the absence of voltage in the network, after which the automatic reclosing switch is prohibited, the actuator pej | e b, the auxiliary contact 7 of the switch,. terminals 8 and 9 for connecting saNfiJKauvdkh contacts of the service disconnect the action does not allow the automatic reclosing, switch control circuit 10, unit (relay) 11 of the operational control, switch actuator control unit 12, start button 13, button 14 Stop, contact 15 of the execution relay b, resistor 16, which provides the Hold circuit 11 after the signal is removed it is switched on and the contact 17 of the operational control unit 11. The device operates as follows: If the voltage in the network is of sufficient magnitude, the voltage relay (not shown), when activated, closes contact 5 (Fig. one). When the switch is turned on quickly (not shown), for example, using the Start button 13, the device 11 is triggered, the output of which gives a signal to turn on the switch drive control unit 12, and the latter is turned on. From the moment the switch is turned on (opening its block-contact 7), the capacitor 3 starts charging until the supply voltage 1 of the power supply is across the circuit: 2 - 3 - 5 - b, but the relay b does not work, because the current in its circuit is limited "Another resistor 2. The charging time of the capacitor is determined by the constant time value of the successive RC circuit 2-3. When the mains voltage disappears, the circuit breaker is disconnected by means of a voltage relay, the contact 5 of which is opened, and the auxiliary contact 7 of the switch P1 is closed. Capacitor 3 is charged at resistor 4. The constant discharge time of capacitor 3 to resistor 4 (up to the minimum relay operation voltage b) is determined by the safety conditions within a few minutes: for underground networks with a voltage 6 kV 3 min

for underground networks, the voltage is less than 1 kV for 1 min.

If the mains voltage is before the time set by the safety conditions, the voltage on the capacitor 3 is enough to operate. Relay B, KOTOi be triggered by the discharge current of the capacitor flowing through circuit 3-5 - 6 - 7 From the relay output 6 (FIG. 2), the signal is fed to the inverted input of the switch drive control unit 12 and the direct input of the operational control unit 11, which is its. After the voltage on the capacitor decreases to the release level of the relay 6, it turns off and the signal is removed from the inverse of the block 12 and the signal of the block 12 is triggered by the signal j supplied to its direct input from the block 11, the switch turns on and turns off. Pin 7 This completes the cycle of a single reclosure.

The automatic reclosing device works in the same way with relay-contact circuit (fig.Z)

After the relay has triggered, its contact 15 tayH tuts the Start button, the relay 11 "activates and is held in the ON state with current flowing through the resistor 16. After turning off) Chen1 {relay. 6 its contact 15 closes the power supply circuit of the control unit 12 || {water switch. The switch is closed as pin 17 of relay 11 is closed. If the network voltage is absent beyond; the time ,, set by the raBen dBBM RG-circuit 3-4, the switch is not turned on again, TsiK as condensate 3 is discharged to the resistor 4 to a voltage below the switching level of the relay 6. If immediately after turning on the switch, turn it off immediately from KJ "t ) 4eHHev, for example, as a result of operation, they are caused by short-circuit currents, LPV will not occur, because capacitor 3 will not have time to charge before the voltage is triggered by the relay 6. due to the presence of a high-resistance resistor to 2 in the charging circuit and a shortened time of no blo to-pin 7 switch.

In case of an on-line switch-off by means of a 14-stop button or by turning off the protection, after which the APV switch is disconnected, an amp and a 8.9 are connected for | "K1gi (1 pin contact of said buttons or a latch. A capacitor 3 is connected with these contacts). and the discharge current disappears successively, a need for switching on the relay b.

The one-time .APV with almost any failures of any element in the device circuit is provided as follows.

If the auxiliary contact 7 of the switch fails, when it does not switch and remains closed in the on state, the capacitor 3 does not charge, because its charging circuit is shorted by the indicated contact. Consequently, when the switch is disconnected, there is no discharge current, which is not needed to turn on the executive relay 6.

On failure, when the auxiliary contact 7 remains open regardless of the state of its switch, although there is a charge circuit of capacitor 3, but there is no circuit of its discharge, therefore when the switch is turned off, relay 6 does not operate. During the breakdown of capacitor 3 (short circuit between the plates), the relay 6 switches on even at time BKJB04eHHoro the switch state when the auxiliary contact 7 is open, because the current in its circuit is limited by the resistance of the high resistor 2.

Thus, with all possible failures of elements in the circuit of the proposed device, multiple automatic reclosing switches are excluded.

One-time reclosure is also provided in case of failures of the executive relay 6 V. In case of failure of relay b, when it does not work, the signal from its output does not enter the input of the operational control unit 11 (Fig. 2 and 3) and it does not work, therefore it does not work and an actuator 12 for drive etching.

In case of failure, when the relay remains permanently on, the signal from the output of this relay enters 11 (Fig. 2 AC output and the last receives a signal at the direct input of block 12, implements the ZARIPET function, but it does not work, because its inverse input also receives a signal from the output of relay b,

The prelaggered device retains the property of a one-time ALV and when it interacts with the relay-contact circuit 10 of the switch control (Fig. 3) ..

If relay 6 fails when it does not work, its closed contact 15, shunt button 13 Start, open, relay 11 does not work, because the current in its winding is limited by the resistance of resistor 16,

In case of failure, when the relay 6 remains permanently switched on, its pin 15 switches on the relay 11 and raises the power supply circuit of the switch actuator control unit 12.

Thus, for any failures, an executive automatic reclosure does not occur,

The use of the proposed device prevents the repeated reclosing of the switch for a short time.

short circuit at possible failures in the circuit and thereby exclude temporary lesion of the flange explosion protection of the switch shell and, consequently, transfer of the explosion of methane-air mixture from the shell to the underground mine workings and increase its functionality by reducing the number of elements directly in the AR circuit.

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Claims (3)

DEVICE FOR ONE-TIME AUTOMATIC REPEATED CIRCUIT BREAKING OF THE CIRCUIT BREAKER, comprising a power supply unit with voltage stabilization, a charging resistor, a discharge RC circuit, a closing contact of a voltage relay, a contact block of a circuit breaker and an executive relay, the output of which is connected to the control circuit of the circuit breaker, which differs in that , in order to increase the safety and reliability of operation by simplifying the circuit and preventing repeated automatic switching on of the circuit breaker, the RC-circuit connected in series, closing The first contact of the voltage relay and the executive relay are bridged by the disconnecting block contact of the switch, the output of its executive relay is connected to the direct input of the operational control unit that implements the logical memory function, and to the inverse input of the control unit of the drive of the switch that implements the logic inhibit function, the direct input of which is connected to the output operational control unit house. f „„ SU ,,,, 1020905 I " In FIG. 1 is a schematic diagram of a device for a single automatic repeated switching of a circuit breaker; in FIG. 2 - version of the control unit of the switch; in FIG. 3 is a variant of the relay contact circuit management circuit breaker. The device comprises a power supply unit 1 with voltage stabilization, a high-resistance charging resistor 2, limiting the charging speed of the capacitor 3, a discharge resistor 4, which with the capacitor 3 forms an RC circuit, fixing together with the voltage relay contact 5 the time of the absence of voltage in the network, set by the safety conditions, after which is prohibited by the automatic reclosure of the circuit breaker, executive mode b, block contact 7 of the circuit breaker. .