SU120240A1 - Self-assembling from high voltage distribution network - Google Patents

Description

The proposed self-assembling high-voltage distribution network line refers to a well-known type of such two-way power lines and installed at the beginning and end of the circuit breakers equipped with relay protection and automatic recloser circuit breakers.

Similarly to the known self-assembling lines, along the proposed line there are network transformer points equipped with two load switches, controlled by a relay circuit, powered by two voltage transformers connected on both sides of the transformer point.

Known self-assembling lines allow automation of a large number of transformer points, however, after an emergency shutdown, they are powered through fuses, which can limit the number of transformer points included in the line for automation. After the automatic shutdown of the damaged section, the line is self-assembled, but requires it to be brought back to normal by a series of switchings by the duty attendant at each transformer station.

The peculiarity of the proposed self-assembling line, which makes it possible to reduce the installed equipment, is to connect a network transformer between series-connected load switches equipped with one common drive, one of the switches being fused by fuses.

FIG. 1 shows a line diagram in a normal position; in fig. 2-diagram of the line after switching off the short circuit with oil switches of the supplying substations; in fig. 3-line diagram according to number 120240-2 -

barely self-collecting; in fig. 4-scheme of automation and secondary circuits of one transformer point.

Oil switches 1 and 2 on. the supply substations are equipped with automatic reclosing automatics.

Each automated transformer center of the TP is equipped with two load switches, of which switch 4 is shunted by a fuse 5. The load switches are equipped with a common drive controlled by a relay circuit (Fig. 4). Switches 3 and 4 loads are normally connected in series to the distribution network. From the intermediate bus between the switches 3 and 4, the power transformer 7 is supplied through the fuse 6.

If the cable is damaged at point K (Fig. 2), the short-circuit current triggers the maximum protection and switches off the switches / and 2 at substations A and B. After the voltage on the line disappears from the action of the low-voltage relay with time delay, the drives of the switches 3 operate and 4 loads.

On all TPs, simultaneously with the disconnection of both switches 3 and 4, the actuator springs are turned on (Fig. 2).

Then, under the action of the ARC, the switches / and .2 are closed, voltage is applied to the line from substations A and B, as a result of which the circuit line starts to recover from the damaged section to the damaged section.

On the side of the substation L, TP-1 receives a voltage of a voltage transformer 8 and switch 3 is turned on. Since a short circuit has occurred at TP-3, a voltage transformer 9 also receives power and a switch 4 is closed. The fa returns to its normal position. Similar actions of automation will occur at TP-2.

At TP-3, after supplying voltage to the voltage transformer 8, switch 3 is turned on. Since there is a short circuit directly behind this TP-3, fuse 5 will blow and the voltage transformer 9 will not receive power. Consequently, the further operation of the automatics stops and the switch 4 remains off.

As a result, the power transformer 7 at TP-3 will normally be powered from substation A. The damaged section of the line from the TP-3 side will be disconnected.

The restoration of the circuit from the substation B is as follows.

Under the action of AR, the switch 2 at the substation B closes and the voltage is applied to the transformer 9 of TP-6 voltage, and the power transformer 7 is supplied through the fuse 5. The switch 3 closes and, as the short circuit is behind the TP-4, the power supply circuit is restored. TP-5. Upon receipt of power, switch 3 is closed at TP-4.

Since this switch will turn on for a short circuit, the bypass fuse 5 will blow and TP-4 will be disconnected if there is voltage on its voltage transformer 9. After that, the automatic switch in TP-4 switches off 3, and switch 4 turns on Thus, the entire scheme will take the form shown in FIG. 3, i.e., after activating the AR and self-healing of the line, the damaged area is turned off.

FIG. 4 shows the scheme of automation and secondary switching at the transformer point TP-1 of the line under consideration at the moment

when the line section was de-energized when the line section was damaged, the switches / and 5 and substations A and B and the load drives tripped, i.e. the 3 n 4 switches were turned off and their switching springs were started.

When the circuit breaker I closes, the action of the automatic reclosing at the substation A receives the voltage of the voltage transformer 8 and supplies it from the low voltage side to the relay 10, which pushes the // // 12 contacts, and to the switching coil 13, which has a delay of sec. The coil 13 is activated and under the action of the actuated spring, the switch 3 is closed and the auxiliary contacts 14-75, 16-17, 18-19, 20-21 are opened. The power transformer 7 gets threading and through the fuse 5 also a voltage transformer 9 and a line in the direction of the transformer station TP-2.

From the voltage transformer 9, the energizing coil 22 is supplied through the contacts 11-12 of the relay 10 and the auxiliary contacts 23-24. Coil 22 has a time delay of 0.5 seconds.

At the same time, the voltage is supplied to the electric motor 25 of the drive 26, which begins to operate and start the load 27. Through the contacts 28-29 of the electric motor 25, a relay 30 is turned on, which closes the contacts in the circuit of the low-voltage relay 31 with time delay. After 0.5 seconds. the coil 22 is triggered and the iodine closes the switch 4 with the action of the actuated spring, and the circuit in TP-1 is restored.

The blocking contacts 32-33, 23-24, 34-35 on the shaft of the switch 4 are opened, and the contacts 36-37 are closed. 10 n 3 relays remain on.

At the transformer point TP-2 and other actions of automation will be similar.

After receiving power by the voltage transformer 8 at TP-3 and closing the switch 3, the line behind TP-3 turns on for a short circuit, as a result of which fuse 5 does not regen to voltage transformer 9 does not receive power.

The turn-on coil 22, without receiving power, does not operate and the switch 4 remains disconnected, and the damaged cable on the side of TP-3 will be isolated. The operation of the circuit when it is restored is 1n1 and from the side of the substation A is over.

The restoration of the circuit from the substation B begins independently of the substation A by switching on the automatic reclosing switch 2.

After that, the voltage transformer 9 at TP-6 supplies the voltage through the block contacts 32-33 on the shaft of the switch 4 to the coil 38, which in 1 sec. switch 3 is activated and turns on, as a result of which power is supplied to the transformer of voltage 8 and to the line in the direction of ТП-5.

The voltage transformer 8 energizes the relay 10, which closes contacts 11-12, as a result of which a circuit is created and through; 0.5 seconds the switch 4 is turned on with the help of the coil 22, and the circuit at this transformer point will be restored. The motor 25 is turned on and is working to lift the load.

At TP-5, the action of automation is similar to its effect on TP-6.

Subject invention

Self-assembling from the high-voltage distribution network, with two-way power supply and installed at the beginning and end of its switches, equipped with relay protection and automatic reclosing, with network transformer points located along it,

№ 120240

No. 120240-4 -

equipped with two load switches, controlled by a relay circuit consisting of a minimum voltage relay and three intermediate relays powered by two voltage transformers connected on both sides of the transformer center, which, in order to reduce the installed equipment, the network transformer is connected between a series of load switches equipped with one common drive, one of the switches being connected by fuses.