SU1651334A1 - Device for protection when switching in transmission line - Google Patents

Abstract

The invention relates to electrical engineering, in particular to relay protection of power systems. The purpose of the invention is to increase speed and increase the sensitivity of power line protection without detour when it is turned on. The goal is achieved in that the emergency component of the power line current is compared with the emergency component of the electrical model of the protected line. 1 il.

Description

The invention relates to electrical engineering, in particular to relay protection of power lines.

The purpose of the invention is to increase speed and increase the sensitivity of power line protection without detour when it is turned on.

The drawing shows a block diagram of the proposed device.

A voltage transformer 1 is connected to the input of an electric model 2, consisting of a power transmission line model 2.1 and a node model of the opposite side of line 2.2; the current transformer 3 is connected to the emergency components filter (FAS) 4, the output of which is connected to the inverting input of the adder 5, to the second non-inverting input of which the current components filter (FAS) 6 is connected at the beginning of the electrical model of the line; the output of the adder 5 is connected to the amplifier-limiter 7, the output of which in turn is connected to the first input of the element 8. 8. The output of the one-vibrator 9 is connected to the second input of the element 8, and the output of the element 8 connects to the actuator 10, which turns off the switch. Trailing

The relay contacts of the switch block contacts 11 are connected to the input of the one-shot 9 at this end of the line, and are connected to the transfer unit 12 at the opposite end. The closing contact of the output relay 13 of the switch-on fixing device 14 on the opposite side of the transmission line 2.2 and line model block 2.1.

The device works as follows.

When the switch is turned on, the secondary voltage of the line voltage transformer is fed to the input of the electric model 2, and simultaneously from the closing relay repeaters 11

a block-contact switch operates a one-shot 9 at the time of putting this protection into operation. The output voltage of the model, identical to the current in the line, at the same time point is converted into the FAS of the current 4 and falls into the adder 5, where the signals of the emergency components of the model and the real line are compared. In the absence of damage to the power lines at the output of the adder, there is no signal. In the case of a KZ. or other (L

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Damage the adder signal is amplified in the limit amplifier 7 and tilts the element AND 8, because the signal of the one-shot 9 arrives at its second input. Element I 8, having triggered, gives impulse to the executive body 10 to switch off the damaged phase. A change in the working conditions of the opposite end of the line is fixed by the repeaters 11 of the switch block contacts and using a communication channel consisting of the transmission unit 12 and the closing contacts of the output relays 13 of the reception unit 14, the corresponding model of the node is made.

 The use of this device in conjunction with other devices of relay protection of the line will significantly increase their speed, about 10-100 times, because transient and sensitivity are monitored if the line is damaged during switching on without the use of expensive high-voltage switches with upstream resistances.

The positive effect from the use of this device will also be expressed in the reduction of the time of switching off the KZ. and, therefore, in increasing the dynamic stability of the system.

Claims (1)

Claims An apparatus for protecting a transmission line when it is turned on, comprising current transformers and line voltages, an electrical model of the line including the line model block, and the node model block at its opposite end, the adder and the executive body, characterized in that, in order to increase speed and increase the sensitivity of the power line protection without bypassing when it is turned on, the device additionally introduces a filter for the emergency components of the current line, a filter for emergency components for the line model, a one-shot, amplifier-limiter and an element And an emergency filter input is connected to the output current transformer components of the current line, the output of which is connected to the inverting input of the adder, the output of which through the amplifier - limiter is connected to the first input of the element I, the output of which is connected to the input of the executive body, to the output of the line voltage transformer the first input of the line model block is connected, the output of the electric line model is connected through the emergency components filter of the line model to the direct input of the adder, the one-shot input it is intended to be connected to the closing contact of the relay of the repeater of the circuit breaker contacts at this end of the line, and its output is connected to the second input of the element I, the second input of the block of the line model and the input of the node model at its opposite end is intended to be connected to the closing contact of the output relay of the latching receiving block of the on position of the switch.