RU2542754C1 - Control method of trip failure of network station switch of automatic load transfer at restoration of normal electric power supply circuit of ring network - Google Patents

Abstract

FIELD: electricity.

SUBSTANCE: since voltage supply to the line of the main power supply source a countdown is started, and it is equal to delay time for tripping of network station switch of automatic load transfer. In the line of the main power supply source increase of operating current is monitored, while in the line of the reserve power supply source its decrease is monitored, and these values are defined by reserved load in the line of the main power supply source; when it does not occur then conclusion is made about trip failure of network station switch of automatic load transfer at restoration of normal operation of the ring network.

EFFECT: enlarging functional capabilities of the method.

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Description

The invention relates to the automation of electrical networks and is intended to control the failure of the circuit breaker circuit breaker point automatic turn-on reserve (ATS) when restoring the normal operation of the ring network.

There is a method of monitoring the failure of disconnecting an ABP point when the circuit breaker is turned on for a stable short circuit (short circuit), which consists in the fact that from the moment of the inrush of a short circuit on the transformer buses of the main power source, a time equal to the shutdown time of the operation of the ABP network point plus the protection response time is counted its circuit breaker. At the same time, the occurrence of a fault inrush current on the tires of the backup power supply is controlled and if it appears after turning on the switch of the ATS point, and at the end of the countdown of the total time, the inrush of a short-circuit current does not occur, then the fact of failure of disconnecting the ATS point when its circuit breaker is turned on for a stable fault is established in the ring network [patent RU No. 2304339 C1, cl. H02J 13/00, publ. 08/10/2007, bull. No. 22].

The disadvantage of this method is the impossibility of using it to control failure to turn off the circuit breaker of the ABP network item when restoring the normal operation of the ring network.

The objective of the invention is to expand the functionality of the method by obtaining information about the failure to turn off the circuit breaker of the network item ABP when restoring the normal circuit of the ring network.

According to the proposed method, from the moment of supplying voltage to the line of the main power source, a countdown starts, equal to the shutdown time of the circuit breaker of the ABP network item, while the increase in the line of the main power source is controlled, and the operating current is reduced by the same value, determined by the reserved load of the main power supply line, and if this does not happen, then a conclusion is made about the failure of disconnecting the ABP network point when restoring the normal circuit ring network bots.

The essence of the invention is illustrated by drawings, where:

- figure 1 presents a structural diagram containing elements for implementing the method;

- in Fig.2 - diagrams of signals at the terminals of the elements shown in Fig. one.

The circuit (see figure 1) contains power transformers 1 and 9; input switches 2 and 10; head switches 3 and 7; sectional switches 4 and 6; switch 5 network point ABP; sectional switch 8; the sensor increases the working current (DVRT) 11; voltage sensor (DN) 12. Elements: MEMORY 13; NOT 14; DELAY 15; SINGLE-VIBRATOR 16; sensor for decreasing the operating current (DURT) 17; element NOT 18; element And 19; recording devices (RU) 20.

The signal diagram at the outputs of the elements shown in figure 1 (see figure 1), has the form (see figure 2): 21 - at the output of element 11; 22 - at the output of element 12; 23 - at the output of element 13; 24 - at the output of element 14; 25 - at the output of element 15; 26 - at the output of element 16; 27 - at the output of element 17; 28 - at the output element 18; 29 - at the output of element 19; 30 - in RU 20.

In addition to the diagrams of the output signals, FIG. 2 also shows: t ₁ is the instant of occurrence of voltage in the line of the main power source; t ₂ - time of tripping of circuit breaker 5 of the network item ABP.

The method is as follows.

In the normal mode of operation of the ring network, switches 2, 3, 4, 6, 7 and 10 are turned on, and switches 5 and 8 are turned off. If the voltage disappears on the buses of the main power source, for example, when the protection is tripped and the switch 2 is turned off, then the switch 3 is turned off and the switch 5 is turned on, the circuit will provide power to all consumers of the main power supply line from the backup power source of the transformer 9. In this case, there is no voltage on the main buses the power source ensures the absence of a signal at the output of DN 12 (figure 2, diagram 22), therefore, the circuit is in control mode.

After troubleshooting and turning on the switch 2 will automatically turn on the switch 3. The appearance of voltage on the tires of the main power source will lead to the appearance of the output signal on DP 12 (figure 2, diagram 22, time t ₁ ). This signal will be received at the input of the MEMORY 13 element, it will be remembered by it (Fig. 2, Diagram 23) and will be received at the input of the DELAY 15 element. From the output of this element, the signal will appear after the shutdown time of the off switch 5 of the ABP network item (Fig. 2, Diagram. 25) and will go to the input of the Single Vibrator element 16. It will produce one oscillation (Fig. 2, Diagram 26), this signal will "erase" the memory from element 13 (Fig. 2, Diagram 23) and will be received at the input of the And 19 element. With proper automatic operation means to this point in time (t ₂₎ must disconnect switch 5, but for some reason Lieb malfunction, it will not turn off and at the outputs of the DVRT 11 and DURT 17 the signals will not appear (Fig. 2, Diagram 21 and 27), therefore, there will be signals on the outputs of the elements NOT 14 and NOT 18 (Fig. 2, Diagram 24 and 28), which will ensure the operation of the element And 19 (figure 2, Fig. 29). This signal, having arrived at RU 20, will provide information in it that the switch 5 of the ABP network point has not tripped.

Thus, the proposed method allows to obtain information about the failure of disconnecting the circuit breaker of the network point of automatic inclusion of the reserve when restoring the normal operation of the ring network.

Claims (1)

A method for monitoring the failure of opening the circuit breaker of the automatic transfer switch (ATS) network point when restoring the normal circuit of the ring network, which consists in fixing the inrush currents and in measuring the time between them, DIFFERENT in that, from the moment of supplying voltage to the main power supply line, the time starts counting, equal to the shutdown delay time of the circuit breaker of the ABP network item, while the increase is controlled in the line of the main power supply, and the ie - a decrease in the operating current, determined by the reserved load of the line of the main power source, and if this does not happen, then a conclusion is made about the failure to turn off the circuit breaker of the ABP network item when restoring the normal operation of the ring network.

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