SU1617518A1 - Method of automatic reconnection of breakers of high-voltage connections - Google Patents

Abstract

The invention relates to electrical networks with a voltage of 6 to 35 kV and can be used to control the automatic reclosing (AR) of switches in these networks. The purpose of the invention is to increase the reliability and reliability of the diagnosis of emergency shutdowns of switches. When fixing the relay protection of the first inrush current short circuit. the first cycle of a double reclosure is performed in the time interval T ₃ - T ₄ , the cycle of a single reclosure - T ₅ - T ₆ , the duplicate command of the first crate of the automatic reclosure is given in the interval T ₇ - T ₈ , the second fold of the reclosure - in the interval T ₉ - T ₁₀ , the duplicate command of the second battery of the automatic reclosure is in the interval T ₁₁ - T ₁₂ . At the same time, T ₃ -T ₄ Τ ₅ -T ₆ Τ ₇ -T _{8 9} -T ₁₀ Τ ₁₁ -T ₁₂ . 2 Il.

Description

The invention relates to the field of electrical networks with a voltage of 6- 35 kV and can be used to control the automatic re-opening of switches in these networks.

The aim of the invention is to increase the reliability and reliability of diagnosing emergency shutdown of accessory switches.

In Fig. 1, diagram of inrush of short-circuit current in a monitored network with single (a) and double (8) automatic reclosing of the switches is iso-reflected; figure 2 - structural diagram of the device AI1B that implements this method.

The method consists in the following.

If at time t (Fig. 1) a short circuit has occurred, which

If the relay protection was at the moment of time t, then the break cycle of the switching on of the double-switched switches should be made in the time interval tj-t, and the switches that are turned on once in an integral time. In the event of a failure of the first battery of the LPV, a duplicate switch-on command is given in the timeframe. ,, - t:, 2. Duration of time intervals t3-t4, tj-t6, tT-tg,, o, t ,, - t, 2

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Determined by the number of switches in the monitored network and the accuracy of setting and controlling the time of AR, Time duration, tg-ty, tg-t ,, t, 5-t is determined by the degree of selectivity of time interval control using the system for obtaining information on the results of automatic re switching on the switches in the controlled network according to the duration of the pauses between inrush of the short circuit current.

A device that implements the proposed method (FIG. 2) contains a power supply unit 1, a transducer 2 rectangular pulses, which transforms an alternating voltage at its input into rectangular pulses, elements 3 and 4 times, which with the help of pulse counters carry out the counting pulses delivered by converter 2. The control inputs of the time elements are connected to the auxiliary contacts 5 of the high voltage switch 6. The output circuits of the time element 3 are connected to the control inputs of the memory elements 7 and 8, the working inputs of which th associated with access time of the element A, and outputs via the OR gate 9 and the actuator 10 connected to the actuator 11 of the switch 6. The time element 4 is formed with two outputs, the first of which has a number of settings for more than the number of time-controlled network switches.

Time element 4 contains elements 12 and 13 for setting the set time parameters for the first and second reclose cycles, respectively, the input circuits of which are connected to the outputs of the pulse counter 14, and the output circuits are connected to the first inputs of the OR elements 15 and 16, the second inputs of which are connected to a duplicate ( their counter outputs.

The device works as follows.

The voltage from the monitored line is supplied to the power supply unit 1, which supplies the direct voltage to the circuit elements and the alternating current voltage to the converter 2, which produces an impulse1) Square wave with a frequency of 50 Hz to the counting inputs of the counters 3 and 4 of time. When the high-voltage switch 6 11hol, its in the included

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The position, on the control input of the counter 14, is given a prohibitory signal, resetting the readings and prohibiting the counter. A control signal is fed to the control input of the time element 3, at which the counter continuously counts pulses. After the time interval corresponding to the preparation time for reclosing expires, the signal from the output of time element 3 is applied to the control inputs of memory elements 7 and 8 and puts the latter into a working state where the signal at the working input causes a signal at the memory element output .

In case of emergency shutdown of the switch 6, a prohibitory signal is fed to the control input of the time element 3, which returns the counter to its original position and prohibits it to perform counting, and an enable signal is supplied to the control input of the counter 14. With the specified delay time set by the setting element 12 of the settings of the first AR cycle, sends a signal through the element OR 15 to the working input of the memory element 7. The driver from the output of the memory element 7 through the OR element 9 and the actuating element 10 is fed to the actuator 11, turning on the switch 6. The counter 14 is reset and the signal at the working input of the memory element 7 returns the memory element to its initial state, and 3 times starts.

Element 3 of the time provides a detuning from repeated switching on of the switch b to a stable k.Z. and triggered by a time longer than the maximum response time of the junction relay protection with switch 6.

If the switch 6 is turned on unsuccessfully for the first time and it is turned off, the element 3 does not have time to work and does not put the memory element 7 into a working state.

When the time is set by the counter 14 pulses, the sp1-dial with the first time delay after 15 due to the unpreparedness of the memory element 7 does not cause the switch to turn on. After dialing the time delay corresponding to the second niiK.iy AR, the signal from the counter 14 nm1 -; 1s through the element

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13 of the settings and the OR element 16 is fed to the working input of the memory element 8. The input signal of the latter through the element OR 9 acts on the actuating element 10, which by means of the actuator 11 switches the switch 6 on. If unsuccessful. switching on the switch 6 after the second reclosure cycle and turning off the switch of the subsequent switching on of the switch is not performed due to the unpreparedness of memory elements 7 and 8,

In case of violation of the circuits of the setting items 12 or 13, the signals to the items OR 15 and OR 16 are supplied, in addition to the setting items, with time delays exceeding the corresponding setpoints. Using the diagnostic control to change the time delay of the AR, you can determine the failure of the AR device;

The decommissioning of the first and second cycles of AR

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connections between the outputs of the memory elements 7 and 8 and the inputs of the element OR 9.

Claims (1)

Invention Formula The automatic reclosing method (ARC) of high-voltage circuit breakers, at which the inrush of the short circuit current is recorded, the current is not present after the surge, and through the pauses selected in accordance with the ARC breaker, the corresponding switch is re-activated, characterized in that reliability of diagnostics of emergency disconnection of connection switches, duplicate the signal for re-activation, in each crater, with a one-time pause, one-half of the automatic reclosure is chosen more than the pause of the first battery vuhkratnogo reclosure pause duplicative signals exceed a predetermined pause times range Dubbing not equal pauses other times range reclosure 1 FIG. 2