SU1436179A1 - Method of cascade-like isolation of faulty portion of sectionated power transmission line - Google Patents

Abstract

The invention relates to the emergency control automation of power lines, mainly for agricultural purposes. The purpose of the invention is to increase the reliability of power supply to consumers connected to the line. When a steady short circuit is disconnected at the head of the circuit breaker and, if the duration of the absence of voltage exceeds the setting value of the first cycle of automatic reclosing, the shutoff devices are disconnected. Turn on the auto-reclosing head switch and sequentially apply voltage to the sectioning devices, which are turned on for a given time, and after switching on, compare the duration of the presence of voltage on the sectioned device and the maximum current protection setting of the main switch. The prohibition of disconnection of the sectioning apparatus is introduced in the case when the duration of the presence of voltage exceeds the set value of the overcurrent protection of the main switch. When the sectioning device is turned on for a short circuit, the head switch is turned off and this sectioning device is disconnected to the first blank pause of the automatic reclosing cycle by the fact that the length of the voltage on the sectioning unit after the device is turned on and the setting value of the maximum current protection of the head switch. The voltage in the intact areas is restored by automatically turning on the main switch. 1 il. (f. C o:; o

Description

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The invention relates to the power industry, namely to the means of automatic emergency automation of power lines, mainly for agricultural purposes.

The purpose of the invention is to increase the reliability of simplifying the device implementing the method.

The drawing shows a two-sided power line diagram and a block diagram of a sectional apparatus (CA) control unit, explaining the cascade separation of the damaged section.

A device that implements the method, contains the head switches 1 and 2 inter-reserved power lines. These switches have relay protection units 3 and automatic-20 re-activation (AR) 4. The lines are connected through normally disabled CA 5 and repeatedly partitioned by CA 6 equipped with control units (CU) 7. CU 7 CA contains sensors 8 and 9 eg two elements OR 10 and II, five elements AND 12 - 16, three elements - 19, three delay elements 20 - 22, two elements 23 and 24 of memory (triggers),

The control unit operates in the cascade lane of the Damaged area as follows. In normal mode, at the output of elements 10 and 12, the signal corresponds to logical 1. From the output of element 12, this signal is fed to the input of element 17, is drawn, and the logical signal is fed to the second input of element 13. The signal from the output of element 10 is inverted by element 18 and the signal O arrives at the first input of the element 15. Thus, at the output of the elements 13 and 15, the signal of logical O. The signal of logical 1 from the output of element 12 and sets the trigger 23 to the state of logical O-output, and the trigger 2A to the state logical 1 at the output. In the event of a stable short-circuit (short-circuit), the main switch is switched off. The first pause of the ARF follows. At the same time, at the output of the elements OR J.O is logical O, the element 12 is logical O, the signal of logical 0 from the output of element 12 is inverted by the element NOT 17 and the signal of logical 1 is fed to the input of elements 21

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and 22 delays, which determine the off delay for the second and first pauses & Auto Recloser.

Since the first input of the element AND 13 from the output of the element OR 10 is dogic O, then the output of this element is also logical O, which goes to the R-input of the trigger 23, the S-input of which from the output of the element 12 also receives a logical O. As a result, the state of the logical O at the output of this element does not change. Logic O is present at the second input of element 15, therefore, trigger 24 is a logical Q at S-input, and logical 0 from the output of element 12 is also at the R input. At the output of trigger 24, the state 1 is stored. This signal is inverted by the element NOT 19 and the logical signal O arrives at the second input of the element 14, prohibiting the shutdown of the automatic reclosure in the first pause.

The automatic reclosing unit 4 turns on the main switch on a non-resistive to, z., Which leads to the disconnection of the main switch of the maximum current limit.

In the second bestekovuyu pause, the signal of logical 1 is fed to the first input of the element OR 11, which leads to the shutdown of the SA 6.

It should be - the inclusion of the head switch from the second ARC ARC. Since the voltage appears on one side of the SA, the output of the element is OR 10. A logical 1 signal appears, and a logical I signal appears at the output of AND 13, which sets the trigger 23 to the logical 1 state at the output. This signal arrives at the second input of the element 15, the first input of which receives a logical signal o from the output of the element fffi 18. To the s input of the trigger 24 receives a signal of the logical o from the output of the element 15, and the r input also the logical signal from the output element And 12, which leads to the preserved-. At the output of the trigger 24, logic 1, which arrives at the second input of element And 16. At the first input of element 16, the signal of logical 3 arrives with a delay defined by element 20, which leads to the activation of the SA.

If the activation of the SA occurs in an intact region, the circuit returns to its original state, i.e. turning off the SA can occur only during the second dead time, similarly to that described. If the activation of the CA occurs on the damaged area, the on-off switch is turned off by overcurrent protection.

In the first blank pause cycle ALV on the R-input of the trigger 23 receives a logical About with the output element And

13, and the S-input is a logical O

from the output of the element 12, therefore, the connection of the logical 1 at the output of the trigger is preserved. This signal arrives at the second input of the element 15, the first input of which receives logical 1 from the output of the element 18. Logical 1 from the output of the element 15 enters the S input of the trigger 24 and the R input of which enters the logical 0 from the output of the element 12 that sets trigger 24 to a state of logical O on the output. This signal is inverted by the HE element 19 and the logical 1 is fed to the second input of the AND 14 element, the first input of which with a delay less than the first pause of the AR cycle defined by the delay element 22 also receives logical 1. At the second input of the OR 1) element signal is logical 1 from the output of the element

14, which leads to the deactivation of CA.- After switching on the main switch in the automatic reclosing cycle, the R-and S-inputs of the trigger 24 receive logical o signals, which leads to the preservation of logical Oi at its output. This signal is fed to the input element

And 16 and prohibits the inclusion of SA.

Thus, the method of cascade separation of a damaged section of a transmission line with double-sided power supply allows increasing the reliability of electricity supply to agricultural consumers by simplifying the insertion of a damaged section, reducing the cost of partitioning points due to the possibility of using simplified devices with limited disconnecting power and increasing the service life of installed sections. on line SA by reducing the number

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the operations they perform in the process of isolating a damaged power line.

Claims (1)

Invention Formula The method of cascade separation of a damaged section of a partitioned power line, in which the line circuit was fixed from the inrush current, the head switch of this line and the sectioning devices were disconnected, after turning on the head switch in an automatic reclosing cycle, sectioning devices are sequentially turned on They are characterized in that, in order to increase the reliability of the load, they fix the short circuit current only on the main circuit breaker In addition, the absence of voltage on all sectioning devices is additionally measured by comparing it with the time setting of the first cycle of the automatic switching on of the main switch and, if the duration of the absence of voltage is greater than the setting value of the first cycle of automatic switching on, the sectioning devices are turned off switch in the second cycle of automatic reclosing and subsequent switching on of the sectioning apparatus; the presence of a voltage on each sectioned device that is turned on compares it with the time setting of the maximum current protection of the main switch and, if the duration of voltage on this sectioning device is greater than the setting of the maximum current protection of the head switch, disable this sectioning device, If the duration of the voltage on this securing unit is equal, the setpoint of the maximum current protection of the head switch is disconnected to currentless pause the sectioning apparatus and prohibit the switching on of this apparatus when voltage is applied to it. Compiled by Yu.Postnikov M.Blanar Tehred I.Veres Corrector V.Romanenko Order 652/51 Circulation 651. VIIIPI State Committee of the USSR for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5. Subscription