SU1376129A1 - Device for checking relay protection for serviceability - Google Patents

Abstract

FIELD OF THE INVENTION The invention relates to electrical engineering, in particular, to devices for relay protection and checking the operability of blocks. The aim of the invention is to increase the reliability of the control. The invention allows for automatic monitoring of the health of the relay protection unit and periodic testing of the health of all elements of the device. Periodically, the response time of the time element 9 from its output receives a signal at the input of the trigger 7, which switches and sends a signal through the closing contact of the operating lining 8 to the enabling input of the key element 6 connected between the source 5 of the control signal and the input of the measuring and logic unit 2 of the relay protection . After the relay protection unit 2 triggers, the trigger, by switching, opens the key element 6 and starts the time element 9. To check the circuit elements of the device, open the contact of the operating patch 8. The intact state of the relay protection unit 2 and all the elements of the device is indicated by the turning on of the indicator 11 with the operating patch 8 open and the non-switching on when closed. 1 il. W (L S

Description

The invention relates to the field of electrical engineering, in particular, to devices of relay protection and emergency control of electrical installations.

The purpose of the invention is to increase the reliability of control of relay protection.

The drawing shows a block diagram of a device for monitoring the health of a relay protection.

The device contains an input unit 1 ,, measuring-logic unit 2 of relay protection, an output unit 3 of relay protection, a switching mechanism 4, a source 5 of the control signal, a key element 6, the output of which is connected to the input of the block 2 of relay protection. Operator is connected to the output of the trigger 7 lining 8. The trigger 7 is made in the form of RS-trigger. The output of the operational lining 8 is connected with the permissive input of the key element 6 and the blocking input of the output block 3 of the relay protection, which is made in the form of a logic circuit. To the output of the trigger 7 is also connected the inputs of the elements 9 and 10 of the exposure time. For a time delay element 9 having a delayed response time, the trigger is a zero signal. The time of its operation corresponds to the frequency of checks of the relay protection unit 2. The output of the time delay element 9 is connected to the S-input of the trigger 7, the R-input of which is connected to the output of the relay protection unit 2. The output of the time delay element 10 is connected to the input of the indicator 11. The time delay element 10 has a response time delay, the value of which by the safety factor exceeds the 1 time response time of the relay protection unit 2.

The device works as follows.

In the initial state, the input of the relay protection unit 2 through the input unit 1 continuously receives a signal about the state of the protected electrical equipment. When the alarm components in this signal of the relay protection unit 2 are triggered, the output unit 3 of the relay protection also triggers a signal to the relay mechanism 4, which deactivates the damaged electrical equipment.

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When the time delay element 9 is triggered, its output receives a signal at the S input of the trigger 7, which at the same time switches to state 1, removes a zero signal from the input of the time delay element 9 and sends a signal through a closed operational pad to the blocking input output block 3 of the relay protection and on allowing the input of the key element 6.

The key element 6 is then opened and the control signal from the source 5 of the analog control signal is fed to the input of relay protection unit 2. When relay protection unit 2 is triggered, the signal from its output goes to the R input of the trigger 7, which switches to the O state and removes the signal from the enabling input of the key element 6 and the blocking input of the output unit 3. In this case, the relay protection unit 2 is put into operation as intended. The return time of the relay protection unit 2 to the unset state is less than the time of the 4 switching mechanism movement. After switching the trigger 7 to the state O, the start-up zero signal arrives at the input of the element 9. The time delay element 9, after a response time which can be from several hours to several days, sends a signal to the S input of the trigger 7, and the test of the relay protection unit 2 is repeated.

In the case of failure in the operation of the relay protection unit 2, the signal at its output does not appear during the test, the trigger 7 is in the state O for a time longer than the response time of the time delay element 10, as a result of which the input of the indicator 11 receives the signal output element 10. The operation of the indicator 11 -signalizes the fault. The indicator 11 is also triggered in case of faults of the type of open circuit in the source 5 of the control signal and in the key element 6. In order to increase the reliability of the operation of the key element 6, the principle of duplication can be applied to the closure, for example, by connecting two analog keys in series. In this case, the reliability of the analog switch to close is doubled, and doubling the likelihood of an open circuit type fault is compensated by the fact that such a fault will be detected when checking the relay protection unit 2.

If the connection between the output of the relay protection unit 2 and the R-BXO trigger house 7 fails after the response of the unit 2 from the control signal of the trigger 7 to the state O does not occur. In this case, the relay protection unit 2 does not affect the switching of the switching mechanism 4, since the presence of a signal at the blocking input of the output unit 3 prevents the signal from passing to the input of the switching mechanism. After the relay protection unit 2 has been triggered, the time delay element 10 receives a signal at the input of the indicator 11.

The periodic control of the correctness of the trigger 7, time delay elements 9 and 10, and the indicator 11 opens the operational patch 8. After the time delay element 9 is triggered, the trigger 7 switches to state 1 and sends a signal to the output of the time delay element 10, which actuation sends a signal to the input of indicator 11, the operation of which in this mode indicates the health of the checked elements.

Upon subsequent shutdown of the operating patch 8, the relay protection unit 2 is checked, after completion of which the indicator turns off.

The frequency of checking the elements of the device made by opening the operational lug 8 can be significantly reduced compared to the frequency of checking the unit 2 relay protection due to the fact that the number and complexity of these elements are lower than the complexity of unit 2 relay protection and, consequently, the probability of failure of these elements is lower probability of failure of the relay protection unit 2. In the presence of a central checking device, common to several relay protection units and their control devices, the opening procedure circuit operational laths and the indicator angshiza

for this technical solution can be easily automated.

The proposed device makes it possible to increase the reliability of the operation of the devices for relay protection and emergency emergency automation of electric power plants, as well as to expand the field of application for control of the measuring part of these devices.

Improving the reliability of relay protection devices is carried out by automating the control and, consequently, the possibility of reducing the frequency of inspections. To increase the reliability: the control provides for the possibility of periodically checking the control device without disabling the relay protection unit.

The expansion of the field of application is achieved by the fact that in the proposed device an input is supplied to the relay protection unit from the control signal source. The signal is identical to the signal that enters the input of the relay protection unit from the input unit and carries information about the state of the protected electrical equipment. At the same time, the operation or failure of the measuring part of the relay protection unit is automatically controlled depending on the level of the control signal.

Claims (1)

Invention Formula A device for monitoring the operability of the relay protection, made in the form of a serially connected input, measuring and logic, output blocks and a switching mechanism, containing the source. control signal, connected to the input of the key element, RS-Tparrept whose output is connected to the indicator and the terminal for connecting the input unit to the input of the measuring-logic unit, the R input of the RS flip-flop is connected to the terminal for connecting the output unit to the output of the measuring-logic unit the protection to be tested, the first element of the time delay, characterized in that 4to, in order to increase the reliability of the control, an operational overlay, a second element of the delay time, and a key element with a second permit om, RS-trigger output conn 51376129 6 not through the operational pad svpsod which is connected to the S-input the second enable input of the trigger key, between the output of which and element, the output of which is switched on by the second element Whose time allowed to connect to the terminal for connecting the input of the measuring-logic unit, the key element is equipped with a terminal An input is connected to the output of the RS flip-flop at the input. The prohibition of the out of time element, the travel unit, is prohibited.