SU1457013A1 - Signal device of system for monitoring relay protection operability - Google Patents

Abstract

The invention relates to the field of electrical engineering, in particular, to relay protection and emergency control automation of electrical installations, and is intended to signal the activation and monitoring of the health of multi-stage relay protection without removing them from work and without disabling the protected object. The aim of the invention is to expand the functional

Description

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The invention relates to relay protection and emergency automation of electrical installations, and is intended to signal the actuation and monitor the operability of discrete automation equipment, for example, multi-stage relay protection devices without removing them from operation and disabling the protected object.

The purpose of the invention is to enhance the functionality and reduce the monitoring time by parallel testing of all protection levels.

The drawing shows a diagram of the proposed device.

The device for signaling and monitoring of relay protection contains input block 1, n measuring logic 2 and output blocks 3, block 4 relay protection, the number of measuring logic blocks equal to the number of its steps, switching mechanism 5 switching device n RS-triggers b, source 7 control signals, a key of control 8 with a neutral position, containing the first 9 and second 10 closure contacts, the first elements I-11, the first 12 and the second 13 indicators, the OR element 14 and the second elements 15, the number of which as well as in the first elements of the And, RS-triggers and the first indicators is equal to the number of stages of protection.

The device works as follows.

The signal carrying the information about the state of the protected object is formed in the input unit 1 by means of, for example, current and voltage transformers, and from its outputs is fed to the inputs of the relay protection unit 4. In the absence of an emergency on the protected object no

signals on measuring and logic blocks 2 of all protection stages, on the inputs and output of its output block 3, on the input of the switching device switching mechanism 5. AT

the mode of operation of the device without control, the control key 8 is in the neutral position, its closing contacts 9 and 10 are open. In this case, the signals at the inputs and outputs of the RS-flip-flops 6, the first 11 and second 15 elements AND, the element OR 14 are missing, and all the indicators 12 and 13 are turned off. When the state of health is monitored, the first pin 9 of the control key 8 is closed. The signal from the source 7 of the control signal: the signal goes to. the direct inputs of the first elements 11 and appear on their outputs, since there are no signals at the inverse entrances of the e-elements, the signals from the outputs of the first elements 11 are fed to the corresponding inputs of the measuring unit 2 of the logical blocks 2 of the relay protection 4 and through the OR element 14 to the input of the second indicator 13. The latter is turned on, and the relay protection 4 begins to be checked. Since the response time of the various stages of the relay protection 4 increases with an increase in their numbers, when it is in good condition, the signal appears first at the output of the measuring and logic unit 2, the first protection stage, from where it is given to the first input of the second element 15 and at the first input of output block 3, then at its output and

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arrives at the second inputs of all the second elements And 15 and mechschism 5 switching switching apparatus. The second element is AND 15,;, which has signals on both inputs .-. 0

From the output of the element 15, the signal goes to the S input of the RS flip-flop 6, which switches, as a result of which the signal from its output is fed to the inverse input of the first element 11 and to the first indicator 12. The latter is turned on, indicating that the first stage of the relay protection 4 is in good condition, and the signal at the output of the first element 11 and the associated input of the measuring and logic unit 2 of the first stage of protection disappears. Since the signal from the input of the measurement logic unit 2 of the first protection stage disappeared, it returns to the initial state. The signals at the output of the measuring logic unit 2,, at the output of the relay protection unit 3, 4, at the outputs of the second elements I 15, at the S input of the RS flip-flop 6, disappear, and the switch of the object cannot be turned off. The first indicator 12 remains on, indicating that the first stage of relay protection 4 is in good condition, the second indicator 13 continues to light, indicating that the monitoring mode continues.

After the countdown. The second stage of protection appears at the output of its measuring logic unit 2j, from the output of which is fed to the first input of the second element I, and, having passed through the output unit 3, is fed to the switching mechanism of the commuting device 5 and to the second inputs of all the second elements 15. The second element 15 is operating., the RS-flip-flop 6 is switched, the first indicator 12 lights up, the second stage of the relay protection 4 is in good condition, and the signal from the input of the measuring-logic unit 2j is removed as a result with the output of the RS flip-flop 6, j to the inverted input of the first element I 11. The second stage of the relay protection 4 returns to the initial state, and the switch on the protected object does not have time to turn off.

Similarly, the health check of all

the following stages of relay protection 4. If the relay protection 4 is in good condition, after checking its last stage, the second indicator 13 goes out, indicating the end of the monitoring mode, and all the first indicators 12 remain on, and each of them indicates a good condition steps relay zapshty 4.

In order to remove the signals about the operation of the relay protection 4 after the end of the relay, the control of its operating state closes the second contact 10 of the control key 8. In this case, from the source 7 of the control signal, a signal is sent to the R-inputs, all RS-flip-flops 6. The latter switches to the initial state, the signals at their outputs disappear and the first indicators 12 turn off. After returning the control key 8 to the neutral position, the circuit of the entire device returns to the initial state.

If "some level of relay 4 is faulty, the signal does not appear at the output of the corresponding measuring unit 2, the corresponding second element 15 does not work, the corresponding RS flip-flop 6 does not switch and the corresponding first indicator 12 does not turn on , signaling the failure of this stage of relay protection. The second indicator 13 in this case, after the end of the monitoring mode, remains in the on state, indicating that a signal is being input to the input of the defective protection stage. The return of the circuit of the entire device to the initial state is necessary, as in the first case, to first close the second contact 10 of the control key 8, and then transfer it to the neutral position.

Thus, according to the status of indicators 12 and 13, the outcome of the test is recorded and the state of the relay protection 4 is determined. A long-term activation of the second indicator 13 and the absence of any of the first indicators 12 indicates a malfunction of the corresponding power level. Short-term activation of the second indicator 13 at the time of the test and long-lasting illumination of all the first indicators 12 indicates

about the good condition of all levels of protection. In addition, according to the status of indicators 12 and 13, one can judge the health of the control device itself. For example, the non-ignition of any of the first indicators 12 and the extinction of the second indicator 13 after the termination of the monitoring mode indicates that the signal for checking the corresponding relay protection level 4 was not applied to the input of its measuring and logic unit.

When the action of relay protection 4 as a result of a short circuit to

to the protected object, the signal from the output of the measuring logic unit 2 that operated it goes through the output unit 3 to the switching device switching mechanism 5, by disconnecting the switch, to all the second inputs of the second elements 15 and to the first input of one of Them corresponding to the number of the activated protection level , causing a trigger, From the output of this element, the signal goes to the corresponding RS-flip-flop 6, which is thrown, causing the activation of one and the first indicators 12. The switched-on indicator 12 signals about operation of relay protection 4 through a chain of the corresponding level,

After the switch-off of the protected object is turned off, the relay protection 4 returns to the initial state and does not interfere with its automatic reclosure. If the short circuit self-destructs during the current-free pause, the automatic reclosure is successful.

In order to remove the signal for the relay protection 4 to operate on a chain of any of the stages as a result of a short circuit on the protected object, memorized by the corresponding RS-trigger 6, the second contact 10 of the control key 8 is closed. At the same time, from the source 7 of the control signal, the R-inputs of all RS-flip-flops 6 receive a signal, the RS-flip-flop 6 triggered returns to the initial state,. the signal from its output disappears and the corresponding first indicator 12 turns off. After returning the control key 8 to the neutral position, the circuit of the entire device returns to the initial state.

Thus, in the proposed device, the RS-flip-flops 6 and the first indicators 12 simultaneously perform the functions of a signal authority, fixing the operation of the relay protection 4 along a chain of any of the steps during a short circuit on the protected object.

The device does not require alternate switching over the stages of relay protection in the monitoring mode, which increases the reliability of its operation and significantly reduces the monitoring time due to parallel testing of all stages of the multi-stage relay protection. In addition, for the multistage relay protection, the proposed device allows the functions of the signaling bodies to activate each of the stages as a result of short circuits at the protected object and as a result of periodic operational checks, which reduces its cost and increases the reliability of operation.

Claims (1)

Invention Formula A device for signaling the control of the operability of the relay protection, including a series-connected input unit, measuring logic units, an output unit and a switching device switching mechanism, containing a signal control source, the output of which is connected via a first closing contact of the control key with neutral position the input of the first element And, the output of which is intended to be connected to the input of the first stage of the measuring-logic, relay protection unit, RS-flip-flop, the output of which is The first indicator is connected with the second indicator and the inverse input of the first element I, and the R input is connected to the second closing contact of the control key with a neutral position; the second indicator differs in that, in order to expand its functionality and reduce the monitoring time by parallel testing of all steps , an additional element is OR, n is the second of the AND elements, n-1 of the first AND elements, serially connected n-1 RS-flip-flops and n-1 first indicators, while the direct inputs of all the first AND elements are combined, inverse the inputs of the additionally introduced first elements And are connected to the outputs of the newly introduced RS-trig 71457013 their outputs are intended to give the corresponding second elements to the inputs of the measuring devices I, the first inputs of which the prediagnostic blocks are correspondingly designated to be connected to the outputs of the stages of the relay protection unit and the measuring-logic blocks corresponding to the inputs element S1I, the output steps of the relay block of the block which is connected to the second display panel, the second inputs are combined and the predator, the R-inputs of all RS-flip-flops are assigned to be connected to the output, the S-inputs are connected to the output-output about block.