SU1029302A2 - Device for checking phase alternation in three-phase power network - Google Patents

Abstract

DEVICE FOR THE CONTROL OF THE MULTILATION OF THE PHASES OF THE THREE-PHASE NETWORK St. No. 936173 is different in that, in order to expand its functionality, by increasing the signals of the information on the state of the monitored object, it additionally introduces a second actuator and a Ban element, the direct input of which is connected to the output of the first actuator, and the inverse input to the output of the second actuator, the input of which is connected to the output of the threshold element, and the outputs of the Ban element and the second actuator are outputs of the device.

Description

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The invention relates to electrical engineering and may be HcnOvibsosaHo in accident protection schemes, in particular in the control circuits for the presence and order of phase alternation in three-phase networks.

According to the main author. St. No. 936173, a device is known for controlling the alternation of the phases of a three-phase network, comprising a threshold element whose output is connected to the second inputs of the first, second and third elements AND, and the input through diodes with three input terminals which are also connected to the first inputs of the first, second and second, respectively The third element And connected to the first input of the first trigger, the output of which is connected to the third input of the second element And the output of which is connected to the first input of the second trigger, the output of which is connected to the third input of ter it ,, AND gate whose output is connected to the actuating body and the second inputs of the first and second flip-flops 1.

A disadvantage of the known device is the impossibility of distinguishing the phase discontinuity mode from the wrong phase alternation mode, since in both types of failures the same actuator is triggered.

The aim of the invention is to extend the functionality by increasing the signals of the state information of the object being monitored.

The goal is achieved by the fact that a second actuator and an Inhibit element, the direct input of which is connected to the output of the first actuator, and the inverse input - to the output of the second actuator, whose input is connected to the output, are additionally introduced into the device for controlling the alternation of phases of the three-phase network. a threshold element, wherein the outputs of the Inhibit element and the second actuator are outputs of the device.

The drawing shows a block diagram of the device.

Device for controlling the alternation of phases of a three-phase network, containing diodes 1, 2 and 3, elements 4, 5 and 6, threshold element 7, two triggers 8 and 9, element 10 Prohibition, first and second executive bodies 11 and 12. Anodes of diodes 1 , 2 and 3 are connected respectively to the input terminals 13, And and 15, the cathodes to the input of the threshold element 7. The output of the element 10 Ban is connected to the output clip 16, and the output of the second actuator 12 - with the output clip 17. The first inputs of the elements And 4, 5 and 6 are connected respectively with the input terminals 13, 14 and 15 of the device, the second inputs - from the output th threshold element 7, the third inputs of AND gates 5 and 6 are respectively connected to v1hodam flops 8 and 9, the installation of the inputs to "1

(single inputs) of the latter are connected respectively to the outputs of the elements 4 and 5, and the installation inputs in “O (zero inputs) - to the output of the element 6 and associated with the input of the first executive body 11. The input of the second executive body 12 is connected to the output of the threshold element 7, and the output is to the inverse input of element 10 Barring, the direct input of which is associated with the output of the first executive

0 authority 11.

A device for controlling the alternation of the phases of a three-phase network operates as follows.

Upon initial switching on, the supply voltage of the trigger 8 and 9 is reset to the initial state, in which, from their outputs, prohibitive signals are sent to the circuits 5 and 6.

Upon receipt of the first pulse (from the input terminal 13) through the diode 1 to the input

0 of the threshold element 7, an output pulse appears at its output, which simultaneously enters the inputs of all AND 4, 5, and 6 circuits. Since the inputs of the And 5 and 6 circuits contain inhibit signals from the outputs of the trigger 8 and 9, the pulse from the output

5 threshold element 7 at the outputs of the circuits And 5 and 6 is not in accordance with. But the impulse from the output of the threshold element 7 to Wits at the output of the two-input circuit And 4, since at its inputs the impulse from the output of the threshold element 7 and the input impulse corresponding to phase A coincide. at its output, and therefore at the input of the circuit, And 5 will disappear. As soon as the next pulse (corresponding to phase B) arrives at

5 input threshold element 7, then at the input of the circuit And 5 all three signals will coincide in time: from the output of the threshold element 7, the input signal (corresponding to phase B) and the enabling signal from the output of the trigger 8. At the same time, a short signal will appear at the output of the And circuit 5 , under the influence of which trigger 9 will work, and at its output. the ban signal will disappear. . Now, as soon as all three signals at the input of the circuit And 6: from the output of the threshold element 7, the input signal corresponding to phase C, and the enabling signal from the output of the trigger 9, the output of the circuit And 6 shows the signal that goes to the input of the first executive body 1 and the other inputs of the trigger 8 and 9. Under the influence of these

Signals last again take the original state.

With the arrival of a new sequence of pulses corresponding to phases A, B and C, all. cycle of work is repeated. Thus, the device operates with the correct

5 phase rotation.

In this case, the inputs of the executive bodies 11 and 12 evenly receive pulses, which the executive bodies

12 and 11 are perceived as normal work. As soon as the input of the device disappears in one phase, then at the inputs of executive organs 12 and 11 one of the pulses disappears and their uniform flow is disturbed.

Both executive bodies 12 and 11 will work, but at the same time from the output of the second executive body 12, the signal will go to the output terminal 17 and to the inverse (prohibiting) input of the element 10 of the Prohibition. Then there is no signal at its output.

Thus, in the event of a phase failure, information on the Vits only at exit 17.

If the alternation of phases is wrong, the uniform flow of pulses is disturbed only at the entrance of the first executive body 11, and the pulses of the second executive body 12 are still received uniformly.

Therefore, only the first actuator 11 operates. From its output, the input goes to the direct input of element 10 Ban, and since there is no signal at its inverse input (the second actuator did not work), a signal appears at the output terminal 16.

This will be the information that a phase interruption has occurred. Thus, if the phase rotation is incorrect, information appears on the input terminal 16, in the event of a phase failure, information appears on the output terminal 17. If any type of device fails, the device detects the type of failure and provides relevant, specific information about it.

The presence of two outputs makes it possible to determine the type of failure, which is the shortening, the time spent by the operator servicing the secured installation, to search for damage and repair damaged equipment.

Claims (1)

DEVICE FOR CONTROL OF PHASE ALTERNATION OF THREE-PHASE NETWORK according to ed. St. No. 936173 characterized in that, in order to expand the functionality, by increasing the signals of information about the state of the monitored object, the second executive body and the Prohibition element are introduced into it, the direct input of which is connected to the output of the first executive body, and the inverse input to the output of the second executive body, the input of which is connected to the output of the threshold element, and the outputs of the Prohibition element and the second executive body are the outputs of the device .. 3>