SU1297163A1 - Device for checking conditions of converter thyristors - Google Patents

Abstract

The invention relates to electrical engineering, in particular, can be applied to monitor the state of sequentially and in parallel operating thyristors in converter devices. The aim of the invention is to increase the reliability of the device for monitoring the state of the thyristors of the converter. This goal is achieved by using reed relays with windings 2.1, ..., 2.k and 3.1, ... n for monitoring currents, and to increase the life of their work, the monitoring is performed periodically so that the specified relays work only for 1 / 100 converter running time. 1 il. with $ (L NO CO vi t i 4 i- i ... u u

Description

The invention relates to electrical engineering and can be applied to monitor the state of serially and in parallel operating thyristors in converter devices.

The purpose of the invention is to increase the reliability of the device.

The drawing shows a schematic diagram of the device for monitoring the state of the thyristors in the unit.

The thyristor unit consists of n parallel-connected branches, with k thyristors connected in series in each branch. Each thyristor (designation introduced for the first of identical parallel branches) 1.1, 1.2, ... 1.k is shunted by a damping circuit designed to eliminate overvoltages on the series-connected thyristors, as well as to create magnetic fields using coils connected in series. The magnetic fields of these coils have reed relay contacts 2.1,

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then regardless of the operation of the tirisyurop, the contacts of the reed switches will be closed. Work control (state) ty1

The resistors are made only in the time intervals when the windings of the main relays are de-energized. At the same time, the service life of reed switch contacts increases in proportion to the duty cycle of the reed switch, i.e. the ratio of the full cycle time (the total time of the on and off state of the winding of the reed relay) to the time of the off state of the winding of the reed relay. Let, for example, 5. The importance is 100 (for example, for 10 minutes the reed switch is connected to a constant voltage source, and disconnected for 6 seconds), then the contact life of the reed switch will be approximately 28000-280000 h The duty cycle is set by the generator 5 pulses, and the time of the on and off state of the winding of the reed switch depends

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2.2, ..., 2.k. To control the current in connection with a particular converter, parallel-connected branches of x with a tiris device. Suppose that one of the tori is installed in the power current-carrying parts reed relays 3.1, 3.2, ..., 3.p. The windings of all specified reed relays are connected sequentially.

the thyristors of the first branch, for example 1.k, went out of order in such a way that its resistance became equal to infinity - (ti). In this case, the reed

They can also be switched on and parallel-relay 3.1 in the monitoring interval, and will not be powered from a controlled source, its contact will be a direct-current source switching on and the corresponding LED of the switching device 4, for example, will not be lit. The total current to the transistor, the duty cycle of which the input of the block 8 changes, is triggered by the generator 5, it is audible first, and for manual switching off the windings of the reed relay, a button or contacts 6 of the electromagnetic relay are provided (for potential isolation). 40 of the first branch, for example 1.k, entered the contacts of reed switches 2.1, 2.k all of them so that it became uncontrollable e-branches through LEDs connected to

After the specified time has elapsed, the thyristor converter is disconnected. Further suppose that one of the thyristors

I have zero resistance (short circuit). Then, in the monitoring time interval, the contacts of the reed switch 1.k will not close, since the current in the damping circuit will be equal to zero, and the corresponding LED will not illuminate. The total current at the input of block 7 changes, the signaling will start at the beginning, and after a predetermined time, the thyristor converter turns off.

unit 7 beeper and protection. Contact reed relay 3.1,.,. Z.p through other LEDs are also connected to the unit 8 beep, lizatsii and protection.

The device works as follows .50

During normal operation of the thyristor unit, alternating current flows through all the monitored circuits 1.1, ..., 1.k, 3.1, ... 3, n and the contacts of the reed relays are closed and open with the corresponding frequency if the windings of the reed relays are de-energized . However, if the windings of the reed relays are connected to a constant voltage source,

then regardless of the operation of the tirisyurop, the contacts of the reed switches will be closed. Work control (state) ty1

The resistors are made only in the time intervals when the windings of the main relays are de-energized. At the same time, the service life of reed switch contacts increases in proportion to the duty cycle of the reed switch, i.e. the ratio of the full cycle time (the total time of the on and off state of the winding of the reed relay) to the time of the off state of the winding of the reed relay. Let, for example, 5. The importance is 100 (for example, for 10 minutes the reed switch is connected to a constant voltage source, and disconnected for 6 seconds), then the contact life of the reed switch will be approximately 28000-280000 h The duty cycle is set by the generator 5 pulses, and the time of the on and off state of the winding of the reed switch depends

0

Relay 3.1 will not operate in the monitoring interval, its contact will open and the corresponding LED will not light. The total current at the input of block 8 will change, the acoustic signaling will work first, and on the first branch, for example 1.k, it will be disabled so that it becomes uncontrollable

After the specified time has elapsed, the thyristor converter is disconnected. Further suppose that one of the thyristors

Relay 3.1 will not operate in the monitoring interval, its contact will open and the corresponding LED will not light. The total current at the 35 input of the block 8 will change, the sound alarm will work first, and on the first 40 branch, for example 1.k, it went out of order so that it became uncontrollable

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I have zero resistance (short circuit). Then, in the monitoring time interval, the contacts of the reed switch 1.k will not close, since the current in the damping circuit will be equal to zero, and the corresponding LED will not illuminate. The total current at the input of block 7 changes, the signaling will start at the beginning, and after a predetermined time, the thyristor converter turns off.

The proposed device has increased reliability due to an increase in the life of reed relays, in particular, under the conditions described above, it is about 30 years.

312971634

Claims (1)

The formula of the invention is characterized in that, with The device for monitoring the state with the aim of ensuring reliability, in it the thyristors of the converter, is connected to the pulse generator, the reed switches are subsequently into groups, the on-relays are divided into two groups, the parallels of the first group and 5 relays of the first group are intended for those equipped with parallel damping in magnetic fields with conductive circuits, each of which are damping circuits, and the relay from the series connected in series to accommodate a magnetically resistor and a capacitor containing The electric fields of the power circuits are reed relays intended for Okalsda from thyristor groups, while the locations in the magnetic fields of the wire-controlled current source are made in NIKES with controlled currents, when there is nothing connected in series with the excitation winding of said re-controlled source the current and the control are connected to a controllable source of the current key, the control input of which is current, and the contacts are connected to the t5 is connected to the generator output to the inputs of the protection actuator, pulses.