SU843088A1 - Device for protecting thyristorized converter - Google Patents

Description

(54) DEVICE FOR PROTECTION OF THYRISTOR TRANSMITTER

one

The invention relates to electrical engineering, in particular to converter equipment, and may find application in protection devices for thyristor converters.

A device for protecting a thyristor-Vo converter is known, which contains an arc switch, which suppresses a capacitor by a charging circuit and diodes 1.

A disadvantage of this device is its complexity.

The closest in technical means and the achieved result is a device for protection of a thyristor converter containing a switching valve and an extinguishing circuit of a series-connected capacitor, reactor and a diode, the cathode of which is connected to the positive clamp of the direct current of converter 2.

The disadvantage of this device is insufficient performance.

The purpose of the invention is to increase the speed of performance.

The goal is achieved by the fact that the device is equipped with three diodes, the anodes

which are connected to the terminals of the AC converter, and the cathodes are connected to the capacitor, and the switching valve is connected parallel to the capacitor and the reactor.

The drawing shows a diagram of the device.

The converter consists of a transformer 1, cathode 2-4 and anode 5-7 thyristor groups, separation diodes 8-10, quenching capacitor I, reactor 12, switching valve 13, charge thyristor 14, diode 15, load 16.

Claims (2)

When applying voltage from a transformer. 1, the thyristors 2-7 of the converter are supplied with a control pulse to the charging thyristor 14 and the quenching capacitor AND is charged. The capacitor voltage has the polarity indicated in the drawing. Let the emergency mode occur when the current is conducted by the thyristor 2. When the emergency current sensor command is taken off. control pulses from thyristors 2-7 and a control pulse is applied to the switching valve 13. The switching valve 13 opens the damping capacitor 11 around the circuit and, 13, 12, 11 does not charge until the reverse polarity is applied. In the process of recharging and extinguishing the capacitor 11 to a reverse polarity voltage, a reverse voltage is applied to the thyristor 2 conducting the emergency current, And, 12, 15, 2. Under the action of this voltage, the thyristor 2 is closed and the emergency current is interrupted. In the same way, the process of locking thyristors 3, 4 occurs when an emergency current flows through them. After the termination of the emergency current, a control pulse is applied to the thyristor charge And, the capacitor 11 is charged, and then the transducer is switched on again. The invention of the Device for the protection of a thyristor converter containing a switching vein gr f f y / VIS- - -i t8 70 I / 2/4 type and quenching circuit of a series-connected capacitor, reactor and diode, the cathode of which is connected to the positive DC clamp of the converter, characterized in that in order to improve performance, it is equipped with three diodes whose anodes are connected to the terminals of the AC the converter, and the cathodes are connected to a capacitor, the terminal valve being connected to the parallel capacitor and the reactor. Sources of information taken into account in the examination 1. USSR author's reference to application ff 1497324 / 24-07, cl. H 02 H 7/10, 1970. 2. Author's svdedetstvo USSR for application number 413571, cl. H 02 H 7/10, 1974.