SU790320A1 - Thyristorized dc switch - Google Patents

Description

one

The isoburn refers to a pulse technique, in particular, to thyristor regulators of direct current.

A thyristor switch of direct current is known, which contains a working thyristor with a load in the anode circuit and a parallel artificial switching circuit consisting of successively. connected to the switching thyristor and capacitor, and the charging resistor I.

The disadvantage of such thyristor switches is the presence of energy losses in the charge resistor and low reliability of operation, due to the limitation of the current of the natural yepir or the switching thyristor.

The closest in technical essence to the proposed one is a thyristor switch of direct current, in which, instead of a charging resistor, an additional switching circuit is included, consisting of throttles and an auxiliary thyristor for recharging capacitor 21.

However, the question of the reliability of operation of such a thyristor key remains open, since a breakdown of the current inversion is possible.

while simultaneously turning on two thyristors.

The purpose of the invention is to increase the reliability of operation of a thyristor dc switch.

The goal is achieved by the fact that in a thyristor switch of direct current, containing a working thyristor with a load in the anode circuit and

10 parallel artificial switching, consisting of a series-connected capacitor and switching thyristor, the capacitor is divided into two sections, the common output of which is connected to the bus plus a power source through the primary winding of the transformer, the secondary winding of which is connected by one diode to the bus minus the power source, and another conclusion - with the anode of the working thyristor.

The drawing shows an electric circuit, the scheme of the proposed device.

va.

A thyristor DC key contains a working thyristor. 1, load 2, switching thyristor 3, capacitors 4 and 5, transformer 6 and diode 7.

thirty

The device works as follows. .

A direct current voltage is applied to the thyristor switch according to the polarity indicated on the drawing. In the absence of control signals, the working and switching thyristors 1 and 3 are closed, the capacitors 4 and 5 are discharged, the load 2 is disconnected. When a positive impulse is applied to the control electrode of the working thyristor, load 2 is switched on. Simultaneously, capacitor 4 is charged through the primary winding of the transformer. The current pulse of the capacitor 4, the passage of the MS to the primary winding of the transformer 6 f causes an emf in its secondary winding with polarity indicated in the drawing. This EMF causes a charge current of a capacitor 5, which passes through a capacitor 4, a thyristor 1 and 7. When a positive pulse is applied to the control electrode x,; thyristor 3 is its inclusion. At the same time, the sum of the voltages of the charged capacitors 4 and 5 is applied to the thyristor 1, locking it and turning off the load 2. We know that the total voltage of the coconvs 4 and 5 is always higher than the voltage of the power supply, ensuring the necessary supply of power for hoping to turn off the thyristor 1, voltage fluctuations in the network do not cause aza in the operation of the thyristor key. , the operation of the thyristor circuit is repeated. In the absence of control signals. -. Juvwx signals, the circuit is brought to its original state, with the operating and switching thyristors being turned off.

The division of the switching capacitor into two sections and the introduction of a transformer into the circuit of a thyristor dc switch eliminates the possibility of disrupting the switching of the load current, and, consequently, increases the reliability of the device.

invention formula

A thyristor switch of direct current containing a working thyristor with a load on the anode circuit and a parallel artificial switching circuit consisting of a series-connected capacitor and a switching thyristor, characterized in that, in order to increase reliability, the capacitor is divided into two sections, the common output of which is connected to the bus -plus power source through the primary winding of the transformer, the secondary winding of which is connected via a diode to the minus of the power supply through one diode and the working lead to the anode of the thyristor.

Sources of information taken into account during expert giza

1.Volkov I.V., Vakulenko c. M., Sources of power lasers.

K., Technique, 1976, p. 158, Fig.88.

2.Kreizberg.M. I. and Shikut E, V. Pulsed methods of regulating direct current circuits using thyristors. M., Energie, 1969, - p. 21 fig. 9 (prototype).

Claims (1)

Claim DC thyristor switch containing a working thyristor with anode load and a parallel artificial switching circuit consisting of a series-connected capacitor and a switching thyristor> characterized in that, in order to increase reliability, the capacitor is divided into, ¹ two sections, the common output of which is connected with the bus plus the power supply through the primary winding of the transformer, the secondary winding of which is connected to one output via a diode, and the bus minus the power supply to the other with the anode and ~ thyristor.