SU1288839A1 - Control device for converter thyristors - Google Patents

Abstract

The invention relates to electrical engineering and can be used to control thyristors of three-phase and single-phase converters. The aim of the invention is to simplify the device. When a voltage is established on capacitor 12, it is sufficient (L Phage 2

Description

Auxiliary thyristor 6 for unlocking, the latter opens and supplies a control current to thyristor I, which, when opened, passes current through load 3, At a small value of resistance of regulator 4, capacitors 12 do not have time to recharge to unlocking potential, and thyristors 6 each channel 5, and therefore the thyristors 1, are locked. With

The invention relates to electrical engineering and can be used to control thyristors of three-phase and single-phase converters.

The purpose of the invention is to simplify the device.

FIG. 1 shows a device for controlling thyristors of a three-phase converter; 2 shows a device for controlling thyristors of a single-phase converter.

A device for controlling thyristors I of a three-phase converter that includes a supply transformer 2, the secondary winding of which is connected to the cathodes of thyristors 1, to the anodes of which a load 3 is connected, contains a controller 4 of the control signal and 5 channels of control according to the number of thyristors 1, each of which consists from the auxiliary thyristor 6, the control electrode of which is connected to the cathode of the separation diode 7, and the anode through the limiting resistor 8 to the cathode of the charging diode 9 and through the resistor 10 of the RC chain II to the connection point e single output capacitor 12 RC-chain 11 with the anodes Nogo separator 7 and the discharge 13 diodes. The other end of the capacitor 12 is connected to the cathode, and the cathode of the thyristor 6 is connected to the control electrode of the corresponding thyristor 1. The cathodes of the discharge diodes 13 of all the .5 channels are connected to one output of the regulator 4, and the charge diode 9 of all the channels 5 connected to the connection point of the load 3 with the anodes of the thyristors 1 and with the other output of the controller 4.

88839

the large value of the resistance of the regulator 4, the capacitor 12 is almost not charged by the negative polarity of the voltage and, therefore, over-; Its charge occurs at the beginning of the working period, which leads to unlocking of the auxiliary and power thyristors at the beginning of the half period. 2 h. P . f-ls. 2 na.

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A device for controlling thyristors 1 of a single-phase converter contains, in addition, a bridge diode rectifier 14, one DC output of which is connected to another output of regulator 4, the other to load 3, and AC diagonal leads 1 to the cathodes of thyristors 1.

A device for controlling the thyristors of a three-phase converter operates as follows.

During the positive half-period at the cathode of thyristor 1, capacitor 12 is charged along the circuit: diode 13, controller 4 and load 3. In negative half-period at the cathode of thyristor 1, capacitor 12 is recharged through resistors 10 and 8, diode 9 and load 3, Auxiliary thyristor 6 turns off as soon as the voltage on the capacitor 12 becomes sufficient to unlock it. Turning on, the thyristor 6 through the diode 9 and the limiting resistor 8 supplies the control current to the thyristor 1, which, when opened, passes a current through the load 3. The regulator 4 sets the current goal turn thyristors. With a small value of the resistance of the regulator 4, the capacitors 12 do not have time to recharge to the unlocking potential and the thyristors 6 of each channel 5, and therefore the thyristors 1, are locked (there is no current in the load). With a large value of the resistance of the regulator 4, the capacitor 12 is almost not charged by the negative polarity of the voltage and, consequently, it is recharged at the beginning of the working half period, which leads to unlocking of the auxiliary and power thyristors at the beginning of the half period (the current in this case is the greatest).

The device for controlling the thyristors of the single-phase converter works similarly, except that the charge in the positive half-period and recharge in the negative half-period of the voltage of the capacitor 12 of the RC chain 11 of each control channel 5 occurs through the diodes of the bridge rectifier 14,

Thus, by changing the links between the thyristor control channel elements, the device is simplified.

Claims (3)

1. A device for controlling the thyristors of the converter, including the supply transformer, the secondary winding of which is connected to the cathodes of the thyristors, to the anodes of which a load is connected, containing a regulator with a control signal and control channels according to the number of thyristors of the converter, each of which includes an auxiliary thyristor, RC- the chain, charge, bit and split diodes, and a limiting resistor, differently so that, for the sake of simplicity, one output of the control signal regulator is connected to the point e connection of the cathodes of the discharge diodes all control channels, the second output 2888394 It is intended to connect to the power source, and in each control channel, the connection point of the capacitor and the resistor of the RC chains is connected5 to the anode of the discharge diode and, via a separation diode, to the control electrode of the auxiliary thyristor whose anode is connected to the free output of the RG-chain resistor 10 and through the limiting resistor to the cathode of the charge diode, and the cathode together with the free output of the capacitor of the RC chain is intended to be connected to the control junction J5 of the corresponding thyristor of the converter; moreover, the anode of the charge diode is intended for connection to the anodes of the thyristors of the converter.  2. The device according to claim 1, wherein it is so that, for use in a three-phase single-half-cycle circuit, the second output of the control signal controller is connected to the junction point of the anodes of the charge diodes of all channels management 3. The device according to claim 1, characterized in that, for use in a single-phase circuit, it is equipped with a bridge diode rectifier, whose DC1 is directly connected to the second output of the control signal regulator, the other is intended to be connected to another load terminal, and the diagonal terminals of the alternating current are designed to be connected to the cathodes of the thyristors of the converter. FIG. one Compiled by V.Zhmurov Editor S, Patrusheva Tehred I.Popovich Proofreader L.Patay Order 7819/54 Edition 683Subscription VNIIPI USSR State Committee on cases of inventions and discoveries 113035. Moscow, Zh-35, Raushsk nab. 4/5 Production and printing company, Uzhgorod, st. Project, 4