SU1023622A1 - Thyristorized converter control device - Google Patents

Abstract

A DEVICE FOR CONTROLLING A THIRISTOR TRANSMITTER, Containing successively INCLUDED first resistor, second and first base of a single junction transistor and. Primary winding of a pulse transformer, as well as a second resistor, variable resistor and capacitor, with the input poles of the first and second resistors combined and the same as the resistors positive to the 4th pole of the source of synchronizing voltage, the combined output poles of the capacitor and the primary "" g-; t;: m7,: cb. gx;,.:,; ", winding of the pulse tra The transformer is intended to be connected to the negative pole of the indicated source, and the secondary winding of the pulse transformer is intended to be connected to the control electrode of the thyristor, characterized in that in order to stabilize the set value of the voltage on the load during voltage fluctuations of the network voltage, it is equipped with a sequence of the included third resistor, the first Zener diode and the first diode, the second Zener diode in series, the fourth resistor and the second diode, and § also there are a resistor, the cathode of the first diode, the anode of the second di (A and the first pole of the first resistor are connected to the negative pole of the indicated source, the variable resistor is connected in series with the first and third resistors, the input pole of the capacitor is connected to the midpoint of the variable resistor and the single junction emitter transistor, the cathode of the second disd is connected w: U9 to the first base, and the second pole of the nth resistor is connected to the second base of the unijunction transistor. 3 ISD Yu

Description

The invention relates to the field of electrical engineering, namely to devices for controlling a static converter to obtain the required value of the output parameter, made on semiconductor devices with a control electrode, k can be used to change and stabilize the voltage, hence the power required by the active or an active-inductive load from an alternating voltage power source, and an estate to control the voltage on the coil of the vibrobunker electromagnet, electric heaters (pipes Active and inductive or active load of the control circuit. A device containing a thyristor connected via a load to a power source, in parallel to which a pulse generator is connected, which consists of parallel-connected serial RC circuit and H0: The RD circuit contains a damping resistor, the transition base 2 is the base 1 of a diode transistor and a constant resistor, the thyristor control circuit is connected in parallel with the KOTopoiv, the cathode of which is connected to the common point of the o-negative power supply and output terminal ensatora Re-chain, and the total point of the latter is connected to the emitter of transistor 1, however, such a device: has a limited range of applications because of the galvanic connection between the power source and the control circuit and the thyristor changes the set value of the load voltage x at ksytebani voltage. network. The closest to the technical entity proposed is a device for controlling a thyristor converter, containing in series the first resistor, the second and the first base of the single junction transistor and the primary winding of the pulse transformer, as well as the second resistor, variable resistor and capacitor, and the input of the first and the second resistors are combined and intended to be connected to the positive pole of the source of the synchronizing voltage, the combined output poles of the terminal Satoru and the primary winding of pulse Transfrm Matora intended for connection to the negative pole of said source, and the secondary winding of the pulse transformer is designed for connection to the control electrode of the thyristor 2J. A disadvantage of this device is the limited range of adjustment of the set value of the voltage across the load during fluctuations in the network voltage. The purpose of the invention is to increase the stability of the set value of the voltage on the load during fluctuations in network voltage. The goal is achieved in that the device for controlling the thyristor converter is equipped with a series-connected third resistor, a first zener diode and a first diode, a series-connected second zener diode, a fourth resistor and a second diode, and a fifth resistor, the cathode of the first diode, the anode of the second diode and The first pole of the first resistor is connected to the negative pole of the indicated source, the variable resistor is connected in series, with the first and third resistors, the input pole to ndensatora connected to an intermediate point of the variable resistor and the emitter of unijunction transistor, the second diode cathode is connected to the first base and the second terminal of the fifth rezicTopd - a second base unijunction transistor. FIG. 1 shows a circuit diagram of the device; in fig. 2 - temporary voltage diaphragms in the output winding of the pulse transformer, at the thyristor anode and load; in fig. 3 - change of the half-wave voltage at the load when the mains voltage changes by + 10%. The device for controlling the thyristor converter contains a second DC resistor 1, a variable resistor 2, a third DC resistor 3, the first Zener diode 4, the first diode 5, the load 6, the second Zener diode 7, the capacitor 8.,. the fourth constant resistor 9, the primary winding of the pulse transformer 10, the secondary winding of the pulse transformer 11, the unijunction transistor 12, the second diode 13, the pulse transformer 14, the first constant resistor 15, the thyristor 16, the fifth constant resistor 17. The device contains a series circuit consisting of resistors 1-3, zener diode 4 and diode 5 connected in opposite, load 6 connected through thyristor 16 to an alternating voltage power source; resistor 15, transition base 2 base 1; transistor 12 and diode 13, in parallel with which the input winding 10 of pulse transformer 14 is connected, the output of which is connected to the negative terminal of the source of the rectified voltage Cathode voltage of diode 5, or capacitor 8 anode, diode 13 and resistor 7 output, the input connected to base 2 transistor 12; Zener diode 7 and resistor 9, the output of which is connected to the base 1 of the transistor. 12, and the cathode of the Zener diode 7 - to the common point of resistors 2 and 3,

The middle terminal of the resistor 2 is connected to the input of the capacitor 8 and c. . the emitter of transistor 12, and the inputs of resistors 1 and 15 are connected to the positive terminal of the power source. rectified voltage. The output winding 11 is connected to the thyristor control circuit 16, so that the cathode of the latter is connected to the output of the winding 11.

The device works as follows.

When the power source is turned on, the load is supplied with a load of 6 alternating voltage of 50 Hz, 220 V at the transition of the anode - cathode of the thyristor 16. At the same time, the lower half-wave rectified voltage goes through the resistors 1 and 2 to the code (capacitor 8; resistors 1, 2 and 9 on; zener diode7, resistors 1-3 on stabilizer: 4; resistor 15 on base 2 junction -. base 1 of transistor 12 and on resistor 17, set voltage drop on junction of base 2 base 1 of transistor 12 and input winding 10 of transformer 14.

With a constant resistance of the variable resistor 2, the capacitor 8 is charged and the discharge across the zener diode 7 and resistor 9 and the resistor 3 in part through the circuit - zener diode .4 and diode 5, since the resistance of the resistor 3 is greater than the resistance of the resistor 9.,

When the resistance of a variable resistor 2 in the capacitor charge circuit decreases, the voltage drops across resistors 2, 3, and 9, zener diodes 4 and 7, and the voltage drops across resistor 1 and emitter junction base 2. and emitter – base 1 of transistor 12.

The increase in the amplitude of the voltage on the capacitor 8, therefore, on the transition emitter -. The base 1 of the transistor 12 occurs to the amplitude of the turn-on voltage of the transistor 12. When opening the transistor 12, the resistance between the emitter and the base 1 decreases sharply, at which the transistor 12 opens. When opening

the transistor 12 changes the polarity on the capacitor 8 and discharges the latter through the transition emitter-base 1 of the transistor 12 and the input winding 10 of the pulse transformer 10, while the magnitude of the discharge current through the zener diodes 4 and 7 decreases.

As the capacitor B is discharged, the amplitude of the discharge current decreases, and therefore the voltage across the emitter – base 1 of transistor 12. When the transistor 12 is open and the amplitude of the discharge current of capacitor 8 decreases, the amplitude of the current passing from the power source through the resistor 1 and 2, respectively: the total amplitude of the current passing through is accordingly increased;

0 transition emitter - base 1 transistor 12.

Since the total amplitude of the current passing through the junction emitting base 1 is greater than the amplitude of the switching current, the transistor 12 remains oTKpii5 until the end of the positive over-voltage condition of the network.

Opening transistor 12 reduces the resistance of the base 2 - base 1 transition, increases the amplitude of the current passing through the resistor 15, and therefore the winding 10 of the transformer 14. When the amplitude of the network voltage decreases to a positive half-period.

5 of the minimum value, the transistor 12 is closed.

In the future, at a constant value of the resistance of the variable resistor 2 in each of the positive

The 0 half-period of the network voltage, the process of charging and discharging the capacitor 8, and therefore switching the transistor 12, is similarly repeated, with the amplitude of the voltage on the capacitor 8 being out of phase with respect to the phase amplitude of the voltage on the anode of the thyristor 16 by .grad. .

Thus, in the output winding 11 of the transformer 14, the resulting pulse with a steep leading edge

0 (Fig. 2a) arises in the control circuit of the thyristor 16 in the period of zero crossing and initial growth in the positive half-period of the sinusoidal voltage of the network, ajar

5 while the thyristor 16 (Fig. 2b).

When current flows at load 6, a voltage drop is formed: (Fig. 2c) equal to the difference between: waiting for the network voltage and voltage drop at the open thyristor 16.

In the negative half-period of the network voltage, the transistor 12, therefore, the thyristor 16 also remains closed. When changing polarity

5 inactivity (in the positive half period) at a constant value of the resistance of the variable resistor 2, the switching process of the transistor 12 and the thyristor 16 likewise repeats. ;

When the resistance of the variable resistor 2 decreases in the emitter circuit of the transistor 12 of the minimum value, a smooth formation occurs, increasing in amplitude, increasing

Reducing the number and decreasing the delay angle of the control pulses of the thyristor 16 to the maximum value (fig; 3g), at the same time, the voltage drop across the anode-cathode transition of the thyristor 16 decreases to the minimum value in the positive half-period (fig. 2n). wherein a gradual increase in the voltage drop across the load 6 to the maximum value occurs (Fig. 2e).

To reduce the voltage setpoint, i.e. voltage stabilization at load 6 when the mains voltage changes by + 10% and with a constant value of resistance - variable resistor 2, the RD-en is included, consisting of resistor 3, zener diode 4 and diode 5. Turning on diode 5 improves the temperature mode zener diode and voltage load stabilization.

The inclusion of the RD-cshg increases the voltage amplitude on the capacitor 8, and therefore on the peripads. emitter - base 1 and emitter - base 2, at which the inclusion occurs. the transistor / 12, while decreasing the opening delay angle of the thyristor 16, i.e. the voltage drop across the load 6 increases from 0 to 5 ... 25 V, depending on the variation of the parameters of the transistor 12 and the thyristor 16.

In order to increase the opening delay angle of the thyristor 16, therefore, and to reduce the fall on the load band 6 at the same maximum value of the variable resistor 2, an additional RD circuit is included, consisting of zener diode 7 and resistor 9.

The inclusion of an additional RD circuit through the winding 10 parallel to the base of the RO circuit reduces the sultarial resistance of the main RD circuit, therefore, the amplitude of the voltage across the capacitor, while increasing the opening delay angle of the thyristor 6 to the maximum value. The presence of an additional RD circuit improves voltage stabilization at voltages at loads up to 30 V.

By turning on resistor 17 parallel to base 2 - base 1 of transistor 12 and winding 10, the optimum operating mode of transistor 12 when the voltage on capacitor 8 changes from minimum to maximum is set, the voltage is stabilized at a load of 80-100 V.

The stabilization of the voltage setpoint at load 6 with a constant resistance of the variable resistor 2 when the voltage of the network changes by 10% is as follows.

When network voltage decreases

-10% decrease by

the input of the voltage generator, therefore, on the zener diodes 4 and 7, at which the resistance of the latter increases, while the current through the RO circuit decreases.

When the current passing through the RD-circuits decreases, the voltage on the capacitor 8 increases, the set amplitude and shift angle of the pulses in the thyristor control circuit 16 are maintained within certain limits, hence the drop in the set value of the voltage on the load 6. Similarly The process of stabilization of the set value of the voltage on the load 6 takes place at a constant resistance of the variable resistor 2 with an increase in the network voltage to

 in which there is a decrease in the resistance of the RD-chains, hence an increase in the current through them.

Decrease of charge

the current of the capacitor 8 leads to a decrease in the shear angle of the control pulses, increasing the voltage drop across tyr, which occurs, a slight decrease in the voltage drop across the load 6.

FIG. Figure 3 shows the variation of the half-wave voltage at the load when the network voltage is changed by ± 10%.

From FIG. 3, it follows that the stabilization of the set value of one-. Loop voltage on the load occurs in the range of 10 ... 100 bb and depending on the spread of the parameters of the thyristors and transistors is located in the region shown in (shaded) in fig. 3

With a full-wave voltage on a load connected, for example, through a TCGY triac or through two KU 202 thyristors counter-parallel, the voltage on the load stabilizes within 15 ... 180 V with a voltage of 220 V + 10%.

Thus, the inclusion of RD-circuits and an additional resistor 17 reduces the change in the set value on the load when the network voltage is changed by ± 10%, therefore, expands the applicability of the proposed device.

O / ffSJ

Claims (1)

A device for controlling a thyristor converter, containing the first resistor, the second and first ba * e of a single-junction transistor and the primary winding of a pulse transformer, as well as a second resistor, a variable resistor and a capacitor, the input poles of the first and second resistors combined and connected for connection to the positive pole of the source of synchronizing voltage, the combined output poles of the capacitor and the primary winding of a pulse transformer are designed for connecting to the negative pole of the specified source, and the secondary winding of the pulse transformer is designed to connect to the thyristor control electrode, characterized in that, in order to stabilize the set voltage value at the load during mains voltage fluctuations, it is equipped with a third resistor, a first zener diode and a first a diode connected in series by a second zener diode, a fourth resistor and a second diode, as well as a fifth resistor, the cathode of the first the iodine, the anode of the second diode, and the first pole of the fifth resistor are connected to the negative pole of the indicated source, the variable resistor is connected in series about the first and third resistors, the input 2 pole of the capacitor is connected to the midpoint of the variable resistor and emitter of the single-junction transistor, the cathode of the second connected to the first base, and the second pole of the fifth resistor to the second base of a single-junction transistor.