SU1480053A1 - Controller of two anti-parallel thyristors - Google Patents

Abstract

The invention relates to electrical engineering and can be applied to thyristor devices connected in a counter-parallel circuit to the load circuit. The aim of the invention is to reduce the power consumed by the device. When a constant voltage or pulses are applied to the control electrode of the thyristor 1, it opens, and a positive half-wave of the supply network flows through the load 3. At the same time, a current flows through the circuit. Diode 4 - Resistor 5 - Diode 14 - Capacitor 7. After the positive half-wave ends, a pulse is produced, which passes through the control electrode of the thyristor 2 and unlocks it. This process is repeated every period. 2 Il.

Description

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The invention relates to the field of electrical engineering and can be used in thyristor devices connected in a parallel-parallel circuit to the load circuit.

The aim of the invention is to reduce power consumption.

FIG. 1 shows a diagram of this device; in fig. 2 - time-sensitive voltage diagrams at the most important points of the circuit relative to point A.

A device for controlling anti-parallel connected thyristors 1 and 2 connected in series to load circuit 3 contains a diode 4 connected in series and a resistor 5, the free terminal of which is connected to the cathode of Zener diode 6, 20 whose anode is intended to be connected to one load terminal 3, for connecting to the other output of which the anode of diode 4 is designed, capacitor 7, one output of which is connected to 25, does not open transistor 12, will receive a single diode with anode of zener diode 6, a trap with an avalanche-like process, since

the waveguide ends, the passage through zero, a pulse is generated, which passes through the control electrode of the thyristor 2, opening it. This process is repeated every period. Let us consider in more detail how the thyristor control pulse 2 is generated. After the capacitor 7 charges until the voltage stabilizes the Zener diode 6, it keeps this voltage, since the diode 14 protects it from the discharge, and the transistor 8 is closed due to a large resistance of the resistor 10. After the positive half-wave ends on the 4 emitter of transistor 12 (point B, fig., 2) the voltage drops to zero, and the emitter of transistor 11 (point D) will have a capacitor charge voltage of 7 resulting in resis OR 10, baza- emitter of transistor 12 and resistor 13 flows a small current, which beginning asked to open the transistor 12, with poluchit- avalanche process, as

the waveguide ends, the passage through zero, a pulse is generated, which passes through the control electrode of the thyristor 2, opening it. This process is repeated every period. Let us consider in more detail how the thyristor control pulse 2 is generated. After the capacitor 7 charges until the voltage stabilizes the Zener diode 6, it keeps this voltage, since the diode 14 protects it from the discharge, and the transistor 8 is closed due to a large resistance of the resistor 10. After the positive half-wave ends on the 4 emitter of transistor 12 (point B, fig., 2) the voltage drops to zero, and the emitter of transistor 11 (point D) will have a capacitor charge voltage of 7 resulting in resis OR 10, baza- emitter of transistor 12 and resistor 13 flows a small current, which beginning

Sistor 8, the collector of which is connected to another capacitor 7 lead, the emitter is connected to one pin of a resistor 9, the other pin of which is intended to be connected to the control electrode of the thyristor 2, and the base is connected to one pin of a resistor 10, the other lead of which is connected to the collector transistor 8 and the emitter of transistor 11, the collector of which is connected to the bases of transistors 8 and 12, the base of transistor 11 is connected to the collector of transistor 12, the emitter of which is connected to one output of resistor 13 and the anode of diode 14, another output of resistor 13 the cathode of the diode 14 are connected to one and the other terminals of the capacitor 7, respectively, the anode of the diode 14 is also connected to the zener-cathode 6 and the gate electrode of the thyristor 1 is designed for connection to the output of the source control signal.

The device works as follows.

When a constant voltage or pulses are applied to the control electrode of the thyristor 1, it opens and a positive half-wave current of the supply network flows through the load 3, while the current flows through the circuit: diode 4, resistor 5, diode 14 and capacitor 7. After. how positive for

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the collector current of transistor 12 goes through the base-emitter of transistor 11, and the collector current of transistor 11 doesn’t cut the base-emitter of transistor 12, opening it further. Both transistors open and remain in this state while power is present. Since the collector of transistor 11 is also connected to 5 base of transistor 8, it also opens and capacitor 7 is discharged through transistor 8, resistor 9 and thyristor control electrode 2 point D) which opens and passes a negative half-wave of current into the load.

Thus, this device allows the formation of control pulses of the second thyristor by taking power from its power circuit, increasing the noise immunity, since the thyristors are opened when the current passes through zero. The advantage is also the possibility of using a single power source to control several circuits.

Claims (1)

Invention Formula A device for controlling two anti-parallel-connected thyristors connected in series to a load circuit comprising a diode whose anode is intended to be connected to one load terminal, the other output of which is connected to the connection point of the anode of the first thyristor and the cathode of the second thyristor, the cathode of the diode is connected to one output the first resistor, the other output of which is connected to the cathode of the Zener diode, the anode of which is intended to be connected to another load terminal, the capacitor, one output of which is connected the anode of the Zener diode and the other is connected with its cathode, a second resistor, one output of which is intended to be connected to the control electrode of the second thyristor, and the control electrode of the first thyristor is intended to be connected to the output of the control signal source, so that that, in order to reduce power consumption, a direct-conducting transistor, the first and second reverse-conducting transistors, the third and fourth resistors, and an additional diode are introduced, with the anode of the additional diode connected to The Zener diode, the emitter of the first reverse transistor and one terminal of the third resistor, the cathode of the additional diode is connected to another terminal of the capacitor, the collector of the second reverse transistor transistor, one terminal of the fourth resistor and the emitter of the direct transistor, the collector of which is connected to the base, and the base is with collector of the first reverse transistor transistor; the base of the first reverse conduction transistor is also connected to the base of the second reverse transistor transistor and another output of the fourth resistor, the emitter of the second reverse transistor transistor is connected to another output of the second resistor, and the other output of the third resistor is connected to the Zener diode anode.