SU1501227A1 - Device for controlling thyristors of energy converter - Google Patents

Abstract

The invention relates to electrical engineering and can be used to control the thyristors of various converters. The aim of the invention is to improve the noise immunity of the device. The use of an additional power source 1 and two transistors 4 and 5 allows galvanically separating the negative leads of the control signal generator 2 and the output pulse generator 13, which eliminates the possibility of interference from the power section into the driver 2. In addition, protection of the driver 13 from false alarms is provided that the diode 15 at the moments of absence of control signals creates a reverse voltage equal to the difference between the voltages of the main 16 and additional 1 power sources. In this case, the transistor 14 will be reliably locked until the amplitude of the impulse noise arising at the moment of operation of a certain thyristor exceeds this voltage difference. Thus, the device provides reliable protection against interference from both the driver 2 of the control signal and the driver 13 of the output pulses. 2 Il.

Description

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From (Receiver C TIOSIT to the luu KTpo technique and we can, if you want, control the thyristor of the various types of settings.

The purpose of the invention is fiOBt.ii if: the CIR of noise immunity is arranged, I on.

Figure 1 shows an electrical diagram of a control unit with a driver using a capacitor discharge to the primary winding of a liM-pulse transformer via a transistor switch; figure 2 - diagram of the device with a pulse shaper in the form of blocking generators.

The device for controlling the thyristors of the energy converter contains a power source 1, a control signal shaper 2 with stabilization unit 3, the first 4 and second 5 transistors with resistors 6 and 7 in the collector circuits, a voltage divider 8, a current limiting chain of parallel-connected resistors 9 and a capacitor 10, a diode 11 and a resistor 12, as well as an output pulse shaper 13 on a transistor switch 14, the emitter circuit of which includes a diode 15 and a power source 16. The shaper's output pulse is fed to the control element Trodena co otvetstvuyuscheg of power thyristor converters.

The device works as follows.

In the absence of control signals at the output of the driver 2, the transistors 4 and 5 are in the locked state. At the collector of transistor 5 there is a negative potential - Un. which through a chain of resistor 9 and capacitor 10 and diode 11 is fed to the anode of diode 15. At the cathode of this diode there is always a negative potential - Un. In the case when the voltage source, power 1 exceeds the voltage of source 16, diode 14 is shifted in the opposite direction by the difference in voltage Ufij-Uni. The choice of the magnitude of this difference, greater than the maximum possible amplitude of voltage surges occurring on the negative bus of the source 16 at the time of operation of the power thyristor, ensures high noise immunity of the output pulse driver 13. For example, with the parameters Ur 25 V and pg

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 l.-j The lipus level of interference, with KOTOi CiM, reliable operation of persons is maintained} the shape of the mold can reach 100 V.

Shaper 2 may contain any analog and digital integrated circuits and is designed to provide a predetermined algorithm for the operation of a particular conversion unit, which is not shown in Figures 1 and 2 for simplicity. The control signal appearing at the corresponding output of the driver 2 opens the transistor 4, which through the voltage divider 8 delivers a negative potential to the base of the transistor 5, ensuring that it is turned on. In this case, the reverse voltage is removed from the diode 15, and the base of the transistor 14 is applied: put a potential that leads to its inclusion.

The operation of the transistor switch 14 leads to the discharge of the pre-charged capacitor of the driver 13 through the primary winding of the pulse transformer in the circuit of FIG. 1 and to the development of blocking-process in the circuit of FIG. 2. In both cases, the output of the imaging unit 13 produces a control pulse of a certain amplitude and duration, which is fed to the control transition of the corresponding power thyristor.

Thus, the proposed yQT-device provides reliable protection against impulse noise and protection of the control unit by galvanic opening of the minus buses of two low-voltage power sources, and the output driver itself, by creating a reverse voltage on the diode connected to the transistor emitter circuit key. The voltage range of this voltage is chosen above the level of the maximum possible 1 gmp interference.

Claims (1)

Invention Formula A device for controlling the thyristors of the energy converter, comprising a main power source, a control signal driver, a current-limiting circuit and an output pulse driver, made on a transistor whose collector is connected to one primary terminal -In -Uffi (pus.2