SU411585A1 - - Google Patents

Description

one

Generators for controlling thyristors are known, comprising output terminals, input terminals and a capacitor and a choke connected thereto, a main and auxiliary trasistors and a transformer with a primary, secondary, control windings and a positive feedback winding. However, such generators are complex in their design. In addition, an increase in the switching frequency of the thyristors is hindered by the rear gentle front of the generated pulses, due to which the science between the pulses can be reduced to zero.

The proposed generator differs from the known ones in that the primary winding of the transformer is connected between the capacitor and the choke, the secondary winding through a capacitor is connected to the output terminals shunted by the emitter-collector junction of the main transistor, the control junction of which is connected to the positive feedback winding. The primary and secondary windings of the transformer are connected in opposite directions, and its control winding is shunted by an emitter-collector junction of the additional transistor.

Such an embodiment of the generator makes it possible to simplify its circuit, increase reliability in operation, and improve the shape of the generated pulses.

FIG. 1 shows the scheme of the described generator; in fig. 2 is a graph of the output pulses of the generator.

When the power supply is connected to the input terminals 1 and 2, the core of the transformer 3 is re-magnetized along the primary winding 4 B of one of the directions. The capacitor 5 is charged in this case, and the main transistor 6 by the positive feedback winding 7 is kept in the closed state. At the output terminals 8 and 9, there is a sum of voltages on the capacitor 5 and the secondary winding 10 of the transformer 3. Form

the voltage at load 11 is close to optimal (see fig. 2). After remagnetization of the core to the saturation state due to the windings 10 and 7 of the transformer, transistor 6 opens like an avalanche, shunts

the load And connects the winding 10 to the capacitor 5. The current in the winding 4 is limited by the choke 12 and the magnetizing force in the core of the transformer 3 is generated mainly by the current in the winding 10.

The core is shifted to the opposite saturation state, the capacitor 5 is partially discharged, and when the transformer core reaches a new saturation state, the transistor 6 closes. Cycle

remastering is repeated.

Thus, at the output of the generator, control pulses appear, whose shape is close to optimal. To control the duty cycle of the output pulses, a control winding 13 of the transformer is provided, which is shunted by an additional transistor 14, operating in a linear mode when the control signal is applied to terminals 15 and 16.

High reliability and power of the generator is achieved by the fact that transistor 6 is not connected in series with the load circuit, but is used only to remagnetize the core of the transformer practically at idle when the load is disconnected.

Subject invention

A generator for controlling the thyristors, containing output terminals, input terminals and a capacitor connected to them and

choke, primary and secondary transistors and a transformer with a primary, secondary, control windings and a positive feedback winding are also distinguished by the fact that, in order to simplify, increase reliability and improve the shape of the generated pulses, the primary winding of the transformer is connected between the capacitor and choke, secondary winding through

the capacitor is connected to the output terminals that are shunted by the emitter-collector junction of the main transistor, the control junction of which is connected to the positive feedback winding, the primary and secondary windings of the transformer are connected in opposite directions, and its control winding is bypassed by the emitter-collector junction of the additional transistor.

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