SU661720A1 - Switch-type generator - Google Patents

Description

(54) KEYEVOR1 GENER.LTOR

one

The invention relates to the field of pulse -1 () technology and can be used to generate quasi-acoustic frequency oscillations sent to the power cable line when searching for a cable damage site by the induction method.

Known generators of quasi-rectangular oscillations, containing transistors connected in a bridge circuit with semi-dependent excitation, have a primary winding of the transformer in the bridge diagonal; resistor 1.

The disadvantage of this generator is the impossibility of operating in irikih ranges of change in the frequency of the output oscillations.

In addition, key generators are known that contain a bridge on transistors, high voltage; 1 transformer, a control voltage source, the outputs of which through thyristors are connected to the corresponding transistors, and forming unit 2.

A disadvantage of this device is that it can operate only in relatively narrow ranges of change in the frequency of output oscillations and load currents.

The purpose of the invention is to expand the ranges of change in the frequency of the output oscillations and the load current.

This circuit ..: is achieved by the fact that in a key generator containing a bridge on transistors with semi-dependent excitation, an output transformer whose primary winding is included in one bridge diagonal, a power source included in another bridge diagonal, a control voltage source, the outputs of which through the thyristors are connected to the bases of the first and second transistors of the bridge, forming the unit, the outputs of which are connected to the corresponding electrodes of the thyristors, and the diodes, the first and second of which are included anti-parallel -tr temu bridge and fourth transistors, respectively, one of terminals v.chodnyh forming unit is connected to the emitters of the first and second transistors, the collectors of which

through the counter-included third and fourth diodes are connected to another input terminal of the forming unit.

. The invention is explained by cherzhi. FIG. Figure 1 shows a graphic element; an electric electrical circuit of a key generator, the forming circuit of which is made on a transformer: in FIG. 2 - the principle electrical circuit of the generator, the forming circuit of which is made on LEDs.

The key generator of the pulses contains a bridge on transistors 1, 2, 3, 4 with a semi-dependent driver. A primary winding 5 of the output transformer b is included in one diagonal of the bridge, a power supply 7 is included in the other diagonal of the bridge. The phase-out outputs of the control source are connected through thyristors 9 and 10 to the bases of transistor 1 and transistor 2 -blost. U1V; O1Ts e electrodes of tirp.stor 9 and iO are connected to you {yugm.iruyuschego current P. Vstropnaye parallel to tdm.istorkh3 switched on diode 12. anti-pg. i 1 is connected to .iTTe: 5a .. ;; i transistors i and 2. whose collectors are counter-on. valuable disla M and 15 are connected with another deceleration of the current P. P. To the auto-winding of the winding Formagor 6, the load 6 is connected.

Vypolno; -: s block P may be different. M and is not an essential sign of this (ic-attachment.

Block I I - iij / .- eT is completed, for example. on the impulse goaisgsrmatore 17 big. one). pepsy obm ;; hk which zkl; oche; and between the connecting point;: neni tra:; 3 1CT (; ditch I, 2 and the connecting point of the dozens 14,15, and the secondary parts are connected to the inputs of the shooting gallery ::: tori 9 and 10. Stabilitron I is limited, - :: 1p same: and; e at the input of block 1 1.

The block 11 can be executed, for example, on the earthwise connected light emitting diodes 19. 2). connected in parallel to the resistor 21 -1 optically coupled to the thyristor. 9, 10 which are light-guided (Fig. 2).

The key generator works as follows .m; ::.

Let the power supply open, for example, t; fistor 9 (the starting impulse comes from the control voltage source 8: and transistors .1 and 3 bridges. When this is, in the bridge diagonal, a current flows from the winding 5 (from left to right for the circuit Fig. 1) and in the load 16, for example, a positive half-w of the output voltage is generated.

When the polarity is changed, the voltage of the control voltage source. 8 to the input junction of the trans.; The source 1 and to the thyristor 9 is applied a blocking force L1e. As soon as transistor 1 is locked, the inductive current flowing through the output

the diagonal of the bridge closes through diode 13 and transistor 3. Unlocking diode 13 leads to almost zero voltage on the output; the diagonal of the bridge. Accordingly, to zero, the voltage on all windings is gag. This is the output of the input transformer b, including the winding in the base circuit of transistor 3. The process of the output of transistor 3 from saturation starts at this moment. The transistor 3 is closed and the inductive current flowing into the output of the D | ago Ali bridge closes through the diode 13, the internal resistance sources 7, the input of the shaping unit I and the diode 15. At the same time, depending on the structure of the forming

The unit excites the primary winding of the transformer 17 or a chain of LEDs 19, 20 and a trigger pulse is applied to the input of each thyristor.

Thyristor 9 is under the influence of negative voltage source 8

and does not respond to the trigger pulse, and the thyristor 10 is turned on and provides the trigger current to the base of the transistor 2. A simultaneous trigger pulse is generated in the base circuit

5 transistor 4, since after turning off transistor 3 and turning on diode 5, winding 5 turns out to be the inverse voltage of the field (for the circuit on lamp 1 plus on the right and minus on the left). Transistors 2 and 4 open. the inversion of the current in the output of the bridge diagonal occurs, and until the next polarity change of the voltage of the control voltage source of 8 hours to the load, the half-wave output voltage of the voltage acts negatively.

After the next change of the polarity of the control voltage source 8, the processes in the key generator, according to the foregoing, occur in the following sequence.

To the thyristor 10 and the input of the transistor 2

0 a locking clamp is applied. Transistor 2 is locked, the inductive current flowing from the output diagonal of the bridge from right to left opens diode 12, the voltage on the winding 5 drops almost to zero and, accordingly, the voltage on the base winding of the transistor 4. The transistor 4 is closed; Open 14 opens. A voltage is applied to the winding 5. A base voltage is formed on the base of the winding of transistor 3. At the same time, JQ inductive current flows in the bridge diagonal through diodes 12 and 4, excites the primary winding of the transformer 17 or LEDs 19, 20 of the forming unit 11, which leads to the turning on of the thyristor 9 and the supply of unlocking current 5 to the base of trans1 stor 1. Transistors. 1 and 3 open and follow. when the polarity of the source 8 is changed, the positive half-wave will again act on the load 16.

Thus, o6pa: soM, the proposed solution in comparison with the well-known one allows the ranges of changes in the frequency of the output oscillations and the load current to be divided.

Claims (2)

1. USSR author's certificate 5,320,914, cl. H 03 K 3/20, 15.06.69. 2. Authors certificate of the USSR .Vo 522542, cl. H 03 K 3/00, 07.13.73. fail L