SU860311A2 - Magnetic transistor dc switch - Google Patents

Description

i

The invention relates to electrical engineering relating to the problems of the conversion and regulation of electrical energy.

According to the main author. St. 746931 is known for a magnetically-transistor switch of direct current, containing power transistors, a current transformer with primary and secondary windings, ... the primary winding being removed from the midpoint, connected to the output terminal of the switch, and the extreme leads of this winding The emitter-collector sections of the corresponding power transistors are connected to the input terminal of the switch, an auxiliary transistor connected to one of the power transistors according to the composite transistor circuit, the base of the auxiliary transistor 20 is connected to the control terminal of the key, in addition, the secondary winding is made with a tap from the midpoint, its extreme leads, respectively, ° - are connected to the bases of the power transistors, - and the electrode of the auxiliary transistor is connected to the tap from the middle

points d-i.

The disadvantage of the known device is a relatively low gain ratio of 30.

because the converter circuit in the open state needs a constant signal to be unlocked.

The purpose of the invention is to improve the energy performance.

This goal is achieved by the fact that two diodes and two additional transformer windings are introduced into a direct current magnet-transistor KJB04, one end of which is connected respectively to the ends of the secondary winding of the transformer, and the others through diodes are connected and connected to the auxiliary transistor control input. .

The drawing shows a circuit diagram of a magneto-transistor dc switch.

Claims (2)

The device contains the power transistors 1 and 2, the auxiliary transistor 3, the current transformer 4 with the primary windings 5 and 6 and the secondary windings 7 and 8, the load 9 through the converter is connected to the power source 10 (Iptz-g.) Control circuit of the auxiliary transistor 3 through diodes 11 and 12 is connected to the additional windings 13 and 14. To the "auxiliary transistor 1 run", the control output of control unit 15 {Y9) is connected; The Converter operates as follows. When a signal is received from the control device 15 with a plus on the base of the auxiliary transistor 3, this transistor opens. Due to the dissimilarity of the characteristics, a slightly larger current will flow through transistor 1 than through the transistor 1 2. As a consequence, a greater current will flow through the winding 5 than through the winding 6. The current difference is transformed into the secondary winding 7 (the polarity of the voltage is shown in the drawing), providing even greater unlocking of the transistor 1 and locking of the transistor 2, the unlocking signal from the device 15 control after starting the device can be disconnected, since the unlocking of the auxiliary transistor 3 is carried out through additional diodes 11 and 12 from the windings 13 and 14, partially combined with secondary windings 7 and 8, from which The torsional displacement of the power transistors 2 and 1, the voltage on the windings 13 and 14 exceeds the voltage of the windings 7 and 8 by the amount of voltage drop on the additional diodes 11 and 12. After magnetizing the core of the transformer 4, the power transistor 1 closes. On the windings 7, 8, 13 and 14, a self-induction EMF is induced, which provides unlocking of the auxiliary transistor 3, active locking of the power transistor 1 and unlocking of the power transistor 2. When switching the power transistors 1 and 2, the auxiliary transistor 3 does not have time to close and -this resorption minority carriers in its base, Therefore, when switching transistors 1 and 2 there is no voltage on -Increase silovyk RE rows of transistors, t, -e. there are no dynamic losses. In the following, the processes are repeated. To turn off the device, it is enough to send a signal from the control device 15 to block the auxiliary transistor 3, the duration of which is determined by the closing time of this transistor. To avoid self-starting of the device, it is sufficient to bridge the base-emitter transitions of transistors with 1-3 resistors or to send a weak locking signal from the control device 15. Without changing the essence of the invention, the primary windings of the transformer can be included in any suitable places (for example, in the collectors of power transistors), secondary windings 7 and 8 can be used as power and auxiliary transistors of different conductivity types. It is also possible to connect additional windings to the input of the auxiliary transistor across the bridge straightener. Increasing the gain factor makes it possible to drastically simplify the design of the control device 15, since it requires only narrow control pulses. Claims of the invention Magnetic transistor dc switch according to avtsev, no. 746931, characterized in that, in order to improve the energy performance, two diodes and two additional transformer windings are inserted into it, one of the ends of which is connected respectively to the ends of the transformer secondary winding and the others, via diodes, are combined and connected to the control input of the auxiliary transistor. Sources of information taken into account in examination 1, USSR Copyright Certificate No. 746931 for Application No. 1907504 / 24-07, Cl, H 03 K 17/60, 22,02,73,