SU1520641A1 - Voltage converter - Google Patents

Abstract

The invention relates to electrical engineering and can be used in secondary power supply and automation systems. The purpose of the invention is to increase efficiency. The converter contains a power transistor 1, covered by a positive feedback with the help of a current transformer 2. The turn-on winding 21 and the turn-off winding 10 of the current transformer 2, respectively, through the turn-on transistor 20 and the turn-off transistor 11 are connected to the supply terminals of the converters 8 and 23. To limit the duration of the open state of the turn-on transistor 20, the saturation choke 15 is used. The capacitor 7 forces the process of turning off the power transistor 1 when unlocking the switching transistor 11. 1 sludge.

Description

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The invention relates to electrical engineering and can be used in secondary power supply and automation systems.

The purpose of the invention is to increase efficiency.

The drawing shows a voltage converter ,,

The converter contains a power transistor 1 and a current transformer 2 The input of the power transistor is connected to the base winding 3 of the current transformer 2, the primary winding 4 of the current transformer is connected in series with the transistor 1 between the power terminals 5 and 6.

The capacitor 7 is connected by the first output to the first power output 8, and the second output to the first output of the first sensor 9 and through the switching winding 10 of the current transformer 2 to the collector of the switching transistor 11, the base of which is connected to the first terminal of the second resistor 12 and the collector of the second transistor 13 The base of which is connected through the first winding 14 of the droplets 15 of the terminal to the first outlet of the third resistor 16 and to the collector of the third transistor 17, the base of which is connected to the control terminal 18. The second winding of the 19th drossel 15 is connected to the base of the switching-on transistor 20 by the first pin. The collector of the transistor 20 is connected through the switching winding 21 of the current transformer 2 to the first output of the fourth resistor 22. The second output of the winding 19 of the leads 15, is connected to the emitters of the transistors 11, 13, 17 and 20 and to the power supply 8 The second terminals of the resistors 9, 12, 16 and 22 are connected to the second supply terminal 23..

The Converter operates as follows.

If at the input terminal 18 there is a high level control signal II TOj, the transistors 11 and 17 are turned on, and the transistors 1, 13 and 20. are turned off. All windings Drossel 15 de-energized. When the control signal is switched to a low level, the transistor 17 is closed. Through the windings 14 and 19 of the droplets 15, currents are unlocked that unlock the transistors 13 and 20. At the same time, the voltage on the winding 19 is limited by the direct voltage drop at the base-emitter junction of the transistor 20. The transformation factor of the chokes 15 is chosen so that We transform into the winding 14 and turned on in opposite direction with the power supply, did not cause the transistor 13 to be locked, and the transistor 11 is closed, and the transistor 20 is open for a short time determined by the time of the magnetization to saturate the core of the drosseels 15o A current pulse flowing across the winding 21 causes the power transistor 1 to turn on, which remains in the on state due to the positive feedback on the windings 3 and 4 of the current transformer 2 After switching the control signal on View 18 to a high level, transistor 17 opens, the voltage on the winding 14 of the droppers is 15 changes polarity, maintaining the base current of the transistor 13. due to the energy stored in the inductor 15, and thus forming a switching delay of the transistors 13, Pi, therefore, the power transistor History 1, Next, the processes in the circuit are repeated.

Transistors 17 and 13 together with resistors 16 and 12 amplify in power a control signal for switching off a transistor 11. Resistor 22 is designed to limit the pulse current of the winding 21 and transistor 20,

The capacitor 7 is designed to reliably turn off the power transistor 1 at the stage of its absorption. Resistor 9 sets the magnetization reversal current of current transformer 2.

The introduction of an additional winding of the choke switches and its connection to the base-emitter junction of the switching-on transistor allows increasing the efficiency of the magnet-transistor switch by reducing the power losses of the switching-on transistor.

Claims (1)

Invention Formula A voltage converter containing a power transistor connected by a base-emitter junction to the base winding of a current transformer and a collector emitter junction through the primary winding of a current transformer is connected to the power terminals of a converter that includes a transistor whose collector is sequentially five connected including a winding trans current transformer and the first resistor connected to the first power supply transformer, including a transistor, the collector of which through the current transformer connecting winding and the second resistor connected to the first power output of the converter, the inverting transistor and the third resistor, and the emitter of the switching and switching transistors connected to the second power output of the converter / characterized in that, in order to improve efficiency, a control trajectory is introduced ican, saturation choke capacitor and the fourth resistor, wherein the switching-off of the transistor base connected neposredstven2ib4G6 but with the collector the inverter of the skinny transistor and through the third resistor - with the first power output of the conversion f. The inverter transistor base through the first winding of the saturation throttles is connected to the collector of the control transistor connected via the fourth resistor to the first power supply terminal of the converter, the second windings of the saturation throttles are connected between the base and the emitter of the starting transistor, the condenser is connected in parallel to the circuit, 15 consisting of a turning off transistor and a turning off winding of a current transformer, and the emitters of the controlling and inverting transistors are connected to the second supply terminal 20 converter.