SU1398047A1 - Method of controlling transistorized d.c.-to-d.c. voltage converter - Google Patents

Abstract

The invention relates to electrical engineering. The goal is to increase reliability by eliminating current overloads. at. power transistor. A rectangular voltage is applied to the power transistor 1 of the device and the reference voltage is taken from the source of the reference voltage 5. The magnitude of the reference voltage varies in phase and is proportional in amplitude to change -. spun on the filter capacitor 4 with the conversion frequency. By choosing the nature of the change in the magnitude of the reference voltage, at the moment of switching, the current through the power transistor 1bsh is close to zero. In this case, the secondary winding of the transformer 2 is idling due to the locked state of the rectifying diode 3. 2il. from 9 (L

Description

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The invention relates to electrostatic and can be used in the sources of secondary power supply systems of radio engineering, automation and computer technology.

The purpose of the invention is to increase the reliability of a dc-to-constant transistor converter by eliminating an overcurrent of transistors over current at switching times.

FIG. 1 shows a variant of the electric circuit of a DC / DC transistor converter; in fig. 2.- time diagrams: a - characterizes the change in voltage on the filter capacitor, S is the change in the magnitude of this voltage jkoHHoro, which should ifMeTb place to eliminate the over-current in the power transistor (relative magnitude of the amplitudes a and & Corresponds to the ratio of transformer

mation of the transformer of the converter) 25 stabilization of the equivalent resistance - the behavior of the current I through the key elements without applying the proposed method, Z - under the conditions of its application.

the emitter circuit of the power transistor 1 and, thereby, eliminates current overload. Moreover, the choice of the nature of the change in the magnitude of the reference transistor converter of the potential voltage (i.e.

a constant voltage to a constant (fig. 1) - contains a power transistor 1 ;, connected according to the emitter p | otoritor circuit, with the transformer 2 in the emitter circuit, the secondary winding of the transformer 2 is connected through you Cr 3 and filtering the condensation - lb4. with output terminals, and the control input of the power transistor-trd 1 is supplied to the control line, the head voltage, the amplitude of which is proportional to the reference voltage removed from the source 5 of the reference voltage.

The control method of the transistor converter is implemented in the following manner.

50

When a positive voltage is supplied to the control input of the power transistor 1, the power transistor 1 is opened and the primary winding of the transformer 2 is supplied with a voltage whose amplitude is proportional to the reference voltage, since

transistor 1 operates in the active re-, rc transformer, the primary winding

burn me (without going to tax saturation). However, a voltage surge at the control input of the power transistor 1 may cause an overcurrent (Fig. 2 &).

which is included in the emitter circuit of the power (Transistor, characterized in that, with a workshop, reliability is improved by eliminating

since in the previous period of operation of the converter (in the closed state of the power transistor 1), the filter capacitor has time to discharge. When the input rectangular voltage varies according to the proposed control method (Fig. 2B), the control voltage at the input of the power transistor 1 varies in proportion to the amplitude and phase with the voltage across the filter capacitor 4 (while maintaining the average the value of the constant component of the reference voltage at a constant level), overload current in the power transistor 1 is eliminated (Fig. 2 g).

Thus, as can be seen from FIG. 2q-Z, the change in the magnitude of the reference voltage in the phase and in proportion to the amplitude of the voltage change on the filter capacitor 4 with the conversion frequency contributes

the emitter circuit of the power transistor 1 and, thereby, eliminates current overload. Moreover, the choice of the nature of the change in the value of the standard5 0

five

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proportionality) it is possible to achieve that directly at the moment of switching the current through transistor 1 is close to zero, while the secondary winding of transformer 2 seems to be idling due to the locked state of the rectifier 3.

Thus, the application of the proposed method contributes to the elimination of current overloads of the power transistor, which increases the reliability of the voltage converter.

Claims (1)

Invention Formula The control method of a constant-voltage transistor converter to a constant, in which a rectangular voltage proportional to the reference voltage is applied to the control input of the power transistor, and the output voltage is removed from the filter capacitor after voltage is rectified from the output secondary winding which is included in the emitter circuit of the power (Transistor, characterized in that, with a reliability increase stage by eliminating current) the output overload of the power transistor, the amplitude of the voltage change by the magnitude of the reference voltage, is measured by the filtering capacitor with the frequency being in phase and proportional to the conversion. and. Won 0 t FIG. 2