SU1337976A1 - Device for controlling stabilized single-phase d.c.-to-d.c.voltage converter - Google Patents

Abstract

The invention relates to electrical engineering, in particular to static converters. The purpose of the invention is to increase reliability. In comparator 14, the reference and triangular voltages are compared and the pulse from its output goes to the first input of the element OR 15, to the second input of which impulses come from the master oscillator. The pulses from the output of the element OR 15, arriving at the base of transistor 1, open it, and current pulses appear in the collector circuit, which carry out the transformation of the source energy. When the output voltage of the source decreases, the output voltage of the reference element 5 decreases, the control transistor 6 closes, the triangular voltage amplitude increases, the duration of the output pulse of the comparator 14 increases, which leads to an increase in the pulse width of the collector current and, consequently, an increase in the output voltage. 2 Il. i (L H O g Sdd CO 0) Cpuff off

Description

The invention relates to an electrical technician, namely to a TpananTopiibiM pulsed constant-voltage constant-voltage transducer B constant.

The purpose of the invention is to improve the reliability of the stabilized converter.

FIG. 1 is a schematic diagram of the proposed control device for a stabilized DC / DC converter; Fig. 2 shows temporary dilations, which explain the operation of the control device.

The control unit is a constant-voltage DC-DC converter made on the power (1m transistor 1, the emitter of which is connected to the common power bus, and the primary winding of the power transformer 2 is connected to the collector, and the secondary winding through the rectifier 3 is connected to the filter 4, containing the comparison element 5, the input terminals of which are connected to the output of the filter 4, and the output terminals are connected to the input of the control transistor 6, emitter-collector A direct transition through diode 7 connects 1EL to the winding 8 of a control transformer 9, the output winding 10 of which is connected to the anode of the primary diode 11, the input winding 12 of the control transformer 9 is connected through the limiting resistor 13 to the output of the master oscillator and the end connected to the end of the output winding and connected to the common ;; .nne power, 1D comparator.

The control unit is additionally equipped with an element OR 1 i, a capacitor 16, a discharge resistor 17, a disconnecting chemical transistor 18 and a base resistor 19, and the condensate 16 is connected to the cathode of the protective diode 11 by one plate and the other emitter of the switching transistor 18 a resistor 17 and a common power bus, the second output of the discharge resistor 17 is connected to the collector of the opening transistor 18 and the second input of the comparator 14, the base resistor 19 is connected to the beginning of the output winding 10 of the transformer 9 , and others - to the base

disconnecting transistor 18, the first input of the comparator 14 is connected to the source of the reference voltage, and the output to the first input of the OR 15 terminal, the second input of which is connected to the output of the master oscillator, and the output to the base of the power transistor 1. The control unit is stabilized DC / DC converter operates as follows.

Rectangular conversion frequency impulses from the master oscillator with a period T of a duty cycle 2 are input to the device Ejr.

In the established mode of operation in the presence of voltage E

the output of the converter is set to the nominal output voltage and (curve and in fig. 2). The mismatch signal of the comparison element 5 maintains such a state of the reversing transistor 6, at which the amplitude of the triangular voltage (curve U; in Fig. 2) is equal to the set value and) determined by the ratio of the values of the resistor 13 and the open operating in linear mode control transistor 6. An increase in the degree of opening of the transistor 6 leads to a decrease in the amplitude U, as the resistor 13 drops most of the voltage Ej, and a smaller part falls on the winding 10 of the transformer 9.

The voltage supplied from the winding 10 of the regulating transformer 9 produces a charge on the capacitor 16 during the first half of the period bV. In this case, an increasing part of the triangular voltage is generated. At the end of this time, the polarity of the pulse E changes, the diodes 7 and I 1 are closed, and the transistor 18 opens, connecting the discharge resistor 17 to the capacitor

 6. A falling part of the triangular voltage is formed. When the pulse is positively polar, the transistor 18 is locked because a blocking voltage is applied to its base-emitter junction, equal to the voltage drop across the diode 11. Thus, the magnitude of the discharge resistor 17 does not affect the processes of charge of the condensate 1 f

Received) {th triangular voltage is compared in comparator 14 with reference Uarj (curve IJ in Fig. 2). When the instantaneous value of the triangular voltage exceeds the reference, a zero voltage level is generated at the output of the comparator, if the instantaneous value of the triangular voltage is less than the reference voltage, then a single voltage level is formed at the output of the comparator (curve Uj in Fig. 2). The pulse from the input of the comparator 1A arrives at the first input of the element OR 15, the second input of which receives the pulses Ejr. As a result of the addition of the incoming pulses, the pulses represented on the curve 15 form (shown in Fig. 2), the pulses At the base of transistor 1, it is opened, current pulses (curve U in Fig. 2) appear in the collector circuit, and the pulsed conversion of the energy of the constant voltage source E to a constant voltage at the load UH.

When changing the primary power supply of the EP, the load current or the voltage on the load UK, the converter control circuit fulfills all disturbances by changing the duration t, the pulse of the collector current i (curve Uj - in Fig. 2).

Let for some reason at time t, (curve U in Fig. 2, the output voltage decreases and to the value of Ip. This leads to a decrease in the output voltage of the comparison element 5, as a result of which the regulating transistor 6 will be closed, and the amplitude of the triangular the voltage will increase to U, o and the duration of the output pulse of the comparator 14 (curve U, j in FIG. 2) will increase. An increase in the duration of the pulse from the output of the comparator leads to an increase in the duration of the pulse of the kolletornoy current (curve 11 in FIG. 2), and consequently, an increase in the output voltage 1, to a given value.

Claims (1)

Thus, the formation of a triangular voltage across a capacitor increases the noise immunity and reliability of the operation of a stabilized DC / DC converter circuit. Invention Formula The control unit of a stabilized single-circuit DC-DC converter is performed on a power transistor, the collector circuit of which includes the primary winding of the power transformer, the secondary winding of which includes rectifiers and a filter containing a reference element whose output is connected to the input of the regulating transistor, the emitter-collector junction which through the diode is connected to the regulating winding of the regulating transformer, the output winding of which is Connected to the anode of the protective diode, the input start is connected through a limiting resistor to the output of the master oscillator, the ends of the output and input windings are connected to a common power bus, a comparator, the first input of which is connected to a source of reference voltage, characterized in that it is equipped with an OR element, a capacitor, a discharge T) ezis-TopoMj tripping transistor and a base resistor, with one capacitor plate connected to the cathode of the protective diode and the emitter of the tripping transistor, and the other - with the first output of the discharge resistor and the common power bus, the second output of the discharge resistor is connected to the collector of the opening transistor and the second input of the comparator, the base resistor is connected to the beginning of the output winding of the regulating transformer, the second to the base of the breaking transistor, and the output - To the first input of the OR element, the second input of which is connected to the output of the master oscillator, and the output is intended to be connected to the base of a power transistor. t Editor M. Dylyn Compiled by S.Stankevich Tehred L.Oliynyk Order 4139/51 Circulation 659 Subscription VRSHIPI USSR State Committee for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5 Production and printing company, Uzhgorod, st. Project, 4 fir.2 Proofreader M. Demchik