SU1767646A1 - Stabilizing direct current power source - Google Patents

Description

one

(21) 4164536/07

(22) 12.22.86

(46) 10/07/92. Bul # 37

(72) V.D.Slezov, L.P.Kirasov and N.I. Naumov

(56) USSR Copyright Certificate No. 639338, cl. G 05 F 1/569, 1974.

Sources of secondary power supply. Reference book under the editorship of Yu I Konev, M., Radio and Communication, 1983, pp.169-172, fig.4.8. (54) STABILIZING DC POWER SUPPLY

(57) The invention relates to electrical engineering, in particular, to sources of secondary power supply for electronic equipment. The purpose of the invention is to improve the quality of stabilization of the output voltage by reducing the duration of the switching surge (when turned on). The power channel is made up of a series-connected adjustable single-ended voltage converter 1, a rectifier 2 and a filter 3. The feedback channel is formed by the error signal amplifier 5, comparing the voltage from the de-4

a voltage limiter 9 and a pulse width modulator 10, which receives a DC voltage from the output of the limiter 9 and a sawtooth voltage from a special generator. The adjustable single-ended voltage converter 1 is controlled by the output signals of the pulse-width modulator 10 through a matching amplifier 11. With an additional capacitor 12, a capacitive pulse-voltage divider consisting of a capacitor 12 and a correcting RC circuit 8 is formed. the input voltage is supplied an avalanche-like charge and a slower discharge of the capacitor 12 through the input resistance of the output stage of the error signal amplifier 5 and the correcting RC circuit 8. At the outputs of amplifier 5 and limiter 9, a pulse signal is formed with a monotonously decreasing falling edge. As a result, when the source is turned on, only a very short burst occurs.

with

XI o

Xi

oh oh

The invention relates to electrical engineering and is intended for use in the implementation of secondary power supply of electronic equipment.

The aim of the invention is to improve the quality of stabilization of the output voltage by reducing the duration of switching emissions.

Figure 1 shows the functional diagram of the described stabilizing source of DC power; on figa-in shows the timing diagram of the signals illustrating his work,

The device contains an adjustable one-voltage voltage converter 1, a rectifier 2, a filter 3, a voltage divider 4, an error signal amplifier 5 with feedback resistor 6 and a bias resistor 7, an RC correction circuit 8, a voltage limiter 9, bus - rotary pulse modulator 10, matching amplifier 11, additional capacitor 12. The diagram also shows the input pins 13, 14 for connecting the primary constant voltage, the output pins 15, 16 for connecting the load, pins 17, 18 related to outputs not shown n and, respectively, a reference voltage block and a sawtooth voltage generator. Adjustable single-ended voltage converter 1, rectifier 2 and filter 3 are connected in series between input terminals 13, 14 and output terminals 15, 16. The input of voltage divider 4 is connected to the output of filter 3. One of the inputs of error amplifier 5 is connected to the output of divider 4 voltages, another input to the output of the reference voltage block (with pin 17), and an output to the input of the voltage limiter 9, RC Correction circuit 8 is connected between the input potential output of the output stage of the error amplifier 5 and ne vym output terminal 15 source. One of the inputs of the pulse-width modulator 10 is connected to the output of the voltage limiter 9, the other input to the output of the saw-tooth voltage generator (with pin 18), and the output through the matching amplifier 11 to the control input of the adjustable one-stroke converter 1 wives An additional capacitor 12 is connected between the potential input of the output stage of the error amplifier 5 and the second output terminal 16 of the source,

The device works as follows.

When the source is connected at the time ti to the input voltage network Ux in the absence of an additional capacitor 12, the output voltage 1) The output contains a continuous voltage surge due to transients at the source and the inertia of the feedback circuit. If there is an additional capacitor 12, a capacitive impulse voltage capacitor consisting of a series-connected capacitor 12 and an RC correction circuit 8 is formed. In this case, at the time t of the input voltage UBX output

5, a voltage surge occurs in the form of a short positive pulse (peak), also due to transients (Fig. 2c). When this happens, an avalanche-like charge and a slower

0 is the discharge of the capacitor 12 through the input signal of the output stage of the error amplifier 5 and the RC correction circuit 8. As a result, a pulse signal is generated at the output of the amplifier 5

5 monotonously decreasing falling edge, which through voltage limiter 9 is fed to the direct input of a pulse-width modulator 10. The inverse input of the latter is supplied by a sawtooth voltage Uis (Fig.2, a), which starts, decreases in time, the voltage Ug from the output of the limiter 9 is compared in the pulse-width modulator 10 with the sawtooth voltage Die, and as a result, at the output of the given block from time t2, control signals are generated in the form of pulses Uy (Fig.2.6) variable (incremental) fill factor, These signals ly arrive at the input of the concordant

0 amplifier 11, and from its output to the control input of an adjustable single-ended voltage converter 1. Power switch of converter 1 is switched and voltage is transformed

5, the secondary winding of the output transformer, the straightening and filtering of the voltage is carried out in the rectifier 2 and the filter 3. The appearance at the output of the constant voltage source Uvyh leads to

0 action inertial feedback. The error signal amplifier 5 compares the voltage supplied to its direct input from the output of the divider 3 with the reference constant voltage on the inverse

5 entrance. The mode of operation of amplifier 5 is determined by resistors 6, 7. The error signal amplified by amplifier 6 is fed to the input of voltage limiter 9, which acts as a limiter for the duration of control signals. Ug voltage from output

limiter 9 is fed to the forward input of a pulse width modulator 10, where it is compared with a saw voltage Uis at its inverse input. Next, the processes are repeated, and the output voltage is stabilized at the moment of time 1h (Fig. 2c).

Introducing an additional capacitor 12 into the device allows, therefore, to improve the dynamic response of the stabilizing power source — to increase the speed of the feedback circuit. This predetermines the improvement in the quality of the output voltage stabilization.

Claims (1)

Invention Formula A stabilizing DC power source containing an adjustable single-ended voltage converter, a rectifier and a filter connected in series between the input terminals intended for connecting the primary constant-voltage source and output terminals intended for connecting the load 0 five 0 5 voltage divider, the input of which is connected to the output of the filter, the error signal amplifier, one of the inputs of which is connected to the output of the voltage divider, another input - to the output of the reference voltage unit, and the output - to the input of the voltage limiter, a corrective RC circuit, connected between the input potential output of the output stage of the error signal amplifier and the first output output of the source, a pulse-width modulator, one of the inputs of which is connected to the output of the voltage limiter, the other input with the output of the The sawtooth voltage regulator, and the output through the matching amplifier - with the control input of an adjustable single-ended converter, a voltage that is different from the fact that, in order to improve the quality of the output voltage stabilization by reducing the duration of the switching surge, it introduced an additional capacitor connected between the input potential output of the output stage of the error amplifier and the second output output of the source. s