SU1387141A1 - Transistor converter control device - Google Patents

Description

(21) 4045922 / 24-07

(22) 01/29/86

(46) 04/07/88. Bul № 13

(71) Murmansk Higher Marine Engineering School and the Research Institute of the Watch Industry.

(72) H. I. Bezgachin, V. B. Nikitin and A. N. Korobko

(53) 621.314.27 (088.8) (56) USSR Copyright Certificate No. 778846, cl. H 02 M 3/10, 1978. USSR Copyright Certificate No. 1249663, cl. H 02 M 3/10, 1985.

(54) DEVICE FOR CONTROLLING A TRANSISTOR CONVERTER

(57) The invention relates to electrical engineering and can be used in direct current converters. The purpose of the invention is to increase the reliability of the device. By introducing into the converter control device the single-oscillators 10 and 11, through which the comparator 4 is connected to the trigger 3 and the key 9, the influence of the discharge process of the integrator capacitor 8 on the pulse duration is eliminated. 2 Il.

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Phys. 1

The invention relates to electrical engineering and can be used to control transistor pulse-width DC converters. The aim of the invention is to improve the reliability of the device.

FIG. 1 shows a functional diagram of the proposed device; in fig. 2 - time diagrams that show his work.

The device contains a master oscillator 1, connected to the source 2 of the control voltage and the input of the RS-flip-flop 3, the source 2 is connected to one input of the comparator 4, the integrator 5, consisting of the operational amplifier 6, the resistor 7, the capacitor 8 and the discharge key 9, two single vibrators 10 and 11, the input of the first one is connected to the output of comparator 4, and the output is connected to the trigger input 3 and the single vibrator input -11, the output of which is connected to the control input of the key 9, the input of the integrator 5 is connected to the output of the sensor 12 output voltage converter. The time constant of the integrator assembled on the operational amplifier 6 is determined by the parameters of the resistor 7 and the capacitor 8.

The transistor converter contains a voltage source 13, a power transistor 14, an amplifier 15 of the power of the control signal of the transistor 14, a diode 16, a choke 17, a filter capacitor 18, a load 19.

The device works as follows.

The generator 1 generates narrow pulses that synchronize the operation of source 2 and are fed to the input of trigger 3, putting it into a state with high potential at the output. The high potential from the output of the trigger 3 to the input of the amplifier 15 causes the positive control current of the transistor 14 to flow (Fig. 2g), which leads to the unlocking of the transistor 14 and the appearance of a positive voltage on its emitter. At the same time, a voltage, Ufl, is formed at the output of the sensor 12, proportional to the instantaneous value of the output voltage of the converter to the filter (Fig. 26). This voltage, at the input of the integrator 5, leads to a linear increase in voltage and at its output (Fig. 2c), which determines the duration of the open state of the transistor 14, necessary for accurate stabilization of the output voltage at the level specified by the control voltage and the source 2.

When the voltage UH reaches the voltage Uy, the comparator 4 will generate a pulse whose front triggers one-shot

Rator 10 (Fig. 2d, d). A short pulse is generated at the output of the single-vibrator 10, which is fed to the input of the trigger 3 and to the input of the one-vibration 11. The pulse of the single-vibration 10 sets the trigger 3 to its initial state, which leads to a change in the polarity of the control current of the transistor 14 (Fig. 2e, g ) and the resorption of charge carriers in the database. By the decay of the pulse of the one-shot 10, the one-shot AND is started (Fig. 2e, e). The duration of the output pulse of the one-shot 11 is chosen so that during this time the capacitor 8 has managed to discharge, because the pulse of the one-shot 11 closes key 9. The purpose of the one-shot 10 is to delay the start of the discharge of the capacitor 8 by a time sufficient for reliable operation comparator 4, since the pulse formation time at the output of the latter is determined by the time during which. For high-speed comparators, the switching time is usually short, so the pulse duration of the single-vibrator 10 may be short, which does not lead to any noticeable error in stabilizing the output voltage. The single-oscillator 11 allows you to select the minimum required duration of the discharge of the capacitor 8, sufficient for reliable operation of the device in all modes.

Thus, the use of the proposed device allows increasing the reliability of the device for controlling a transistor converter by eliminating the influence of the discharge process of the integrator capacitor on the pulse duration generated by the comparator.

Claims (1)

Invention Formula A device for controlling a transistor converter containing a master oscillator, the first output of which is connected to the S-input of the RS flip-flop, the output of which is the apparatus output, the second output of the master oscillator through a source of control voltage, the integrator, containing a bit switch, the integrator input is connected to the output of the sensor output voltage of the converter, the output of the integrator is connected to the second input of the comparator, characterized in that. in order to increase reliability, it is equipped with two one-shot, and the comparator output is connected through the first one-shot to the R input of the RS flip-flop, which is connected to the control input of the integrator's bit through the second one-shot. 0 five 0 Fi.2