SU1026258A1 - A.c. voltage-to-d.c. voltage converter - Google Patents

Description

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The invention relates to electrical engineering, in particular, to devices for converting alternating voltage into increased constant voltage, and can be used in power supply devices for electronic and radio equipment.

A rectifying device is known, which contains a full-wave bridge rectifier made on two valves and two capacitors connected in a voltage double circuit, two additional capacitors and a choke 1

The drawbacks of the device are the increased level of output voltage ripple and the large dimensions of the device, determined by the choke and additional capacitors.

A device for multiplying the voltage, comprising valves and capacitors, connected in a single-step rectifier circuit 2.

The disadvantage of the device is a high level of output voltage ripple.

The closest to the present invention is an alternating voltage-to-constant voltage converter containing two voltage multiplying circuits connected in parallel on the input and in series on the output 33.

The drawback of the device is the high level of output voltage ripple. The output voltage ripples are caused, in particular, by the fact that the charge and discharge rates of series-connected capacitors of the voltage multiplier circuit are different, the capacitors of one of the circuits are almost instantly charged from the alternating voltage source, and the capacitors of the other circuit in this the time is discharged by the load current almost linearly. As a result, the output voltage of the converter is sawtooth, i.e. high level of pulsation. A decrease in the ripple level due to an increase in the capacitance of the capacitors of rectifier circuits is usually unacceptable, since this leads to a sharp increase in the dimensions of the device and an increase in the switching current.

The purpose of the invention is to reduce the ripple level of the output voltage.

The goal is achieved by the fact that a current-stabilizing two-pole device, connected in series with one of the input terminals, was inserted into the AC-DC converter containing two voltage multiplication circuits connected in parallel across the input and output sequentially.

FIG. 1 is a circuit diagram of a converter; figure 2 variants of the circuits of current-stabilizing two-terminal; in fig. 3 output plots.

The converter contains two circuits 1 and 2 voltage multiplication, parallel to the input and

successively on the output, and a current-stabilized two-port network 3 connected in series with one of the input terminals. FIG. 1 shows 0 rectifying patterns with triple voltage. Depending on the output voltage requirement, circuits with any multiplication factor, including one, can be used. Circuits I and 2 contain valves k, output capacitors 5 and 6, and additional capacitors 7 and 8, respectively.

The current-stabilizing two-terminal 0 3 can be made in the form of a rectifying bridge 9 with a field-effect transistor 10 in the diagonal of direct current (Fig. 2a) or in the form of a rectifying bridge 11 with a stabilizer 5 12 of the current (Fig. 26). Other schemes may be used.

The Converter operates as follows.

-, A variable rectangular voltage is applied to the input of the device. The charge current induced by it through the current. the stabilizing two-pole 3 and the valves k alternately charge the capacitors 5 8 and 6, 7- At the same time 5 the capacitors 5 and 6 are continuously discharged by the output current of the device. Thus, the output capacitors 5 and 6 are alternately charged, and the amount P1n11 is constant. When charged then. Ke, twice the load current, the voltage on the discharging and charging capacitors change at the same speed, and the ripple output voltage is absent.

5 The plots in FIG. 3 is taken as. pulsations are formed in the transform, the body containing two multiplication schemes connected in parallel along the input and

consistently on the output (line q), as well as with the introduction of the two-terminal 3 (line b.

A field-effect transistor 10 or a current stabilizer 12 on a bipolar transistor ensures the constant current of the capacitors 5 and 6 when the voltage on them changes.

Using the present invention allows simple technical means to reduce pulsations.

the output voltage of the rectifier with doubling or multiplying the voltage. The current-stabilizing two-port input is simple and has small dimensions. In the simplest case, a resistor can be applied. Reducing the ripple of the output voltage reduces the capacitance of the capacitors of the voltage multiplying circuit, and hence the device gab.

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Claims (1)

AC VOLTAGE CONVERTER TO CONSTANT, containing two voltage multiplication circuits connected in parallel at the input and sequentially at the output, characterized in that, in order to reduce ripple of the output voltage, a current-stabilizing two-terminal device is inserted into it, connected in series with one of the input terminals. ns> 1 1026258 2