SU1677815A1 - Controlled ac voltage converter - Google Patents

Abstract

The invention relates to electrical engineering. The purpose of the invention is to reduce the level of interference produced and to reduce the distortion of the shape of the output voltage. The converter contains a transformer with two parallel branches of the adjusting winding, which are taped through the same number of turns, by switching which the output voltage level is changed. The presence of a switching unit with mercury electrodes of a certain size, connected to the tapings of the transformer's adjusting winding through diodes, makes it possible to exclude controlled semiconductor elements from the circuit, thereby achieving the set goal. 2 hp f-ly, 2 ill.

Description

The invention relates to electrical engineering.

The purpose of the invention is to reduce distortion of the shape of the output voltage and reduce the level of generated noise.

FIG. 1 shows a functional diagram of the device; in fig. 2 - an example of the design.

The device of the switching unit (see Fig. 1) contains a transformer 1 with the main winding 2, an adjusting winding divided into two parallel branches 3. The desolders of the adjusting winding 4 are connected to the terminals 5 of the switches of the switching unit via diodes 6. The load 7 is connected to the terminals 8 of the keys switching unit through isolating diodes 9. The switch is controlled by the measuring body 10, comparing the element 11 through the amplifier 12. The switching unit (see Fig. 2) consists of a glass vessel 13 with hollow stems the lead electrodes, pin 5, and plate electrodes, pin 8, the moving mercury contact 14, the membrane 15 of the ferromagnetic core 16 and the coil 17. The vessel is filled with insulating liquid 18.

The device works as follows.

The voltage proportional to the voltage on the load 7 from the measuring element 10 is supplied to the comparison element 11, where it is compared with the predetermined voltage Uzad. With equal voltages at the output of the comparison element 11, there is no signal. The output of the amplifier 12 is maintained at a voltage sufficient to hold the ferromagnetic core 16 of the switch in an average position. In this case, the moving mercury contacts 14 provide for the inclusion of half of the volt-additional sections and a predetermined voltage is applied to the load. When changed to.

AND

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SL

A load voltage 7 at the output of the comparison element 11 appears as an error signal, which either increases or decreases the voltage at the output of the amplifier 12. The ferromagnetic core 16 moves the membrane 15, the mercury contacts 14 also move and increases or decreases the number of volt-add-ons sections,

In the positive half-cycle, the current flows through the main winding 2, part of the sections of the right branch 3 of the booster winding, one of the diodes 6, through pin 5 of the key of the switching unit, mercury contact 14, pin 8 of the switch’s key, isolating diode 9, load 7. V negative half-cycle includes booster sections of the left branch of the adjusting winding. When the mercury contacts close the outputs of two switches of the switching unit in the shorted section, the short circuit current does not flow, since one of the diodes 6 turns on in opposite directions. The spreading diodes 9 prevent the equalizing currents from flowing between the half-windings, since the maximum voltage between the two connected taps, equal to the section voltage, is chosen to be less than the direct voltage drop across the four diodes.

Shown in FIG. 2, the design form of the switching unit is not the only possible one. More simple can be a 0-shaped form. In this case, the pins 5 of one half of the switching unit must be connected to the diodes 6 in the reverse order.

Claims (3)

1. Adjustable alternating voltage converter containing a transformer or autotransformer, the control winding of which is divided into two parallel branches with tapes through the same number of turns, diodes by the number of taps and two switching blocks, each of which contains keys by the number of taps, characterized in that , in order to reduce the distortion of the output voltage form and reduce the level of generated noise, two decoupling diodes are inserted into it, and each tap is connected via a corresponding ciode and to one of the terminals of the corresponding key of the corresponding switching unit, the other terminals of the keys of each of the switching unit are connected and connected via a corresponding decoupling diode to one of the terminals for connecting the load, the other terminal for connecting of which is connected to the free terminal of the transformer, while the diodes are parallel the branches are connected to the corresponding tapings with anodes, and the diodes of the other branch are connected with cathodes, the decoupling diode of one branch is connected to the output for connecting the load with the anode, and nother branches - cathode. 2. The transducer according to claim 1, of which is the fact that the number of turns between adjacent tapes is chosen so that the amplitude value of the voltage between they did not exceed the voltage for unlocking the four diodes connected in series in the forward direction. 3. The Converter in PP. 1 and 2, which is based on the fact that two commuting the blocks are made in the form of a closed U-shaped or 0-shaped glass vessel, into the walls of which two groups of inlets in the form of rod electrodes are drilled according to the number of taps of each parallel branch, each of which is the output of one of the keys associated with a tap, and two leads connected inside the vessel with plate electrodes located on the inner wall against all the leads each group and the common conclusions of the keys of the corresponding switching units, the vessel being filled with insulating liquid, into which two mercury electrodes are inserted, in the lower part vessel, in expansion, is a diaphragm connected to a ferromagnetic core, and outside - a winding connected to the output of the amplifying element, which is connected at the input with a comparison element, the inputs of which are connected to the output of the measuring body and the source of the setting voltage, respectively, in addition the length of the mercury electrodes is greater than the distance between two adjacent rod electrodes and less than double the distance between two adjacent rod electrodes. t Uzi (Putt 18 FIG. Z