SU50885A1 - The device for maintaining the secondary voltage constant applied primary - Google Patents

Description

The main author's certificate issued by the same person, no. 41067, describes a device for maintaining the secondary voltage of a transformer with a constant applied primary through the use of a highly saturated magnetic circuit.

For this, the capacitance included in the primary circuit of the transformer is of such a magnitude that the circuit is close to the resonance at normal primary voltage, with the capacitance resistance prevailing over self-induction.

With such a ratio of resistance values, an increase in the impedance values of the transformer should occur with increasing voltage at its terminals.

In the present invention, which is a modification of the device according to the main author's certificate, No. is proposed to stabilize the secondary voltage not only when the primary voltage changes.

voltage, but also when changing the frequency of the supply current, apply an additional transformer with capacitive resistance in the primary circuit and with an unsaturated magnetic circuit.

The secondary winding of the specified transformer, having a smaller number of turns than the secondary winding of the main transformer, is connected against the latter in order to create an additional electromotive force compensating for the oscillation of the primary voltage.

In FIG. 1 is a schematic diagram of the proposed modification of the device; FIG. 2, 3, 4, 5, 6 and 7-respective voltage diagrams.

As already noted above, in the proposed device (Fig. 1), the complete stability of the secondary voltage is achieved by using a resonant transformer H with a saturated magnetic core and an additional compensating resonant transformer R. The compensating transformer has a non-magnetic gap, and its iron works on the straight part (below knee) magnetization curve.

The frequency response of this transformer can be adjusted. The secondary windings of the transformers are connected in such a way that their e. d. Ejjj. and fjjp are directed towards one another.

The operation of the device proceeds as follows. The voltage received from the saturated transformer varies little with changes in the mains voltage (Fig. 2). The voltage of the resonant transformer is directly proportional to the voltage of the network (Fig. 3). Therefore, at a certain ratio of the voltages of the resonant and saturated transformers can be obtained with a counter-switching windings. and others compensation of voltage variations of a saturated transformer.

FIG. 4 shows that by subtracting the characteristic from the characteristic E, jj, j-, a characteristic can be obtained, parallel to the abscissa axis, i.e., a fully stabilized voltage can be obtained.

The frequency characteristics of Ejj.F (f) for the saturated and resonant transformer are given, respectively, in FIG. 5 and 6. By adjusting the frequency response of a resonant transformer, it is possible to obtain for some limits the frequency variation of the supply current to compensate for the effect of frequency changes on the secondary voltage of a saturated transformer.

FIG. Figure 7 graphically shows the summation of the frequency characteristics of both transformers and the receipt on the resulting characteristic of the section / j-f, where a stable voltage is reached.

The required frequency response is achieved in the resonant transformer by an appropriate calculation and can be adjusted within certain limits by the resistance of the primary winding of the resonant transformer. The operating point in the frequency response can be adjusted by adjusting the non-magnetic gap of the resonant transformer. Instead of an adjustable gap, you can also obtain adjustment of the operating point of the frequency response by changing the capacitance or the number of turns of the primary winding.

Thus, in this scheme, by appropriate calculation and adjustment, compensation for changes in the voltage and frequency of the network is combined for some limits of these changes.

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Subtraction e. d. E of FIG. 4 and 7, as indicated above, was made on the basis that these e. d. when switching on, it differs in phase by an angle close to 180 °. In fact, in a resonant transformer, a section of the working part of the frequency response lies at a frequency below the resonant one. In this mode, e. d. capacity more e. d. self-induction primary winding. Similarly, in a saturated transformer, the operating mode is characterized by the fact that e. d. capacity more e. d. primary winding. It follows from this that phase e. d. secondary windings differ little between themselves. Based on the latter and can be approximately determined e. d. /:,; ,, folding algebraically e. d. „„

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and EPR. Some complication in considering the electrical processes occurring in the circuit is introduced by the presence of higher harmonics contained in the curve E. d. saturated transformer. However, the influence of higher harmonics does not fundamentally change the above explanation of the operation of the circuit. A stable AC voltage obtained at the terminals can also be used for operation in a rectifier. In this case, a stable DC voltage will be obtained.

Upon receipt of several voltages from this power supply circuit, it is rational to introduce a third transformer, the primary winding of which is powered by E. voltage. Similarly, the third transformer is appropriate.

apply, if necessary, adjust the resulting voltage. The adjustment in this case is made on the side of the primary winding.

The subject matter of the invention.

Modification of the device according to the author's certificate No. 41067, characterized in that, in order to stabilize the secondary voltage, not only when the primary voltage changes, but also when the supply current frequency changes, an additional transformer with a capacitance in the primary circuit and an unsaturated magnetic circuit is used the secondary winding of which, having a smaller number of turns than the secondary winding of the main transformer, is connected towards the latter in order to create an additional, compensating second oscillation voltage, electromotive force.

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