SU1598062A1 - Double-count rotary transformer - Google Patents

Abstract

The invention relates to electric machines of automatic systems and computer technology and can be used to create two-digit rotating transformers (DVT) having coarse and precise readings on a single magnetic circuit. The purpose of the invention is to improve the accuracy by reducing the mutual induction between the coarse counting excitation winding and the accurate counting output winding. The DVT contains a rotor and a stator, in the slots of one of which coaxial excitation windings of coarse and precise readings are laid, and in the grooves of the other, coaxial and precision readout windings are inserted. The coil excitation winding is made sinusoidally distributed with a shunt resistance connected in parallel, the value of which Z is defined by the expression Z = Z _o / 10, where Z _go is the coil resistance of the coarse excitation winding. 2 Il.

Description

The invention relates to electrical engineering, to the class of electrical machines of automatic systems and computer technology, in particular, to double-digit rotating transformers (DVT).

The purpose of the invention is to increase the accuracy by reducing the mutual induction between the coarse excitation winding and the precision coil output windings.

FIG. 1 illustrates the principle of construction of a DVT design; in fig. 2 - a basic circuit diagram of DVT.

DVT consists of coaxially positioned stationary stator housing 1 (Fig. 1) carrying the magnetic core 2, and a rotary housing of the rotor 3 carrying the magnetic core 4. On the magnetic conductors 2 and 4 of the stator and the rotor windings 5 are placed.

In principle, the field windings can be located both on the rotor and on the stator. In the proposed construction, the field winding is placed on the rotor, and the output windings on the stator.

On the rotor there are placed in series a multi-pole excitation winding 6 of an exact counting and a bipolar excitation winding 7 of a rough counting. The excitation winding of the exact reading can be any, both sinusoidally distributed and tooth-pole type. The coil excitation winding is made sinusoidally distributed, and in parallel it is connected to resistance 8, which in the general case can be any (active, reactive or mixed) in character, and its value (Z) is determined by the ratio Z Zro / k, where Zro is full coil rough winding resistance; / (- coefficient determined from the condition of reducing the mutual induction between the coarse excitation winding and the output windings of the exact counting.

The stator contains a pair of quadrature bipolar windings 9 and 10 of a rough reference and a pair of quadrature multipolar windings 11 and 12 of an exact reference with the number of pairs of poles p.

cl

with

00

about

05 N3

The output windings of the DVT are typically sinusoidally distributed. However, the multipole windings can be of the two-prong-pole type, i.e. lumped.

On the rotor can be placed a second pair of series-connected bipolar and multi-pole windings, the axes of which are shifted relative to the main by 90 Electr, deg.

Mala magnitude N.S. coarse excitation windings compared to n. the excitation winding of an accurate reading gives a reduction in the effect of a rough reading on an accurate reading. At the same time, with a small number of turns of the coarse excitation winding, a sinusoidal distribution of the turns of this winding in the slots of the magnetic core is not ensured, and therefore the spectrum and amplitude of harmonics n are greatly increased. c. due to the non-sinusoidal distribution of the turns associated with rounding the estimated number of turns. As a result, a parasitic flux linkage of the coarse counting excitation winding with an accurate counting output winding appears and the accuracy of the BEL is reduced.

In the proposed DVT, if the value of WV ' is increased 10 times, then the resistance Z is connected in parallel with this winding, the value of which is equal to I 7to / 10.

The transformer works as follows.

When voltage is applied, an alternating current is applied to the DVT excitation circuit (sequential connection of coarse and precise windings) depending on the angular position of the rotor (a) on the sine 11 and cosine 12 output windings of the exact count, voltage is proportional to sin pa and cos respectively pa, and the sine 9 and the cosine 10 coarse output windings induce voltages proportional to sina and cosa respectively.

0

The use of sinusoidally distributed windings instead of concentrated low-turn sections makes it possible to obtain in the decomposition of them N. only harmonics having a high order, defined by the ratio a Z ± (where Z is the number of teeth of the magnetic circuit carrying the excitation windings; a 1,2,3, ...), which greatly alleviates the problem of suppressing the interacting harmonics between the output windings of the exact reading and a rough reference excitation winding, since with a correct choice of the number of teeth of the magnetic circuit carrying the output windings, the possible coinciding harmonics have a very high order, and their action is negligible.

In this DVT, the number of turns of the coarse counting excitation winding is increased by a factor of Y, and the current passing through this winding is reduced by a factor of 10. Therefore, an increase in the number of turns in the coil excitation winding does not change the ratio of the magnetizing forces of the excitation windings of the accurate and coarse readings, each of which is proportional to the product IW.

25

Claims (1)

Invention Formula A two-count rotary transformer containing rotor and stator magnetic cores, in the slots of one of which coarse and accurate counting excitation windings are located, and the output windings in the slots of the other, characterized in that, in order to improve accuracy by reducing the mutual induction between the excitation winding of a coarse count and output windings accurate reading, coarse reference winding is made sinusoidally distributed, the rotating transformer is equipped with an electrical resistance element, the value of which corresponds to the condition for reducing the mutual induction between the coarse field excitation winding and the exact coil output windings. Stn "i roSot St / 7 / oi