SU1661924A1 - Rotary transformer - Google Patents

Abstract

The invention relates to electrical engineering and can be used to create high-frequency informational electrical machines. The purpose of the invention is to increase accuracy. A rotating transformer (VT) consists of a rotor and a stator with windings having the number of pole pairs P. On one of the rotor or stator magnetic cores there is a ring winding with a distribution of conductor numbers by grooves rounding the calculated values to integers according to the expression N _I = N _M COSP2 _I , where N _I - the number of conductors in the I-th slot

I - slot number

N _M - the maximum number of conductors in the winding groove

P - the number of pairs of poles

α - the angular position of the I - that groove. In this winding, the following relations are satisfied: ΣN _I SINK (2ϕ / Z ₁ ) I = 0, ΣN _I COSK (2ϕ / Z ₁ ) I = 0, where K = NZ ₂ ± P, N = 1, 2, 3, .. ., Z ₁ and Z ₂ - the number of working grooves of the magnetic circuit carrying the ring winding, and another magnetic circuit. 1 dw., 2 tab.

Description

The invention relates to electrical engineering and can be used to create high-precision electrical information machines.

The aim of the invention is to improve the accuracy.

The drawing is a schematic diagram of the mutual arrangement of the elements of the proposed rotating transformer (VT).

W contains a magnetic stator 1 with the number of slots zi and the magnetic rotor 2 with the number of slots Z2. On the magnetic cores are windings 3 and 4, with p pairs of poles. Each magnetic core may have two identical quadrature windings or one winding. One of the windings (for example, the winding 3 of the stator) is made annular with distribution

groove conductors according to the expression

NJ Nm cos r o ,,

(D

where NI is the number of conductors in the 1st slot;

I - slot number;

Nm is the maximum number of conductors of the windings in the groove;

p is the number of pairs of poles;

a - the angular location of the axis of the 1st slot.

The calculated numbers of NI conductors are rounded to integer values to enable real winding to be performed.

Unlike the prototype, in the proposed device, when rounding the calculated numbers of conductors to integer values, the relations

ON Os

YU

Yu

four

 one

Nisln K (27r / zi) l 0,

i 1

Ni cos K (2/21) I O

The winding 4, located on another magnetic core, can be annular or drum-shaped and have a distribution both uniform and sinusoidal. Since these windings (both uniformly and 4 and sinusoidal distributed) contain spatial harmonics in the expansion of their magnetizing forces, having the order of nz2 + p (where n 1,2,3 ...). In order to increase accuracy, it is desirable that the strongest of them (the lowest ones) should not have another magnetic circuit in the windings. Therefore, the choice of K values in expressions (2) is made from the number of harmonics determined by the expression

K nz2 ± p.

Usually these are 22 Ј p harmonics, if they are not suppressed by any other technical solution.

The fulfillment of expressions (2) ensures the absence of harmonics of order K in the magnetizing force of this ring winding, which eliminates the occurrence of mutual induction of the rotor and stator windings and leads to an increase in the accuracy of reproduction of the sinus dependence of the rotating transformer.

The correctness of the established relations (2) is confirmed by the fact that when they are executed, regardless of the law of padding, the conductors are divided into the grooves of the magnetic circuit in the expansion in the Fourier series of the law of the distribution of conductors in the magnetic core grooves of a harmonic of order K.

According to the example of the formation of an annular winding VT.

Let the magnetic circuit carrying the ring winding have the number of slots zi 21, and the other magnetic core has the number of slots Z2 32. The number of pole pairs will take p 5, the maximum number of conductors in the groove will take Nm - 100.

The origin of the angles щ in the calculation of the distribution of the windings is oriented so that one of the slots, taken for the first, is at an angle of 45 el. hail, from the beginning of the angle

"

360 °

(1-1).

(3)

The calculation of the distribution of the conductors of the winding in the grooves of the magnetic circuit for given parameters is given in Table 1 (columns

1-5). Column 5 shows the values of the numbers of conductors in the grooves, obtained in the same way as in the known rotating transformers, by rounding the calculated numbers

5 conductors (column 4) to the nearest integers with the condition that the numbers of conductors with positive and negative signs are equal. As a result of forced rounding of calculated values

The 10 numbers of conductors in the slots up to the integers violated the sinusoidal distribution and the additional spectrum of harmonics was observed. However, from this spectrum, the most

15 lower (strongest) harmonics whose numbers coincide with the spectrum nz2 + p (where n 1,2,3 ...) found in the windings of another magnetic circuit.

From this spectrum, the strongest harmonic, i.e. in our case the harmonic is K 32-5 27.

To determine the presence of the K 27 harmonic, we calculate the left sides of equality (2) for the calculated (column 5 of table 1) distribution of conductors along the grooves of the magnetic circuit. The results of the calculation of the left-hand sides of equalities (2) are given in table 2. Adding the values of the numbers in columns 6 and 7 of Table 2 will result in the values of the left parts of the equations

30 (2):

Z1

2 Ni sin K (2/21) I

I 1

OSZ1P jr

M At Ni sin 27 (4) I 0.974928;

one

Z1

Y, N | COS K (2 I / 21) I

40 1 1 21

2l

 Ј Nicos27 () i 1,222522. one

Therefore, expressions (2) are not fulfilled and a harmonic of the order of K 27 will introduce an additional error into the VT operation.

To eliminate this harmonic, Q should be introduced to correct (re-round) the law of distribution of conductors in the grooves of the magnetic circuit.

The introduced adjustment instead of the values N 94 and N20 -60, respectively g of the values N 95 and N20 59, leads to the satisfaction of equality (2).

The device works as follows.

When applying AC voltage to one of the windings, for example a winding

4, depending on the angular position of the rotor on another winding, for example winding 3, which is the output winding, a voltage proportional to sin p a will be induced. If there is an output (quadrature) winding, a voltage proportional to cos pa will be induced on it.

Claims (1)

BT makes it possible to increase the accuracy of reproduction of the sinus dependence of the output voltage on the rotor rotation angle by eliminating the mutual induction between the primary and secondary windings along one of the highest spatial harmonics from the spectrum nz2 + p (where n 1,2,3 ...). The invention includes a rotating transformer containing rotor and stator magnetic cores with windings, one of which is made with an annular winding having a distribution of conductor numbers by grooves rounding the calculated values to integer numbers by expression NI Nm cos pai, where Ni is the number of winding conductors in the I-M-slot; I - slot number; Nm - the maximum number of conductors in the winding groove; p is the number of pairs of poles; a is the angular position of the axis of the 1st slot, characterized in that, in order to increase the accuracy, the numbers of conductors in the slots of the magnetic circuit of the ring winding satisfy the ratios Z1 , 2l Nisin K (2rt / zi) l 0; Ni cos K (2 lg / zi) I 0,  one where K nz2 + p; n 1,2,3 ...; 21, r2 of the number of slots of the magnetic circuit carrying the ring winding, and another magnetic circuit, respectively. Table 1 0.7071 -0.6523 -O, 8046 0.5320 0.8841 -0,3999 -0,9439 0.2588 0.9826 -0.1120 -0,9993 -0.0374 0.9937 0.1859 0.9659 -0.3303 0.9166 0.4673 -0,8467 -0.5938 0.7570 71 -65 -81 53 88 -40 -94 26 98 -eleven -100 -four 99 nineteen -97 -33 92 47 -84 -60 76 71 -65 -81 53 88 -40 -95 26 98 -eleven -100 -four 99 nineteen -97 -33 92 47 -84 -59 76