SU1365267A1 - Three-phase switched-pole winding - Google Patents

Abstract

The invention relates to electric machines and can be used in asynchronous short-circuited electric motors with stepped angular velocity control by switching the number of pole pairs of the stator winding. The aim of the invention is to expand the scope by obtaining the ratio of the numbers of pairs of poles P, / P 1/7. The winding consists of short-circuit 21 coil groups (CG), and the CG is connected in series according to the following parts: 1.4, 7 into part 411; -2.5 into part 412; 3.6 to part 413; 10.13 to part 421; 8.11, 14 to part 422; 9.12 to part 423; 16.19 in part 431; , 17.20 in part 432; 15,18,21 to part 433. Three-pole switches are connected in series-according to three winding parts in each phase so that parts 411, 412, 413 with P 1 and parts 411, 421, 431 with P 7 enter into phase A, parts 421, 422, 423 with P 1 and parts 412, 422, 432 with P 7 enter into phase B, parts 431, 432, 433 with P 1 and parts 413, 423, 433 with P 7 enter into phase C. With both numbers of pairs of poles, the phases are connected into a star. 3 ill., 1 tab. (L

Description

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The invention relates to electric machines and can be used in electrical engineering to create two-speed asynchronous short-circuited motors with step-by-step angular velocity control in the ratio of 7: 1 by switching the number of pairs of poles of the stator winding.

The purpose of the invention is to expand the field of application of the winding by obtaining the ratio of the numbers of pairs of poles PI: P 1: 7.

Fig. 1 shows a circuit diagram of an offered winding with S V and Z 21; in fig. vector diagrams of slotted EMF windings; on fig.Z - schema-scan winding at S 1, Z 21.

The winding contains nine parts numbered 411, 412, 413, 421, 422, 423, 431, 432, 433 and three-pole switches (contactors) P1 and P2, which are used to switch the number of pole pairs. FIG. in parentheses are the numbers of coils included in the corresponding parts of the winding.

The top position of the switch corresponds to turning on the winding for one pair of poles (P P 1), and the bottom one - for seven pairs of poles (P

 R 7 7).

The phases A, B and C- (Fig. 1) for different numbers of pairs of poles include coils, the numbers of which are listed in the table (from 1 to 21).

The rows of the table show the numbers of the coils included in phases A, B and C when the winding is turned on by one pair, the poles, and the columns indicate the numbers of the coils included in the phases A, B and C when the winding is turned on seven pairs of poles , in parentheses are the numbers of the winding parts, which include the corresponding coil groups.

In the transition from the scheme with P 1 to the scheme with P. 7 parts 411, 422 and 433 remain in the composition of the previous phases, parts 412, 423 and 431 switch to adjacent phases on the right (from phase A to phase B, from B to C and from C to A) and portions 413, 421 and 432 are switched to adjacent phases on the left (from phase A to phase C, from C-to-B-to-A). Those most are provided with the upper position of the switches maximum

0

the amplitude value of the spatial harmonic of the MDS with a period of 2 iTD / l, i.e. the winding creates a rotating field with one pair of poles (P, 1), and at the lower position of the spatial harmonic of the MDS - with a period of 2 1 (B / 7, i.e., the winding creates a rotating field with seven pairs of poles (P 7).

Figure 2 shows the vector diagrams of the slot EMFs of the proposed winding consisting of 21 coils (, Z 21), with the upper vector diagram referring to the circuit with one pair of poles, and the lower to the circuit with seven pairs of poles. In accordance with the generally accepted rules, the coils are assigned the numbers of grooves in which their upper coil sides lie.

0 Coils are numbered 1-21 (Fig. 2) to which the corresponding EMF vectors belong (one, two, and three strokes mark the EMF vectors of the coils included in phases A, B, and C so5, respectively).

The proposed winding with both numbers of pairs of poles is symmetrical, has continuous phase zones 2ii / 3 wide erad and also the same number of coils under different poles, i.e. the winding is intact and does not create low harmonics MDS.

In FIGS. 3, the letters H and K denote the beginnings and ends of nine corresponding winding parts.

Winding works as follows.

When switches P1 and P2 are set to the upper position, the circuits between the upper and middle contacts of the switches and the coil groups are distributed in phases A, B and C as indicated in the rows of the table. When connecting the winding to the three-phase

5, the sinusoidal currents flow through it and the winding creates in the air gap of an induction motor a magnetic field with one pair of poles, which rotates at an angular speed of 3000 rpm at a frequency of 50 Hz.

When switching the switches P1 and P2 to the lower position, the chains between the lower and middle contacts of the switches and the coil contacts close.

5 groups are distributed in phases A, B and C of the winding as indicated in the columns of the table. When turned on in a three-phase network, such a winding creates a magnetic field in the air gap with

five

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seven pairs of poles that rotate at an angular speed of 3000 / / 7 rpm in the same direction as in the first case. This also provides stepwise regulation of the angular velocity of the engine in the ratio of 7: 1.

Claims (2)

Invention Formula A three-phase pole-switching winding is two-layered with an integer number of coils per phase zone of electric radians wide, connected into a star for both numbers of pole pairs, consisting of identical evenly distributed coils connected: B nine parts with numbers 411, 412, 413, 421, 422, 423, 431, 432, 433 and two three-pole switches, each of which has three groups of terminals with three terminals in each group — upper, middle and lower; and C respectively, and their con s - with the first, second and third upper pins of the first switch, the beginning of parts numbered 412, 423, 431 are connected to the first, second and third middle pins of the first switch, and nx ends to the first, second and third upper pins of the second switch, start parts numbered 413. 421, 432 are connected to the first, second and third middle terminals of the second switch, and their ends are interconnected, the switches are equipped with jumpers connecting the first lower to the second upper, the second lower to the third upper and the third lower per top of each switch, different from the fact that, in order to extend the application area by obtaining the ratio the number of pairs of poles, 1/7, the winding is made of nine coil groups in S series-according to the included coils, and the coil 5 groups with numbers 1,4 and 7 are included in series-according to part with number 411, coil groups with numbers 2 and 5 are included in series-according to part with number 412, 0 coil groups with numbers 3 and 6 are included in series-according to part 413, coil groups with numbers 10 and 13 are included in series-according to part with number 5 421, coil groups with numbers 8, 11 and 14 are included according to part c number 422, coil groups with numbers 9 and 12 are included according to part 423, coil groups number 16 and 19 are included according to part 431, coil groups numbers 17 and 20 are included according to part 432, coil groups with numbers 15, 18 and 21 are included according to part with but measure 433, where S is a positive integer. 0 five 1, 4, 7 (411) 2, 5 (412) 10, 11 (421) 8, 11, 14 (422) 9, 12 (423) 16, 19 (431) 17, 20 (432) 15,18,21 (433) 3, 6 (413) 20 15 3.6.3.12 rS.JS.Z Z Zt, y, a, p ,:}, I 0 о о о о 0 fc Р qs: And g 111 I K f t .-. 7.W, 13.16.19. 2.S.S.t1}, r7.ff Sh yy 73 K rs sixteen P Js s Th // 6 6 o-o -v CSI fO Helli