SU1636933A1 - Three-phase winding of ac motor - Google Patents

Abstract

The invention relates to electrical engineering, in particular to the combined windings of alternating current machines, and can be used in single-machine frequency converters, in the rotor windings of synchronous and asynchronous cascade machines and dual-feed machines. The aim of the invention is to improve the utilization of copper and increase the efficiency. When powered by three-phase current, the winding creates two oppositely rotating magnetic fields with pole numbers 2p, 2 and, whose maximum values of induction are the same. 5 il.

Description

The invention relates to electrical machines, in particular to the combined windings of alternating current machines, and can be used in single-machine frequency converters, in the rotor windings of synchronous and asynchronous cascade machines and double- machines. foot food.

The purpose of the invention is to improve the use of copper and increase efficiency.

Figure 1 shows the scheme of the winding with 2P, 2, made in 36 slots; Fig. 2 shows the VAT of the winding for the moment of time in Fig. 3; the same, the scheme of decomposing the VAT into two harmonics; on - MDS winding for moments

that time is rad; Fig. 5 is the same, the MDS decomposition scheme into two harmonics.

The winding (Fig. 1) is three-phase, single-layer, the phase windings are connected into a star and consist of successively connected coils. All coil you-. Filled with the same number of turns. The winding is made in the magnetic core with the number of grooves with numbers from 1 to 36 and the number of coils with numbers from 1K to 18K.

Coils with numbers 1К, 2К, ЗК, 6К, 7К, 8К, 10К, 11 К, 12К, 15К, 16К, 17К are made in increments, coils with numbers 4К, 5К, 13К, 14К are made in increments, coils with numbers 9К, 18K are made in increments, coils with the numbers 1К, 2К, ЗК, -5К, -12К, -И 1К, -10К, 14К are included in phase А, coils with numbers 6К, 7К, 8К, 1ЗК, -17К are included in phase С , -16К, -15К, -4К, coils with numbers 9К, -18К are included in phase B. Sign mioe with

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nous at the coil number means counter switching. ) The winding coefficients of the winding in figure 1 for a 2p-pole field (2p g 2) phases A and C - COBI 0.230, phase B -, 996. For 2p-pole floor (2p,) winding factors of phases

TO

OB, 2.

A and C -, 827, phase B - 0.965.

Figure 2 shows the MDS winding shown in figure 1, for the moment of time, when the current in phase A is maximum positive, i.e. flows from the beginning of the phase to the end, and the currents in the B and C phases of half amplitude are negative. The ordinates of the MDS curve are proportional to the numbers of turns of the coils and the magnitudes of the currents. FIG. 3 shows a scheme for decomposing the resulting MDS into two harmonics: the first and the third. Figure 4 shows the MDS winding for

ten

16369334

The proposed combined winding is used instead of two windings: 2p, (- pole and 2p - pole (,), which improves the use of copper wire in the stator, simplifies manufacture and increases stator reliability: instead of four layers of copper, only one layer takes place in each slot .

When shorting the clips A, B, C, the considered winding can be used as the rotor winding of synchronous and asynchronous cascade machines and dual power machines. If the stator winding in such machines creates a 2p, -polar field, an emf is induced in the rotor winding, under the influence of which a current is generated across the winding, creating a rotating in opposite directions 2p4-pole and 2p-pole fields.

15

20

point in time

now

radian, current in

phase B is maximum negative, and currents in phases A and C of half amplitude are positive. Figure 5 shows a scheme for decomposing the resulting MDS into two harmonics: the first and the third. From the comparison of FIG. 5 and 3 view7 noe that during the time t is the first and third

the harmonic MDS shifted in opposite directions with respect to the initial distance position,

ft equal rad.

Consequently, when the three-phase voltage is connected to the terminals A, B, C, the winding creates magnetic fields with a number of poles of 2p (and 2pg, rotating in opposite directions.

The maximum values of the induction of the 2p-pole and 2p-pole magnetic; the fields generated by the proposed winding are the same, which is the optimal ratio for a 50/200 Hz frequency converter. Also, the number of turns of all winding coils are the same, which improves the utilization of the copper wire and the slot space.

The considered winding can be applied as a stator winding of an asynchronous frequency converter at 200 Hz.

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Claims (1)

Invention Formula Three-phase winding of electric machines of alternating current, single-layer, with numbers of pairs of poles p and p2, where 2p (2 and with opposite rotation of poles, is made in the magnetic core with the number of grooves from 1 to 36 and the number of coils from 1K to 18K included in phases consistently, in order to improve the use of copper and increase efficiency, the coils with numbers 1K, 2K, 3K, 6K, 7K, 8K, 10K, 11K, 12K, 15K, 16K, 17K are made in steps and laid their beginnings in the grooves with numbers 1, 2, 3, 10, 11, 12, 19, 20, 21, 28, 29, 30, respectively, coils with numbers 4K, 5K, 13 , 14K are made in increments and laid with their beginnings into slots with numbers 4, 8, 22, 26, respectively, coils with numbers 9К, 18К are made with a step and laid down with their beginnings into slots with numbers 18, 36, respectively, in phase A there are included coils with numbers 1K, 2K, 3K, -5K, -12K, -11 K, -10K, 14K, in phase C include coils with numbers 6K, 7K, 8K, 13K, -17K, -16K, -1K, -4K, Phase B includes coils with numbers 9K, -18K, where the minus sign at the number of the coil means that it turned on again. Ik gk -P. 2 j I. L what  Ug four  I g Mr-C Jg