RU2270515C2 - ELECTRICAL-MACHINE THREE-PHASE DOUBLE-LAYER WINDING WITH 2p=10c POLES IN z=36c SLOTS - Google Patents

Abstract

FIELD: electrical and electromechanical engineering; three-phase induction and synchronous machines.

SUBSTANCE: proposed three-phase double-layer lap winding with 2p = 10c poles in z= 36c slots and coils grouped in row 3 2 3 2 2 repeated 3c times is made of 15c coil groups numbered 1G through 15(c)G with concentric coils at their mean slot pitch y_c = 4 and also at c = 1, 2, 3 ... Novelty is that in order to reduce differential dissipation σ_d of electrical-machine m' = 3-band fractional-pitch (q = 12/5) lap winding, three-coil groups 1G, 3G out of groups 1G through 5G of first grouping have pitches y_si = 6, 4, 2 of coils having turn numbers (1 - x)w_c, w_c (1 - x)w_c, and two-coil groups 2G, 4G, 5G have slot pitches y'_si = 5, 3 of coils with turn numbers w_c, (1 + x)w_c, respectively, mentioned distribution of coils with unequal turn number being repeated in each next grouping, where x = 0.38 is index of turn number inequality of phase groups.

EFFECT: reduced differential dissipation in electrical-machine fractional-pitch lap winding.

1 cl, 3 dwg

Description

The invention relates to three-phase windings of electrical AC machines, can be used on a stator of three-phase asynchronous and synchronous machines, a phase rotor of asynchronous motors (HELL).

Known double-layer loop symmetric m = 3-phase windings are known, performed by 2-pole in z grooves from m′p coil groups with equal-step or concentric coils with their average pitch along grooves y _p ≈z / 2p and the number of grooves per pole and phase q = z / m′p whole or fractional, where m ′ is the number of phase zones per pair of poles equal to m ′ = m = 3 — three-zone, or m ′ = 2m = 6 — six-zone windings [Voldek A.I. Electric cars. L .: Energy, 1978, S. 392-393]. Fractional windings with q = z / m′p = N / d and d≥4 create harmonic MDS in the series ν = m′k / d ± 1 [ibid, p. 450], including the lowest ones (ν <1 ) with a significant increase in differential scattering σ _d , where ± k is an integer giving the order of harmonic ν> 0 with its direct (+) or counter (-) rotation.

The invention aims to reduce differential scattering σ _d m ′ = 3-zone fractional symmetrical winding at 2p = 10 · with poles, z = 36 · with grooves (q = z / 3p = 12/5, d = 5) with a group of coils in a row 3 2 3 2 2 [Livshits-Garik M. Windings of AC machines / Trans. from English M. - L .: SEI, 1959, p.224], equivalent to m = 6-zone winding at q = z / 6p = q / 2 = 6/5 with the grouping 2 1 1 1 1, but it is simpler in manufacture due to half the number of coil groups, where c = 1, 2, 3, ... is an integer.

The solution of this problem is achieved by the fact that for a three-phase 2-layer winding at 2p = 10 · s, z = 36 · s with a group of 3 2 3 2 2, repeated 3 · s times, performed from 3p = 15 · s of coil groups with numbers 1 G ... 15 (s) G with concentric coils with an average groove pitch y _k = 4: in groups 1G ... 5G of the first group, three-coil groups 1G, 3G have coil steps at _pi = 6, 4, 2 s by the numbers of turns (1-x) w _k , w _k , (1-x) w _k , and the double-coil 2Г, 4Г, 5Г - у ' _пi = 5, 3 with the number of turns w _k , (1 + x) w _k , moreover, the specified distribution of unequal coils is repeated in each subsequent groups e, where c = 1, 2, 3, ... - an integer, and x = 0.38.

Figure 1 shows a scan of the groove layers of the proposed winding with c = 1, 2p = 10, z = 36 with numbers 1 ... 36 and 15 coil groups with numbers 1G ... 15G (marked groups 1G, 4G, 7G, 10G (13G of the first phase), by alternating phase zones in the sequence ABC of the upper, X, Y, Z lower layers, where the blackened grooves contain (2-x) w _k turns at 2w _k turns in all other grooves, and in FIG. .2 and 3 are constructed (along a triangular grid) its MDS polygons at x = 0 (Fig.2) and x = 0.5 (Fig.3). This m ′ = 3-zone winding is connected in the usual way with the series-consonant inclusion of groups: 1G, 4G, 7G, 10G, 13G with the beginning of the phase from the beginning of 1G in phase I; 6G, 9G, 12G, 15G, 3G with the beginning of 6G in phase II; 11G, 14G, 2G, 5G, 8G with a start of 11 G in phase III; phases can be conjugated by a star or a triangle. At c = 2, 3, ... the winding has 2p = 10s = 20, 30, ... poles at z = 36c = 72, 108 grooves.

For the winding of Fig. 1 with q = _12/5 (N = 12, d = 5) Y _pi = 6, 4, 2 for three-coil groups, y ′ _pi = 5.3 double-coil (y _k = 4), the winding coefficient K _vol. at equal-coil coils (x = 0) in terms of shortening coefficients K _y = sin (90 ° y _k / τ _p ) at τ _p = z / 2p = 3.6, distribution K _p = sin (60 °) / Nsin (60 ° / N) is equal to K _about.o = K _at K _p = 0,815464. For unequal coils, a _value dependent on the non- _uniformity exponent x of the phase groups is added to K _r.o. , for the axis of symmetry along the 7G axis and shifts of ± α _p = 360 ° / z = 10 ° of the 4G, 10G and ± 0.5α _p groups relative to it = 5 ° of groups 13Г, 1Г: x [0.965926 (1 + 2cosα _p ) -2 (0.50 + 0.766044) cos0.5α _p ] = x0.34598 at К _yi = sin (90 ° at _pi / τ _p ) = 0.50 (for _pi = 6), 0.766044 (y _pi = 2) and 0.965926 (y ′ _pi = 3), then K _about at K _about · N = 9.785569 :

From the MDS polygons of FIGS. 2 and 3 (in the center, the unit current vectors of the phase zones A-Z-B-X-C-Y are shown) is determined by the relations

differential scattering coefficient σ _d , characterizing the quality of the winding by the harmonic composition of its MDS, where R ² _d is the square of the average radius j = 1 ... N of the groove points, R _o is the radius of the circle for harmonic ν = 1 [Popov V.I. Determination and optimization of the parameters of three-phase windings along the MDS polygons // Electricity, 1997, No. 9, p. 53-55]:

then, according to (1) - (3), from the condition d (σ _d ) / d (x) = 0, the optimal x _opt = 0.38 is calculated, which corresponds to σ _{d% min} : for x _opt = 0.38-z _e = 3 (Nx) = 3 · 11.62 = 34.86 - the equivalent number of completely filled grooves, K _rev = 0.85345, R ² _d = 46.7516 / 12, R _o = z _e K _rev / pπ = 34.86 0.85345 / 5π and σ _{d% min} = 8.60, and at x = 0σ _d% = 21.68, i.e. σ _d% at x _opt = 0.38 decreases by 21.68 / 8.60 = 2.52 times due to the elimination of the lower ν = 1/5 harmonic MDS; given the increase in K _about its effectiveness is equal

K _eff = (0.85345 / 0.815464) (21.68 / 8.60) (z _e / z) = 2.555.

We note that the m ′ = 6-zone winding at 2p = 10, z = 36, q = z / 6p = 6/5, and for _n = 3, the parameters K _ob = 0.9236, σ _d% = 11.59, those. the winding of figure 1 with x _opt = 0.38 exceeds it by 11.59 / 8.60 = 1.35 times.

Thus, the proposed m ′ = 3-zone winding is characterized by an increased K _rev , a decreased σ _d% and more efficient K _eff = 2.55 times in comparison with an equal-turn winding; it is simpler than the m = 6-zone winding in manufacturability due to the half as many (3p) coil groups, it exceeds its differential scattering by 1.35 times.

Claims (1)

Three-phase two-layer electric machine winding with the number of poles 2p = 10 · s in z = 36 · c grooves with a grouping of coils in a row 3 2 3 2 2, repeated 3 · s times, performed from 2p · s = 15 · from the coil groups with numbers 1G ... 15 (s) G and with concentric coils with an average step along the grooves y _k = 4, characterized in that in the coil groups 1G ... 5G of the first group, the three-coil groups 1G, 3G have steps along the grooves y _pi = 6 , 4, 2 coils with the number of turns, (1-x) w _k , w _k , (1-x) w _k, respectively, and the two-coil groups 2G, 4G, 5G have steps along the grooves y ' _pi = 5, 3 coils with numbers of turns w _k (1 + x) w _to ootvetstvenno, said distribution neravnovitkovyh coils is repeated in each subsequent group, wherein a = 1, 2, 3, ... - an integer, x = 0.38 - figure neravnovitkovosti phase groups.

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