RU2267852C2 - THREE-PHASED SPLIT (q=6,75) WINDING FOR ELECTRIC MACHINES - Google Patents

Abstract

FIELD: electric engineering and electro-mechanical industry, possible use for construction of three-phased asynchronous and synchronous electric machines.

SUBSTANCE: three-phased split (q=6,75) winding of electric machines is made with grouping 7 7 7 6, two-layer 2p=8c-polar in z=81c grooves of 12c coil groups with numbers 1Γ...12(c)Γ with concentric coils with their average step by grooves y_c=10, integer number c=1,2,..., numbers i',i=1...7 coils in groups, starting from external one, 2w_c coils of each groove. In accordance to invention, in groups 1Γ...4Γ of first grouping, seven-coil groups have coil steps y_gi=16-2(i-1) with coil number (1-x)w_c in i=7 of groups 1Γ, 3Γ and in i=1 of group 2Γ, (1+x)w_c in i=4 of group 2Γ, and six-coiled 4Γ-y'_gi=15-2(i'-1) with coil numbers (1+x)w_c in i'=3 and 4 for w_c coils in remaining coil groups, while aforementioned distribution of not even-coiled coils is repeated in next grouping, where x=0,48.

EFFECT: decreased differential dissipation σ_D of m'=3-zoned split (q=z/3p=6,75) winding.

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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).

Loop double-layer symmetrical 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 step in grooves at _n ≈ 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 at q = z / m'p = N / d create harmonic MDSs in the series ν = m'k / d ± 1 [ibid, p. 450], including the lowest ones (ν <1) for d≥ 4 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 reverse (-) rotation.

The invention aims to reduce differential scattering σ _d m '= 3-zone fractional (q = z / 3p = 27/4 = 6.75, d = 4) windings with a grouping of coils in a series of 7 7 7 6 [Livshits-Garik M Windings of AC Machines / Transl. from English M.-L .: SEI, 1959, p.224], equivalent to m '= 6-zone winding at q' = z / 6p = q / 2 = 3.375, d '= 8 with the grouping 4 3 4 3 3 4 3 3, but it is easier to manufacture due to half the number (3p) of coil groups.

The solution of this problem is achieved by the fact that for a three-phase fractional (q = 6.75) winding with a grouping 7 7 7 6 performed by a two-layer 2p = 8c-pole in z = 81c grooves from 12s coil groups with numbers 1Г ... 12 (with ) T with concentric coils with an average of the grooves at step _k = 10, c = an integer 1, 2, ..., non-i ', i = 1 ... 7, the coils in groups, since the outer, 2w _to windings groove:

in groups 1G ... 4G of the first grouping, seven-coil groups have coil steps y _pi = 16-2 (i-1) with the number of turns in (1-x) w _k in i = 7 groups of 1G, 3G and in i = 1 groups 2Г, (1 + х) w _к in i = 4 of the group 2Г, and six- _{coil 4Г} -y ' _пi = 15-2 (i'-1) with the number of turns (1 + х) w _к in i' = 3 and 4 when w _{to the} turns in the remaining coils of the groups, and the indicated distribution of non-uniform coils is repeated in each subsequent grouping, where x = 0.48.

Figure 1 shows a scan of the groove layers of the proposed winding at 2p = 8 (s = 1), z = 81 with numbers 1 ... 81, 12s = 12 coil groups with numbers 1G ... 12G (marked groups 1G, 4G, 7G, 10G of the first phase), by alternating phase zones in the sequence ABC of the upper and X, Y, Z lower layers, and in FIGS. 2 and 3 its MDS polygons are constructed (on a triangular grid) at x = 0 (FIG. 2) and x = 0.5 (Fig. 3). With, for example, c = 2, the winding has 2p = 8c = 16, z = 81c = 162, and the sweep of FIG. 1 is repeated twice. The winding at m '= 3 zones is connected in phases in the usual way with sequentially-consistent inclusion of phase groups: 1G, 4G, 7G, 10G with the beginning of the phase from the beginning of 1G in phase I; 3G, 6G, 9G, 12G with the beginning of 3G in phase II; 5G, 8G, 11G, 2G with the beginning of 5G in phase III; phases can mate into a star or triangle.

For the winding of Fig. 1 with q = _27/4 = 6.75 (N = 27, d = 4), y _pi = 16-2 (i-1) = 16, 14, 12, 10, 8, 6, 4 for groups of seven-coil, y ' _pi = 15-2 (i'-1) = 15, 13, 11, 9, 7, 5 six-coil (y _k = 10) winding coefficient K _vol. with equal-coil coils (x = 0) is determined by the coefficients К _у = sin (90 ° У _к / τ _п ) shortening (at τ _п = z / 2p = 10,125, y _к = 10), distribution K _p = sin (60 °) / Nsin (60 °) / N) and is equal to K _rev.o = K _y K _p = 0.827045. When neravnovitkovyh coils By _ob.o added to the value dependent on the index x and neravnovitkovosti determined considering shear axes 1G, 7G phase angles of ± α _p = 360 ° / z = 40 ° / 9 relative 4G 10G and phase symmetry axis: for 4G + 10G-x (0.99080 + 0.984808 + 0.999812-0.6126006) = + x2.362820 for K _yi = sin (90 ° y _pi / τ _p ) = 0.99080 (y ' _pi = 11), 0.984808 (y ' _pi = 9), 0.999812 (y _pi = 10) and 0.6126006 (y _pi = 16), for 1G + 7G-2xcosα _p 0.581492 = -x1.159487 when R _yi = 0,581492 (y _pi = 4), x (2,36282-1,159487) / 27 = + h0,044568, then K and _an average pitch _p.cp y = Σ (y w _{pi Ki)} / N are equal

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 _о is the radius of the circle for harmonic ν = 1 [Popov V.I. Determination and optimization of the parameters of three-phase windings for 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 = 0.48 is calculated, which corresponds to σ _{d% min} : for X _opt = 0.48-K _rev = 0 , 84844, R ² _d = 817.2576 / 27, R _o = 81 · 0.84844 / 4π, σ _{d% min} = 1.205, and at x = 0 - σ _d% = 2.435, i.e. σ _d% at X _opt = 0.48 decreases by 2.435 / 1.205 = 2.02 times; taking into account the increase in K _{about the} efficiency of the winding is equal to K _eff = (0.84844 / 0.827045) (2.435 / 1.205) = 2.07 at Y _{p cp} = 10.107.

Note that m '= 6-zone winding with 2p = 8, z = 81, 6p = 24 groups, q = z / 6p = 3.375, Y _n = 12 correspond to the parameters K _ob = 0.9149, σ _d% = 1 , 39, i.e. the winding of figure 1 with X _opt = 0.48 exceeds it by 1.39 / 1.205 = 1.15 times.

Thus, the proposed m '= 3-zone winding is characterized by an increased K _rev , a decreased σ _d% and more efficient K _eff = 2.07 times in comparison with an equal-turn winding; it is simpler m '= 6-zone winding in manufacturability due to half the number (3p) of coil groups.

Claims (1)

Three-phase fractional (q = 6.75) winding of electric machines, made with a grouping 7 7 7 6 two-layer 2p = 8c-pole in z = 81c grooves of 12s coil groups with numbers 1G ... 12 (s) G with concentric coils at their average step in the grooves y _k = 10, the total number c = 1, 2, ..., numbers i ', i = 1 ... 7 coils in groups, starting from the outer, 2w _{to the} turns of each groove, characterized in that in groups 1G ... 4G of the first grouping, seven-coil groups have coil steps y _pi = 16-2 (i-1) with the number of turns (1-x) w _k in i = 7 groups of 1G, 3G and in i = 1 groups 2Г, (1 + x) w _к in i = 4 of the 2Г group, and the six- _{coil 4Г} -y ' _пi = 15-2 (i'-1) with numbers turns (i + x) w _to i '= 3 and 4 for w _to turns in the remaining coils of the groups, and the indicated distribution of non-coils is repeated in each subsequent group, where x = 0.48.

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