RU2267212C2 - THREE-PHASE SPLIT (q=2,75) WINDING OF ELECTRIC MACHINES - Google Patents

Abstract

FIELD: electric engineering and electro-mechanical industry, can be implemented in three-phase asynchronous and synchronous electric machines.

SUBSTANCE: three-phase split (q=2,75) winding of electric machines is made with grouping 3 3 3 2 two-layer 2p=8c-polar in z=33c grooves of 12c coil groups with numbers 1Γ...12(c)Γ with concentric coils with their average step of grooves y_c = 4, integer number c = 1, 2, ..., numbers i', i = 1...3 coils in groups, starting from external one, 2w_c coils of each groove. Also, in accordance to invention, in groups 1Γ...4Γ of first group three-coil groups have coil steps y_πi = 6 - 2(i - 1) with coil numbers (1 - x)w_c in i = 3 of groups 1Γ, 31 and in i = 1 group 2Γ, (1+x)w_c in i=2 group 2Γ, and two-coil 4Γ-y'_πi = 5-2 (i'-1) with coil numbers (1+x)w_c each for w_c coils in remaining coils of groups, while said distribution of not even-coiled coils is repeated in each following group, where x=0,48.

EFFECT: decreased differential dissipation σ_d of m' = three-zone split (q=z/3p=2,75) winding.

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 loop two-layer symmetrical m = 3-phase windings, performed by 2p-pole in z grooves from m'p coil groups with equal-step or concentric coils with their average pitch over 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 the differential scattering σ _d m '= 3-zone fractional (q = z / 3p = 11/4 = 2.75, d = 4) windings with a grouping of coils in a series of 3 3 3 2 [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 = 1,375, d '= 8 with the grouping 2 1 2 1 1 2 1 1, 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 = 2.75) winding with a 3 3 3 2 grouping performed by a two-layer 2p = 8c-pole in z = 33c grooves of 12s coil groups with numbers 1Г ... 12 (with ) T with concentric coils with an average of the grooves at step _k = 4, c = an integer 1, 2, ..., non-i ', i = 1 ... 3, the coils in groups, since the outer, 2w _to windings each groove:

Group 1D ... 4D first grouping three-coil groups are coils steps _pi y = 6-2 (i-1) with the numbers of turns (1-x) w i = a _to 3 groups 1G, 3G and i = 1 group 2r , (1 + x) w _k in i = 2 of the 2G group, and the double-coil 4G-y ' _pi = 5-2 (i'-1) with the number of turns in (1 + x) w _k when w _{to the} turns in the other coils groups, and the specified distribution of unequal 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 = 33 with numbers 1 ... 33, 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 (figure 3). With, for example, c = 2, the winding has 2p = 8c = 16, z = 33c = 66, 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, when q = _11/4 = 2.75 (N = 11, d = 4), for _pi = 6-2 (i-1) = 6, 4, 2 for groups of three-coil, y ' _pi = 5-2 (i-1) = 5, 3 double-coil (y _k = 4) winding coefficient K _vol.o for equal-coil coils (x = 0) is determined by the coefficients K _y = sin (90 ° y _k / τ _p ) shortening coils (with pole division τ _p = z / 2p = 33/8 = 4.125, for _k = 4), the distribution of K _p = sin (60 °) / Nsin (60 ° / N) and is equal to K _rev.o = K _y K _p = 0.827306. When neravnovitkovyh coils By _ob.o added to the value dependent on the index x and neravnovitkovosti determined considering shear axes groups 1G, 7G phase angles of ± α _p = 360 ° / z = 120 ° / 11 relative to 4D, 10D, coinciding with the axis phase symmetry to 4D + 10D-x (0,945008 + 0,909632 + 0,998867-0,75575 ) = + x2,0977506 _yi when K = sin (90 ° from _pi / τ _n) = 0.945008 ( y ' _pi = 5), 0.909632 (y' _pi = 3), 0.998867 (y _pi = 4) and 0.75575 (y _pi = 6), for 1G + 7G-2x0.690079cosα _p = -x1 , 355217 at 0.690079 K _yi = (y = 2 _pi) x (2,0977506-1,355217) / N = + h0,067503, then K and _an average pitch _p.sr y = Σ (y w _{pi Ki} ) / N are equal to:

и

and

From the MDS polygons of FIGS. 2 and 3 (in the center, the unit vectors of currents of 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. 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 value x _opt = 0.48 is calculated, which corresponds to σ _{d% min} : for x _opt = 0.48-K _rev = 0.85971, R ² _d = 59.8064 / 11, R _o = 33 · 0.85971 / 4π and σ _{d% min} = 6.67, and at x = 0-σ _d% = 13.64, t. e. σ _d% at x _opt = 0.48 decreases by 13.64 / 6.67 = 2.04 times; taking into account the increase in K _{about the} efficiency of the winding is equal to K _eff = (0,85971 / 0,82731) (13,64 / 6,67) = _2,12 at _y.s. = 4.09.

Note that m '= 6-zone winding with 2p = 8, z = 33, 6p = 24 groups, q = z / 6p = 1,375, for _n = 5, the parameters K _ob = 0.90275, σ _d% = 8 , 38, i.e. the winding of figure 1 with x _opt = 0.48 exceeds it by 8.38 / 6.67 = 1.26 times.

Thus, the proposed m '= 3-zone winding is characterized by increased K _about , lowered σ _d% and more efficiently in K _eff = 2.12 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 = 2.75) winding of electric machines, made with a group of 3 3 3 2 two-layer 2p = 8c-pole in z = 33c grooves of 12s coil groups with numbers 1G ... 12 (s) G, with concentric coils with their average step in grooves at _k = 4, the total number c = 1, 2, ..., numbers i ', i = 1 ... 3 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, three-coil groups have coil steps at _ni = 6-2 (i-1) with the number of turns (1-x) w _k , in i = 3 groups 1G, 3G and in i = 1 2r group, (1 + x) w _k in i = 2 2r group and dvuhkatushechnaya 4f y _'ni = 5-2 (i'-1) with numbers itkov by (1 + x) w w _k for the remaining coils _to coils of groups, wherein said distribution neravnovitkovyh coils is repeated in each successive grouping, where x = 0.48.

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