RU2324275C2 - THREE-PHASE DOUBLE-LAYERED ELECTRIC MACHINE WINDING IN z=120·c SLOTS WITH 2p=22·c POLES (q=40/11) - Google Patents

Abstract

FIELD: electric machinery industry.

SUBSTANCE: three-phase double-layered electric machine winding in z=120 c slots with 2р=22·c poles with number of slots per pole and phase defined as q=z/3p=40/11 is composed of 3р c=33·c coil groups with numbers from 1G to 33G c and with coils grouping as 44344344343 sequence repeated 3 times. In 1G...11G groups of the first grouping concentric coils have slot pitches of y_si =8, 6, 4, 2 with numbers of turns (l-x)w_K, (l+x)w_K, w_K, (l-x)w_K for four-coil groups, and y'_si=7, 5, 3 with w_K, (l+x)w_K, w_K turns for three-coil groups. At that, the said distribution of coils with different number of turns repeated in every next grouping, where c=1, 2, 3, ..., 2w_K is the number of turns in those slots that are completely filled with winding, and х = 0.58.

EFFECT: lowering of differential scattering σ_d of m'=3-zone symmetrical fractional-slot lap winding of electric machinery.

4 dwg

Description

The invention relates to the 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 2-pole in z grooves from m'p coil groups with equal-step or concentric coils with an average pitch of y grooves _to ≈τ _p = z / 2p, the number of grooves per pole and phase q = z / m'p whole or fractional, where m '= 2m = 6 or m' = m = 3 is the number of phase zones per pair of poles [Voldek A.I. Electric cars. L .: Energy. 1978, p. 392-393]. Fractional windings at q = z / m'p = N / d and d≥2, not a multiple of m = 3, create, with a symmetric sinusoidal current, harmonic MDSs in the series ν = m'k / d ± 1 [ibid, p. 450 ], including lower ones (ν <1) with increasing differential scattering σ _d , where ± k is an integer giving the order of harmonic v> 0 with its forward (+) and counter (-) rotation.

The invention seeks to reduce the differential scattering m '= 3-zone two-layer winding in z = 120 from 3p · with coil groups grouped in a series of 4 4 3 4 4 3 4 4 3 4 3 repeated 3 · times [Livshits-Garik M. Windings of AC machines / Trans. from English L .: SEI, 1959, p.225].

The solution of this problem is achieved by the fact that for a three-phase two-layer electromachine winding in z = 120 ..33Г · s and a group of coils 4 4 3 4 4 3 4 4 3 4 3, repeated 3 · s times:

in groups 1G ... 11G of the first grouping, concentric coils have _groove steps for _pi = 8, 6, 4, 2 with the number of turns (1-x) w _k , (1 + x) w _k , w _k , (1- x) w _k for groups of four- _coil and y ' _pi = 7, 5, 3 with w _k , (1 + x) w _k , W _k turns for three-coil, and the indicated distribution of unequal coils is repeated in each subsequent group, where c = 1 , 2, 3, ..., 2w _k is the number of turns of the grooves completely filled with the winding, and the value x = 0.58.

Figure 1 shows a scan of the groove layers of the proposed winding at c = 1 and z = 120 for groups 1G ... 11G of the first group (numbered above), z '= z / 3 = 40 grooves with numbers 1 ... 40 (bottom ) and alternating phase zones in the sequence A-B-C and XYZ of the upper and lower layers, where the blackened grooves are incomplete with equivalent z _e = 3 (N-3x) grooves completely filled with winding, Fig. 2 shows a diagram of the shift of the axes of the groups phase A relative to the axis of symmetry 10G; figure 3, 4 are built on a triangular grid (with its side per unit length) polygons of the MDS winding of figure 1 with x = 0 (figure 3) and x = 0.5 (figure 4). Such an m '= 3-zone winding is connected in the usual way with sequentially-consistent inclusion in the phases of the groups 1G + (3k) G = 1G, 4G, 7G, ..., 12G + (3k) G = 12G, 15G, 18G ,. .., 23Г + (3к) Г = 23Г, 26Г, 29Г, ... in phases I, II, III, and the phases can be conjugated in Y or in Δ. For example, with c = 2, the winding is performed in z = 240 grooves and 2p = 44 poles from 66 coil groups.

For winding 1 ravnovitkovoy (x = 0), the winding factor K _{is about} by shortening K coefficients _y = sin (90 ° _{to the} y / τ _n) for _k = 5, y, τ _p = z / 2p = 60/11, the distribution of K _p = sin (60 °) / Nsin (60 ° / N) is equal to K _ob = K _y K _p = 0.8200, and when x ≠ 0 to K _{ob is} added the value of the non-uniformity of the coils of the groups, determined according to figure 2 when the grooves are shifted α _n = 360 ° / z = 3 °: -x (0.743145-0.987688 + 0.544639) (1 + 2cosα _n + 2cos2α _n + cos3α _n ) = - x2.08917 for 10Г + (1Г + 19Г ) + (+ 4D 16G) + (7D + 13D), 2 × 0,991445 (cos0,5α _n + cos1,5α _n) = + x3,95899 to 22g + 31G + 25G + _yi 28g when K = 0.743145 (at _pi = 8), 0.987688 (at _pi = 6), 0.544639 (y _pi = 2), 0.991445 (y ' _pi = 5), then at K _both N = 32.80048, ∑x = 1.8698

Of the polygons of the MDS of Figs. 3 and 4 (in the center, the unit vectors of the currents of the phase zones are shown) according to a triangular grid and relations [Popov V.I. Determination and optimization of the parameters of three-phase windings according to their polygons MDS // Electricity, 1997, No. 9, p.53-55]

the differential scattering coefficient σ _d% is determined, which characterizes the quality of the winding according to the harmonic composition of the MDS, where R ² _d is the square of the average radius j = 1 ... N = 40 groove points, R _o and K _rev are for harmonic ν = 1:

According to (1) - (3) from the condition d (σ _d ) / d (x) = 0, the optimal x _opt = 0.58 is calculated, corresponding to σ _{d% min} : K _rev = 0.88565, R ² _d = 359, 3544/40, R _o = 114.78 · 0.88565 / 11π and σ _{d% min} = 3.82 (for the equivalent number of grooves completely filled with winding z _e = 3 (N-3x) = 3 · 38.26 = 114 , 78), and at x = 0-σ _d% = 8.53, i.e. the value of σ _d% at x _opt = 0.58 decreases by 8.53 / 3.82 = 2.23 times due to the elimination of harmonic MDS ν = 1/11; taking into account the increase in K _, its efficiency is equal to K _eff = (0.88565 / 0.8200) (8.53 / 3.82) (z _e / z) = 2.31 in comparison with an equal-turn (x = 0) winding. Compared to the m '= 6-zone winding at 2p = 22, z = 120, q = z / 6p = 20/11 and the grouping 2 2 2 2 2 1 2 2 2 2 1, having _k = 5, K _rev = 0.9469, σ _d% = 5.45, the proposed m '= 3-zone winding is characterized by a lower σ _d% 5.45 / 3.82 = 1.43 times, it is easier to manufacture due to half the number (3p) coil groups.

The application of the proposed winding on the HF stator allows reducing additional losses in steel and asynchronous moments from harmonic fields, improving vibration-acoustic characteristics, increasing the efficiency and cosφ ₁ overload capacity of the machine, and in synchronous generators it improves the shape of the output voltage curve.

Claims (1)

Three-phase two-layer electromachine winding in z = 120 · c grooves at 2p = 22 · s poles with the number of grooves per pole and phase q = z / 3p = 40/11, made of 3p · s coil groups with numbers from 1G to 33G · s and the grouping of coils in a series of 4 4 3 4 4 3 4 4 3 4 3, repeated 3 · s times, characterized in that in groups 1G ... 11G of the first grouping, the concentric coils have _groove steps in _pi = 8, 6, 4 , 2 with the numbers of turns (1-x) w _k , (1 + x) w _k , w _k , (1-x) w _k for groups of four- _coil and y ' _пi = 7, 5, 3 with w _k , (1 + x) w _a, w _{to the} windings for three-coil, said coils repeats distribution neravnovitkovyh Xia in each successive grouping, where c = 1, 2, 3, ...; 2w _to - the number of turns of the grooves, completely filled with a winding, and the value of x = 0.58.

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