RU2293426C2 - ASYMMETRIC FRACTIONAL-SLOT WINDING WITH 2p = 6c POLES PLACED IN z = 57c SLOTS - Google Patents

Abstract

FIELD: electrical and electromechanical engineering; three-phase induction and synchronous machines including slip-ring induction motors.

SUBSTANCE: novelty is that in proposed asymmetric three-phase fractional-slot lap winding with m' = m = 3-bands at 2p = 6c poles and z = 57c, with slots per pole per phase q = z/3p = 19/3 assembled of 3 pc coil groups 1G through 9G, with coil grouping 7 6 6 6 6 7 6 7 6 repeated c times, slot pitch of its concentric coils y_si = 15 - 2(i - 1) and turn number is (1 - x)w_c for coils with i' = 1.7 and turn number is (1 + x)w_c for coil with i = 4 in seven-coil groups 1G, 6G, 8G; slot pitches y'_si = 10 - 2(i' - 1) and turn number (1 + x)w_c for coil with i' = 3 in all six-coil groups; turn number equals (1 - x)w_c for coils with i' = 6 in coil groups 3G, 4G, 7G, 9G, and for coil groups 2G, 5G at slot pitch y_s = 9, turn number equals (1 - x)w_c; for coil with i' = 6 in coil group 2G and for coil with i' = 1 in coil group 5G; turn number in remaining coils of coil groups equals w_c, where c = 1, 2, 3....; i' = 1 - 7 and i' = 1 - 6 are coil numbers in coil group starting from external one; 2w_c is turn number in slots completely filled with winding.

EFFECT: reduced asymmetry and scatter ratios.

1 cl, 4 dwg

Description

The invention relates to three-phase windings of electric machines of alternating current of asynchronous motors (HELL) and synchronous generators (SG).

Known two-layer loop m = 3-phase fractional windings are known, performed at 2p poles in z grooves from m′p coil groups with equal-step or concentric coils with an average pitch of grooves y _to ≈z / 2p, the number of grooves per pole and phase q = z / m′p = b + c / d, where m ′ = 2m = 6 or m ′ = m = 3 is the number of phase zones per pair of poles, c / d <1; according to symmetry conditions, the 2p / d ratios are integer, d / m are not integer [Voldek AI Electric cars. L .: Energy, 1978, S. 392-394].

Grouping coils in groups of fractional asymmetric (d / m - integer) windings are given in rows and depend on c / d [Livshits-Garik M. Windings of AC machines / Per. from English L .: SEI, 1959, p. 254], for example 7 6 6 6 6 7 6 7 6 for q = 19/3; Due to phase asymmetry, differential scattering increases.

The invention is famous for the task of reducing the asymmetry coefficients, differential scattering of an asymmetric m ′ = 3-zone winding at q = 19/3.

The solution of this problem is achieved by the fact that for m = 3-phase asymmetric fractional winding at 2р = 6 with poles in z = 57 with grooves, a two-layer m ′ = 3-zone with the number of grooves per pole and phase q = z / 3р = 19/3 of 3p with coil groups 1G ... 9G with a group of 7 6 6 6 6 7 6 7 6, repeated with time:

concentric coils have _groove steps y _Pi = 15-2 (i-1) with the number of turns (1-x) w _{to the} coils with i = 1.7 and (1 + x) w _{to the} coils with i = 4 for groups of seven-coil 1Г, 6Г, 8Г, y ′ _Пi = 14-2 (i′-1) with the number of turns (1 + x) w _{to the} coils with i ′ = 3 for all six-coil groups with (1) w _{to the} turns of coils with i ′ = 6 groups 3G, 4G, 7G, 9G, and for groups 2G, 5G with y _П = 9- (1-x) w _{to the} coil turns with i ′ = 6 in 2G and with i ′ = 1 in 5G at w _to in the remaining coils of the groups, where c = 1, 2, 3, ..., i = 1 ... 7 and i = 1 ... 6 are the numbers of coils in the groups, starting from the outer, x = 0.55 , and 2w _to - the number of turns of the grooves, completely filled with a winding.

Figure 1 shows a scan of the groove layers of the proposed winding with c = 1, 2p = 6, z = 57 with numbers 1 ... 57 from below, 3p = 9 groups with numbers 1G ... 9G from above, alternating phase zones A-B - From the upper, XYZ lower layers and the blackened grooves contain (2) w _to turns at 2w _to turns in the remaining grooves, and the shifts of the axes of the groups are marked from below; figure 2 is a diagram of the shifts of groups, their EMF phases E _A , E _B , E _With respect to the axis of symmetry 8G; figure 3, 4 on a triangular grid constructed polygons of the MDS winding for the coils is equal to - figure 3 and not equal to figure 4.

The winding of Fig. 1 is connected with series-consonant inclusion of groups 1G, 4G, 7G in phase I, 2G, 5G, 8G in phase II, 3G, 6G, 9G in phase III with beginnings of 1G, 2G, 3G; phases can mate in Y and Δ. With c = 2, 3, ... the winding has 2p = 6s = 12, 18, ... poles, z = 57c = 114, 171, ... grooves and 3pc = 18, 27, ... groups.

D=

, K_нес%=(F/D) [Петров Г.Н. Электрические машины, ч.2. Асинхронные и синхронные машины. М.-Л.: ГЭИ, 1963, C.162] вычисляется коэффициент несимметрии К_нес%=0,39% при К_об=(Е_АС+2Е_ВА)/

·57=0,8213.For the winding of Fig. 1, EMF groups are determined by the shortening coefficients of concentric coils K _yi = sin (90y _Pi / τ _P ) = sin (180 ° at _Pi / 19) with pole division τ _P = z / 2p = 9.5: K _yi = (1-x) 0.614213 (for _Pi = 15), (1 + x) 0.996585 (for _Pi = 9), (1-x) 0.47595 (y _Pi = 3) for E _gb = 5.54481-x0.093576 for groups of seven-coil (large), (1 + х) 0.996585 (y ′ _Пi = 10), (1-х) 0.614213 (y ′ _Пi = 4) at Е _{т. m} = 5.068861 + х0.329586 of groups 3G, 4G, 7G, 9G of six-coil (small). The diagram of Fig. 2 is constructed for 2p = 6, z = 57. α _П = 360 ° / z = 120 ° / 19 and the angles of shift of the axes of the groups of Fig. 1: 8Г → 9Г = 6,5α _П р = 120 ° + 0,5α _П and 8Г → 7Г = 240 ° -0,5α _P ; 8Г → 1Г = 13α _П р = 240 ° + α _П and 8Г → 6Г = 120 ° -α _П ; 8G → 2G = 19.5α _P p = 360 ° + 1.5α _P and 8G → 5G = 360 ° -1.5α _P ; 8G → 3G = 25.5α _P p = 120 ° + 0.5α _P ; and 8G → 4G = 240 ° = 0.5α _P , according to which E _B = E _{8G (b)} + 2E _{2G (m)} cos1.5α _P = 15.544266 + x0.78225 is a vertical vector, where for non-concentric groups 2G 5G-2x [cos1.5α _P -cos (1.5-2.5-3) α _P ] = x0.875825; E ² _A = (2E _{4G (m)} ) ² + E ² _{1G (b)} -4E _{4G (m)} E _{1G (b)} cos (180 ° -1.5α _П ) - by the cosine theorem and for x = 0- E _A -E _C = 15,6336, the angle γ in (2) is defined by the sine theorem 2E _4D / sinγ = E _A / sin (180 ° -1,5α _n), where γ = 6.1270 ° and then the angles of phase EMF shifts are equal to φ _BA = φ _BC = 120 ° -α _П + γ = 119.8112 and φ _AC = 120.3776 °. From the phase EMF and the shift angles, the linear EMF a = E _BA = b = E _BC = 26.9751, c = E _AC = 27.1295, and then from the expressions S = a + b + c, A = (a ² + b ² + s ² ) / 6, B =

D =

, K _carried% = (F / D) [Petrov G.N. Electric cars, part 2. Asynchronous and synchronous machines. M.-L.: SEI, 1963, C.162] the coefficient of asymmetry is calculated K _carried% = 0.39% at K _about = (E _AC + 2E _VA ) /

57 = 0.8213.

(z-3x)=0,8626 и z′=57-3x=55,5 - эквивалентное число полностью заполненных обмоткой пазов, т.е. она имеет больший К_об и меньший К_нес% (в 0,39/0,17=2,3 раза).Similarly, for the non-uniform winding of FIG. 1 at x = 0.5: E _B = 15.9354, E _A = E _C = 15.9688, γ = 6.225 °, φ _VA = φ _BC = 119.9092 °, φ _AC = 120.1816 °, a = E _BA = b = E _BC = 27.6172, c = E _AC = 27.6840, K _carried% = 0.17, K _rev = (E _AC + 2E _VA )

(z-3x) = 0.8626 and z ′ = 57-3x = 55.5 is the equivalent number of grooves completely filled by the winding, i.e. it has a larger K _about and a smaller K _carried% (0.39 / 0.17 = 2.3 times).

From the MDS polygons of Figs. 3, 4 (with unit current vectors of phase zones A-Z-B-X-C-Y in the center) according to a triangular grid and the relations

the differential scattering coefficient σ _D% is determined, which characterizes the quality of the winding but the harmonic composition of the MDS with the square of the average radius j = 1 ... z of the groove points R ² _d , the radius R _{o of the} circle for the main harmonic Determination and optimization of the parameters of three-phase windings along MDS polygons // Electricity. 1997, No. 9, p. 53-55]:

According to (1) - (2) at x = 0, K _rev = 0.8213-R ² _d = 1458/57, R _o = 57 · 0.8213 / 3π and σ _D% = 3.69; at x = 0.5 and K _rev = 0.8626-R ² _d = 1499.25 / 57, R _o = 55.5 · 0.8626 / 3π, σ _D% = 1.94%, i.e. σ _D% decreases 3.69 / 1.94 = 1.90 times. Given the changes K _about , K _carried% , σ _{d%, the} winding of Fig. 1 with x = 0.5 has a high efficiency K _eff = (0.8626 / 0.8213) (0.39 / 0.17) (3 , 69 / 1.94) (55.5 / 57) = 4.54, and with the value x = x _opt = 0.55, the parameters improve: K _rev = 0.86683, K _carried = 0.126, σ _D% = 1 88 and K _eff = 6.23.

The proposed m = 3-zone winding, in comparison with m = 6-zone for z = 39, 2p = 6, q = z / 6p = 19/6, for _P = 8, grouping 4 3 3 3 3 3 3 4 3 3 3 3 3 3 4 3 3 3, K _about = 0.9249, K _carried% = 0.14, σ _D% = 2.08, has reduced K _carried and δ _D with half as many groups.

Its application allows to reduce additional losses in the rotor and magnetic noise in the blood pressure with short-circuit rotor, improve the shape of the voltage curve in the SG.

Claims (1)

Three-phase asymmetric fractional winding at 2p = 6s poles in z = 57s grooves, performed by a two-layer m = 3-zone with the number of grooves per pole and phase q = z / 3p = 19/3 of 3pc coil groups 1G ... 9G with a group 7 6 6 6 6 7 6 7 6 repeated with times, characterized in that the concentric coils have _groove steps y _pi = 15-2 (i-1) and the number of turns (1-x) w _k for coils with i ′ = 1.7 and the number of turns (1 + x) w _k for coils with i = 4 in seven-coil groups 1G, 6G, 8G, _groove steps y ′ _pi = 10-2 (i′-1) and the number of turns (1 + x) w _to spool i '= 3 shestikatushechnyh in all groups, the number of turns equal to (1-x) w _k for coils with i' = 6 to tushechnyh groups 3G, 4G, 7G, 9G, and for coil groups 2G, 5G at step along the grooves at _n = 9, the number of turns equal to (1-x) w _to spool i '= 6 2r coil group and the spool i ′ = 1 in the 5G coil group, while in the other coils of the coil groups the number of turns is W _k , where c = 1, 2, 3, ..., i ′ = 1 ... 7 and i ′ = 1 .. .6 - numbers of coils in groups, starting from the outside; 2w _to - the number of turns, in the grooves, completely filled with a winding; x = 0.55.

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