ELECTRICAL-MACHINE THREE-PHASE DOUBLE-LAYER FRACTIONAL-PITCH (q=2.25)WINDING Russian patent published in 2006 - IPC H02K3/04 H02K3/28 

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

SUBSTANCE: proposed three-phase double-layer fractional-pitch (q = 2/25) winding is 2p = 8c-pole winding grouped in row 3 2 2 2 in z= 27c slots made of 12c coil groups numbered 1G through 12(c)G with concentric coils at mean slot pitch y_s = 3, integer number c = 1, 2 ..., and slot turns 2w_c. Novelty is that in order to reduce differential dissipation σ_d of electrical-machine m' = three-band fractional-pitch (q = z/3p = 2/25) winding, three-coil group 1G out of first-grouping coil groups 1G through 4G has coil pitch y_m = 5, 3, 1 with turn numbers (1 - x)w_c, w_c, (1 - x)w_c, and single-coil ones have y_s = 4.2 with turn numbers (1 + x)w_c, w_c, in group 3G at w_c turns in remaining coil groups, mentioned distribution of coils with unequal turn number being repeated in each next grouping, where x = 0.43.

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

1 cl, 3 dwg