ASYMMETRIC THREE-PHASE SLOT-PITCH WINDING WITH 2p = 6c POLES IN z = 21c SLOTS Russian patent published in 2007 - IPC H02K3/04 H02K3/28 

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

SUBSTANCE: proposed m = 3-phase, m' = m = 3-band double-layer fractional-slot lap winding placed in z= 21c slots, with slot number per pole per phase q = z/3p = 7/3 is assembled of 3pc coil groups 1G through 9G with coil grouping 3 2 2 2 2 3 2 3 2 repeated c times. Novelty is that concentric windings have slot pitches y_si = 5, 3, 1 and turn numbers (1 - x)w_c, (1 + x)w_c, (1 - x)w_c for three-coil groups 1G, 6G, 8G, respectively, slot pitches y_si = 4, 4 and turn numbers (1 + x)w_c, (1 - x)w_c, respectively, for two-coil groups 3G, 4G, 7G, 9G, and for coil groups 2G, 5G at slot pitch y_s = 3 turn numbers equal (1 - x)w_c (1 - x)w_c in coil group 2G, coil turn numbers equal (1 - x)w_c, (1 - x(1 - x)w_c in coil group 5G; turn number in remaining coils of coil groups equals w_c, where c = 1, 2, 3, ...; 2w_c is turn number in slots completely filled with winding; x = 0.6.

EFFECT: reduced asymmetry and differential scatter ratios.

1 cl, 4 dwg