ASYMMETRIC THREE-PHASE FRACTIONAL-SLOT WINDING WITH 2p = 6c POLES PLACED IN z = 39c 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 double-layer fractional-slot winding with m = 3 phases, m' = m = 3 bands, 2p = 6c poles in z = 39c slots, and slot number per pole per phase q = z/3p = 13/3 has 3pc coil groups with coil grouping 5 4 4 4 4 5 4 5 4 repeated c times. Novelty is that slot pitches of concentric coils y_si = 10 - 2(i - 1) and turn numbers (1 - x)w_c for coils with i' = 1, 5 and turn number (1 + x)w_c for coil with i' = 3 in five-coil groups 1G, 6G, 9G; slot pitches y'_si = 9 - 2(i' - 1) and turn number (1 + x)w_c for coil with i' = 2 in all four-coil groups; turn number equals (1 - x)w_c for coil with i = 4 in coil groups 3G, 4G, 7G, 9G, and for coil groups 2G, 5 G at slot pitch y_si = 6 turn number equals (1 - x)w_c for coil with i = 4 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 - 5 and i' = 1 -4 are coil numbers in coil groups starting from external one; w_c is turn number in slots completely filled with winding.

EFFECT: reduced asymmetry and differential scatter ratios.

1 cl