FRACTIONAL-SLOT (Q=4/7) MULTIPHASE WINDING OF ALTERNATING-CURRENT MACHINES Russian patent published in 2004 - IPC

FIELD: electrical and electromechanical engineering.

SUBSTANCE: proposed winding is intended for use in twelve-phase squirrel-cage induction motors of variable-speed ac drives supplied with power from semiconductor frequency changer. It is double layer m = 12-phase fractional-slot lap winding with q = 4/5 per pole per phase, p = 7 and 2p = 14 poles placed in z = 12pq = 48 slots that incorporates provision for eliminating most pronounced fractional harmonic component and has K = 48 coils numbered 1K through 48K with slot pitch y_s grouped in r4ange 1 1 0 1 0 1 0. Each of coils 1K + 4(c) and 2K + 4(c) has (1 - x)w_c turns and each of coils 3K + 4(c) and 4K + 4(c), (1 + x)w_c turns. Cumulatively connected in series in first phase are coils 1K, *K, 15K, and 22K, their phase starts running from start of 1K and finish, from finish of 22K; coils of each next phase are alternating at interval of 28 numbers within K = 48 relative to coils of first phase, where y_s = 2; 2w_c is turn number in each phase; x = 12, and value of c in coil numbers varies between 0 and 11.

EFFECT: reduced differential dissipation.

1 cl, 3 dwg