THREE-PHASE FRACTIONAL-SLOT WINDING Russian patent published in 1997 - IPC

FIELD: ac machines. SUBSTANCE: three-phase fractional-slot (q=3.125) winding is placed in Z=75p/4 slots and has 6p coil groups numbered in phases 1G+3k, 9G+3k, 17G+3k; coils are grouped in row 4,3,3,3,3,3,3,3,3 repeated 3p/4 times; groups numbered 1G+3k have four concentric coils with slot pitch Ys= 10, 8, 6, 4 and turn number W, W, W, (1-x)W; remaining groups have three concentric coils with slot pitch Ys=9, 7, 5 and turn number W, where p>=4 is a multiple of four, k=0,1,2,...,(2p-1), 2W is turn number per slot, and x= 0.5 chosen within 0.45<=x<=0.55. EFFECT: reduced differential dissipation. 4 dwg