NINE-PHASE FRACTIONAL(q=3/4) WINDING OF A C ELECTRIC MACHINE Russian patent published in 2004 - IPC

FIELD: electrical engineering, electric machine building. SUBSTANCE: invention is related to nine-phase asynchronous motors with squirrel-cage rotors fed from semiconductor frequency converters in A C frequency-controlled drives. Technical result consists in manufacture of double-layer m= 9-phase, m'= 18-zone fractional 2p=8-pole winding dropped in z=18pq=54 slots and with number of poles q=3/4 per pole and phase with elimination of most strongly expressed harmonic of fractional order from its magnetomotive force to diminish differential dispersion. Winding is double-layer 2p=8-pole with number of slots q=3/4 per pole and phase and row grouping 1 1 1 0 in z=54 slots in K= 54, coils with numbers from 1K to 54K and slot pitch y_s. With number of phases m=9, phase zones m'=2m=18 coils 1K+3(k) and 3K+3(k) have W_c turns and coils 2K+3(k) haves (1-x)W_c turns. In first phase coils 1K,- 8K, 15K, 28K, -35K,42K are connected in series with start of phase from start of 1K and its finish from finish 42K and coils of each next phase alternate with interval of 15 numbers within limits K=54 coils relative to coils of first phase, where y_s, 2w_c are numbers of turns in completely filled slot, x= 0.21, value k in numbers of coils varies in limits from 0 to 2m-1=17 and sign (-) by number of coil signifies its opposite connection in phase. EFFECT: manufacture of nine-phase fractional winding with diminished differential dispersion. 3 dwg