DESIGN OF THE BALANCED THREE PHASE A.C. WINDINGS FOR SMALL POWER INDUCTION MOTORS

摘要

The three-phase a.c. windings are approached in the paper taking into account the supplementary degree of freedom given by non-uniform distribution of the coils placed in the non-equal cross section slots. A functional criterion is defined starting from the space harmonic contents of the air gap mmf expressed by the number of turns of the. stator concentric coils and the angular openings of the respective coils. Some constraints related to the technological limitation such as minimum tooth width and minimum yoke height are considered. One example of the single layer, fractional winding with 1.5 slots per pole and phase is presented and discussed.