Six single phase winding portions are installed in slots disposed at a ratio of two per phase per pole. Each single-phase winding portion has two wave windings formed by winding a conductor wire for a predetermined number of winds into a wave-shaped pattern composed of slot-housed portions disposed at a pitch of six slots in a circumferential direction and crossover portions linking together end portions of adjacent pairs of the slot-housed portions alternately relative to an axial direction, the wave windings being offset by six slots from each other circumferentially and installed in the slots such that the crossover portions face each other axially.