A stator winding of an alternator has two poly-phase windings. Each of phase coils, e.g., X-phase coil in one of poly-phase windings, is provided by a continuous wire. The phase coil is accommodated in corresponding slots in a layered manner along a radial direction, therefore, the phase coil forms layers in the slots and may be identified as location of layers in the slots. The phase coil has a plurality of crossing portion that links the layers in different slots distanced by a magnetic pole pitch, and two output portions extending beyond the stator winding. In the phase coil, only one crossing portion is formed to link the same layers in different slots, and the other crossing portions are formed to link different layers in different slots.