According to one embodiment, there is provided a three-phase even-numbered-pole two-layered armature winding housed in forty five slots per pole provided in a laminated iron core. Coil pieces corresponding to first and second parallel circuits are arranged in the first phase belt (17), coil pieces corresponding to fourth and fifth parallel circuits are arranged in the second phase belt (18), coil pieces corresponding to the third parallel circuit are arranged in the first and second phase belts (17, 18), and the upper coil pieces (15) and the lower coil pieces (16) of each parallel circuit are placed in same-numbered positions from a pole center.