Armature winding of rotating electrical machine

According to one embodiment, there is provided a 3-phase even-numbered-pole 2-layered armature winding housed in 45 slots per pole provided in a laminated iron core. In each coil piece group of each phase belt, the coil pieces of the second and fifth parallel circuits are placed in the second positions from the pole center among three positions of coil pieces in corresponding coil piece group. In six or four groups out of ten coil piece groups of each phase belt, coil pieces of the first or fourth parallel circuit are placed in the first position from the pole center. In first and second coil piece groups, coil pieces of the first or fourth parallel circuit are placed in different-numbered positions from the pole center.