The present invention provides a dynamoelectric machine that can reduce 12f vibrational force and suppress generation of irritating electromagnetic noise in a vicinity of 2,000 Hz in an idling state. In the present invention, an armature winding includes first and second three-phase windings, the first three-phase winding is configured by delta-connecting respective phase windings, and the second three-phase winding is configured so as to be Y-connected to the first three-phase winding by connecting respective phase windings in series to respective output ends of the first three-phase winding. The first and second three-phase windings are each installed in the stator core such that respective phase currents have a phase difference from each other. In addition, angles between center lines of adjacent slot opening portions of the stator core central angles of adjacent slot opening portions of the stator have a nonuniform pitch, and a turn ratio between the first three-phase winding and the second three-phase winding is within a range of 1.25 to 2.25.