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, 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.