A rotor (21) is an interior permanent magnet rotor formed of a rotor core (24) in which a plurality of permanent magnets (25) are embedded at predetermined intervals. First protruding portions (26) and second protruding portions (27) are formed on an outer peripheral face of the rotor, the first protruding portions (26) each opposing the vicinity of a central portion of each of the permanent magnets and having a substantially arc-shaped cross section protruding outward and the second protruding portions (27) each opposing the vicinity of an end portion of each of the permanent magnets and protruding outward. One first protruding portion and two second protruding portions correspond to one permanent magnet. The formation of the first and second protruding portions as described above on the outer peripheral face of the rotor makes it possible to sufficiently reduce the torque ripple and the noise caused by the distortion of air-gap magnetic flux distribution.