Abstract: A rotary electric machine includes a frame; a stator whose stator-slot number Ns is 12; a rotor whose rotor-pole number Np is 8, the rotor being disposed inside the stator. The frame has a frame thickness T(?) at mechanical angle ?, with respect to a reference line that connects the inner circumferential center of the frame with an arbitrary point, other than the center, around the center that is circularly expanded in a Fourier series. The difference between the stator-slot number Ns and the rotor-pole number Np is k (=|Ns?Np|).

Abstract: A rotary electric machine includes a frame; a stator whose stator-slot number Ns is 12; a rotor whose rotor-pole number Np is 8, the rotor being disposed inside the stator. The frame has a frame thickness T(?) at mechanical angle ?, with respect to a reference line that connects the inner circumferential center of the frame with an arbitrary point, other than the center, around the center that is circularly expanded in a Fourier series. The difference between the stator-slot number Ns and the rotor-pole number Np is k (=|Ns?Np|). Stress-relieving spaces are located in portions of the frame in an arrangement that does not have 90-degree mechanical angle rotational symmetry, in such a way that the sum P of inclusion ratios for the k-th component Tk and the Np-th component TNp, which are the Fourier series expansion coefficients for the frame thickness T(?) expressed by equation (2). P = ( T k + T N ? ? p ) / ? n = 0 ? ? T n × 100 ? [ % ] ( 2 ) , is less than 12%.