A 10-pole 9-slot permanent magnet synchronous motor comprises a stator core including an annular yoke and a plurality of teeth. Each of the plurality of teeth has a winding portion around which a coil is wound. The plurality of teeth include three teeth groups. Each of the three teeth groups includes a first tooth, a second tooth, and a third tooth of the teeth group sequentially arranged in a rotational direction of a rotor and around which coils of one phase are wound. The first tooth, second tooth, and third tooth of each of the three teeth groups are sequentially arranged in the rotational direction of the rotor. A width of the winding portion of the third tooth is narrower than a rotational direction width of the winding portion of the first tooth.