Patent ID: 8664820

Claim:
An electric motor-driven compressor comprising: an electric motor including a stator, which has a cylindrical shape and an inner part perforated in an axial direction and is provided in an internal circumferential surface thereof with a plurality of winding slots extending in parallel to the axial direction such that a coil is wound therein and a rotor having the cylindrical shape and coaxially provided in the stator, wherein six permanent magnets are inserted into the rotor in the axial direction, and twenty-seven winding slots are provided along the internal circumferential surface of the stator at a regular interval, wherein an angle formed by two straight lines passing through a center of the rotor and making contact with both end portions of one permanent magnet adjacent to the center of the rotor is in a range of about 48.7° to about 51°, and wherein a ratio of a shortest distance, which is measured from the center of the rotor to each permanent magnet, to the radius of the rotor, is in a range of about 0.74 to about 0.78.