Permanent magnet rotor of an electrical machine

A rotor includes a rotor core; and first permanent magnets and second permanent magnets arranged in the rotor core so that, on a cross-sectional plane of the rotor core perpendicular to the rotation axis thereof, the first and second magnets corresponding to each other define the letter V having an apex pointing toward the rotation axis. The first and second magnets corresponding to each other are arranged so that a straight line interconnecting the rotation axis and the apex of the letter V is interposed therebetween, an angle of the first magnet relative to the straight line being smaller than that of the second magnet relative to the straight line, a width of the first magnet in the direction parallel to the first side of the letter V being smaller than that of the second magnet in the direction parallel to the second side of the letter V.