Patent ID: 8030817

Claim:
A rotor of a permanent-magnet-type rotating electrical machine, comprising: a plurality of first permanent magnets and second permanent magnets arranged in point symmetry with respect to a rotation center of the rotor and imbedded in a rotor core alternately along a rotational direction of the rotor, the first permanent magnets having a magnetic characteristic of being relatively more easily magnetized by a magnetic field created by a d-axis current flowing through an armature coil, the second permanent magnets having a magnetic characteristic of being relatively less easily magnetized than the first permanent magnets by the magnetic field and having a larger coercive force than a coercive force of the first permanent magnets, the plurality of first permanent magnets and second permanent magnets to form a plurality of magnetic poles around a rotational axis with each second permanent magnet and two first permanent magnets each neighboring the second permanent magnet, and at each magnetic pole, the first permanent magnets are magnetized by the magnetic field created by a d-axis pulse that is greater than a usual current flowing through the armature coil during a normal operation, to irreversibly change a magnetic force of the first permanent magnets and maintain the changed magnetic force while not to irreversibly change a magnetic force of the second permanent magnets.