Permanent magnet electric motor

摘要

According to one embodiment, a rotor is configured by a rotor core and magnetic poles. Two or more types of permanent magnets are used such that each product of coercivity and thickness in the magnetization direction becomes different. A stator is located outside the rotor with air gap therebetween and configured by an armature core winding. At least one permanent magnet is magnetized by a magnetic field by a current of the armature winding to change a magnetic flux content thereof irreversibly. A short circuited coil is provided to surround a magnetic path portion of the other permanent magnet excluding the magnet changed irreversibly and a portion adjacent to the other permanent magnet where the magnetic flux leaks. A short-circuit current is generated in the short circuited coil by the magnetic flux generated by conducting a magnetization current to the winding. A magnetic field is generated by the short-circuit current.

主权项

1. A method for manufacturing a permanent magnet electric motor comprising:
disposing a plurality of magnetic poles inside a rotor core to form a rotor and skewing each position of the magnetic poles in the rotor core in a circumferential direction, the rotor core being divided into two or more core parts in an axial direction thereof, the plurality of magnetic poles being formed by two or more types of permanent magnets selected such that a product of coercivity and thickness in a magnetization direction of each magnet is different from each other; providing a conductive panel integrally-configured with conductive bars disposed on front and rear faces of the conductive panel, the conductive bars being displaced with respect to each other corresponding to a skewed angle amount of the core parts in the circumferential direction of the rotor core and protruding toward each core part in the axial direction of the rotor core; superimposing the core parts each other by placing the conductive panel therebetween in the axial direction of the rotor such that the conductive bars are inserted into short circuited coil insertion holes of the core parts and the conductive panel is disposed at a boundary part of the core parts; forming a short circuit connection part by connecting tips of the conductive bars with each other at an axial end face of each core part so as to form conductive short circuit coils generating a short-circuit current that flows in the core parts upon magnetizing the permanent magnets based on a magnetic flux generated during magnetization; and locating a stator formed by an armature core and an armature winding outside the rotor with an air gap therebetween, the armature winding generating a magnetic field which magnetizes at least one permanent magnet forming the magnetic poles of the rotor.