Variable flux permanent magnet synchronous motor

Abstract

The invention relates to a motor, in particular to a permanent magnet synchronous motor with variable magnetic flux, which has the advantages of easy magnetic field adjusting, high efficiency and wide speed regulation range. The motor comprises a stator consisting of an iron core (1) and an armature winding (2), and a rotor consisting of NdFeB permanent magnet (3), AINiCo permanent magnet (4), soft iron (5), a non-magnetic interlayer (6), a non-magnetic shaft (7), etc. Each permanent magnet in the rotor is composed of two different magnets stacked on each other and tangentially magnetized. The AlNiCo permanent magnet is ladder-shaped and close to the shaft, and the NdFeB permanent magnet is rectangular-shapee and close to an air gap. The non-magnetic interlayer in the rotor is triangular-shaped and connected with the permanent magnet at a section close to the shaft. The entire rotor is packaged by a cylinder with staggered magnetic and non-magnetic regions. The magnetization state of the AlNiCo permanent magnet can be changed by applying a pulse current id to the straight shaft of the stator, thus achieving effectively the adjustment of air-gap magnetic field of the motor.

Description

technical field [0001] The invention relates to a motor, in particular to a permanent magnet synchronous motor with controllable magnetic flux. Background technique [0002] The traditional permanent magnet motor has the limitation that the air gap magnetic field is not easy to adjust, and it is difficult to achieve wide speed regulation, which affects its application range. In order to expand the speed regulation range of permanent magnet motors, most of the traditional methods adopt vector control strategy, which weakens the permanent magnet magnetic field by controlling the direct-axis armature reaction magnetic field generated by the stator current vector, maintains the balance of the motor voltage during high-speed operation, and achieves magnetic field weakening. purpose of speed. Since there are permanent magnets with large reluctance on the direct axis, the inductance of the direct axis is generally low, so that the direct-axis armature reaction flux generated by th...

AI Technical Summary

Problems solved by technology

Since there are permanent magnets with large reluctance on the direct axis, the inductance of the direct axis is generally low, so that the direct-axis armature reaction flux generated by the rated current of the motor can only weaken a very small part of the permanent magnet flux, so that the motor The weakening effect of the magnetic field is not good, and it is difficult to adjust the magnetic field

And adopting such a field weakening method needs to apply a continuous large stator direct axis current, which increases the copper loss of the motor and reduces the efficiency

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