Stator yoke-free axial flux permanent magnet motor

Abstract

The invention discloses a stator yoke-free axial flux permanent magnet motor comprising a stator, a first rotor and a second rotor which are coaxial. The first rotor and the second rotor are symmetrically arranged on the two sides of the stator. The first rotor and the second rotor respectively comprise a hollow annular first rotor core and a second rotor core which are used for coaxially connecting with a rotating shaft. The first rotor core and the second rotor core are alternately provided with permanent magnets and soft magnets along the circumference toward the end face of the stator. Theratio of the pole-arc coefficient of the permanent magnets to the soft magnets is greater than 1. The permanent magnets and the soft magnets on the different rotors of the two sides of the stator arearranged diagonally. According to the stator yoke-free axial flux permanent magnet motor, the flux weakening capability and the utilization ratio of the permanent magnets can be enhanced, the coggingtorque and the axial magnetic tension can be reduced and the bearing of the motor can be protected to a certain extent by using the diagonal alternating rotor structure with unequal pole-arc coefficient.

Description

technical field [0001] The invention relates to the technical field of motors, in particular to a stator-yokeless axial flux permanent magnet motor. Background technique [0002] The stator yokeless axial flux motor is a kind of permanent magnet motor, which has the advantages of small size, high power density and high efficiency. However, the traditional stator yokeless axial flux motor has problems such as insufficient field weakening capability (narrow speed range) and large cogging torque, which affects the field weakening and speed expansion capability of this type of motor in the speed control system. Positioning accuracy in position control systems. [0003] Approximate methods for reducing motor cogging torque and improving field weakening capability currently exist include the method of using permanent magnet oblique poles and the method of using permanent magnet built-in and alternating pole structure. However, while the above method can improve the field weakeni...

AI Technical Summary

Problems solved by technology

However, while the above method improves the field weakening capability and reduces the cogging torque to a certain extent, it will affect other performances of the motor

The method of using the oblique pole of the permanent magnet reduces the cogging torque and also weakens the torque output capability, resulting in a decrease in the utilization rate of the permanent magnet; the method of using the built-in permanent magnet improves the magnetic field weakening capability and at the same time reduces the mechanical strength of the motor. Poor, the flux leakage of the permanent magnet increases (the utilization rate of the permanent magnet decreases)

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