Compared with traditional motors, Halbach motors have the following advantages:
Compared with the traditional permanent magnet motor architecture, due to the overlapping of the parallel magnetic field and the radial magnetic field after the decomposition of the Halbach magnetic ring, the magnetic field strength on the other side is greatly increased, which can effectively reduce the volume of the motor and improve the power density of the motor.
In the traditional permanent magnet motor, due to the inevitable harmonics of the air gap magnetic field, a chute is generally adopted on the fixed rotor structure to reduce its influence. In Halbach motor, because the sinusoidal distribution of the air gap magnetic field is high, the harmonic content is small, so the rotor does not need a chute.
Due to the unilateral magnetic field distribution generated by the Halbach magnet self-shielding effect, the rotor no longer needs to use magnetic materials to provide a path, which not only provides a larger selection space for the rotor material selection, but also enables the system to have lower moment of inertia and better rapid adhesion performance.
Folding permanent magnet
As a result of the magnetization of the Halbach magnet, the working point of the permanent magnet is higher, generally more than 0.9, which improves the utilization rate of the permanent magnet.
Folded central winding
Distributed winding is often used in traditional permanent magnet motors to weaken the influence of harmonic magnetomotive force. Because the sinusoidal distribution of the magnetic field in Halbach motor is high and the influence of the harmonic magnetic field is small, the centralized winding can be used.
The use of Halbach motor magnet arrangement can reduce the torque ripple of the motor, so the bearing requirements of the motor are greatly reduced.
Radial magnet arrangement magnetic field distribution
Magnetic field distribution in parallel magnet arrangement
Halbach arranged magnetic field distribution