China Neodymium And Ferrite Magnets Manufacturer & Supplier 
When many people hear the term ‘three-phase motor’, their first thought might be that they all contain magnets. But is that really the case?
In fact, not all three-phase motors use permanent magnets. ‘Three-phase motor’ is a general term for a broad category of motors, which primarily includes different types such as three-phase induction motors and three-phase permanent magnet synchronous motors; only three-phase permanent magnet synchronous motors incorporate magnets.
Ordinary three-phase asynchronous motors do not have permanent magnets inside, because these motors mainly rely on the stator winding to generate a rotating magnetic field after passing three-phase AC power, and then use electromagnetic induction to generate current in the rotor, forming a rotor magnetic field to achieve motor rotation. Its rotor generally adopts a squirrel cage structure composed of stacked silicon steel sheets and aluminum or copper bars, and does not require the installation of magnetic steel.
The accompanying image shows a ferrite rotor magnet for an electric motor.
In a three-phase permanent magnet synchronous motor, permanent magnet materials such as neodymium-iron-boron magnets, samarium-cobalt magnets or ferrite magnets are mounted on the rotor. These magnets generate a stable magnetic field which interacts with the rotating magnetic field produced by the stator, causing the rotor to rotate in synchronisation. Compared with conventional asynchronous motors, permanent magnet synchronous motors are characterised by high efficiency, compact size and rapid response; they are currently widely used in products such as drive motors for new energy vehicles, industrial servo motors, robots, power tools and high-performance fans.
There are many different shapes of magnets used in three-phase permanent magnet motors, such as the common wafer-shaped magnets, rectangular magnets and ring magnets. Depending on the motor design, the magnets may be mounted on the surface of the rotor or embedded within the rotor core. For new energy vehicles and high-performance motors, high-performance sintered neodymium-iron-boron magnets are typically used, as they possess a high magnetic energy product and a strong magnetic field, which helps the motor achieve higher power density.
The above provides an overview of whether magnets are present inside three-phase motors. Should your company require samples of magnets for motors, sensors or encoders, or wish to enquire about pricing, please do not hesitate to contact us.
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