Development of magnetic tile for permanent magnet motor

 Here are the details of the newsHere are1) Permanent magnet motor is divided into permanent magnet DC motor and permanent magnet AC motor.

1.1 Permanent magnet AC motor refers to multi-phase synchronous motor with permanent magnet rotor. Previously, ferrite and Al-Ni-Co magnetic tile were mainly used. With the increasing demand for power, the accumulation of low magnetic energy between ferrite and Al-Ni-Co cannot meet the requirement. Nowadays, Nd-Fe-B magnetic tile is widely used in the field of high-power synchronous motor and generator. Of course, Nd-Fe-B magnetic tile, because rare earth resources are precious, the price of raw materials has doubled. Its manufacturing cost and production price will continue to rise in the future, affecting its large-scale use in some low-end areas. Negative temperature coefficient and low Curie temperature of Nd-Fe-B permanent magnets also limit their application in high temperature situations.

1.2 Permanent magnet DC motor is divided into brushless motor and common DC motor with commutator. Its application situation is judged from the shape and pole number of magnet. In ordinary DC motors, 2 poles and 4 poles are the majority, and magnetic tile is basically used as motor stator. Most of micro DC motors use ferrite magnetic tile, mainly used in toys, household appliances, automotive fields. When a brushless motor uses a magnetic tile as its stator, it usually exceeds six poles, so its central angle is much smaller than that of a conventional DC motor. But when the magnetic tile is used as the rotor of brushless motor, it can have more than 4 or 6 poles. For the four poles, the rotor is magnetized on the outer surface, and its central angle is close to 90 degrees, which is different from the ordinary DC motor.

2) The magnetic tile has different requirements for its performance and magnetic field waveform according to its application field. As a rotor field, its external arc surface surface field is demanded to be high, and its waveform is basically sinusoidal. As a stator, the magnetic tile of the stator is selected according to the different requirements of the motor's output, spark and noise, and its internal arc table is made. The field height is determined by the shape and production characteristics of the magnetic tile itself. Its waveform is mainly saddle shape. This kind of waveform has great output, but spark noise and no-load current. In order to improve vibration noise, commutation spark and reduce no-load current, the shape and size of magnet steel and die design should be carefully designed. Among them, unequal thickness magnetic tile has been widely used. Its principle is to make the waveform of air gap magnetic field in the inner arc of magnetic tile tend to flat top wave. the details of the newsHere are the details of the newsHere are the details of the newsHere are the details of the newsHere are the details of the newsHere are the details of the newsHere are the details of the newsHere are the details of the newsHere are the details of the newsHere are the details of the newsHere are the details of the newsHere are the details of the newsHere are the details of the newsHere are the details of the newsHere are the details of the newsHere are the details of the newsHere are the details of the newsHere are the details of the newsHere are the details of the newsHere are the details of the newsHere are the details of the newsHere are the details of the newsHere are the details of the newsHere are the details of the newsHere are the details of the newsHere are the details of the newsHere are the details of the newsHere are the details of the newsHere are the details of the news