Ac motor is divided into synchronous and asynchronous motors, synchronous is mainly used as a generator, asynchronous is mainly a motor. Mainly talk about asynchronous motor, asynchronous motor has been widely used because of its simple structure, cheap price, convenient maintenance, reliable operation and other characteristics.
Although the AC motor structure is simple, but the working principle is actually a little more complex than DC, if you want to understand clearly also more laborious.
Three phases of symmetrical alternating current are applied to the stator of the AC motor, as shown in the figure above. The stator does not move, but only by changing the current, a rotating synthetic magnetic field can be generated, which is like a magnet rotating around the stator.
With this rotating magnet, everything is easy to do, put a closed coil inside the stator, in this closed coil will be induced electromotive force and current, will produce electromagnetic force, closed coil will rotate.
It can also be understood that the stator has a rotating magnet, the rotor closed coil due to induction charged, in fact, also becomes an electromagnet, the outside electromagnet in the turn, will take the inside electromagnet turn, so the rotor of the AC motor will turn up.
The rotating speed of the stator magnetic field is called synchronous speed. The rotor inside is actually driven by the stator magnetic field, so its speed will be slower than the speed of the stator magnetic field, so it is called asynchronous speed. Hence the name asynchronous motor.
The rotor of AC motor is so simple a few closed coils, or closed conductors, like a rat cage, so it is also called squirrel cage asynchronous motor.
In addition, because the electromotive force and current inside the rotor are induced by the stator magnetic field, so the induction motor is called induction motor. So the name of the three-phase AC series motor is more: AC motor, induction motor, induction motor, are saying it, from a different Angle to give it the name.
Ac motor under the synchronous, asynchronous said:
Synchronization: permanent magnet synchronous motor (currently the mainstream of electric vehicles, but not Tesla), reluctance synchronous motor and hysteresis synchronous motor. Synchronous motors are generally used as generators.
Asynchronous: induction motor, AC commutator motor.
Induction motor: three-phase asynchronous motor, single-phase asynchronous motor, covered pole asynchronous motor, etc.
Ac commutator motor: single-phase series motor, repulsion motor.
