According to the structure of the rotor, it can be divided into: cage induction motor (the old standard is called squirrel cage asynchronous motor) and wound rotor induction motor (the old standard is called wound asynchronous motor).
According to the operating speed, it can be divided into high-speed motors, low-speed motors, constant-speed motors, and speed-regulating motors. Low-speed motors are further divided into gear reduction motors, electromagnetic reduction motors, torque motors and claw pole synchronous motors.
In addition to stepless constant speed motors, stepless constant speed motors, stepless variable speed motors and stepless variable speed motors, speed regulating motors can also be divided into electromagnetic speed regulating motors, DC speed regulating motors, PWM variable frequency speed regulating motors and Switched reluctance speed motor.
The rotor speed of an asynchronous motor is always slightly lower than the synchronous speed of the rotating field.
The rotor speed of the synchronous motor has nothing to do with the size of the load and always maintains a synchronous speed.