Three phase induction motors employ a simple construction composed of a stator covered with electromagnets, and a rotor made up of conductors shorted at each end, arranged as a “squirrel cage”. They focus on the principle of induction in which a rotating electro-magnetic field it made through the use of a three-phase current at the stators electromagnets. Therefore induces a current within the rotor’s conductors, which in turns generates rotor’s magnetic field that tries to check out stator’s magnetic field, pulling the rotor into rotation.
Benefits of AC Induction Motors are:
Induction motors are simple and rugged in Induction Motor china structure. They are more robust and can operate in any environmental condition
Induction motors are cheaper in cost due to simple rotor construction, lack of brushes, commutators, and slide rings
They are maintenance free motors unlike dc motors due to the lack of brushes, commutators and slip rings
Induction motors can be operated in polluted and explosive conditions as they do not have brushes that may cause sparks
AC Induction motors are Asynchronous Machines meaning that the rotor does not convert at the specific same speed as the stator’s rotating magnetic field. Some difference in the rotor and stator speed is necessary to be able to produce the induction into the rotor. The difference between your two is named the slip. Slip should be kept within an optimal range in order for the motor to use effectively. Roboteq AC Induction controllers could be configured to operate in one of three modes:
Scallar (or Volts per Hertz): an Open up loop mode where a order causes a simultaneous, fixed-ratio Frequency and Voltage change.
Controlled Slip: a Closed Loop speed where voltage and frequency are managed to keep slip inside a narrow range while operating at a desired speed.
Field Oriented Control (Vector Drive): a Closed Loop Velocity and Torque control that works by optimizing the rotating field of the stator vs. this of the induced field in the rotor.
Observe this video from Learning Engineering for a visual illustration on how AC Induction Motors are constructed and function.