Three phase induction motors employ a simple construction made up of a stator covered with electromagnets, and a rotor composed of conductors shorted at each end, arranged as a “squirrel cage”. They work on the theory of induction in which a rotating electro-Induction Motor china magnetic field it produced through the use of a three-phase current at the stators electromagnets. Therefore induces a current in the rotor’s conductors, which in turns generates rotor’s magnetic field that attempts to check out stator’s magnetic field, pulling the rotor into rotation.
Great things about AC Induction Motors are:
Induction motors are basic and rugged in building. They are more robust and can operate in any environmental condition
Induction motors are cheaper in expense due to simple rotor construction, absence of brushes, commutators, and slip rings
They are free of maintenance motors unlike dc motors because of the absence of brushes, commutators and slip rings
Induction motors could be operated in polluted and explosive environments as they do not have brushes that may cause sparks
AC Induction motors are Asynchronous Machines meaning that the rotor will not change at the precise same speed since the stator’s rotating magnetic field. Some difference in the rotor and stator quickness is necessary in order to make the induction into the rotor. The difference between the two is named the slip. Slip must be kept within an optimal range to ensure that the motor to operate effectively. Roboteq AC Induction controllers can be configured to operate in one of three modes:
Scallar (or Volts per Hertz): an Open up loop mode where a control causes a simultaneous, fixed-ratio Frequency and Voltage modify.
Controlled Slip: a Shut Loop speed where voltage and frequency are managed in order to keep slip inside a narrow range while running at a preferred speed.
Field Oriented Control (Vector Drive): a Closed Loop Quickness 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 about how AC Induction Motors are constructed and work.