The AC Induction Motor (ACIM), sometimes called a squirrel cage motor, is among the most popular motors found in consumer and commercial applications. Induction machines are by much the biggest group of all commercial electrical machines, converting around 70-80% of all electrical energy into mechanical form. The have a very robust rotor construction, which makes them suitable for high-speed applications. With correct design, they have good overloading and field weakening characteristics.

The ACIM is made up of a simple cage-like rotor and a stator containing three windings

The changing field produced by the AC line current in the stator induces a current in the rotor which interacts with the field and causes the rotor to rotate

The rotor does not have any moving contacts, which eliminates sparking