Section 15.1: Operation of a Three-Phase Induction Motor cont.
The stator’s rotating field cuts the rotors conductors thereby inducing three-phase voltages in the rotor circuit
The three-phase induced (Faraday) voltages cause three-phase currents to flow in the rotor
The rotor’s three-phase currents produce a rotating (rotor) field which is always aligned (travels with) the stator’s rotating field
The whole process is essentially that of a transformer
Ergo, the induction motor is sometimes referred to, in the vernacular, as a rotating transformer
The rotor structure chases the rotating stator field¾but can never catch up to it because of electrical friction (rotor resistance)