Squirrel-cage rotor of an induction motor (developed view)
Developed view of a squirrel-cage rotor in a 2-pole field in the rotor
reference frame: The sinusoidally distributed flux
density wave is moving at slip speed ωslip inducing in the rotor cage
voltages proportionall to slip speed and corresponding value of the flux density
(in accordance with Faraday's Blu
rule). Assuming that the rotor is purely resistive, currents will be produced in
phase with the induced voltages. These bar currents are shown in the simulation
together with the corresponding rotor-mmf distribution.
Note that the resultant flux density wave is 90o ahead of the rotor
mmf wave. The electromagnetic torque acting on the rotor is directed to the
right.
M. Riaz, Created with GeoGebra |