SQUIRREL-CAGE INDUCTION MOTOR
Rotor view
In the rotor reference frame, the rotor speed ωm is effectively zero. The flux density wave represented by the space vector Bm (or, equivalently, by the magnetizing current Im) now moves at slip speed with respect to the rotor inducing in the rotor bar slip-frequency currents which are sinusoidally distributed. The result is seen as a sinusoidally distributed rotor winding whose axis is represented by the space vector Ir; both winding and space vector Ir rotate at the slip speed ωsl . Similarly, the stator space vector IR which compensates for the rotor effects and the resultant stator current Is = IR + Im all move at slip speed.