**Stator view**

Three-phase sinusoidal balanced excitation in 3 stator phases produces a sinusoidally distributed field rotating at the excitation frequency ω_{s}. This field can be viewed as being created by a single equivalent sinusoidal winding which is excited with dc current and which is also rotating. The flux density distribution is represented here by the state vector B_{m} (or, equivalently, by the magnetizing current I_{m}). It is portrayed in the air gap with shaded colors for which the more intense the color the higher the field intensity and where blues point to the rotor and reds to the stator.

This distribution rotates at the stator frequency ω_{s} as seen from the stator stationary frame and at the slip frequency ω_{slip}=ω_{s}– ω_{m} with respect to the rotor turning at ω_{m}, thereby generating sinusoidal voltages of slip frequency in the rotor bars and corresponding sinusoidal slip-frequency currents with a delay due to the presence of rotor leakage. This rotor current distribution rotates at ω_{slip} with respect to the rotor and atω_{s} with respect to the stationary stator observer. It can thus be represented by the rotor space vector I_{r}. Since B_{m}_{ }(or I_{m}) cannot change, the stator current I_{s} must include a component I_{R }= – I_{r} .

**Rotor view**

In the rotor reference frame, the rotor speed ω_{m} is effectively zero. The flux density wave represented by the space vector B_{m} (or, equivalently, by the magnetizing current I_{m}) 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 I_{r}; both winding and space vector I_{r} rotate at the slip speed ω_{sl} . Similarly, the stator space vector I_{R} which compensates for the rotor effects and the resultant stator current I_{s} = I_{R} + I_{m}all move at slip speed.

**Synchronous view**

In the synchronous reference frame, all variables appear as dc quantities in steady state. All space vectors are frozen in space in the shown fixed position based on the assumption that the original stationary and the synchronously rotating reference frames coincide at time t = 0. These vectors may then be directly associated with the (per-phase) phasors of the induction motor, combined in a phasor diagram, and interpreted by means of an equivalent cicuit made up of a magnetizing inductance in parallel with the rotor leakage inductance acting in series with a resistor.

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