Imagine my fan is spinning in my model. How will it defer in both analysis?
You're asking about the definitions of steady state and transient, or about the way the results might differ?
I think Abdul Jaafar answered the first part. The second question will no doubt depend on the motor design.
Take a simple case: a DC motor, with commutator ring. When the fan is stopped, just beginning to turn, current is running consistently through one winding. When voltage is applied to an inductor, as in this slow start phase, current flow gradually increases, just as it would through any inductor as the magnetic field is building up. Eventually current becomes limited only by the resistance of the winding.
V = L di/dt
You can see that for any V, there's nothing else to limit i over a long period of time.
So in the extreme case, say the fan is under heavy load and taking a long time to get up to speed, your transient current will be high. Individual windings are getting a chance to build up high current flow.
At steady state, instead, the commutator ring is rapidly changing which windings are fed with a voltage. So very rapidly, you apply voltage to a winding with no magnetic field, build up that field briefly, then move on to another winding, and current never has a chance to reach high values.
In general, an accelerating DC fan should draw more current than one in steady state. And conversely, a decelerating DC fan should draw less current, or at the extreme, will behave like a generator, sending power back to the power source.
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