Hello

I am currently doing an experiment for an 3 phase induction motor with a power rating of 250 W.
I have calculated the predicted current vs speed and plot it against the practical.

also here is a torque against speed graph with predicted and practical measurements at 30 Hz

Can someone please explain the differences between predicted and practical measurements and why they happen.

Thanks

 

The answer seems obvious. The model you used to make your predictions, which is a mystery to us because you haven't shared it, is not a good model. Or, your data is poor. Or both.

 

here is the file I used to calculate the predicted calculations. Its an excel file but I cant upload here.

 

Also how can I estimate friction and windage torque from the given values

Rs=33.8
Rr=29.5
Xs= 26.8
Xr=26.8
Xm=702
Pf= 16.5

 

alright, it seemed I figured it out. can someone please explain the relationship between current and speed in an induction motor.
also how can I calculate the friction and windage loss in an induction motor.

Thanks

 

An induction motor attempts to run at synchronism, and RPM is dependent on slip and number of poles.
Increase in current usually accompanied by increase in slip frequency.
Slip= synchronous speed - actual rpm.
Max.

 

Thanks
How can i calculate friction and windage losses?