Learning Forum

[shahsyed]

I am working on a three-phase four-pole induction machine, and my target is to do a parameteric transient analysis. 

Using RPM as a parameter and changing the supply frequency accordingly. The conversion formula is freq = (RPM*Poles)/120. If the unit of RPM is rpm, the value of the expression is 40.545rpm (rather than some value in Hz). If the unitless RPM is used, the value is 387.17623rpm. My question is, "Is there any special way to write down this expression so that I can get a proper frequency value?"

Thank you for your time.

[Aravind Babu]

Hi,

The expression for Frequency = MachineRPM / 1rpm * NumPoles / 120 / (1 - slip).

Considering MachineRPM is defined with Unit: rpm.