How do I compute end ring resistance and inductance for an induction machine?

Yann_Le_Floch

The principle is to represent the ring as an axisymmetrical problem. The ring is supplied by a voltage. The resistance and inductance can be extracted from the power and the current:

R = P / (I*I) / Nb and L = Q / (I*I) / omega / Nb

With:

• R : resistance of end ring
• P : power in the ring
• I : current in the bar (in rms value)
• Nb : number of bars
• Q : sum of reactive power in the whole domain (air plus bar)
• Omega : pulsation of supply

With this method, the frequency can be parameterized from 50 Hz to 1 kHz for instance, in order to see the impact on the values.

You can ask the support team to send you a technical sheet “Computation of end ring resistance and inductance”.