Calculation of Starting Performance for Large Two Pole Induction Motors with Comparison to Test Values

Prediction of starting currents and torques in large two pole squirrel cage induction machines (SCIM) is a very complex problem. When values for these parameters are predicted using classical equivalent circuit formulations available in the literature, they do not always agree with test results. These discrepancies may result because of the difficulties associated with estimating the end parameters for the machine, namely the end leakage reactances and end ring resistance. This paper examines the effect of these end parameters on starting calculations made by means of equivalent circuit computations derived from finite element (FE) field solutions. The results indicate that the predictions are very sensitive to values used to estimate these end parameters