Finite-element models for cage induction motor analysis

The authors describe two methods for predicting the performance of cage induction motors using finite elements. The first, which is suitable for steady-state analysis, uses a phaseband model for the stator together with a single-slot model for the rotor. These are used in an iterative procedure to determine the components of the familiar per-phase equivalent circuit. The second method, which is suitable for transient analysis, uses a time-stepped coupled circuit model for the machine, together with magnetostatic finite-element field solutions which are used to update the circuit parameters. Both methods are illustrated by comparison between experimental and computed characteristics for a four-pole 4.5 kW motor.<>