Efficient Model Development for an Assembled Rotor of an Induction Motor Using a Condensed Modal Functional

Abstract

In order to predict the lateral rotordynamics of a high-speed induction motor, an optimization procedure is proposed for identifying the equivalent constitutive properties especially those of the magnetic core: an assembly of lamination stack, tie rods, and short-circuit rods. Modal parameters predicted by a finite element (FE) branched model based mainly on beam and disk elements and measured on an induction motor are included in an original energy functional. The minimization of this functional by using the Levenberg–Marquardt algorithm permits extracting the equivalent constitutive properties of the lamination stack.