THE OPTIMAL LAMINATION APPROACH TO INDUCTION MACHINE-DESIGN GLOBAL OPTIMIZATION

Induction motor (IM) design represents a complex multivariable optimiz ation mathematical problem with constraints. Even recent advanced math ematical tools do not guarantee a global optimum. Based on a nonlinear analytical field-circuit model, this paper introduces a novel practic al approach structured in two stages, the optimal lamination and the l ongitudinal optimization. The first stage, divided into three substage s, produces a unique optimal lamination cross section for a given exte rnal stator diameter and number of poles, based on the criterion of ma ximum airgap flux density for given airgap and magnetization MMF. With only the external diameter and current density as independent variabl es, in the second stage, the chosen optimization objective function is minimized (maximized) in a straightforward iterative manner. Numerous practical examples have produced a global optimum.