Optimized Design of High-Speed Induction Motors in Respect of the Electrical Steel Grade

This paper presents the design of highly efficient high-speed induction motors with optimally exploited magnetic materials. First, new combined numerical-analytical design methods are presented and validated, which closely relate to the classical way of machine design but allow the designer to precisely account for material properties. Second, it is shown how two optimized 20-kW 30 000-r/min induction machines have been realized, i.e., one incorporating cobalt-iron alloy, and the other one using siliconized steel. Finally, the influence of the electrical steel grade on their performance is evaluated on the basis of electrical, thermal, vibrational, and noise measurements.