A Study on the Effect of Induction Motor Design Parameters for Harmonic Losses

Induction motors are the most widely used industrial electric motors, and improving their efficiency is essential for achieving decarbonization targets. This study focuses on secondary copper losses in the rotor, with particular attention to their correlation with design parameters. While the ultimate goal is to contribute to high-efficiency motor design, the analysis is conducted not only from the perspective of efficiency but also from the viewpoint of output torque. Specifically, the torque contribution ratio, defined as the fraction of the fundamental component of the secondary copper losses to the total secondary copper losses, is introduced as an evaluation metric. To this end, the numerical analysis method used to evaluate the harmonic components of the secondary losses is presented. In the analysis, the number of rotor slots and the short-pitch ratio are treated as key parameters. Based on the results, generalizable insights for induction motor design are derived.