The Effect of Structural Material Parameters on the Operational Characteristic of Traction Drives for EV Applications

In this article, the effect of structural material parameters of nongrain-oriented (NO) electrical steel on the driving cycle losses and torque-speed characteristics of electrical traction drives for electric vehicle (EV) applications is studied. The operating point distribution in different driving cycles affects the iron losses and magnetization behavior. As a result, the ideal material choice not only depends on the machine design and topology but also on the application requirements. Structural material parameters of electrical steel, that is, alloying, sheet thickness, grain size, and crystallographic texture, are measures to modulate the magnetic properties. Their effect on iron-loss components is studied for seven industrial NO electrical steel grades. Two traction drives and four driving cycles are evaluated with respect to the structural material parameters as application examples.