Loss reduction due to blanking parameter optimization for different non-grain oriented electrical steel grades

摘要

An optimized electrical machine design can improve its efficiency and power density. While magnetic and mechanical design of rotor and stator laminations for varying types of electrical machines is well understood, influence of process induced mechanical stresses on magnetic behavior of non-oriented electrical steel grades is widely unknown. Especially when looking at the blanking process, magnetic properties like iron losses and magnetizability are detrimentally altered due to cutting induced residual stresses. There have been investigations of individual electrical steel grades, which show a significant extent of magnetic property deterioration depending on the process parameters used. This paper studies influences of different blanking process parameters on magnetic properties of various non-oriented electrical steel grades. Several materials with different grain size, silicon content and thickness are investigated. Magnetic properties of processed electrical steel specimens are analyzed using a single sheet tester. The results enable a correlation between material grade, sheet thickness, blanking parameters and magnetic properties to be studied.