Experimental Modal Analysis of Stators Analyzing the Effects of Lamination and Winding

Abstract

This paper addresses the experimental analysis of different stator configurations of an electric motor typically used within the automotive sector. The ongoing electrification of the automotive sector, combined with a desire to increase virtual prototyping, means that engineers are increasingly facing new challenges. Against this background, the numerical models of electric motors, particularly stators, are simplified and homogenized. However, this procedure must be supplemented by experimental data to ensure the high quality and reliability of the simulations. Unfortunately, broad experimental investigations are time-consuming and expensive, underlined by the lack of corresponding literature. For this reason, four different stator configurations were investigated as part of the experimental modal analysis to highlight the influence of the stator lamination as well as the winding. The results provide the scientific community with a broad outline of how specific influences change modal parameters of each stator configuration. In particular, the results show that lamination significantly reduces axial stiffness. Highlights of the findings relate to the mode-dependent stiffness, mass, and damping influences due to the winding, with the influence of the stiffness deviating significantly from expectation. It was also found that the selected winding technology dominates the structural dynamic system characteristics. Therefore, it is advisable to include the manufacturing technology intended to be used for the lamination and the winding in the early simulative design phase to improve the model prediction quality.