Equivalent orthotropic material parameters identification of electrical machines for modal analysis utilizing a PSO-assisted theoretical approach.

Accurate equivalent orthotropic material parameters (OMPs) of the stator core and windings are crucial for calculating the natural frequencies of the electrical machines (EMs), which is essential for the vibration and noise prediction. To perform a precise modal analysis of the EMs, an analytical method (AM) is proposed to identify equivalent OMPs of the stator core and windings for electrical machines in this study. Firstly, the AM for modal analysis of the stator core and assembly is derived using the first-order shear deformation theory. Furthermore, an identification method for the equivalent OMPs is proposed by employing the particle swarm optimization algorithm. Then, the method is implemented on an EM for the OMP identification, and the results demonstrate that the method not only achieves high accuracy but also requires less computation time. Finally, utilizing the identified OMPs, the modal frequencies of the entire EM are computed with a theoretical model, which is verified through finite element simulations and modal tests. The virtual springs technology is used to consider the actual boundaries, and the influence of different boundary conditions on the modal frequencies of the EM are compared. This study significantly contributes to the efficient and precise identification of OMPs in EMs, as well as facilitating rapid computation of modal frequencies. It also holds a pivotal position in the vibration and noise prediction of the EMs. [ABSTRACT FROM AUTHOR]