THE VIBRATIONAL ANALYSIS AND EXPERIMENTAL-VERIFICATION OF A PLANE ELECTRICAL MACHINE STATOR MODEL

The vibrational behaviour of the laminated stator of an electrical machine is quite different from that of a homogeneous solid cylinder, which is often used as a model for the purpose of predicting the natural frequencies. The purpose of this paper is to present a study of the effect of laminations on the vibrations of a stator. Based on both analytical results obtained for solid circular annular plates and experimental results of solid and laminated circular annular plates, it is found that the vibrational behaviour of an assembly of laminated circular annular plates, such as a stator, is dominated by that of an individual component of the assembly. The effect of laminations on the transverse vibrational modes is much greater than on the in-plane vibrational modes. As the clamping pressure or the number of the plates increases the transverse modes disappear gradually leaving the in-plane vibrations as the dominant vibrations. Hence, the plane model is a more efficient model than the solid cylinder model, because such a model excludes all of the other modes, predicted by the homogeneous cylinder theory, which are not found experimentally when an actual stator is tested. (C) 1995 Academic Press Limited