Modeling and analysis of radial electromagnetic force and vibroacoustic behaviour in switched reluctance motors

Abstract

In this paper, the radial electromagnetic force and vibroacoustic behaviour of a switched reluctance motor (SRM) are predicted and analysed in detail. First, the radial force with the spatial–temporal distribution characteristics is derived analytically and verified by the 2D Fourier transform. Second, a multiphysics model, which not only includes the electromagnetic field, the mechanical field, and the acoustic field, but also takes into account the structural orthotropy and the non-uniformly distributed electromagnetic force, is established to predict the electromagnetic vibration and noise of a SRM. Third, based on the spatial and temporal orders of the force harmonics, the vibroacoustic mechanism of a SRM is revealed. Finally, the electromagnetic force and vibration under two control strategies, which include the angle position control (APC) and the current chopping control (CCC), are compared and analysed, respectively. The results show that the electromagnetic vibration and noise of a three-phase 12/8 SRM are mainly caused by the force harmonics with the spatial order of 4 and the temporal orders of 3 N0 ± 1 (N0 = 0, 1, 2···). Besides, under the two control strategies, the orders of the electromagnetic force and vibration are the same, but the amplitudes are different.