Tangential effects on magnetic vibrations and acoustic noise of induction machines using subdomain method and electromagnetic vibration synthesis

In the vibroacoustic analysis of electrical machines, the effect of the tangential magnetic force on the vibrations is generally neglected compared with the radial magnetic force, as well as the effect of the tangential flux density on the radial force, especially for induction machines. In this paper, these two assumptions are studied for the case of an induction machine at no-load and load states. First, time and space distribution of the magnetic flux density - including radial and tangential components - is computed in the air gap using a new semi-analytical subdomain modeling technique of squirrel-cage induction machine, including all harmonics. Then, magnetic forces are obtained by applying the Maxwell stress tensor. Stator vibrations are finally computed with and without neglecting the tangential effects using electromagnetic vibration synthesis implemented in MANATEE software. Results show that both tangential effects have a small impact on the maximum emitted noise in the case of the studied induction machine.