Dynamic load of induction machine due to rotor's eccentricity and bearing clearance

The most critical part of the induction machines which determines on their life time operation are rolling element bearings. To ensure reliable drive with an induction machine requires deep insight in electro-mechanical dynamics during its operation. The flexible multibody modeling technique enables the simulation of dynamic loads on all drive components. This paper focuses on complex dynamic modeling of machine's behavior in case of eccentrically placed rotor supported by nonlinear bearing with radial clearance. The life time of machine's bearing becomes very important issue of machine's maintenance and reliability and is markedly influenced by any unbalanced forces acting on the rotor. Only the complex electro-mechanical models of the rotor considering all unbalanced electrical and mechanical rotor forces can provide the very detailed information about the bearing load. The methodology of determination of such loading is applied to the 11 kW squirrel-cage induction machine.