Influence of electromagnetic field damping on forced vibrations of induction rotors caused by dynamic rotor eccentricity
- The paper shows an analytical rotordynamic model for induction rotors, supported in sleeve bearings, especially focusing on the influence of electromagnetic field damping on the forced rotor vibrations. The analytical model contains electromagnetic forces in respect of electromagnetic field damping, stiffness and internal material damping of the rotor, typical dynamic eccentricities of an induction rotor – mass eccentricity, bent rotor deflection and magnetic eccentricity –, stiffness and damping of the support, and stiffness and damping of the oil film of the sleeve bearings. With this rotordynamic model a useful possibility is shown, how to consider electromagnetic field damping, when analyzing forced vibrations caused by dynamic eccentricities. The aim of the paper is to show a method – based on a simple rotor dynamic model – how to consider electromagnetic field damping, which can also be adopted in Finite-Element-Analysis.