Dual FEM-Simulink analysis of induction motor operating under unbalanced state

This paper presents a dual approach concerning the influence of unbalanced supply voltage on the three-phase induction motor operation. On one hand, a FEM-based analysis examines the ill effects upon the magnetic field, as main concern, and a few electric and mechanical parameters. On the other hand, a study of the transitory regime (including no-load startup and sudden loading) is employed under Simulink environment. To this aim, an original equation system, developed by the authors and called “in total fluxes” is used. The both analyses take into discussion a 3.5kW cage induction motor and two unbalanced degrees. Among other effects, the results put in view the huge influence of the voltage unbalances upon the torque and speed smoothness, which finally turns into vibrations and noise.