Calculation of eccentricity harmonics of the air-gap flux density in induction Machines by impulse method

The rotor eccentricity creates extra harmonics into the flux-density distribution in the air gap. Together with the fundamental field-component, these harmonics create the total force acting between the stator and eccentric rotor. The paper presents a new application of the impulse method, which enables the calculation of the harmonics of the flux density distribution when the rotor is eccentric. The idea of the application is to move the center point of the rotor from its central position for a short period of time during transient finite-element calculation. The flux-density harmonics are then calculated from the response and excitation signals.