Electromagnetic modelling of a rolling rotor actuator

An analytical technique is developed for the prediction of the instantaneous magnetic field distribution in the asymmetric airgap of a rolling-rotor actuator having an interior stator. It combines a lumped magnetic circuit model with an analysis which is based on MMF/permeance. The developed model accounts for the effect of both rotor eccentricity and stator slotting and was applied to the calculation of the winding inductances. Analytical calculations are shown to be in good agreement with finite element predictions.<>