Laboratory for Dynamics of Machines and Structures 
Numerical Modeling of the Rotor Movement in a Permanent-Magnet Stepper Motor
 J. Škofic and M. Boltežar
IET Electric Power Applications, Volume 8, Issue 4, 2014, Pages 155 – 163

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This manuscript deals with predicting the dynamic behavior of the rotor in a claw-poled, permanent-magnet (PM), stepper motor. The FEM model of a prototype stepper is used to calculate the magnetic forces on the rotor, where the PM is modeled with an altered geometry approach. This altered geometry helps achieving a realistic magnetic flux density profile and direct PM material property input. The obtained forces are used in the following analysis as the excitation, to simulate the rotor’s rotational and also axial movements with the help of proposed system of equations. To validate the introduced modeling approach, a measurement of the rotational and axial movement was performed on a motor with the same geometry and material properties. The results of the simulated movement are in good agreement with the experimental data for the tested motor.


Jan Škofic, PhD

  Iskra Mehanizmi.


Miha Boltežar, PhD

  Ladisk, Faculty of Mechanical Engineering, University of Ljubljana
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