Optimization of a High Torque Density Small Hybrid Stepper using 3D FEM Model

Abstract

The paper presents an optimization of a small two-phase hybrid stepper with eight poles, 90 rotor teeth, and imposed outer geometry. The rotor permanent magnet dimensions, the tooth/slot width ratio, as well as the gap between the two rotor parts were modified to analyze their influence upon motor holding torque and detent torque. Solutions for obtaining a higher torque density or a smaller detent torque are proposed.