Stator pole arrangement of the permanent magnet stepper motor with asymmetric stator for achieving the uniform step

A special type of a two-phase permanent magnet stepper motor with asymmetric stator was constructed for the specific purpose. The structural design was based on a modified geometry of standard stator and a functional motor prototype was built. The measurement of the step uniformity reveals irregular step size for half-stepping driver. This paper presents the approach to find proper stator pole dimensions to achieve uniform step in half-stepping regime of permanent magnet stepper motor. The simulation of a magnetic circuit was used. The measurement on the prototype and the simulation of the motor angle for different stator arrangement are presented.