Dynamic analysis of axial magnetic forces for DVD spindle motors

The axial magnetic force, induced by the complicated flux linkage distribut ion from rotor magnet and stator slotted, is constructed by different relat ive heights and calculated by 3D finite element method (FEM) to analyze the dynamic characteristics for a DVD spindle motor. The axial magnetic force is designed to provide an axial stiffness and govern the natural frequency of the dynamic performance. According to the simulation results and experim ental measurements, the dynamic behaviors are significantly improved with a variation of relative height of rotor magnet and stator slotted on a DVD s pindle motor.