Analysis of the starting process of a disk drive spindle motor by time stepping finite element method

An analysis of the starting process of the disk drive spindle motor using the time stepping finite element method (FEM) is presented. The electromagnetic field is coupled with the stator circuit and motion equations and solved simultaneously at each time step. The model also includes control elements. By coupling the control loop features with the time stepping FEM model, the stator winding can be fed with the actual output voltages from the inverter, as in an actual system. The saturation effects, the eddy current effects, the harmonic effects, and the control nonlinearities are all taken into account in the system of equations. Torque, speed, and current with different set limits in the starting regime are investigated in this paper.