Parameter refinement in optimization of PMDC motor using orthogonal arrays

The performance of permanent magnet DC motor was improved by multi-objective optimization of its magnetic circuit. That can be achieved by means of finite element method in torque calculation and statistical analysis using orthogonal arrays constructed for one (or more) parameter level refinement at very reduced number of field calculations. The magnetic field was calculated taking into account non-linear density and effect of current commutation. The electromagnetic torque was obtained from magnetic vector potentials of moving conductors. The effect of change for every geometric parameter was particularly calculated. A fast improvement in shapes of the motor magnetic parts was achieved by an appropriate number of field and torque calculations.