The robust design approach for reducing cogging torque in permanent magnet motors for CD-ROM spindles

This paper discusses the robust design method for reducing the cogging torque developed in permanent magnet motors and improving the N/S ratio (noise to signal ratio) between the cogging torque and average operational torque. The robust design method used is Taguchi's approach which is applied the first time to determine the optimum design parameters of a brushless DC spindle motor used in data storage systems. The results show that the robust design method is a very efficient and effective approach in designing disk drive spindle motors for high performance.