Optimal core shape design for cogging torque reduction of brushless DC motor using genetic algorithm

The cogging torque in the small brushless DC (BLDC) motors used in the digital versatile disk (DVD) driving system or hard disk drive (HDD) system can cause some serious vibration problems. In this paper, some core shapes that reduce cogging torque are found by using the reluctance network method (RNM) for magnetic field analysis and genetic algorithms (GAs) for optimization. The outer rotor type BLDC motor for the DVD ROM driving system is optimized as a sample model.