Study on stator groove and rotor pole combination of permanent magnet brushless DC motor

In recent years, with the development of power electronics technology and permanent magnet materials, permanent magnet brushless DC motor has developed rapidly and is widely used in electric vehicles, flywheel energy storage, rail transit and other fields. Its design level will directly affect these fields. In the process of motor design, it is very important to choose the appropriate combination of stator slot and rotor pole number. Different groove pole combination of permanent magnet brushless DC motor will directly affect the performance of the motor. Therefore, the influence of different ratio of stator slot and rotor pole on motor performance is analyzed by finite element method. By setting excitation source and boundary condition, the influence of different groove pole combination on magnetic density distribution, magnetic resistance moment, no-load back potential and no-load winding flux linkage of permanent magnet brushless DC motor is analyzed. The results showed, the lowest magnetic induction intensity is distributed in the rotating shaft, permanent magnet, stator winding and yoke of the motor. The flux waveform is sine wave, and the motor with 8 poles and 24 slots has the largest flux curve frequency and the smallest flux curve frequency, while the motor with 4 poles and 24 slots has the smallest flux curve frequency and the largest flux.