| Actually, the permanent magnet brushless DC motor (BLDCM) belongs to the family of permanent magnet synchronous motor. With its trapezoidal back-EMF waveform and rectangle current waveform, BLDCM combines the advantages of permanent magnet synchronous motor and DC motor together. BLDCM has been popular with various sectors in national economy because of its'low cost, achievable control method, short development period and high reliability. However, torque ripple problem due to the special structure and control method for BLDCM would seriously hamper further improvement of its performance in position and speed control, which make it unable to satisfy the requirements of some high-precision fields. Therefore, this paper carried out the research work in torque ripple suppression about the torque ripple in BLDCM.First of all, mathematical model was built based on the principle of BLDCM, and further constructed BLDCM control system using Simulink/PLECS, proving the feasibility of simulation model, point out the torque ripple existing. Secondly, this paper analyzed the characteristics of torque, causes of torque ripple, and influencing factors with torque in BLDCM. Particularity, Influences of back-EMF and current in commutation on torque ripple was emphatically analyzed. This paper also discussed main mechanism of torque ripple in commutation. To suppress torque ripple, the commutation current control method was proposed on the basis of commutation angle integral method. Compared with commutation angle integral method, this new method can inhibit torque ripple more effectively. Finally, BLDCM control system experiment platform was developed based on DSPACE real-time simulation platform. After brought commutation current control method into this control system, simulation results proved the validity of this method. The study in this paper has a positive theoretical meaning and application value for further enhancing control performance and expanding scope of application of brushless DC motor.
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