PWM SWITCHING STRATEGY FOR TORQUE RIPPLE MINIMIZATION IN BLDC MOTOR

Wael A. Salah – Dahaman Ishak – Khaleel J. Hammadi

   This paper describes a new PWM switching strategy to minimize the torque ripples in BLDC motor which is based on sensored rotor position control. The scheme has been implemented using a PIC microcontroller to generate a modified Pulse Width Modulation (PWM) signals for driving power inverter bridge. The modified PWM signals are successfully applied to the next up-coming phase current such that its current rise is slightly delayed during the commutation instant. Experimental results show that the current waveforms of the modified PWM are smoother than that in conventional PWM technique. Hence, the output torque exhibits lower ripple contents.

Keywords: permanent magnet, brushless DC, modified PWM, sensored control, torque ripple

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