Review on Torque Ripple Reduction Techniques of BLDC Motor

Abstract

This paper reviews the torque ripple reduction techniques of Brushless DC motor (BLDC). Torque ripple arises in BLDC motor due to the attraction of rotor's permanent magnets and stator's ferro magnet teeth. The magnetic attraction varies depending on the strength of the magnetic field and this dissimilarity leads to the production of irregular torque called torque ripples. This torque ripple may cause poor quality of speed-torque characteristics, noise, vibrations and produce stern faults in sensor less motor drives. This paper analyses various techniques for the reduction of torque ripples. The analysis shows that the torque ripple in the BLDC motor can be minimized during commutation time by increasing the input voltage four times greater than the back emf. Also, this paper reviews different methodologies to boost the input voltages during the commutation period.