Harmonics and Torque Ripple Reduction in BLDC Drive using Multilevel Inverter

Abstract

Considering the drive advantages of BLDC drive compared to other drive applications BLDC with phase switching inverter performance is improved with multilevel inverter(MLI)topologies employing current and speed control techniques which decrease the torque ripples and harmonic distortion in general three phase three level inverter which commutates the BLDCM and address the problems of harmonics and torque ripples for that by using a multilevel inverter topology of five level inverter with current and speed controller at lower switching levels which can improves the BLDC drive performance. This paper proposes a series connected five level inverter with phase shift modulation with current and speed control techniques to reduce the harmonic distortion and torque ripples. The simulation results are discussed with a comparative study in different operating strategies of BLDC drive. Finally seven level Cascaded multilevel inverter with PWM fed Brushless dc motor drive is implemented in Matlab / Simulink and simulation results are presented for verification and validation of the proposed work.