Indian Journal of Science and Technology

Abstract

This paper presents the optimized harmonic elimination stepped waveform technique to improve the output waveform of 7-level Cascaded Multilevel Inverter (CMLI) fed induction motor. The CMLI with separate DC source is used generate a 7-level output with three H-bridge and 12 switch’s. The working of 7-level CMLI is analyzed by phase disposition and phase shifting pulse width modulation with bipolar and unipolar modes of operation. The performance of CMLI is examined by various parameters such as THD, power factor, motor current, motor speed and torque. The presented result carried out using MATLAB/simulink. The simulation result for phase disposition and phase shift carrier PWM were compared. The 7-level CMLI hardware with phase shift carrier modulation was developed to validate simulation result
Keywords: CMLI, Phase Disposition, Phase Shift Carrier, Single Phase Asynchronous Induction Motor, THD, Unipolar and Bipolar