Variation of THD in output quantities of three pahse spwm-vsi by varying the parameters of RLC filter connected at output of inverter

Abstract

Paper deals with the analysis of three phase Sinusoidal pulse width modulated (SPWM) Voltage source inverter output in term of total harmonic distortion (THD). Analysis is done by implementing the model in MATLAB/SIMULINK platform. By implementing filter at the output terminals of inverter, its current and voltage wave becomes purely sinusoidal. Analysis is carried out by varying RLC filter parameters and due to their variation, effect on THD in inverter filtered line voltage, line current & phase voltage is measured. Filter inductance ‘L’ & capacitance ‘C’ are varied one by one keeping other parameters constant & effects has been plotted on various graphs & listed in tables. It has been observed that by varying the RLC filter parameters THD in output quantities of SPWM VSI inverter shows a remarkable change in its value. This work may provide one of the best alternative solutions to design a filter for SPWM VSI inverter feeding to any drive.