Author : S. Naresh and Rosaiah Mudigonla

One of the major problems in electric power is power quality while converting form DC to AC is the harmonic contents. Multilevel inverters produce a staircase output voltage from DC voltage sources. Requiring great number of semiconductor switches and this is main disadvantage of the multilevel inverters. Application of multilevel inverter for high power equipments in industry has become popular because of its high-quality output waveform. In this paper, a three phase seventeen level single switch cascaded multilevel inverter is proposed with reduced number of switches, harmonic content and losses. An algorithm has been generated on the basis of optimized harmonic stepped wave form technique (OHSWT) to find out firing angle for multilevel inverter with unequal DC sauces to reduce harmonic content present in output. The main attention behind the objective of proposed project seventeen level Single Switch Cascade multilevel inverter topology is to achieve the high power quality, low total harmonic distortion and better power factor. The harmonic content can be measured in terms of total harmonic distortion by using FFT analysis harmonic spectrum. The proposed multilevel inverter has been validated using MATLAB/SIMULINK software.

Keywords: Total harmonic distortion(THD), Optimized harmonic stepped waveform (OHSW), Cascaded H-bridge inverter(CHI), Voltage-source inverter(VSI), Multilevel inverters, Single Switch Cascade multilevel inverter(SSCMI), Fast Fourier analysis(FFT), insulated gate bipolar transistor(IGBT)

Article published in International Journal of Current Engineering and Technology, Vol.5, No.4 (Aug-2015)