• A. Annai Theresa
• Sinu Cleetus
• A. Abinesh
• C.Thamizharasan
• S. Shanmuganatham

Several industrial applications require high power inverter with sinusoidal waveforms with minimum distortion. For medium and high power applications, it is difficult to attain depending on a single switch. Therefore, the concept of multilevel inverters where introduced in 1974. At present situation, multilevel inverter is becoming more popular due to its staircase output whose characteristics is closer to the characteristics of sinusoidal waveform. But generally it has some disadvantages like, requirement of increased number of switches and complex pulse width modulation methods to reduce harmonics. The cascaded H-bridge multilevel inverter requires least number of components to achieve various voltage level by which the quality output is obtained. However as the number of voltage levels m grows, the number of active switches increases according to 2× (m-1) for the cascaded H Bridge. Here, the novel multilevel inverter topology with a reduced number of power switches is proposed and the switching frequency is getting reduced. The power quality of the proposed system is improved by using selective harmonic elimination (SHE) method. The whole system is numerically reformed developing MATLAB/SIMULINK and the simulation results are presented.

Multilevel inverter (MLIs), PWM techniques and Total Harmonic Distortion (THD), Cascaded H-bridge, SHE.

"21 LEVEL STAIRCASE SINE WAVE INVERTER WITH REDUCED SWITCHES AND THD", International Journal of Emerging Technologies and Innovative Research (www.jetir.org), ISSN:2349-5162, Vol.7, Issue 3, page no.318-323, March-2020, Available :http://www.jetir.org/papers/JETIR2003051.pdf

"21 LEVEL STAIRCASE SINE WAVE INVERTER WITH REDUCED SWITCHES AND THD", International Journal of Emerging Technologies and Innovative Research (www.jetir.org | UGC and issn Approved), ISSN:2349-5162, Vol.7, Issue 3, page no. pp318-323, March-2020, Available at : http://www.jetir.org/papers/JETIR2003051.pdf