A 15-Level Inverter with Shifted-Level Variable Frequency Switching for Harmonic Reduction

The expansion of inverters to more than two layers with the goal of reducing distortion from the fundamental sinusoidal waveform gave rise to the concept of a multilayer inverter. One disadvantage of multiple level inverters is the need for more switches, increasing system bulk and cost while decreasing system reliability because of the extra components. The result distortion is lessened by the increase in inverter levels. In this study, a variety of switching approaches have been tried using a symmetrical 15 level inverter (15-LI) and their results are compared with 180 degree shifted adjacent level pulse span modulation. Effective switching techniques may also minimise distortion. The model and variable switching scheme are constructed using the MATLAB platform, and an analysis is performed to determine the utility of the result.