Symmetrical Multilevel Cascaded H-Bridge Inverter Using Multicarrier SPWM Technique

An efficient multicarrier SPWM for cascaded H-Bridge symmetrical multilevel inverter is discussed here. The performance output levels of the CHB MLI is depends on number of DC input voltage sources. If two DC sources are applied then it gives five levels at output and three DC sources gives seven levels of output. In this papermulticarrierSPWM switching is provided to the multilevel inverter switches. In this switching method two signals are used, one is reference and another is carrier signal. For SPWM technique reference signal is sine wave and triangular wave is carrier signal. This type of inverters have thecapability to produce waveforms with better harmonic spectrum and realistic output results. The results of the model shows that the THD is reduced with the modulation of sinusoidal pulse width. The simulation results shows that quality of output voltagewaveform gets improved with less loss as well as lower THD.