An Improved Phase Disposition SPWM Strategy for Cascaded Multilevel Inverter

<table class="table-group" width="800px"><tr class="fig-image" id="a"><td><img alt="731574.fig.009a" src="https://static.hindawi.com/articles/mpe/volume-2014/731574/figures/731574.fig.009a.jpg"/></td></tr><tr class="fig-caption"><td align="center"><table><tr><td><b>(a) </b>Major harmonic spectrum</td></tr></table></td></tr><tr class="fig-image" id="b"><td><img alt="731574.fig.009b" src="https://static.hindawi.com/articles/mpe/volume-2014/731574/figures/731574.fig.009b.jpg"/></td></tr><tr class="fig-caption"><td align="center"><table><tr><td><b>(b) </b>Harmonic spectrum around 4 times of the switching frequency</td></tr></table></td></tr></table>

<table>Spectrum analysis result of output phase voltage and line voltage.</table>

Mathematical Problems in Engineering

fig9

Figure 9

Figure 9: An Improved Phase Disposition SPWM Strategy for Cascaded Multilevel Inverter 