The multilevel inverter systems may be unipolar switched
or bipolar switched [9]. Unipolar switched inverters have the
advantage of higher efficiency due to reduced switching loss
[10], and low iron loss of inductor in output filter [11].
Moreover, it generates less EM! [12], but it has been shown
theoretically [13] that distortion of their output current can be
significant, especially at low power levels. On the other hand
at the same current levels bipolar switched inverters results in
reduced low frequency harmonics, especially when power
output is low [9, 11]. In the paper, MA TLAB simulation
model is used for the analysis of the conventional PWM
inverter and the cascaded multilevel (seven) PWM inverter
using unipolar and bipolar switching schemes. The cascaded
multilevel inverter uses series strings of single phase full
bridge inverter to construct multilevel phase legs. A particular
advantage of this topology is that the modulation, control and
protection requirement of each bridge are modular