Evaluative Study of Cascaded Multilevel Inverter Topologies

Multilevel inverters have recently gained popularity due to their ability to deliver virtually pure ac output voltage using different dc sources. Multilevel inverters have many special characteristics over two-level inverters such as high-performance efficiency, low unit ratings, structural modularity in their cascade topology, and so forth. One of the most rarely used topologies is the cascade topology in which the number of output voltage levels can be increased by connecting the identical module of the inverter in a series string. The conventional cascade topology has many cons that include the use of an increased number of switches and complexity in modulation schemes. Hence to overcome these problems a modified topology has been put forward in which for the same preferred output voltage the number of solid-state devices get reduced. In this research work, a comparative assessment has been realized to conclude the best among the two topologies.