Simulation of Novel ۱۵-Level Cascaded Inverters Using Proposed RSPWM Technique for Connecting to the Grid

Inverter is one of the most important parts in a grid-connected single-phase photovoltaic system. In this paper, two new cascaded inverters which are used for the grid-connected systems have been introduced and simulated. These proposed inverters are two new inverters, which each one has two cascaded full-bridges inverter. These structures, because of the different input voltage in each of the full-bridges, are called asymmetric cascaded inverters. In these Inverters, the changes have been created in one of the full-bridges that lead to the difference between two full-bridges from each other. Changing in one of the full-bridges and the feature of the asymmetry are leading to increase the number of voltage levels at the inverter output. Also, for controlling the proposed Inverters, reverse sinusoidal pulse width modulation (RSPWM) technique is used. Finally, in these two proposed topologies, the quality of output voltage waveform is improved, and voltage harmonics and total harmonic distortion (THD) are reduced. In this article, some features of these two new converters and comparison of them with each other are given. PSCAD software is used for simulation of these converters