Design and Analysis of 21 level Symmetric Multilevel Inverter for Direct Grid Integration of Solar Photovoltaic systems

A novel 21 level symmetric multilevel inverter topology with symmetric DC sources which is suitable for PV applications is proposed in this paper. The suggested 21-level multilevel inverter's design was created using MATLAB/Simulink and the effectiveness of the suggested topology has been assessed using a variety of load combinations including dynamic load fluctuations. Besides, the existing 21 level MLI topologies are compared to the suggested topology in terms of the quantity of switches, DC sources, diodes, capacitors, and gate driver circuits. The proposed topology exhibits satisfactory performance based on the points of comparison such as total devices count devices power rating, minimum blocking voltage and efficiency. Compared to Traditional topologies like NPC, DC, and CHB MLI. The total harmonic distortion (THD) of the proposed topology is found 5.64% which is very close to IEEE standard.