Analysis and Integration of Nine Level Cascaded H-Bridge Multilevel Inverter Configuration in a Photovoltaic System

Power electronics converters are gaining importance due to the reliable performance of grid-connected solar system or standalone solar system. In this paper nine levels cascaded H-bridge Multi-level inverter (CHB-MLI) is analyzed. The effectiveness of this multilevel inverter is investigated by replacing the input dc source in cascaded inverter bridge with separate PV array and boost converters. This PV fed nine levels CHB is analyzed in two ways: (i) with equal magnitude of input voltage source to inverter and (ii) with unequal magnitude of input voltage source. Total harmonic distortion (THD) analysis for both cases has been carried out. Different multicarrier PWM strategies are also discussed. Further, the improvement in power quality by using passive filters at the output end of MLI is shown. Results are verified in MATLAB/SIMULINK environment by performing simulation.