A novel 19L hybrid multilevel inverter system synthesizes reduced number of switches for hybrid renewable energy applications

Abstract

This paper presents a novel hybrid Multilevel Inverter (MLI) system. This hybrid system consisted of a nine-Level MLI unit that is connected back to back with a developed H-Bridge unit. The combination synthesizes only 10 power switches, two diodes, and four DC supplies to generate an output voltage waveform with 19 steps. The high number of steps in the output voltage helps produce a fine output waveform and more close to the sinusoidal shape with a small amount of THD. Also, it reduces the voltage stress across the switches and gives it a long lifetime, which brings more reliability. Moreover, the system synthesizes a reduced number of switches, which reduces the power losses and achieves high efficiency, and ensures small size and low cost for the proposed system. For amplifying the output power level, the paper presents two scenarios for the system expansion; both the scenarios achieve good results. To highlight the features of the proposed topology, a comparison between the proposed topology and the recently MLI topologies have been held. The comparison shows good advantages for the proposed topology over the other topologies. Two different controlling schemes (low switching frequency and model predictive control [MPC]) have been applied to control the proposed topology. The validation of the proposed topology was given through the simulation results based on MATLAB/Simulink for both the basic unit and the expanded system. Also, an experimental prototype based on the DSpace−1103 controller has been built, and the captured results support the simulation results.