A Modified Multistage Converter Fed Multilevel Inverter with Reduced Inductor Current for Hybrid Power Systems

Abstract

The modern power electronics system has shifted toward the adoption of multilevel inverter configurations to achieve high-precision quality and high-quality voltage output. Nevertheless, traditional cascaded topologies have many challenges, such as large input current ripple, limited voltage level generation, and complex interfacing between direct current (DC)–DC boost stages and alternating current (AC) output stage. Such constraints impair the general operation and effectiveness of these systems. The proposed work introduces a modified multistage converter-fed cascaded multilevel inverter configuration aimed at enhancing the performance and efficiency of multilevel inverters for modern power applications. The presented topology includes three main stages: a multistage boost converter, level shifter and H-bridge. The enhanced multistage converter efficiently produces multiple voltage levels at the load while reducing the input inductor current. The level shifter circuit seamlessly connects the boost converter to the H-bridge and delivers a unidirectional multilevel voltage. The H-bridge converted the input into multilevel AC voltage. The design features a hybrid input setup with dual voltage sources, examining both single- and dual-input scenarios. Comprehensive simulation results are presented for both boost converter and inverter functions. A hardware prototype validated the simulation findings, demonstrating the practical viability of the proposed multistage converter-fed multilevel inverter in real-world applications.