Modeling and Analysis of Multilevel Inverter Topologies with Sustainable Energy

Abstract

Multilevel inverters (MLIs) have emerged as a foundational component in modern power electronics, particularly in medium- and high-voltage applications where conventional two-level inverters are no longer sufficient to meet performance, efficiency, and reliability standards. One of the primary motivations behind the widespread adoption of MLIs is their ability to synthesize high-quality output voltages with lower total harmonic distortion (THD), thereby improving power quality and system compatibility. This harmonic reduction is crucial in industrial and utility-scale applications, where precise voltage waveforms are essential for the reliable operation of motors, transformers, and sensitive loads. This paper introduces a novel multilevel inverter topology based on the cascaded connection of fundamental inverter modules. The proposed configuration is designed to operate efficiently in both symmetrical and asymmetrical modes, making it highly suitable for integration with renewable energy sources such as fuel cells and photovoltaic systems. In the symmetrical arrangement, each module utilizes identical DC source magnitudes, whereas in the asymmetrical configuration, unequal DC voltage levels—derived through binary or trinary progression—are employed to generate a greater number of output voltage levels using fewer components. The comparative analysis demonstrates that the proposed topology significantly reduces the number of power switches and passive components required, leading to lower power losses and enhanced overall inverter efficiency. Additionally, the total standing voltage stress on the semiconductor switches remains within acceptable limits, thereby improving reliability and operational safety compared to conventional multilevel inverter designs. The flexibility and simplicity of the proposed structure make it an ideal candidate for low- to medium-power renewable energy applications. To validate the functionality and effectiveness of the design, both simulation and experimental results are presented for 11-level, 15-level, and 19-level inverter configurations. The results confirm that the proposed inverter achieves high-quality output voltage waveforms with minimized harmonic distortion and improved performance across various load conditions.