Nearest Level Control for a Low-Component Single-Phase Asymmetrical Multilevel Inverter with Minimal Harmonic Distortion

Abstract Multilevel inverters (MLIs) play a crucial role in both industrial and academic fields due to their ability to achieve high voltage levels with minimal harmonic distortion, reduced power losses, and improved cost efficiency. Traditional designs, such as the cascaded H-bridge (CHB) topology, require a significant number of components, leading to increased complexity, higher costs, and decreased reliability. To overcome these challenges, this paper presents an advanced asymmetrical MLI topology with a reduced component count (RCC). The design is adaptable for three-phase systems and supports both modular and cascaded configurations, making it well-suited for high-voltage applications. By eliminating the need for an H-bridge to generate negative polarity, the topology minimizes the number of active switches in the conduction path to just three, thereby reducing power losses and voltage stress on the components. Nearest Level Control (NLC) is utilized as the switching strategy to enhance the converter’s performance. A comprehensive comparison with a conventional 15-level CHB MLI highlights the superior efficiency of the topology, demonstrating lower power losses and improved operational effectiveness. Furthermore, the design ensures enhanced scalability for higher voltage levels while maintaining system reliability