Symmetric and Asymmetric Multilevel Inverter Topologies With Reduced Device Count

Abstract

In this work, two new topologies of single-phase hybrid multilevel inverters for symmetrical and asymmetrical configurations are presented for use in drives and control of electrical machines and the connection of renewable energy sources. The proposed topology uses 2 dc sources, 12 switches, 1 flying capacitor, and 3 diodes to generate boosted 13-levels and 17-levels for symmetric and asymmetric configuration, respectively. Self-voltage balancing of its capacitor voltage regardless of load type, load dynamics, or modulation index is a key advantage of the suggested design. The higher performance of proposed topologies in terms of the total number of switches, TSV, THD, switch stress, and dc sources are demonstrated by comparing those with recently published topologies. In addition, a widely employed nearest level control modulation approach is used to provide output voltage levels with low THD. Finally, experiments were undertaken to validate the performance of the suggested topology.INDEX TERMS Multilevel inverter (MLI), switched-capacitor, nearest level control (NLC), total standing voltage (TSV). MOHAMMED A. AL-HITMI (Member, IEEE) received the B.Sc. degree in electrical engineering from Qatar University, Doha, Qatar, in 1992, and the M.S. and Ph.D. degrees in control engineering from The University of Sheffield, in 1994 and 2002, respectively. He is currently an Associate Professor of electrical engineering with Qatar University, where he is also working as the Head of the Department of Electrical Engineering. He has conducted many research projects funded by national and industrial funding agencies. He has authored more than 50 research papers in top peer-reviewed journals and conferences. His research interests include control systems theory, neural networks, fuzzy control, and electric drive systems. He is involved in several administrative committees in leadership roles with Qatar University. He is also serving as a reviewer for many top journals. MD. REYAZ HUSSAN (Student Member, IEEE) received the B.Tech. and M.Tech. degrees in electrical engineering and instrumentation and control

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Switched Capacitor Inverter with Reduced Inrush Current and High Boosting Gain

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Comparative Detailed Analysis of a 7-Level Cascaded H-Bridge Inverter in Symmetric and Asymmetric Configurations

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