Novel configurations for cascaded multilevel inverter with hybrid and asymmetric architecture

PurposeThe power share from renewable energy sources (RES) in the existing grids is day by day increasing enormously. Multilevel inverter (MLI) is a sustained technology for integrating power from RES into the grid. Among various topologies of MLI, the Asymmetric Cascaded Multilevel Inverter (ACMLI) can produce a high-quality output by generating greater number of levels in the output voltage waveform. However, its designing depends on many power switches and therefore has increased power losses and higher cost. This also causes inventory issues at the user end. Therefore, to solve these issues, this paper aims to suggest a new ACMLI topology which can create a greater number of levels without increasing the hardware of a base level-doubling topology.Design/methodology/approachThe approach used in this study is hybridization of two types of switch modules. Suitable Algorithms are then applied to increase the output levels without increasing the hardware of a referenced level-doubling topology. This also ensures the requirement of minimum number of DC input sources and minimum variety of power-switch ratings. Mix Methodology has been used in this research which includes Quantitative, Qualitative and Experiment Method to ascertain the functionality and superiority of the proposed design.FindingsBased on a comprehensive evaluation of performance parameters and a comparative analysis, the study reveals that the proposed design exhibits superior features than many existing ACMLI designs. Architectural advantages have been fully exploited to minimize conduction power losses, resulting in increased efficiency. The proposed topology excels in reducing the hardware, minimizing cost and facilitating spares management. It can be a potential candidate for industrial applications based on the RES, especially the photovoltaic systems.Originality/valueThe proposed design extracts a sub-module of different characteristics by reorienting the switches of one stage of a sub-multilevel module. This enables generation of enhanced levels by a base topology restricted to produce twice number of levels in its original shape. The design is unique and has added value by virtue of improving the power quality, without requiring additional hardware.