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Item Design and implementation of seven-level inverter for grid-tied photovoltaic systems(Taylor and Francis Ltd., 2025) Maheswari, G.; Manjunatha Sharma, K.M.; P, P.Multi-level inverters without transformer coupling are growingly popular for solar uses because of their compact design, minimised voltage stress, and improved efficiency. In this paper, the proposed novel triple-boost 7-level inverter is optimised for seamless integration with the grid. The proposed inverter employs self-regulating switched-capacitors to achieve a threefold voltage amplification, effectively eliminating the need for an independent boost converter stage. This architecture benefits low-voltage PV systems by improving efficiency, reducing cost, and ensuring superior performance. Moreover, the 7-level inverter adopts a common-ground topology, effectively mitigating leakage currents in PV system applications. The paper elaborates on the operational modes of the proposed inverter and the design of a current controller tailored for a grid-tied PV-based seven-level inverter. Additionally, simulation and experimental validation are conducted utilising hardware-in-the-loop (HIL) methods to evaluate system performance. Finally, a comprehensive comparative analysis is presented between the proposed seven-level inverter and existing seven-level inverters, highlighting the advantages of the proposed inverter design. © 2025 Informa UK Limited, trading as Taylor & Francis Group.Item Implementation of a Novel Quadruple-Boost Nine-Level Inverter for Grid-Tied Applications(Springer Nature, 2025) Maheswari, G.; Manjunatha Sharma, K.M.; Prabhakaran, P.This paper proposes a novel transformer-less quadruple-boost nine-level (QBNL) inverter specifically developed for grid-tied applications. Traditional multilevel inverters (MLIs) typically require numerous components and a transformer for grid integration, which increases cost, weight, size, and losses, thereby diminishing overall efficiency. The proposed nine-level quadruple-boost inverter overcomes these challenges by providing a more streamlined design, significantly enhancing system performance and efficiency. The topology of the proposed inverter consists of ten switches, one diode, and three switched capacitors. These capacitors are self-balanced, maintaining voltage levels at Vdc, 2Vdc, and 2Vdc relative to the input voltage. With a reduced component count (10), lower total standing voltage per unit (5.75), lower cost factor, improved efficiency (97.73), and higher power density, this design offers significant advantages over existing nine-level inverters. The proposed inverter has a soft charging circuit at the DC side to reduce the impulse currents, and a common-mode choke is inserted between the inverter output and the grid to reduce leakage current in PV applications. Additionally, the proposed system incorporates a proportional-integral (PI) controller and phase disposition pulse width modulation technique. A comparative analysis between the proposed nine-level quadruple-boost inverter and existing nine-level inverters highlights its superior performance. The effectiveness of the proposed quadruple-boost nine-level inverter is verified through MATLAB Simulink simulations and Experimental Hardware-in-the-Loop (EHIL) testing, confirming its suitability for grid-tied applications. © 2017 Elsevier Inc. All rights reserved. © The Author(s), under exclusive licence to Shiraz University 2025.Item A Novel Two Five-Level Double-Boost Inverters for Grid-Tied Photovoltaic Applications(Springer, 2025) Maheswari, G.; Manjunatha Sharma, K.M.; P, P.This paper proposes two novel five-level inverters, both featuring a common ground configuration and double-boosting capability. The common ground configuration in the proposed topologies effectively eliminates leakage current, making them ideal for grid-connected photovoltaic applications. The first proposed inverter topology consists of a single DC source, six power switches, two diodes, two capacitors, and one charging inductor. The second topology also uses a single DC source but comprises seven power switches, one diode, two capacitors, and one charging inductor. In both proposed inverter topologies, the switched capacitors automatically balance to voltages of Vdc and 2Vdc. Additionally, the charging inductor helps reduce spike currents in the capacitor charging path. These inverters offer several advantages, including a reduced component count, low per-unit total standing voltage, high efficiency, increased power density due to fewer components, reduced spike currents, and a common ground (CG) structure that entirely eliminates leakage current. The proposed inverters employ a proportional-integral (PI) controller with phase disposition pulse-width modulation (for the first converter) and staircase modulation (for the second converter). A comparative analysis of existing and proposed five-level inverters is presented, demonstrating their suitability for grid-tied photovoltaic applications through MATLAB Simulink simulations and experimental validation using Hardware-in-the-Loop (HIL). © The Author(s), under exclusive licence to Springer Nature Singapore Pte Ltd. 2025.