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Item Novel sorted PWM strategy and control for photovoltaic-based grid-connected cascaded H-bridge inverters(Springer, 2025) Maheswari, G.; Manjunatha Sharma, K.M.; Prabhakaran, P.This paper proposes a novel sorted level-shifted U-shaped carrier-based pulse width modulation (SLSUC PWM) strategy combined with an input power control approach for a 13-level cascaded H-bridge multi-level inverter designed for grid connection, specifically tailored for photovoltaic (PV) systems, which avoids a double-stage power conversion configuration. In this methodology, every inverter generates a quasi-square output voltage waveform with a width that is intricately linked to the output power of its corresponding PV panel. The application of this SLSUC pulse width modulation technique with input power control in a solar energy-based 13-level grid-tied inverter facilitates precise maximum power point (MPP) tracking for each of the PV panels under uniform and non-uniform irradiation conditions and ensures the consistent maintenance of capacitor voltage balance. Moreover, this novel SLSUC PWM method for 13-level inverters offers a range of benefits, including a low total harmonic distortion (THD) in the output voltage of the multi-level inverter and higher inverter and MPPT efficiencies over the existing PWM techniques. To verify the efficacy of the proposed control method over existing techniques, a PV-based grid-connected multi-level inverter with the proposed control strategy undergoes modeling and simulation using MATLAB/Simulink. Then, experimental hardware-in-the-loop (EHIL) testing is conducted to confirm and evaluate its effectiveness. © The Author(s) under exclusive licence to The Korean Institute of Power Electronics 2024.Item A Novel Seven-Level Triple-Boost Inverter for Grid-Integrated Photovoltaic Systems(Springer, 2025) Maheswari, G.; Manjunatha Sharma, K.M.; P, P.Transformer-less switched-capacitor-based multilevel inverters (TL-SCMLIs) are increasingly preferred for photovoltaic (PV) applications due to their voltage boosting capability, high efficiency, reduced dv/dt stress, and lower cost. However, existing SC-based multi-level inverters often require more components, suffer from leakage currents, have lower boost gain capability, have higher PU total standing voltage, and exhibit lower efficiency. To address these challenges, this paper proposes a novel seven-level switched-capacitor (SC)-based TL-MLI with higher voltage boosting gain and a common ground (CG) configuration for improved performance in grid-tied PV applications. A proportional-integral (PI) controller is designed for the grid-tied seven-level PV inverter, and its performance is evaluated through simulation studies and hardware-in-the-loop (HIL) experimental verification. Finally, a detailed comparative analysis with existing multi-level inverters highlights the proposed seven-level inverter’s advantages, including leakage current reduction, high boost gain, lower cost, lower PU total standing voltage, lower voltage stress, lower peak inverse voltage, and improved efficiency. The total harmonic distortion (THD) of the grid current is less than 5% for the proposed grid-tied seven-level inverter. © The Author(s), under exclusive licence to Springer Nature Singapore Pte Ltd. 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.