Design and Performance Evaluation of Multilevel Inverter for Solar Energy Systems and Electric Vehicle Charging with Multi Output Active Clamp Forward Converter

This paper introduces a Multi-Output Active Clamp Forward Converter (MOACFC) designed to generate symmetrical and asymmetrical DC voltage configurations for a multilevel inverter (MLI) topology tailored for solar energy systems and electric vehicle (EV) charging. The MLI system's fundamental module produces 9-level, 21-level, and 31-level voltages using symmetrical and asymmetrical approaches, significantly reducing the number of switches and DC sources compared to traditional MLI topologies. The MOACFC supplies multiple output voltages simultaneously from a single solar generation input to the MLI, which employs an RNN-INC-based Maximum Power Point Tracking (MPPT) algorithm to maximize power extraction from photovoltaic (PV) arrays. The combined performance of the MLI and MOACFC has been rigorously tested, demonstrating excellent results in dynamic environments. The various inverters—9-level, 21-level, and 31-level—achieve total harmonic distortion (THD) of 9.36%, 3.92%, and 2.63%, respectively, using Nearest Level Control Pulse Width Modulation (NLCPWM). For EV charging applications, the proposed system significantly reduces THD in both voltage and current compared to conventional 2-level and 3-level inverters. With the proposed configuration using Level Shifted Pulse Width Modulation (LSPWM), voltage and current THD are reduced to 3.77% and 0.99%, respectively. In contrast, conventional 2-level inverters exhibit voltage and current THD of 15.63% and 3.5%, and conventional 3-level inverters show 10.3% and 2.1%. This reduction in THD enhances power quality delivered to the EV charger, improving charging efficiency and reducing electrical stress on the vehicle's battery system. The study includes the development and simulation testing of single-phase 9-level, 21-level, and 31-level inverters, as well as hardware testing of the 31-level asymmetric configuration. The results demonstrate that the proposed system not only improves power quality for solar generation and EV charging applications but also offers a more efficient and reliable alternative to conventional inverter topologies.