Advancements in multilevel inverter technologies for photovoltaic-Z-source based EV applications: A comprehensive analysis and future directions

Abstract

Global demand for electricity has risen, driving a shift toward sustainable energy sources like Photovoltaic (PV) systems. Despite their efficiency challenges compared to traditional fuels, significant investments and research are advancing the technology. This paper investigates multilevel inverter topologies, with a focus on Z-source technology for high-power PV applications. The study begins with an overview of the growing demand for alternative energy sources and the role of multilevel inverters in enhancing PV system performance. It discusses prominent multilevel inverter topologies, such as Neutral Point Clamped (NPC) and Cascaded H-Bridge (CHB) inverters, as well as control techniques including Pulse Width Modulation (PWM) and Predictive Control. Furthermore, it explores the functionality of Z-source inverters both with and without PV systems, highlighting their ability to provide voltage boosting, fault tolerance, and improved power quality. For load purposes, Electric Vehicle (EV) charging has been incorporated. The paper uses MATLAB/Simulink to compare multilevel inverter configurations and finds that the CHB inverter with Z-source is superior for PV applications due to its lower Total Harmonic Distortion (THD) and reduced semiconductor usage. The study also simulates a hybrid storage system with batteries and supercapacitors. The paper concludes with insights into future research directions, advanced control strategies, optimization techniques, and grid integration methods. These avenues promise further enhancement of efficiency, reliability, and grid compatibility for multilevel inverters in PV systems. Overall, this research contributes to the selection of optimal multilevel converter topologies for improving the performance of PV systems and advancing the integration of renewable energy into the electrical grid. The findings offer valuable insights for researchers, practitioners, and policymakers working toward a sustainable energy future.