Power electronics (PE) technology has become integral across various applications, playing a vital role in sectors worldwide. The integration of renewable energy (RE) into modern power grids requires highly efficient and reliable power conversion systems, especially with the increasing demand for grid controllability and flexibility. Advanced control and information technologies have established power electronics converters as essential enablers of large-scale RE generation. However, their widespread use has introduced challenges to conventional power grids, including reduced system inertia and stability issues. This article studies the critical role of power electronics in the grid integration of RE systems, addressing key technical challenges and requirements. A special focus is given to the integration of wind energy, solar photovoltaic, and energy storage systems. This paper reviews essential aspects of energy generation and conversion, including the control strategies for individual power converters and system-level coordination for large-scale energy systems. This article additionally includes grid codes that pertain to wind and photovoltaic systems, as well as power conversion and control technologies. Finally, it outlines the future research directions, aimed at overcoming emerging challenges and advancing the seamless integration of RE systems into the grid, thereby contributing to the development of more sustainable and resilient energy infrastructure.

In this study, a new switched-capacitor-based seven-level inverter topology with a photovoltaic system is presented. The proposed topology requires a smaller number of devices and has the ability to self-balance the voltage across the capacitor. The proposed topology configuration is simple and has the ability to extend to higher levels of voltage. This multilevel inverter topology is suitable for low- and medium-voltage applications with photovoltaic (PV) system integration. To improve the PV system efficiency as an input of a DC–DC boost converter, a Fuzzy logic-based maximum power point controller technique is used. A PV system with a DC–DC boost converter integrates with the proposed seven-level inverter topology. The anti-predatory particle swarm optimization (APSO) technique is used to solve the non-linear transduction equations of the seven-level PV switched-capacitor-based multilevel inverter (7L−PV−SCMLI) topology. The proposed APSO is described to minimize the harmonics in the multilevel inverter (MLIs), which is a complex optimization problem involving a non-linear transcendental equation. Furthermore, APSO can be applied in order to solve non-linear transcendental equations for all symmetrical and asymmetrical MLIs that have equal and non-equal DC sources. The APSO-based selected harmonic elimination (SHE) technique obtained the best switching angle value, and the optimized obtained switching angles reduced the total harmonic distortion (THD) of 7L−PV−SCMLI.

This paper discloses a novel switched capacitor (SC)-based 7-level inverter with a single DC source. The proposed inverter has the ability to self-balancing the voltage of the capacitor without using a closed-loop voltage balancing circuit. Two capacitors are equally charged by the input source owing to the series-parallel charging and discharging continuously in a full cycle. The proposed 7-level SC inverter requires less number of switches, driver diodes, and capacitors and a lower number of semiconductor switches than most recently developed topologies. Furthermore, four out of the eight switches operate at the fundamental frequency, which simplifies the control scheme. A fundamental frequency switching scheme is used to control the output of the inverter. The self-balancing and voltage-boosting features of the proposed structure are validated on MATLAB/software platform and verified experimentally.