A comprehensive review of hybrid energy systems utilizing multilevel inverters with minimal switch count

A feasible and efficient resolution to the challenges posed by the dependence of renewable energy sources (RES) on weather conditions and their intermittent behavior is the adoption of a hybrid energy system (HES). This study thoroughly investigates HES, incorporating an energy storage system to enhance RES integration into the power grid. HES integrates more than two renewable or non-renewable sources, thereby enhancing system stability and efficiency. The article delivers a comprehensive overview of HES, covering aspects such as system architecture, power converter structures, various energy storage systems and optimization objectives. Inverters, as a critical component, need to be selected judiciously for the system. Multilevel inverters (MLI) are favored for renewable energy integration, particularly over two-level converters, owing to their lower harmonic injection at low switching frequencies and suitability for high-power applications. The reduced switch multilevel inverter (RSMLI) has garnered notable interest in power conditioning for renewable energy sources. This article explores various reduced switch structures, comparing them based on the number of switches, drivers, diodes, capacitors and total blocking voltage for HES. The review underscores the technical advantages, future prospects and challenges associated with MLI-based HES. Cost and reliability pose major concerns in HES development, and this article delves into objectives related to reliability and cost optimization. Aiming to be a comprehensive resource, the article serves as a singular reference point for researchers in the realm of MLI-based HES.

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