Multiport Y-Converter for Three-Phase AC Grid Integration with DC Systems

The challenges associated with the escalating de-mand for electrical energy and environmental concerns tied to traditional energy sources underscore the need for greater penetration of renewable energy sources. To ensure stable and reliable energy production, energy storage systems and an inter-face with the AC grid can compensate for the intermittent nature of renewable sources. Hence, multiport converters are proposed to consolidate various energy ports into a single hub, enhancing system efficiency and power density. This paper proposes a single-stage non-isolated multiport converter to interface the three-phase AC grid with DC systems. The proposed converter features buck-boost capability and bidirectional power flow at all ports, enabling it to directly interface with a wide range of DC systems. Additionally, the absence of bulky intermediate DC-link capacitors and transformers in the proposed topology contributes to improved power density and reduced costs. The paper presents the converter's operation and analysis, along with an evaluation of semiconductor stresses and losses. Finally, simulation and experimental results are presented to highlight the converter's performance under different operating conditions.