A Nonisolated Four-Port DC-DC Converter for Solar PV-Battery Integration in Bipolar Load Systems

Abstract

The article introduces a new four-port converter formulated for integration of Solar PV and battery into bipolar DC microgrid systems, achieving single-stage energy conversion. Distinguished by its improved power density, incorporating single inductor, the proposed circuit exhibits enhanced voltage boost in contrast to contemporary non-isolated multiport DC-DC converters. Notably, all input and output ports share a common reference ground. The symmetrical structure at the output inherently regulates both pole voltages, while ensuring inductor current control leveraging a simplified control strategy. Moreover, the proposed converter is capable of executing as a single-input-triple-output, dual-input-dual-output, or single-input-dual-output system based on the energy relationships between the source and the load. The article explores various operational modes and presents simulation results highlighting the effectiveness of the proposed circuit. © 2024 IEEE.