With the increasing integration of renewable energy resources into modern electrical power systems, the development of distributed hybrid microgrids is becoming increasingly attractive because of their ability to operate in islanded mode and the coexistence of ac and dc buses. Power electronic converters, as critical technologies for these systems, increasingly require greater standardization and modularity. In this context, the modular universal converter topology emerged with the capability of operating as either a dc-dc or a dc-ac three-phase converter by featuring the same power stage with simple reconfiguration. This paper advances the MUC concept by introducing a modular dual-output hybrid converter that supplies a three-phase four-wire ac port and a regulated dc bus simultaneously using a single power-conversion stage, thereby replacing the conventional dual-output configuration based on separate dc-dc and dc-ac stages. The proposed architecture employs a modular arrangement of identical buck-boost cells in which three cells synthesize dc-biased sinusoidal phase voltages, while a fourth cell regulates the dc output and establishes the ac neutral by directly tying the neutral point to the positive dc terminal, enabling a common ground reference without galvanic isolation. Compared with previous MUC proposals that supply either ac or dc, the proposed converter delivers both simultaneously without reconfiguration. Simulation and laboratory measurements verify the converter operation using a regulated 200 V dc bus at a switching frequency of 62.5 kHz, demonstrating simultaneous delivery of 1 kW to the three-phase ac port and 800 W to the dc port with balanced sinusoidal ac waveforms, stable dc regulation, and fast, well-damped responses under both ac and dc load steps. These results demonstrate the feasibility of the proposed converter as a modular, single-stage dual-output solution for hybrid microgrids.
DOI: 10.1038/s41598-026-45619-6
Publication Date: 2026-03-25