Transformerless Six-Leg Single-Phase to Split-Phase Power Converter with Grid Disturbance Mitigation

Manoel S. de  Oliveira Neto; Cursino B. Jacobina; Bruna S. Gehrke; Alan S. Felinto; Isaac S. de Freitas; Lucas F. M. de Lucena

doi:10.18618/REP.e202627

Authors

Manoel S. de Oliveira Neto Federal University of Campina Grande https://orcid.org/0009-0003-3011-7189
Cursino B. Jacobina Federal University of Campina Grande https://orcid.org/0000-0003-1111-6087
Bruna S. Gehrke Federal Rural University of Pernambuco https://orcid.org/0000-0001-8723-806X
Alan S. Felinto State University of Paraíba https://orcid.org/0000-0002-3728-1710
Isaac S. de Freitas Federal University of Paraíba
Lucas F. M. de Lucena Federal University of Campina Grande https://orcid.org/0009-0001-6112-9647

DOI:

https://doi.org/10.18618/REP.e202627

Keywords:

AC-DC-AC Converter, grid disturbance mitigation, space vector modulation, six-leg, split-phase system, single-phase three-wire converter, transformerless

Abstract

This article proposes a transformerless six-leg single-phase to two-phase AC-DC-AC converter for applications in single-phase three-wire distribution systems, also known as single split-phase systems. Featuring an architecture built upon a pair of three-leg converters, and employs space vector pulse-width modulation to synthesize the output voltages, this modulation scheme reduces harmonic content. Under severe load unbalances, the implemented control scheme successfully preserves fixed amplitude and frequency for the output voltages, while ensuring a predominantly fundamental grid current with low harmonic distortion and a high power factor, including when supplying nonlinear loads. In addition, the proposed topology can mitigate grid disturbances, such as voltage sags and swells, maintaining the load voltages with constant amplitude and frequency and preserving a high grid-side power factor under voltage disturbances, as well as nonlinear and unbalanced loads conditions. When contrasted with the conventional four-leg AC-DC-AC converter, the proposed converter mitigates grid current harmonic distortion while reducing semiconductor losses. The validity of the entire system are thoroughly confirmed through simulation and experimental evaluations.

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Author Biographies

Manoel S. de Oliveira Neto, Federal University of Campina Grande

was born in Santa Rita, Paraíba, Brazil, in October 1993. He received the B.S. and M.S. degrees in electrical engineering from the Federal University of Paraíba (UFPB) in 2020 and 2023, respectively. He is currently pursuing the Ph.D. degree in electrical engineering at the Federal University of Campina Grande (UFCG). His research interests include power electronics, modulation techniques (SVPWM), power quality systems, active power filters, control of grid-connected converters and multilevel converters.

Cursino B. Jacobina, Federal University of Campina Grande

was born in Correntes, Brazil, in 1955. He received the B.S. degree in electrical engineering from the Federal University of Paraíba, Campina Grande, Brazil, in 1978, and the Diplôme d'Etudes Approfondies and the Ph.D. degrees in electrical engineering from the Institut National Polytechnique de Toulouse, Toulouse, France, in 1980 and 1983, respectively. From 1978 to March 2002, he was with the Department of Electrical Engineering, Federal University of Paraíba, João Pessoa, Brazil. Since April 2002, he has been with the Department of Electrical Engineering, Federal University of Campina Grande, Campina Grande, where he is currently a Professor of electrical engineering. His research interests include electrical drives, power electronics, and energy systems.

Bruna S. Gehrke, Federal Rural University of Pernambuco

received the B.S. degree in electrical engineering from the Regional University of Northeast of Rio Grande do Sul (UNIJUÍ) in 2016, and the M.S. and D.Sc. degrees in electrical engineering from the Federal University of Campina Grande in 2019 and 2023, respectively. She is currently a Professor at the Federal Rural University of Pernambuco. Her research interests include multilevel converters, electrical drives, and modulation techniques.

Alan S. Felinto, State University of Paraíba

received the B.S., M.S. and D.Sc. degrees in electrical engineering from Federal University of Campina Grande, Campina Grande, Brazil, in 2017, 2018 and 2022, respectively. Since 2025, he has been a professor at the State University of Para´ıba. His current research interests include power electronics, renewable energy systems, and active power filters.

Isaac S. de Freitas, Federal University of Paraíba

received a Doctorate (2007), M.Sc. (2005), and B.Sc. (2004) in Electrical Engineering from the Federal University of Campina Grande (UFCG). From September 2006 to August 2007, he was at the EMPE (Advanced Electrical Machine and Power Electronic Laboratory) at Texas A\&M University, in Texas (USA), participating in the CNPq's sandwich doctoral program abroad. From February to May 2008, he was a professor at CEFET-Petrolina, UnED-Floresta. Since June 2008, he has been a professor at the Federal University of Paraíba (UFPB), where he currently holds the position of Full Professor in the Department of Electrical Engineering. His research interests include electrical machines, electrical machine drives, static converters, and their applications in power systems.

Lucas F. M. de Lucena, Federal University of Campina Grande

was born in João Pessoa, Paraíba, Brazil, in 1997. He received the B.S. and M.S degree in Electrical Engineering from the Federal University of Paraíba, João Pessoa, Brazil, in 2021 and 2023, respectively. He is currently working toward the Ph.D. degree in Electrical Engineering with the Federal University of Campina Grande, Campina Grande, Brazil, and since 2026, he has been a professor at the Federal Institute of Paraíba. His research interests include power electronics, power quality systems and electrical drives.

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