The Virtual Resistor Used in Droop Control of DC Microgrids is a Series Loss-Free Resistor (SLFR)

Amanda L. Guerra; Ivo Barbi

doi:10.18618/REP.2023.3.0022

Authors

Amanda L. Guerra Federal University of Santa Catarina, Florianópolis – SC, Brazil
Ivo Barbi Federal University of Santa Catarina, Florianópolis – SC, Brazil

DOI:

https://doi.org/10.18618/REP.2023.3.0022

Abstract

The recently introduced series loss-free resistor (SLFR) is used to obtain the non-linear differential equations that describe the dynamic response of a DC-DC converter with virtual resistor and input LC filter, employed in the voltage droop control of DC microgrids. The equilibrium point and the stability criteria of the converter are presented. The results of the theoretical analysis are validated via computer simulation of largeamplitude transients for step change of the input voltage, the output current and the voltage reference signal. It is shown that the energy absorbed by the virtual resistor is not converted into heat but returned to the input stage by a power source. Thus, the paradox of the virtual resistor, which causes a voltage drop but does not consume power, is resolved. This is a theoretical study.

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Author Biographies

Amanda L. Guerra, Federal University of Santa Catarina, Florianópolis – SC, Brazil

was born in Marianao, Havana, Cuba. She received the B.S degree in Automation and Control systems engineering from the Technological University of Havana, Cuba, in 2018. She received the M.S degree in electrical engineering from the Federal University of Santa Catarina (UFSC), Florianópolis, Brazil, in 2021. She is currently a doctoral student at the Federal University of Santa Catarina, Brazil.

Ivo Barbi, Federal University of Santa Catarina, Florianópolis – SC, Brazil

(Life Fellow, IEEE) was born in Gaspar, Brazil. He received the B.S. and M.S. degrees in electrical engineering from the Federal University of Santa Catarina (UFSC), Florianópolis, Brazil, in 1973 and 1976, respectively, and the Dr. Ing. degree in electrical engineering from the Institute National Polytechnique de Toulouse (INPT), Toulouse, France, in 1979. He founded the Brazilian Power Electronics Society (SOBRAEP), the Brazilian Power Electronics Conference (COBEP), in 1990, and the Brazilian Power Electronics and Renewable Energy Institute (IBEPE), in 2016. He is currently a Researcher with the Solar Energy Research Center and a Professor Emeritus in electrical engineering with UFSC. Prof. Barbi received the 2020 IEEE William E. Newell Power Electronics Award. He served as an Associate Editor for the IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS and the IEEE TRANSACTIONS ON POWER ELECTRONICS for several years. He is currently Editor for the electrical engineering area of the SCIENTIFIC REPORTS JOURNAL (SpringerNature) and Associate Editor of the JOURNAL OF CONTROL, AUTOMATION AND ELECTRICAL SYSTEMS.

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