Citation: Souza Junior, M.E.T.;
Freitas, L.C.G. Power Electronics for
Modern Sustainable Power Systems:
Distributed Generation, Microgrids
and Smart Grids—A Review.
Sustainability 2022, 14, 3597.
https://doi.org/10.3390/su14063597
Academic Editors: Taha Selim Ustun
and Suhail Hussain
Received: 18 February 2022
Accepted: 14 March 2022
Published: 18 March 2022
Publisher’s Note: MDPI stays neutral
with regard to jurisdictional claims in
published maps and institutional affil-
iations.
Copyright: © 2022 by the authors.
Licensee MDPI, Basel, Switzerland.
This article is an open access article
distributed under the terms and
conditions of the Creative Commons
Attribution (CC BY) license (https://
creativecommons.org/licenses/by/
4.0/).
sustainability
Review
Power Electronics for Modern Sustainable Power Systems:
Distributed Generation, Microgrids and Smart Grids—A Review
Marcus Evandro Teixeira Souza Junior and Luiz Carlos Gomes Freitas *
Faculty of Electrical Engineering, Federal University of Uberlandia, Uberlândia 38400-902, Brazil;
marcus11jr@hotmail.com
* Correspondence: lcgfreitas@ufu.br
Abstract: This work presents and discusses the application of power electronics for the integration
of several distributed generation sources, as well as those related to it, the microgrids and the
smart grids, to the power sector. Trends and challenges are addressed for the area of study and an
embracing overview of the main technologies and techniques is presented for future investigation.
As there are many power electronics devices available for employment, in each one of these crucial,
modern, sustainable electrical systems, it is important for students, researchers and professionals to
understand and compare the state of the art of them all, for the right choice in their respective uses.
These apparatuses not only allow grid matching, but also provide new functions that enhance these
artifacts’ operations, and of the entire power system. Thus, in this paper, the relationship between
power electronics and distributed generation is detailed, with the role and classification of each static
converter for the improved operation of wind power, photovoltaic systems, fuel cells, small hydro
and microturbines exposed. While the first two are more widely covered in the literature, the last
three are rarely discussed and differentiated, in terms of their power electronics interfaces. Then, the
same is made for microgrids and smart grids, also scarcely approached in other works, with regard
to the characteristics of the power converters applied, confirming their superior performances with
the use of power electronics. Finally, conclusions are given.
Keywords: distributed generation (DG); microgrids; power electronics; renewable energies; smart
grids; static converters
1. Introduction
Power electronics, the field where semiconductor equipment is studied and developed
for the efficient conversion of electrical energy, through advanced control methods, has
been playing an increasingly important role in the world. Their devices find applications in
the most varied areas of technology, involving electricity. Industrial, mobility and energy
sectors raise their productivities and improve the quality of their services when making
use of them [1].
At the same time, distributed generation (DG), mainly in the form of renewable ener-
gies, has aroused great interest in recent years, due to its admirable potential benefits, such
as reduction in the emission of greenhouse gases and pollution in general, improvements in
reliability and in power quality, private production of electricity, employment generation,
among others [2,3]. Its adoption, and that of its related technologies of microgrids and
smart grids, seems the right way to achieve the Sustainable Development Goal (SDG) 7 of
the United Nations’ 2030 Agenda, for ensuring “access to affordable, reliable, sustainable
and modern energy for all” [4]. It is not by chance that DG has expanded and penetrated all
the points of the power system. Indeed, the total installed capacity in the whole world of
the most acclaimed sources of DG, solar photovoltaic and wind power, grows exponentially,
with the former rising from about 72 GW to 710 GW, and the second from approximately
220 GW to 732 GW, between 2011 and 2020 [5].
Sustainability 2022, 14, 3597. https://doi.org/10.3390/su14063597 https://www.mdpi.com/journal/sustainability