Optimal Multiobjective Control of Low-Voltage AC Microgrids: Power Flow Regulation and Compensation of Reactive Power and Unbalance

The presence of single-phase distributed generators unevenly injecting active power in three-phase microgrids may create undesired upstream current unbalance. Consequently, voltage asymmetry and even active power curtailment may occur in such networks with negative economic impact. Thus, this paper...

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Detalles Bibliográficos
Autores: Brandao, Danilo, Ferreira, Willian M., Alonso, Augusto M. S. [UNESP], Tedeschi, Elisabetta, Marafao, Fernando P. [UNESP]
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2020
País:Brasil
Institución:Universidade Estadual Paulista (UNESP)
Repositorio:Repositório Institucional da UNESP
Idioma:inglés
OAI Identifier:oai:repositorio.unesp.br:11449/196678
Acceso en línea:http://dx.doi.org/10.1109/TSG.2019.2933790
http://hdl.handle.net/11449/196678
Access Level:acceso abierto
Palabra clave:Reactive power
Voltage control
Load flow
Microgrids
Power generation
Optimization
Inverters
Distributed generation
microgrid
multiobjective
optimization
power quality
unbalance
Descripción
Sumario:The presence of single-phase distributed generators unevenly injecting active power in three-phase microgrids may create undesired upstream current unbalance. Consequently, voltage asymmetry and even active power curtailment may occur in such networks with negative economic impact. Thus, this paper proposes an optimal multiobjective approach to regulate the active and reactive power delivered by distributed generators driven by a three-layer hierarchical control technique in low-voltage microgrids. This method does not require previous knowledge of network parameters. The multiobjective algorithm is implemented in the secondary level achieving optimal dispatch in terms of maximizing the active power generation, as well as minimizing the reactive power circulation and current unbalance. By the existence of a utility interface three-phase converter placed at the point-of-common-coupling, the proposed control can regulate the power circulating among the microgrid phases, and the microgrid structure can withstand grid-connected and islanded operating modes. The path for interphase power circulation through the DC-link of the utility interface allows the multiobjective algorithm to achieve better results in terms of generation and compensation compared to the system without utility interface. The proposed method is assessed herein by computational simulations in a three-phase four-wire microgrid under realistic operational conditions.