Grid-Following Voltage Source Converters: Basic Schemes and Current Control Techniques to Operate With Unbalanced Voltage Conditions

The growing relevance of voltage source converters (VSCs), and the deep impact they have on the development and maintenance of the electrical grid, increase the necessity of further research on how to deal with nonideal grid conditions from the VSCs control. This paper is aimed to summarize the basi...

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Detalhes bibliográficos
Autores: Montero-Robina, Pablo, Rouzbehi, Kumars, Gordillo Álvarez, Francisco, Pou, Josep
Formato: artículo
Estado:Versión publicada
Fecha de publicación:2021
País:España
Recursos:Universidad de Sevilla (US)
Repositorio:idUS. Depósito de Investigación de la Universidad de Sevilla
OAI Identifier:oai:idus.us.es:11441/136949
Acesso em linha:https://hdl.handle.net/11441/136949
https://doi.org/10.1109/OJIES.2021.3121764
Access Level:acceso abierto
Palavra-chave:Current controller
Current reference generation
Negative sequence
Unbalanced grid
Voltage source converter (VSC).
Descrição
Resumo:The growing relevance of voltage source converters (VSCs), and the deep impact they have on the development and maintenance of the electrical grid, increase the necessity of further research on how to deal with nonideal grid conditions from the VSCs control. This paper is aimed to summarize the basic techniques and schemes that might be required for a grid-connected VSC to work under these conditions: grid synchronization schemes, sequence decomposition, current reference generation, and current controllers. At the same time, some alternative schemes that improves the basic ones are cited. Modelling and the two typical current controllers design and tuning under stationary and synchronous reference frames are also exhibited. Given the importance of the current control stage in the VSC behaviour, five control schemes, designed to track negative sequence currents, are shown and tested in simulation and experiments. According to the experiments, it is shown that the standard proportional-resonant controller achieves the best performance in negative sequence tracking due to the robustness of its non-ideal version, the improved implementation thanks to the delta operator, and the non-dependence on grid-synchronization schemes. Alternatively, one approach based on dual synchronous reference frame is also highlighted for easiness of implementation and good performance