In this paper a new, general methodology for leakage and ground fault currents evaluation in grid-connected, low-voltage DC microgrids is introduced. Modified sequence equivalent circuits are considered, generalizing traditional AC power systems analysis. For three-phase systems, a modified Clarke transformation and, for two-wire systems, a modified modal transformation are introduced. These transformations, applied to a hybrid AC/DC system, allow building a modal equivalent circuit of the whole system, constituted by two coupled sub-circuits. The proposed equivalent circuits are intended as general time-domain models and are suitable for both steady-state and transient analysis. This approach highlights the whole system topology and allows evaluating the influence of active and passive components on leakage and ground fault currents. The proposed methodology is experimentally verified and, successively, applied to a hybrid AC/DC microgrid including DERs and storage devices.

VSC-based LVDC distribution network with DERs: Equivalent circuits for leakage and ground fault currents evaluation

Negri S.;Tironi E.;
2021-01-01

Abstract

In this paper a new, general methodology for leakage and ground fault currents evaluation in grid-connected, low-voltage DC microgrids is introduced. Modified sequence equivalent circuits are considered, generalizing traditional AC power systems analysis. For three-phase systems, a modified Clarke transformation and, for two-wire systems, a modified modal transformation are introduced. These transformations, applied to a hybrid AC/DC system, allow building a modal equivalent circuit of the whole system, constituted by two coupled sub-circuits. The proposed equivalent circuits are intended as general time-domain models and are suitable for both steady-state and transient analysis. This approach highlights the whole system topology and allows evaluating the influence of active and passive components on leakage and ground fault currents. The proposed methodology is experimentally verified and, successively, applied to a hybrid AC/DC microgrid including DERs and storage devices.
DC system Grounding
DERs
Ground fault analysis
Leakage currents
LVDC distribution
Modal equivalent circuits
File in questo prodotto:
File Dimensione Formato  
1-s2.0-S0960148121008314-main.pdf

Accesso riservato

: Publisher’s version
Dimensione 1.59 MB
Formato Adobe PDF
1.59 MB Adobe PDF   Visualizza/Apri
Equivalent circuits for leakage and ground fault currents evaluation_PrePrint.pdf

embargo fino al 01/06/2023

: Post-Print (DRAFT o Author’s Accepted Manuscript-AAM)
Dimensione 673.75 kB
Formato Adobe PDF
673.75 kB Adobe PDF   Visualizza/Apri

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11311/1198159
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 3
  • ???jsp.display-item.citation.isi??? 3
social impact