This paper presents an innovative and effec-tive linear current regulator for grid-connected convertersinterfaced by an LCL filter. The proposed scheme entailsthe use of voltages measured at the terminals of the out-put filter capacitors as feedforward signals to be includedin a classical structure of proportional–resonant (PR) con-troller. Processing these signals by an opportune filterK(s), the resonance effects characterizing the LCL filter areneutralized and the impact of the grid impedance’s varia-tions on the converter’s performances is greatly reduced.The proposed solution simplifies the controller’s design,whose gains are obtained by a straightforward mathemat-ical formula which prevents complex root locus analyses.Moreover, for a given phase margin, the proposed tech-nique ensures the achievement of maximum possible band-width of closed-loop system, sidestepping the guessworktypical of the conventional methods used for selectingthe crossover frequency. Conclusions are supported by adetailed mathematical analysis and validated by laboratoryresults obtained with a 7.5-kW three-phase inverter proto-type connected to

Designing Inverters’ Current Controllers with Resonance Frequencies Cancellation

CECATI, Carlo;
2016-01-01

Abstract

This paper presents an innovative and effec-tive linear current regulator for grid-connected convertersinterfaced by an LCL filter. The proposed scheme entailsthe use of voltages measured at the terminals of the out-put filter capacitors as feedforward signals to be includedin a classical structure of proportional–resonant (PR) con-troller. Processing these signals by an opportune filterK(s), the resonance effects characterizing the LCL filter areneutralized and the impact of the grid impedance’s varia-tions on the converter’s performances is greatly reduced.The proposed solution simplifies the controller’s design,whose gains are obtained by a straightforward mathemat-ical formula which prevents complex root locus analyses.Moreover, for a given phase margin, the proposed tech-nique ensures the achievement of maximum possible band-width of closed-loop system, sidestepping the guessworktypical of the conventional methods used for selectingthe crossover frequency. Conclusions are supported by adetailed mathematical analysis and validated by laboratoryresults obtained with a 7.5-kW three-phase inverter proto-type connected to
File in questo prodotto:
File Dimensione Formato  
07378476.pdf

solo utenti autorizzati

Tipologia: Documento in Versione Editoriale
Licenza: Creative commons
Dimensione 1.58 MB
Formato Adobe PDF
1.58 MB Adobe PDF   Visualizza/Apri   Richiedi una copia
Pubblicazioni consigliate

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/11697/94333
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 43
  • ???jsp.display-item.citation.isi??? 35
social impact