Abstract
Due to its higher switching frequency current harmonics attenuation, the LCL filter is extensively adopted in Grid connected Converters (GcCs). To cope with its inherent resonance phenomena, the Capacitor Current Inner Loop Active Damping (CCIL-AD) is typically employed to actively damp the LCL filter resonant peak. However, the time delay (td) related to digital controllers modifies the Active Damping (AD) characteristics, resulting in reduced phase margin as well as poor dynamic and steady-state performances of the system. Moreover, high variations in the grid inductance, mainly under weak grid conditions, may threaten the system stability. In view of this, this paper proposes a robust design approach for voltage oriented PI control associated to CCIL-AD for LCL-filter-based Grid-connected Converters (LCL-GcCs). The aim of the considered approach is to ensure robust stability margins, fast transient response and reduced steady-state error even under severe grid inductance changes, digital time delay and LCL filter parameters variations. The proposed approach has been validated by simulation and experimental tests based on a 4-kW three-phase converter laboratory prototype. The obtained simulation and experimental results indicate the efficiency and the robustness of the proposed design approach.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
More From: International Journal of Electrical Power & Energy Systems
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.