Multiobjective Coordinated Control Strategy for Grid-Connected Inverter under Unbalanced Voltage Conditions
Publication: Journal of Energy Engineering
Volume 146, Issue 3
Abstract
To improve grid-connected inverter operation performance, a power oscillation and current harmonic suppression coordinate control strategy that considers the problem of overcurrent is proposed in this work. First, the internal relationship between power fluctuation suppression and current balance is analyzed, and then, combining dynamic regulation of the active and reactive power settings, the peak value of the grid-connected current is limited within a safe range. Second, a simplified Fourier transform algorithm is proposed for the detection of fundamental positive and negative sequence vector components and band-pass filtering the three-phase input signals. By simplifying the transform and introducing a recursion algorithm, the online computational complexity is reduced and the controller based on this algorithm is used as an inner current loop regulator. Finally, the controller was investigated using simulations, and experimental results indicated that the output power quality of the grid-connected inverter under unbalanced grid voltages can be substantially improved.
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Data Availability Statement
All data, models, and code generated or used during the study appear in the published article.
Acknowledgments
This work is supported by the National Natural Science Foundation of China (Grant No. 61873025) and Fundamental Research Funds for the Central Universities (Grant No. FRF-OT-18-008).
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Published In
Journal of Energy Engineering
Volume 146 • Issue 3 • June 2020
Copyright
©2020 American Society of Civil Engineers.
History
Received: May 1, 2019
Accepted: Oct 21, 2019
Published online: Mar 11, 2020
Published in print: Jun 1, 2020
Discussion open until: Aug 11, 2020
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