Please use this identifier to cite or link to this item: https://hdl.handle.net/10356/80637
Title: Capacitor-voltage feedforward with full delay compensation to improve weak grids adaptability of LCL-filtered grid-connected converters for distributed generation systems
Authors: Li, Xiaoqiang
Fang, Jingyang
Tang, Yi
Wu, Xiaojie
Geng, Yiwen
Keywords: Capacitor-voltage Feedforward
Control Bandwidth
Engineering::Electrical and electronic engineering
Issue Date: 2017
Source: Li, X., Fang, J., Tang, Y., Wu, X., & Geng, Y. (2018). Capacitor-voltage feedforward with full delay compensation to improve weak grids adaptability of LCL-filtered grid-connected converters for distributed generation systems. IEEE Transactions on Power Electronics, 33(1), 749-764. doi:10.1109/TPEL.2017.2665483
Series/Report no.: IEEE Transactions on Power Electronics
Abstract: LCL-filtered grid-connected converters are widely used for distributed generation systems. However, the current regulation of such converters is susceptible to weak grid conditions, e.g., grid impedance variation and background harmonics. Paralleling multiple harmonic compensators (HCs) is a commonly used method to suppress the current distortion caused by grid background harmonics, but the control bandwidth should be wide enough to ensure system stability. In order to enhance the adaptability of LCL-filtered grid-connected converters under weak grid operation, this paper proposes an improved capacitorvoltage-feedforward control with full delay compensation. When used with converter-side current feedback, the proposed control can keep system low-frequency characteristic independent of grid impedance and provide a high-harmonic rejection capability without using additional HCs. Moreover, it completely avoids the design constraints of an LCL filter, i.e., ω τ <; ω 8 /6 is required for singleloop converter-side current control. Therefore, a higher resonant frequency can be designed to achieve a wider control bandwidth and to lower the current distortion caused by the paralleled filter capacitor branch. Experimental results are finally presented to verify the proposed control, which are also in good agreement with theoretical analysis.
URI: https://hdl.handle.net/10356/80637
http://hdl.handle.net/10220/50070
ISSN: 0885-8993
DOI: http://dx.doi.org/10.1109/TPEL.2017.2665483
Rights: © 2017 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works. The published version is available at: https://doi.org/10.1109/TPEL.2017.2665483.
Fulltext Permission: open
Fulltext Availability: With Fulltext
Appears in Collections:EEE Journal Articles

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