Adaptive Control Method for Improving Current Quality of Grid-connected Inverter Under Weak Grid

被引：0
|
作者：
Ma X. [1 ]
Xu R. [1 ]
Chen M. [2 ]
Fu A. [1 ]
Yang S. [1 ]
机构：
[1] Electric Power Research Institute of Chongqing Electric Power Company, North New District, Chongqing
[2] School of Electrical Engineering, Chongqing University, Shapingba District, Chongqing
来源：
Dianwang Jishu/Power System Technology | 2019年 / 43卷 / 08期
关键词：
Adaptive robust control; Grid-connected inverters; LCL filter; Weak grid;
D O I：
10.13335/j.1000-3673.pst.2018.2376
中图分类号：
学科分类号：
摘要：
Distribution network has obvious weak grid characteristics, especially at its end, that is, it has a large line impedance and a relatively severe grid voltage distortion. When the grid impedance changes widely, in order to improve the robust stability of grid-connected inverter, suppression of the grid voltage distortion is often sacrificed, resulting in decrease in grid-connected current quality. Aiming at this problem, this paper firstly establishes a robust model of the grid-connected inverters in weak grids, and analyzes the influence mechanism of grid impedance and grid voltage distortion on grid-connected inverter stability and grid-connected current quality. On this basis, this paper proposes an adaptive robust H∞ control scheme, which does not need to measure the grid impedance online. The control parameters do not change with the variation of the grid impedance, realizing robust stability of the system for wide changes of the grid impedance, and optimal suppression of grid voltage distortion, and improving grid-connected current quality. Then the paper presents the calculation method of each reference quantity and the design method of control parameters. Finally, validity of the theoretical analysis and the proposed control method is verified with experiments. © 2019, Power System Technology Press. All right reserved.
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页码：2892 / 2900
页数：8
相关论文
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