Robust CCFAD method for suppressing harmonic resonance of LCL grid-connected inverter in weak grid

被引:0
|
作者
Yang M. [1 ]
Yang J. [1 ]
Zhao T. [1 ]
Zheng C. [2 ]
Wei Y. [1 ]
机构
[1] School of Electrical Engineering and Automation, Henan Polytechnic University, Jiaozuo
[2] State Grid Henan Electric Power Research Institute, Zhengzhou
关键词
capacitive current feedback active damping; capacitive voltage feedback active damping; digital control delay; harmonic resonance; negative first-order inertia link;
D O I
10.15938/j.emc.2023.11.013
中图分类号
学科分类号
摘要
LCL filter grid connected inverter adopts capacitive current feedback active damping for network access control under weak current network. When the system resonance frequency is higher than 1 / 6 of the sampling frequency, the digital control delay will lead to poor robustness and even instability of grid connected inverter under the influence of wide-range varying grid impedance. Through analysis, it is pointed out that the capacitive current feedback active damping method is equivalent to the virtual impedance Zeq(s) connected in parallel at both ends of the filter capacitor, and the system instability is mainly caused by the negative resistance characteristic of Zeq(s). A robust method was proposed by using negative first-order inertia link for capacitive current feedback active damping. The inertia link was introduced into the capacitive current damping loop, and the frequency stability analysis method was used to discuss it in detail, and the design process of related parameters was further given. Theoretical analysis shows that this method can ensure that Zeq(s) is always in the range of positive resistance characteristics within the effective range of the resonance frequency of the LCL filter, which not only improves the stability margin of the system, but also suppresses the harmonic resonance of the grid-connected system. In addition, this method has better flexibility. If capacitive voltage feedback active damping control is used and phase-locked, the use of a set of current sensors is saved. Finally, effectiveness of the proposed method is verified through experiments. © 2023 Editorial Department of Electric Machines and Control. All rights reserved.
引用
收藏
页码:125 / 137
页数:12
相关论文
共 21 条
  • [1] ZHENG Zheng, HUANG Xu, YANG Ming, Et al., Grid voltage feedforward control strategy for weak grid based on complex filter, Power System Protection and Control, 46, 24, (2018)
  • [2] ZHENG Zheng, HUANG Xu, YANG Ming, Et al., Stability analysis and improvement for LCL filter grid-connected inverter using inverter-side current feedback, Power System Protection and Control, 47, 19, (2019)
  • [3] YANG Longyue, GUO Rui, ZHANG Le, Et al., Improvement strategy for grid-connected current quality of an inverter under non-ideal grid conditions, Power System Protection and Control, 48, 15, (2020)
  • [4] LISERRE M, BLAABIJERG F, HANSEN S., Design and control of an LCL-filter-based three-phase active rectifier, IEEE Transactions on Industry Applications, 41, 2, (2005)
  • [5] QIU Zhiling, YANG Enxing, KONG Jie, Et al., Current loop control approach for LCL-based shunt active power filter, Proceedings of the CSEE, 29, 18, (2009)
  • [6] XU Jinming, XIE Shaojun, XIAO Huanfeng, Research on control mechanism of active damping for LCL filters, Proceedings of the CSEE, 32, 9, (2012)
  • [7] DANNEHL J, LISERRE M, FUCHS F W., Filter-based active damping of voltage source converters with LCL filter, IEEE Transactions on Industrial Electronics, 58, 8, (2011)
  • [8] ZHANG Shao, JIANG Shuai, LU Xi, Et al., Resonance issues and damping techniques for grid-connected inverters with long transmission cable, IEEE Transactions on Power Electronics, 29, 1, (2014)
  • [9] (2016)
  • [10] PAN Hongbin, OU Sicheng, LIU Linhai, Et al., Influence of delay and stable domain analysis and design based on digital single-loop control of grid-connected inverter with LCL-filter, Automation of Electric Power Systems, 40, 6, (2016)