High-Pass-Filter-Based Virtual Impedance Control for LCL-filtered Inverters Under Weak Grid


Vol. 18, No. 6, pp. 1780-1790, Nov. 2018
10.6113/JPE.2018.18.6.1780


PDF     Full-Text

 Abstract

Voltage feed-forward control (VFFC) is widely used in LCL-type grid-tied inverters due to its advantages in terms of disturbance rejection performance and fast dynamic response. However, VFFC may worsen the stability of inverters under weak grid conditions. It is revealed in this paper that a large phase-lag in the low-frequency range is introduced by VFFC, which reduces the phase margin significantly and leads to instability. To address this problem, a novel virtual-impedance-based control, where a phase-lead is introduced into the low-frequency area to compensate for the phase lag caused by VFFC, is proposed to improve system stability. The proposed control is realized with a high-pass filter, without high-order-derivative components. It features easy implementation and good noise immunity. A detailed design procedure for the virtual impedance control is presented. Both theoretical analysis and experimental results verify the effectiveness of the control proposed.


 Statistics
Show / Hide Statistics

Cumulative Counts from September 30th, 2019
Multiple requests among the same browser session are counted as one view. If you mouse over a chart, the values of data points will be shown.



Cite this article

[IEEE Style]

J. Wang, Y. Xing, L. Zhang, H. Hu, T. Yang, D. Lu, "High-Pass-Filter-Based Virtual Impedance Control for LCL-filtered Inverters Under Weak Grid," Journal of Power Electronics, vol. 18, no. 6, pp. 1780-1790, 2018. DOI: 10.6113/JPE.2018.18.6.1780.

[ACM Style]

Jiangfeng Wang, Yan Xing, Li Zhang, Haibing Hu, Tianyu Yang, and Daorong Lu. 2018. High-Pass-Filter-Based Virtual Impedance Control for LCL-filtered Inverters Under Weak Grid. Journal of Power Electronics, 18, 6, (2018), 1780-1790. DOI: 10.6113/JPE.2018.18.6.1780.