DOI QR코드

DOI QR Code

Stability Analysis Using G-Parameters of Converters Constituting DC Microgrid and Stability Enhancement Through Virtual Impedance

G-parameter를 이용한 직류 마이크로그리드의 컨버터 상호 안정도 분석 및 가상 임피던스를 이용한 안정도 향상

  • Lee, Jae-Suk (Dept. of Electrical Eng., HYPEC-EECS lab., Hanyang Univ.) ;
  • Lee, Gi-Young (Dept. of Electrical Eng., HYPEC-EECS lab., Hanyang Univ.) ;
  • Kim, Rae-Young (Dept. of Electrical Eng., HYPEC-EECS lab., Hanyang Univ.)
  • Received : 2018.06.22
  • Accepted : 2018.08.18
  • Published : 2018.10.20

Abstract

DC microgrid system composed of multiple converters has a tendency to make the system unstable due to the interaction of converters. To solve this problem, in this paper, the interaction between cascaded converters with LC input filter is analyzed with impedance modeling using g-parameter. The input impedance and the output impedance of the system can be obtained through this technique. The stability of the system can be determined by applying Middlebrook's stability criterion to the impedance. Virtual impedance is added to the controller to enhance stability. The validity of the analysis is verified by the result of several simulations and experiments.

Keywords

References

  1. Y. Ito, Y. Zhongqing, and H. Akagi, "DC micro-grid based distribution power generation system," in Power Electronics and Motion Control Conference(IPEMC), 2004.
  2. S. Anand, B. G. Fernandes, and J. Guerrero, “Distributed control to ensure proportional load sharing and improve voltage regulation in low-voltage DC microgrid,” IEEE Trans. Power Electron., Vol. 28, No. 4, pp. 1900-1913, Aug. 2012. https://doi.org/10.1109/TPEL.2012.2215055
  3. T. Dragicevic, X. Lu, J. Vasquez, and J. Guerrero, "DC microgrids part 1: A review of control strategies and stabilization techniques," IEEE Trans. Power Electron., Vol. 31, No. 7, pp. 4876-4891. Jan. 2016. https://doi.org/10.1109/TPEL.2015.2478859
  4. Q. Shafiee, T. Dragicevic, J. C. Vasquez, J. M. Guerrero, "Modeling, stability analysis and active stabilization of multiple DC-microgrid cluster," in Energy Conference (ENERGYCON), 2014.
  5. Z. Zhao, J. Hu, H. Xue, R. Huang, X. Li, and X. Zhang, "Large signal stability analysis of DC microgrid under droop control with constant power load," in Chinese Automation Congress (CAC), 2017.
  6. G. Lin, Z. Wang, G. Huang, Y. Li, C. Li, and Y. Luo, "Impedance-model-based stability analysis of DC microgrid," Industrial Electronics Society, IECON, 2017.
  7. X. Zhang, W. L. Ming, Q. C. Zhong, and X. B. Ruan, "Stability of a cascaded DC system via adding a virtual impedance in series with the load converter," in Symposium on Power Electronics for Distributed Generation Systems(PEDG), 2015.
  8. X. Zhang, Q. C. Zhong, and W. L. Ming, “Stabilization of cascaded DC/DC converters via adaptive seriesvirtual impedance control of the load converter,” IEEE Trans. Power Electron., Vol. 31, No. 9, pp. 6057-6063, Sep. 2016. https://doi.org/10.1109/TPEL.2016.2524629
  9. X. Zhang, X. Ruan, and Q. C. Zhong, “Improving the stability of cascaded systems via shaping the input impedance of the load converter with a parallel or series virtual impedance,” IEEE Trans. Ind. Electron., Vol. 62, No. 12, pp. 7499-7512, Dec. 2015. https://doi.org/10.1109/TIE.2015.2459040
  10. C. Yoon, H. Bai, R. Beres, X. Wang, C. Bak, and F. Blaabjerg, “Harmonic stability assessment for multi-paralleled, grid-connected inverters,” IEEE Trans. Sustain. Energy, Vol. 7, No. 4, pp. 1388-1397, Oct. 2016. https://doi.org/10.1109/TSTE.2016.2551737
  11. S. Vesti, J. A. Oliver, R. Prieto, J. A. Cobos, J. Huusari, and T. Suntio, "Practical characterization of input-parallel-connected converters with a common input filter," in 2012 Twenty-Seventh Annual IEEE Applied Power Electronics Conference and Exposition (APEC), pp. 1845-1852, Feb. 2012.
  12. A. Aldhaheri and A. H. Etemadi, "Stabilization and performance preservation of DC-DC cascaded systems by diminishing output impedance magnitude," IEEE Trans. Industry Applications, Vol. 54, No. 2, pp. 1481-1489, Oct. 2017.
  13. R. D. Middlebrook, "Input filter considerations in design and application of switching regulators," IEEE Industry Applicat. Soc. Annu. Meeting, 1976 Record.
  14. C. M. Wildwirck, F. C. Lee, B. H. Cho, and B. Choi, "A method of defining the load impedance specification for a stable distributed power system," IEEE Trans. Power Electron., Vol 10, No. 3, pp. 280-285, May 1995.
  15. S. D. Sudhoff, S. F. Glover, P. T. Lamm, D. H. Schmucker, and D. E. Delisle, “Admittance space stability analysis of power electronic system,” IEEE Trans. Aerosp. Electron., Vol. 36, No. 3, pp. 965-973, Jul. 2000. https://doi.org/10.1109/7.869516
  16. X. Lu, K. Sun, J. M. Guerrero, J. C. Vasquez, L. Huang, and J. Wang, “Stability enhancement based on virtual impedance for DC microgrids with constant power load,” IEEE Trans. Smart Grid, Vol. 6, No. 6, pp. 2770-2783, Aug. 2015. https://doi.org/10.1109/TSG.2015.2455017
  17. M. N. Hussain, R. Mishra, V. Agarwal, "A self-switched virtual impedance based stabilization method for a droop controlled DC microgrid with constant power loads and input load filters," Power Electronics, Drives and Energy Systems(PEDES), pp. 1-6, Dec. 2016.
  18. R. W. Erickson and D. Maksimovic, Fundamentals of power electronics: Second Edition, Springer Publishers, 2001.