The Transactions of the Korean Institute of Power Electronics (전력전자학회논문지)

The Korean Institute of Power Electronics (전력전자학회)
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Droop Control for Parallel Inverers in Islanded Microgrid Considering Unbalanced Low-Voltage Line Impedances

마이크로그리드 독립 운전 모드시 저전압 불평형 선로 임피던스를 고려한 드룹 방식의 인버터 병렬 운전 제어 연구

  • Lim, Kyung-Bae (Dept. of Electrical Eng., Chungbuk National University) ;
  • Choi, Jaeho (Dept. of Electrical Eng., Chungbuk National University)
  • Received : 2013.02.08
  • Accepted : 2013.04.22
  • Published : 2013.08.20
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Abstract

This paper investigates the droop control of parallel inverters for an islanded mode of microgrid. Frequency and voltage droop control is one of power control and load demand sharing methods. However, although the active power is properly shared, the reactive power sharing is inaccurate with conventional method due to the unequal line impedances and the power coupling of active - reactive power. In order to solve this problem, an improved droop method with virtual inductor concept and a voltage and current controller properly designed have been considered and analyzed through the PSiM simulation. The performance of improved droop method is analyzed in not only low-voltage line but also medium voltage line.

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References

  1. T. Ackermann, G. Andersson, and L. Soder, "Electricity market regulations and their impact on distributed generation," in Conf. Rec of Electric Utility Deregulation and Restructuring and Power Technologies, pp. 608-613, 2000.
  2. T. Ackermann, G. Andersson, and L. Soder, "Distributed generation: A definition," Electric Power System Research, Vol. 57, pp. 195-204, 2001. https://doi.org/10.1016/S0378-7796(01)00101-8
  3. M. Marie, E. El-Saadany, and M. Salama, "Flexible distributed generation: (FDG)," IEEE Power Engineering Society Summer Meeting, Vol. 1, pp. 49-53, 2002.
  4. Distributed generation at Lawrence Berkeley National Laboratory (LBNL), http://der.lbl.gov.
  5. The Consortium for Electric Reliability Technology Solutions (CERTS), http://certs.lbl.gov.
  6. The GridWise alliance, http://www.gridwise.org/.
  7. Large Scale Integration of Micro-generation to Low Voltage Grids(MICROGRIDS), http://microgrids. power.ece.ntua.gr.
  8. Distributed Intelligence in Critical Infrastructures for Sustainable Power (CRISP), http://www.crisp.ecn.nl.
  9. Distributed Generation with High Penetration of Renewable Energy Sources (DISPOWER), http://www.dispower.org.
  10. A. Tuladhar, H. Jin, T. Unger, and K. Mauch, "Parallel operation of single phase inverter modules with no control interconnections," in Conf. Rec. of IEEE APEC 97, pp. 94-100, 1997.
  11. K. S. Parlak, M. Ozdemir and M. T. Aydemir "Active and reactive power sharing and frequency restoration in a distributed power systme consisting of two UPS units," Electrical Power and Energy Systems , Vol. 31, pp. 220-226, 2009. https://doi.org/10.1016/j.ijepes.2009.01.006
  12. K. D. Brabandere, B. Bolsens, J. V. Keybus, A. Woyte, J. Driesen, and R. A. Belmans, "Voltage and frequency droop control method for parallel inverters," IEEE Trans. on Power Electron., Vol. 22, No. 4, pp. 1107-1115, 2007. https://doi.org/10.1109/TPEL.2007.900456
  13. J. W. Kim, H. S. Choi, and B. H. Cho, "A novel droop method for converter parallel operation," IEEE Trans. on Power Electron., Vol. 22, No. 1, pp. 25-32, 2002.
  14. J. He and Y. W. Li, "An accurate reactive power sharing control strategy for DG units in a Microgrid," in Conf. of Rec. ICPE-ECCE Asia, pp. 551-556, 2011.
  15. Y. W. Li and C. N. Kao, "An accurate power control strategy for power-electronics-interfaced distributed generation units operation in a low voltage multibus microgrid," IEEE Trans. on Power Electron., Vol. 24, No. 12, pp. 2977-2988, 2009. https://doi.org/10.1109/TPEL.2009.2022828
  16. W. Yao, M. Chen, J. Matas, J. M. Guerrero, and Z. M. Qian, "Design and analysis of the droop control method for parallel inverters considering the impact of the complex impedance on the power sharing," IEEE Trans. on Ind. Electron., Vol. 58, No. 2, 2011.
  17. H. Gu, X. Guo, and W. Wu, "Accurate power sharing control for inverter-dominated autonomous microgrid," in Conf. of Rec. IPEMC -ECCE Asia, pp. 368-372, 2012.
  18. Y. Li and Y. W. Li, "Power management of inverter interfaced autonomous microgrid based on virtual frequency-voltage frame," IEEE Trans. on Smart Grid., Vol. 2, No. 1, pp. 30-40, 2011. https://doi.org/10.1109/TSG.2010.2095046
  19. N. Pogaku, M. Prodanovic, and T. C. Green, "Modeling, analysis and testing of autonomous operation of an inverter-based microgrid," IEEE Trans. on Power Electron., Vol. 22, No. 2, pp. 613-625, 2007. https://doi.org/10.1109/TPEL.2006.890003
  20. J. M. Guerrero, L. G. Vicuna, J. Matas, M. Castilla, and J. Miret, "Output impedance design of parallel-connected UPS inverters with wireless load-sharing control," IEEE Trans. on Ind. Electron., Vol. 52, No. 4, pp. 1126-1135, 2005. https://doi.org/10.1109/TIE.2005.851634
  21. J. He and Y. W. Li, "Analysis, design, and implementation of virtual impedance for power electronics interfaced distributed generation," IEEE Trans. Ind. Appl., Vol. 47, No. 6, pp. 2525-2538, 2011. https://doi.org/10.1109/TIA.2011.2168592
  22. M. N. Marwali and A. Keyhani, "Control of distributed generation systems—Part I: Voltages and current control," IEEE Trans. on Power Electron., Vol. 19, No. 6, pp. 1541-1550, 2004. https://doi.org/10.1109/TPEL.2004.836685
  23. D. N. Zmood and D. G. Holmes, "Stationary frame current regulation of PWM inverters with zero steady-state error," IEEE Trans. Power Electron., Vol. 18, No. 3, pp. 814-822, 2003. https://doi.org/10.1109/TPEL.2003.810852
  24. D. De and V. Ramanarayanan, "A proportional + multi resonant controller for three-phase four-wire high-frequency link inverter," IEEE Trans. Power Electron., Vol. 25, No. 4, pp. 899-906, 2010. https://doi.org/10.1109/TPEL.2009.2036012
  25. D. De and V. Ramanarayanan, "Decentralized parallel operation of inverters sharing unbalanced and non-linear loads," IEEE Trans. Power Electron., Vol. 25, No. 12, pp. 1126-1132, 2010. https://doi.org/10.1109/TPWRS.2009.2032325

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