DOI QR코드

DOI QR Code

A Decentralized Optimal Load Current Sharing Method for Power Line Loss Minimization in MT-HVDC Systems

  • Liu, Yiqi (College of Mechanical and Electrical Engineering, Northeast Forestry University) ;
  • Song, Wenlong (College of Mechanical and Electrical Engineering, Northeast Forestry University) ;
  • Li, Ningning (School of Electrical Engineering and Automation, Harbin Institute of Technology) ;
  • Bai, Linquan (Electrical Engineering and Computer Science Department, University of Tennessee) ;
  • Ji, Yanchao (School of Electrical Engineering and Automation, Harbin Institute of Technology)
  • Received : 2015.06.26
  • Accepted : 2016.07.01
  • Published : 2016.11.20

Abstract

This paper discusses the elimination of DC voltage deviation and the enhancement of load current sharing accuracy in multi-terminal high voltage direct current (MT-HVDC) systems. In order to minimize the power line losses in different parallel network topologies and to insure the stable operation of systems, a decentralized control method based on a modified droop control is presented in this paper. Averaging the DC output voltage and averaging the output current of two neighboring converters are employed to reduce the congestion of the communication network in a control system, and the decentralized control method is implemented. By minimizing the power loss of the cable, the optimal load current sharing proportion is derived in order to achieve rational current sharing among different converters. The validity of the proposed method using a low bandwidth communication (LBC) network for different topologies is verified. The influence of the parameters of the power cable on the control system stability is analyzed in detail. Finally, transient response simulations and experiments are performed to demonstrate the feasibility of the proposed control strategy for a MT-HVDC system.

Acknowledgement

Supported by : Central Universities

References

  1. K. Rouzbehi, A. Miranian, A. Luna, and P. Rodriguez, "DC voltage control and power sharing in multiterminal DC grids based on optimal DC power flow and voltage-droop strategy," IEEE J. Emerg. Sel. Topics Power Electron., Vol. 2, No. 4, pp.1171-1180, Dec. 2014. https://doi.org/10.1109/JESTPE.2014.2338738
  2. Z. Wei, Y. Yuan, X. Lei, H. Wang, G. Sun, and Y. Sun, "Direct-current predictive control strategy for inhibiting commutation failure in HVDC converter," in IEEE Trans. Power Syst., Vol. 29, No. 5, pp. 2409-2417, Sep. 2014. https://doi.org/10.1109/TPWRS.2014.2302010
  3. X. Shi, Z. Wang, B. Liu, Y. Liu, L. M. Tolbert, and F. Wang, "Characteristic investigation and control of a modular multilevel converter-based HVDC system under single-line-to-ground fault conditions," in IEEE Trans. Power Electron., Vol. 30, No. 1, pp. 408-421, Jan. 2015. https://doi.org/10.1109/TPEL.2014.2323360
  4. T. M. Haileselassie and K. Uhlen, "Impact of DC line voltage drops on power flow of MTDC using droop control," IEEE Trans. Power Syst., Vol. 27, No. 3, pp. 1441-1449, Aug. 2012. https://doi.org/10.1109/TPWRS.2012.2186988
  5. B. Sfurtoc, R. da Silva, and S. Chaudhary, "A MTDC system layout review based on system revenue a Kriegers Flak case study," Power Engineering, Energy and Electrical Drives (POWERENG), 2013 Fourth International Conference on, Istanbul, pp. 793-800, 2013.
  6. F. Deng and C. Z. Zhe, "An off-shore wind farm with DC grid connection and its performance under power system transients," 2011 IEEE Power and Energy Society General Meeting, pp. 24-29, 2011.
  7. C. Li, P. Zhan, J. Wen, M. Yao, N. Li, and W. J. Lee, "Offshore wind farm integration and frequency support control utilizing hybrid multiterminal HVDC transmission," IEEE Trans. Ind. Appl., Vol. 50, No. 4, pp. 2788-2797, Jul./Aug. 2014. https://doi.org/10.1109/TIA.2013.2293818
  8. J. Ren, K. Li, L. Sun, J. Zhao, Y. Liang, W. Lee, Z. Ding, and Y. Sun, "A coordination control strategy of voltage source converter based MTDC for off-shore wind farms," IEEE Industry Applications Society Annual Meeting, pp. 5-9, 2014.
  9. S. J. Shao and V. G. Agelidis, "Review of DC system technologies for large scale integration of wind energy systems with electricity grids," Energies, Vol. 3, No. 6, pp. 1303-1319, Jun. 2010. https://doi.org/10.3390/en3061303
  10. S. Rodrigues, R.T. Pinto, P. Bauer, and J. Pierik, "Optimal power flow control of VSC-based multiterminal DC network for off-shore wind integration in the north sea," IEEE J. Emerg. Sel. Topics Power Electron., Vol. 1, No. 4, pp.260-268, Dec. 2013. https://doi.org/10.1109/JESTPE.2013.2281917
  11. L. Wang and M. S.-N. Thi, "Power flow control of off-shore wind farms fed to power grids using an HVDC system," 2012 IEEE Industry Applications Society Annual Meeting (IAS), pp.7-11, 2012.
  12. X. Sun, Y.S. Lee, and D. H. Xu, "Modeling, analysis, and implementation of parallel multi-inverter systems with instantaneous average-current-sharing scheme," IEEE Trans. Power Electron., Vol. 18, No. 3, pp. 844-856, May. 2003. https://doi.org/10.1109/TPEL.2003.810867
  13. X. N. Lu, J. M. Guerrero, K. Sun, J. C. Vasquez, R. Teodorescu, and L. P. Huang. "Hierarchical control of parallel AC-DC converter interfaces for hybrid microgrids," IEEE Trans. Smart Grid, Vol. 5, No. 2, pp. 683-692, Mar. 2014. https://doi.org/10.1109/TSG.2013.2272327
  14. W. Wang and M. Barnes, "Power flow algorithms for multi-terminal VSC-HVDC with droop control," IEEE Trans. Power Syst., Vol. 29, No. 4, pp.1721-1730, Jul. 2014. https://doi.org/10.1109/TPWRS.2013.2294198
  15. X. N. Lu, J. M. Guerrero, K. Sun, and J. C. Vasquez, "An improved droop control method for DC microgrids based on low bandwidth communication with DC bus voltage restoration and enhanced current sharing accuracy," IEEE Trans. Power Electron., Vol. 29, No. 4, pp.1800-1812, Apr. 2014. https://doi.org/10.1109/TPEL.2013.2266419
  16. Y. Q. Liu, J. Z. Wang, N. N. Li, Y. Fu, and Y. C. Ji, "Enhanced load power sharing accuracy in droop-controlled DC microgrids with both mesh and radial configurations," Energies, Vol. 8, No. 5, pp. 3591-3605, Apr. 2015. https://doi.org/10.3390/en8053591
  17. J. Beerten, S. Cole, and R. Belmans, "Modeling of multi-terminal VSC HVDC systems with distributed DC voltage control," IEEE Trans. Power Syst., Vol. 29, No.1, pp.34-42, Jan. 2014. https://doi.org/10.1109/TPWRS.2013.2279268
  18. G. O. Kalcon, G. P. Adam, O. Anaya-Lara, S. Lo, and K. Uhlen, "Small-signal stability analysis of multi-terminal VSC-based DC transmission systems," IEEE Trans. Power Syst., Vol. 27, No. 4, pp. 1818-1830, Nov. 2012. https://doi.org/10.1109/TPWRS.2012.2190531
  19. R. T. Pinto, P. Bauer, S. F. Rodrigues, E. J. Wiggelinkhuizen, J. Pierik, and B. Ferreira, "A novel distributed direct-voltage control strategy for grid integration of off-shore wind energy systems through MTDC network," IEEE Trans. Ind. Electron., Vol. 60, No. 6, pp. 2429-2441, Jun. 2013. https://doi.org/10.1109/TIE.2012.2216239
  20. S. Lin and C. Yeh, "Microstrip branch-line coupler with optimized spurious suppression based on cascaded PI-type equivalent transmission lines," 2014 IEEE International Workshop on Electromagnetics, pp. 4-6, 2014.
  21. An Introduction to High Voltage Direct Current (HVDC) Underground Cable, Europacable, Brussels, 2011
  22. K. Rouzbehi, A. Miranian, J. I. Candela, A. Luna, and P. Rodriguez, "A generalized voltage droop strategy for control of multiterminal DC grids," IEEE Trans. Ind. Appl., Vol. 51, No. 1, pp. 607-618, Jan. 2015. https://doi.org/10.1109/TIA.2014.2332814
  23. A.-P. Monica, E.-A. Agusti, G.-A. Samuel, and G.-B. Oriol, "Droop control for loss minimization in HVDC multi-terminal transmission systems for large off-shore wind farms," Electric Power Systems Research, Vol. 112, No. 1, pp. 48-55, Apr. 2014. https://doi.org/10.1016/j.epsr.2014.03.013