Journal of Power Electronics

The Korean Institute of Power Electronics (전력전자학회)
권호 표지
DOI QR코드

DOI QR Code

BPF-based Grid Voltage Feedforward Control of Grid-connected Converters for Improving Robust Stability

  • Yang, Shude (School of Automation and Information Engineering, Xi'an University of Technology) ;
  • Tong, Xiangqian (School of Automation and Information Engineering, Xi'an University of Technology) ;
  • Yin, Jun (School of Automation and Information Engineering, Xi'an University of Technology) ;
  • Wang, Haiyan (School of Automation and Information Engineering, Xi'an University of Technology) ;
  • Deng, Yaping (School of Automation and Information Engineering, Xi'an University of Technology) ;
  • Liu, Le (School of Automation and Information Engineering, Xi'an University of Technology)
  • Received : 2016.07.31
  • Accepted : 2017.01.20
  • Published : 2017.03.20
Download PDF
⟨ Previous Next ⟩

Abstract

Grid voltage feedforward is extensively used for controlling grid-connected converters. However, the conventional voltage feedforward control reduces the stability margins of the converter connected to a high-impedance grid. The effect mechanism of voltage feedforward on the grid-connected converter control under high-inductive conditions of the grid impedance is clearly explained in this study using the equivalent transformations of control block diagrams. Results show that the delay produced by the digital control is the root cause of this effect. An improved voltage feedforward strategy, in which a bandpass filter (BPF) is introduced into the feedforward path, is proposed to strengthen the converter's robust stability against grid impedance variations. The selection method of the BPF's bandwidth is also provided considering the tradeoff between the response speed to the grid voltage sag and the system's robust stability. The converter can work stably over a wide range of the grid impedance through the proposed approach. Simulation and experimental results fully verify the effectiveness of the BPF-based voltage feedforward strategy.

Keywords

References

  1. A. Alexander and M. Thathan, "Modelling and analysis of modular multilevel converter for solar photovoltaic applications to improve power quality," IET Renew. Power Gener., Vol. 9, No. 1, pp. 78-88, Jan. 2015. https://doi.org/10.1049/iet-rpg.2013.0365
  2. M. Zabaleta, E. Burguete, D. Madariaga, I. Zubimendi, M. Zubiaga, and I. Larrazabal, "LCL grid filter design of a multimegawatt medium-voltage converter for offshore wind turbine using SHEPWM modulation," IEEE Trans. Power Electron., Vol. 31, No. 3, pp. 1993-2001, Mar. 2016. https://doi.org/10.1109/TPEL.2015.2442434
  3. K. Yang, Y. Wang, and G. Chen, "Design and research on high-reliability HPEBB used in cascaded DSTATCOM," Journal of Power Electronics, Vol. 15, No. 3, pp. 830-840, May. 2015. https://doi.org/10.6113/JPE.2015.15.3.830
  4. P. Garanayak, and G. Panda, "Harmonic elimination and reactive power compensation with a novel control algorithm based active power filter," Journal of Power Electronics, Vol. 15, No. 6, pp.1619-1627, Nov. 2015. https://doi.org/10.6113/JPE.2015.15.6.1619
  5. M. Liserre, R. Teodorescu, and F. Blaabjerg, "Stability of photovoltaic and wind turbine grid-connected inverters for a large set of grid impedance values," IEEE Trans. Power Electron., Vol. 21, No. 1, pp. 263-272, Jan. 2006. https://doi.org/10.1109/TPEL.2005.861185
  6. E. M. Lightner, and S. E. Widergren, "An orderly transition to a transformed electricity systems," IEEE Trans. Smart Grid., Vol. 1, No. 1, pp. 3-10, Jun. 2010. https://doi.org/10.1109/TSG.2010.2045013
  7. J. Sun, "Impedance-based stability criterion for grid-connected inverters," IEEE Trans. Power Electron., Vol. 26, No. 11, pp. 3075-3078, Nov. 2011. https://doi.org/10.1109/TPEL.2011.2136439
  8. IEEE standard for interconnecting distributed resources with electric power systems, IEEE Std 1547-2003, 2003.
  9. Technical rule for photovoltaic power station connected to power grid, Q/GDW617-2011, 2011.
  10. Y. Han, P. Shen, and J. M. Guerrero, "Stationary frame current control evaluations for three-phase grid-connected inverters with PVR-based active damped LCL filters," Journal of Power Electronics, Vol. 16, No. 1, pp. 297-309, Jan. 2016. https://doi.org/10.6113/JPE.2016.16.1.297
  11. W. Wu, Y. He, and F. Blaabjerg, "An LLCL power filter for single-phase grid-tied inverter," IEEE Trans. Power Electron., Vol. 27, No. 2, pp. 782-789, Feb. 2012. https://doi.org/10.1109/TPEL.2011.2161337
  12. J. Xu, J. Yang, J. Ye, Z. Zhang, and A. Shen, "An LTCL filter for three-phase grid-connected converters," IEEE Trans. Power Electron., Vol. 29, No. 8, pp. 4322-4338, Aug. 2014. https://doi.org/10.1109/TPEL.2013.2292000
  13. J. L. Agorreta, M. Borrega, J. Lopez, and L. Marroyo, "Modeling and control of N-paralleled grid-connected inverters with LCL filter coupled due to grid impedance in PV plants," IEEE Trans. Power Electron., Vol. 26, No. 3, pp. 770-785, Mar. 2011. https://doi.org/10.1109/TPEL.2010.2095429
  14. J.J Sun, W. Hu, H. Zhou, Y.M. Jiang, and X.M. Zha, "A resonant characteristics analysis and suppression strategy for multiple parallel grid-connected inverters with LCL filter," Journal of Power Electronics, Vol. 16, No. 4, pp. 1483-1493, Jul. 2016. https://doi.org/10.6113/JPE.2016.16.4.1483
  15. M. Liserre, F. Blaabjerg, and R. Teodorescu, "Grid impedance estimation via excitation of LCL-filter resonance," IEEE Trans. Ind. Appl., Vol. 43, No. 5, pp. 1401-1407, Sep. 2007. https://doi.org/10.1109/TIA.2007.904439
  16. P. Alemi, S. Y. Jeong, and D.-C. Lee, "Active damping of LLCL filters using PR control for grid-connected three-level T-type converters," Journal of Power Electronics, Vol. 15, No. 3, pp. 786-795, May. 2015. https://doi.org/10.6113/JPE.2015.15.3.786
  17. X. Zhou, J. Fan, and A. Q. Huang, "High-frequency resonance mitigation for plug-in hybrid electric vehicles' integration with a wide range of grid conditions," IEEE Trans. Power Electron., Vol. 27, No. 11, pp. 4459-4471, Nov. 2012. https://doi.org/10.1109/TPEL.2012.2185833
  18. Z. Wan, J. Xiong, J. Lei, C. Chen, and K. Zhang, "A modified capacitor current feedback active damping approach for grid connected converters with an LCL filter," Journal of Power Electronics, Vol. 15, No. 5, pp. 1286-1294, Sep. 2015. https://doi.org/10.6113/JPE.2015.15.5.1286
  19. D. Pan, X. Ruan, C. Bao, W. Li, and X. Wang, "Optimized controller design for LCL-type grid-connected inverter to achieve high robustness against grid-impedance variation," IEEE Trans. Power Electron., Vol. 62, No. 3, pp. 1537-1547, Mar. 2015. https://doi.org/10.1109/TED.2015.2409478
  20. X. Wang, F. Blaabjerg, M. Liserre, Z. Chen, J. He, and Y. Li, "An active damper for stabilizing power-electronics-based AC systems," IEEE Trans. Power Electron., Vol. 29, No. 7, pp. 3318-3329, Jul. 2014. https://doi.org/10.1109/TPEL.2013.2278716
  21. D. Dong, B. Wen, D. Boroyevich, P. Mattavelli, and Y. Xue, "Analysis of phase-locked loop low-frequency stability in three-phase grid-connected power converters considering impedance interactions," IEEE Trans. Ind. Electron., Vol. 62, No. 1, pp. 310-321, Jan. 2015. https://doi.org/10.1109/TIE.2014.2334665
  22. B. Wen, D. Boroyevich, R. Burgos, P. Mattavelli, and Z. Shen, "Analysis of D-Q small-signal impedance of grid-tied inverters," IEEE Trans. Power Electron., Vol. 31, No. 1, pp. 675-687, Jan. 2016. https://doi.org/10.1109/TPEL.2015.2398192
  23. J. Zhou, D. Hui, S. Fan, Y. Zhang, and A. M. Gole, "Impact of short-circuit ratio and phase-locked-loop parameters on the small-signal behavior of a VSC-HVDC converter," IEEE Trans. Power Del., Vol. 29, No. 5, pp. 2287-2296, Oct. 2014. https://doi.org/10.1109/TPWRD.2014.2330518
  24. L. Zhang, L. Harnefors, and H.-P. Nee, "Power-synchronization control of grid-connected voltage-source converters," IEEE Trans. Power Syst., Vol. 25, No. 2, pp. 809-820, May. 2010. https://doi.org/10.1109/TPWRS.2009.2032231
  25. L. Zhang, L. Harnefors, and H.-P. Nee, "Interconnection of two very weak ac systems by VSC-HVDC links using power-synchronization control," IEEE Trans. Power Syst., Vol. 26, No. 1, pp. 344-355, Feb. 2011. https://doi.org/10.1109/TPWRS.2010.2047875
  26. S. Zhou, X. Zou, D. Zhu, Y. Kang, L. Tong, and X.Gao, "LCL type grid-connected converter no startup inrush current control method based on capacitor branch voltage feedforward," in Industrial Electronics Society, IECON 2015-41st Annual Conference of the IEEE, pp. 1471-1476, Nov. 2015.
  27. J. Xu, S. Xie, and T. Tang, "Evaluations of current control in weak grid case for grid-connected LCL-filtered inverter," IET Power Electron., Vol. 6, No. 2, pp. 227-234, Feb. 2013. https://doi.org/10.1049/iet-pel.2012.0192
  28. J. Xu, S. Xie, and T. Tang, "Improved control strategy with grid-voltage feedforward for LCL-filter-based inverter connected to weak grid," IET Power Electron., Vol. 7, No. 10, pp. 2660-2671, Oct. 2014. https://doi.org/10.1049/iet-pel.2013.0666
  29. T.-F. Wu, K.-H. Sun, C.-L. Kuo, and C.-H. Chang, "Predictive current controlled 5-kW single-phase bidirectional inverter with wide inductance variation for DC-microgrid applications," IEEE Trans. Power Electron., Vol. 25, No. 12, pp. 3076-3084, Dec. 2010. https://doi.org/10.1109/TPEL.2010.2087773
  30. S. Jiang, D. Cao, Y. Li, and F.Z. Peng, "Grid-connected boost-half-bridge photovoltaic microinverter system using repetitive current control and maximum power point tracking," IEEE Trans. Power Electron., Vol. 27, No. 11, pp. 4711-4722, Nov. 2012. https://doi.org/10.1109/TPEL.2012.2183389
  31. R. W. Erickson and D. Maksimovic, Fundamentals of Power Electronics, 2nd ed. Norwell, MA: Kluwer, 2001 : 330-410.
  32. G. F. Franklin, D.J. Powell and A. E. Naeini, Feedback Control of Dynamic Systems, 6th ed., Addison-Wesley Professional, Chap. 6.7.6, 2009.