DOI QR코드

DOI QR Code

Virtual Flux and Positive-Sequence Power Based Control of Grid-Interfaced Converters Against Unbalanced and Distorted Grid Conditions

  • Tao, Yukun (School of Electrical and Information Engineering, Zhengzhou University of Light Industry) ;
  • Tang, Wenhu (School of Electric Power Engineering, South China University of Technology)
  • Received : 2017.05.22
  • Accepted : 2018.01.26
  • Published : 2018.05.01

Abstract

This paper proposes a virtual flux (VF) and positive-sequence power based control strategy to improve the performance of grid-interfaced three-phase voltage source converters against unbalanced and distorted grid conditions. By using a second-order generalized integrator (SOGI) based VF observer, the proposed strategy achieves an AC voltage sensorless and grid frequency adaptive control. Aiming to realize a balanced sinusoidal line current operation, the fundamental positive-sequence component based instantaneous power is utilized as the control variable. Moreover, the fundamental negative-sequence VF feedforward and the harmonic attenuation ability of a sequence component generator are employed to further enhance the unbalance regulation ability and the harmonic tolerance of line currents, respectively. Finally, the proposed scheme is completed by combining the foregoing two elements with a predictive direct power control (PDPC). In order to verify the feasibility and validity of the proposed SOGI-VFPDPC, the scenarios of unbalanced voltage dip, higher harmonic distortion and grid frequency deviation are investigated in simulation and experimental studies. The corresponding results demonstrate that the proposed strategy ensures a balanced sinusoidal line current operation with excellent steady-state and transient behaviors under general grid conditions.

Acknowledgement

Supported by : Zhengzhou University of Light Industry

References

  1. Y. Suh, Y. G, and D. Rho, "A comparative study on control algorithm for active front-end rectifier of large motor drives under unbalanced input," IEEE Trans. Ind. Applicat., vol. 47, no. 3, pp. 1419-1431, May/Jun.2011. https://doi.org/10.1109/TIA.2011.2126015
  2. F. Blaabjerg, Z. Chen, and S. B. Kjaer, "Power electronics as efficient interface in dispersed power generation systems," IEEE Trans. Power Electron., vol. 19, no. 5, pp. 1184-1194, Sep. 2004. https://doi.org/10.1109/TPEL.2004.833453
  3. B. A. Welchko, T. A. Lipo, T. M. Jahns, and S. E. Schulz, "Fault tolerant three-phase AC motor drive topologies: A comparision of features, cost, and limitations," IEEE Trans. Power Electron., vol. 19, no. 4, pp. 1108-1116, Jul. 2004 https://doi.org/10.1109/TPEL.2004.830074
  4. Standard for interconnecting distributed resources with electric power systems, IEEE Std. 1547-2003, Sep. 2010.
  5. A. Timbus, M. Liserre, R. Teodorescu, P. Rodriguez, and F. Blaabjerg, "Evaluation of current controllers for distributed power generation systems," IEEE Trans. Power Electron., vol. 24, no. 3, pp. 654-664, Mar. 2009. https://doi.org/10.1109/TPEL.2009.2012527
  6. T. Noguchi, H. Tomiki, S. Kondo, and I. Takahashi, "Direct power control of PWM converter without power-source voltage sensors," IEEE Trans. Ind. Applicat., vol. 34, no. 3, pp. 473-479, May/Jun. 1998. https://doi.org/10.1109/28.673716
  7. A. Bouaa, J. P. Gaubert, and F. Krim, "Predictive direct power control of three-phase pulsewidth modulation (PWM) rectier using space-vector modulation (SVM)," IEEE Trans. Power Electron., vol. 25, no. 1, pp. 228-236, Jan. 2010. https://doi.org/10.1109/TPEL.2009.2028731
  8. P. Cortes, J. Rodriguez, P. Antoniewicz, and M. Kazmierkowski, "Direct power control of an AFE using predictive control," IEEE Trans. Power Electron., vol. 23, no. 5, pp. 2516-2523, Sep. 2008. https://doi.org/10.1109/TPEL.2008.2002065
  9. M. Malinowski, M. Jasinski, and M. P. Kazmierkowski, "Simple direct power control of three-phase PWM rectifier using space-vector modulation (DPC-SVM)," IEEE Trans. Ind. Electron., vol. 51, no. 2, pp. 447-454, Apr. 2004. https://doi.org/10.1109/TIE.2004.825278
  10. K. Ma, W. Chen, M. Liserre, and F. Blaabjerg, "Power controllability of a three-phase converter with an unbalanced AC source," IEEE Trans. Power Electron., vol. 30, no. 3, pp. 1591-1604, Mar. 2015. https://doi.org/10.1109/TPEL.2014.2314416
  11. L. Shang and J. Hu, "Sliding-mode-based direct power control of grid-connected wind-turbine-driven doubly fed induction generators under unbalanced grid voltage conditions," IEEE Trans. Energy Convers., vol. 27, no. 2, pp. 362-373, Jun. 2012. https://doi.org/10.1109/TEC.2011.2180389
  12. J. Hu and Z. Q. Zhu, "Investigation on switching patterns of direct power control strategies for gridconnected DC-AC converters based on power variation rates," IEEE Trans. Power Electron., vol. 26, no. 12, pp. 3582-3598, Dec. 2011. https://doi.org/10.1109/TPEL.2011.2164812
  13. M. Malinowski, G. Marques, M. Cichowlas, and M. P. Kazmierkowski, "New direct power control of three-phase pwm boost rectifiers under distorted and imbalanced line voltage conditions," in Proc. IEEE ISIE, vol. 1, Jun. 2003, pp. 438-443.
  14. M. P. Kazmierkowski, M. Jasinski, and G. Wrona, "DSP-based control of grid-connected power converters operating under grid distortions," IEEE Trans. Ind. Electron., vol. 7, no. 2, pp. 204-211, May 2011.
  15. P. R. Martinez-Rodriguez, G. Escobar, A. A. Valdez-Fernandez, M. Hernandez-Gomez, and J. M. SosaE, "Direct power control of a three-phase rectifier based on positive sequence detection," IEEE Trans. Ind. Electron., vol. 61, no. 8, pp. 4084-4092, Aug. 2014. https://doi.org/10.1109/TIE.2013.2286560
  16. J. A. Suul and T. Undeland, "Impact of virtual flux reference frame orientation on voltage source inverters in weak grids," in Proc. IPEC, Sapporo, Jun. 2010, pp. 468-375.
  17. N. R. N. Idris and A. H. M. Yatim, "An improved stator flux estimation in steady-state operation for direct torque control of induction machines," IEEE Trans. Ind. Appl., vol. 38, no. 1, pp. 110-116, Jan./Feb. 2002. https://doi.org/10.1109/28.980364
  18. A. Kulka, "Sensorless digital control of grid connected three phase converters for renewable sources," Ph.D. dissertation, Norwegian Univ. Sci. Technol., Trondheim, Norway, 2009.
  19. J. A. Suul, A. Luna, P.Rodriguez, and T. Undeland, "Voltage-sensor-less synchronization to unbalanced grids by frequency-adaptive virtual flux estimation," IEEE Trans. Ind. Electron., vol. 59, no. 7, pp. 2910-2923, Jul. 2012. https://doi.org/10.1109/TIE.2011.2168793
  20. H. Akagi, E.Watanabe, and M.Aredes, Instantaneous Power Theory and Applications to Power Conditioning. New York: Wiley, 2007.
  21. Y. K. Tao, Q. H. Wu, L. Wang, and W. H. Tang, "Voltage sensorless predictive direct power control of three-phase PWM converters," IET Power Electron., vol. 9, no. 5, pp. 1009-1018, Apr. 2016. https://doi.org/10.1049/iet-pel.2014.0713