Accurate Voltage Parameter Estimation for Grid Synchronization in Single-Phase Power Systems

Dai, Zhiyong;Lin, Hui;Tian, Yanjun;Yao, Wenli;Yin, Hang

  • 투고 : 2015.03.06
  • 심사 : 2015.12.28
  • 발행 : 2016.05.20


This paper presents an adaptive observer-based approach to estimate voltage parameters, including frequency, amplitude, and phase angle, for single-phase power systems. In contrast to most existing estimation methods of grid voltage parameters, in this study, grid voltage is treated as a dynamic system related to an unknown grid frequency. Based on adaptive observer theory, a full-order adaptive observer is proposed to estimate voltage parameters. A Lyapunov function-based argument is employed to ensure that the proposed estimation method of voltage parameters has zero steady-state error, even when frequency varies or phase angle jumps significantly. Meanwhile, a reduced-order adaptive observer is designed as the simplified version of the proposed full-order observer. Compared with the frequency-adaptive virtual flux estimation, the proposed adaptive observers exhibit better dynamic response to track the actual grid voltage frequency, amplitude, and phase angle. Simulations and experiments have been conducted to validate the effectiveness of the proposed observers.


Adaptive observer;Grid synchronization;Voltage parameter estimation;Zero steady-state estimation error


  1. M. S. Reza, M. Ciobotaru, and V. G. Agelidis, “Accurate estimation of single-phase grid voltage parameters under distorted conditions,” IEEE Trans. Power Del., Vol. 29, No. 3, pp. 1138-1146, Jun. 2014.
  2. E. Jacobsen and R. Lyons, “The sliding dft,” IEEE Signal Process. Mag., Vol. 20, No. 2, pp. 74-80, Mar. 2003.
  3. A. A. Girgis and F. M. Ham, “A quantitative study of pitfalls in the fft,” IEEE Trans. Aerosp. Electron. Syst., Vol. AES-16, No. 4, pp. 434-439, Jul. 1980.
  4. A. Routray, A. K. Pradhan, and K. P. Rao, “A novel kalman filter for frequency estimation of distorted signals in power systems,” IEEE Trans. Instrum. Meas., Vol. 51, No. 3, pp. 469-479, Jun. 2002.
  5. O. Vainio and S. J. Ovaska, “Noise reduction in zero crossing detection by predictive digital filtering,” IEEE Trans. Ind. Electron., Vol. 42, No. 1, pp. 58-62, Feb. 1995.
  6. O. Vainio, S. J. Ovaska, and M. Polla, “Adaptive filtering using multiplicative general parameters for zero-crossing detection,” IEEE Trans. Ind. Electron., Vol. 50, No. 6, pp. 1340-1342, Dec. 2003.
  7. H.-S. Song, K. Nam, and P. Mutschler, "Very fast phase angle estimation algorithm for a single-phase system having sudden phase angle jumps," in 37th Annual Meeting, Industry Applications conference(IAS), Vol. 2, pp. 925-931, 2002.
  8. L. L. Lai, W. L. Chan, C. T. Tse, and A. T. P. So, “Real-time frequency and harmonic evaluation using artificial neural networks,” IEEE Trans. Power Del., Vol. 14, No. 1, pp. 52-59, Jan. 1999.
  9. Z. Y. Dai, W. Lin, and H. Lin, “Estimation of single-phase grid voltage parameters with zero steady-state error,” IEEE Trans. Power Electron., Vol. 31, No. 5, pp. 3867-3879, Jul. 2015.
  10. D. Yazdani, A. Bakhshai, G. Joos, and M. Mojiri, “A nonlinear adaptive synchronization techniquefor grid connected distributed energy sources,” IEEE Trans. Power Electron., Vol. 23, No. 4, pp. 2181-2186, Jul. 2008.
  11. M. Mojiri and A. R. Bakhshai, “Estimation of frequencies using adaptive notch filter,” IEEE Trans. Circuits Syst. II, Exp. Briefs, Vol. 54, No. 4, pp. 338-342, Apr. 2007.
  12. K.-J. Lee, J.-P. Lee, D. Shin, D.-W. Yoo, and H.-J. Kim, “A novel grid synchronization pll method based on adaptive lowpass notch filter for grid-connected pcs,” IEEE Trans. Ind. Electron., Vol. 61, No. 1, pp. 292-301, Jan. 2014.
  13. G. Yin, L. Guo, and X. Li, “An amplitude adaptive notch filter for grid signal processing,” IEEE Trans. Power Electron., Vol. 28, No. 6, pp. 2638-2641, Jun. 2013.
  14. W. Li, X. Ruan, X. Wang, and D. Pan, “Grid synchronization systems of three-phase grid-connected power converters: a complex-vector-filter perspective,” IEEE Trans. Ind. Electron., Vol. 61, No. 4, pp. 1855-1870, Apr. 2014.
  15. S. Golestan, M. Monfared, F. D. Freijedo, and J. M. Guerrero, “Performance improvement of a pre-filtered synchronous-referenceframe pll by using a pid-type loop filter,” IEEE Trans. Ind. Electron., Vol. 61, No. 7, pp. 3469-3479, Jul. 2014.
  16. S. Golestan, M. Monfared, F. D. Freijedo, and J. M. Guerrero, “Dynamics assessment of advanced single-phase pll structures,” IEEE Trans. Ind. Electron., Vol. 60, No. 6, pp. 2167-2177, Jun. 2013.
  17. R. Zhang, M. Cardinal, P. Szczesny, and M. Dame, "A grid simulator with control of single-phase power converters in dq rotating frame," in IEEE 33rd Annual Power Electronics Specialists Conference(PESC), Vol. 3, pp. 1431-1436, 2002.
  18. R. Teodorescu, M. Liserre, and P. Rodriguez, Grid Converters for Photovoltaic and Wind Power Systems, John Wiley & Sons, Chap. 4, 2011.
  19. M. Saitou and T. Shimizu, "Generalized theory of instantaneous active and reactive powers in single-phase circuits based on hilbert transform," in IEEE 33rd Annual Power Electronics Specialists Conference(PESC), Vol. 3, pp. 1419-1424, 2002.
  20. M. Ciobotaru, R. Teodorescu, and F. Blaabjerg, "A new singlephase pll structure based on second order generalized integrator," in 37th IEEE Power Electronics Specialists Conference(PESC), pp. 1-6, 2006.
  21. J. A. Suul, A. Luna, P. Rodriguez, and T. Undeland, "Frequency-adaptive virtual flux estimation for grid synchronization under unbalanced conditions," in 36th Annual Conference on IEEE Industrial Electronics Society (IECON), pp. 486-492, Nov. 2010.
  22. A. Luna, C. Citro, C. Gavriluta, J. Hermoso, I. Candela, and P. Rodriguez, "Advanced PLL structures for grid synchronization in distributed generation," in International Conference on Renewable Energies and Power Quality (ICREPQ), pp. 2769-2776, Mar. 2012.
  23. H. K. Khalil and J. Grizzle, Nonlinear systems, Prentice Hall, Upper Saddle River, Chap. 4, 2002
  24. W. J. Rugh, Linear system theory, 2th edition, Prentice Hall, Upper Saddle River, Chap. 4, 1996.