Study on Voltage Sag Detection of Wind Power System Based on HHT
- 1 Hebei Provincial Key Laboratory of Power Transmission Equipment Security Defense, North China Electric Power University, Baoding, China
- 2 Hebei Provincial Key Laboratory of Power Transmission Equipment Security Defense, North China Electric Power University, Baoding, China
- 3 Hebei Provincial Key Laboratory of Power Transmission Equipment Security Defense, North China Electric Power University, Baoding, China
- 4 Hebei Provincial Key Laboratory of Power Transmission Equipment Security Defense, North China Electric Power University, Baoding, China
Abstract
For the output of wind power system has the characteristics of randomness, volatility and intermittence, the voltage of wind power system fluctuates frequently and voltage sag is one of the most common voltage fluctuations in wind power system. For the problem of voltage sag of wind power system, the limitations of the detection methods such as the square detection method, the half-wave RMS detection method and wavelet transform are summed up, and a new detecting method named Hilbert-huang Transform(HHT) is put forward in this paper, which can detect the voltage sag accurately and timely. In order to solve the problem of end effect in the process of empirical mode decompostion (EMD) , a self-adaptive method named improved waveform matching is applied in dealing with the end issue. Voltage fluctuations are reflected by two parameters named voltage amplitude and frequency of each intrinsic mode function (IMF) in HHT. The practicality of the method is verified by Matlab simulation.
- Y. Zhang and G. D. Gao, “Wind power generation,” Beijing, China Power Press, 2002.
- Y. Y. Hu, S. S. Niu, Z. R. Liang, etc. “Of Voltage Flicker Measurement Algorithm,” Journal of Low Voltage Electrical Appliances, 2012, pp. 32-36.
- S. J. Hu, J. L. Li and M. L, “Test Method of Wind Power System’s Implementation LVRT Grid Voltage Drop. High Power Communication Technology, Vol. 2, 2008, pp. 17-21.
- X. P. Wei, Y. H. Xu and X. G. Xiao, “Voltage Fluctuation and Flicker Detection Methods in Electric Measurement and Instrument., Vol. 46, 2009, pp. 1-6.
- Y. C. Liu, “Analysis and Study of Voltage Sag’s Detection Method,” Changsha: hunan university, 2007.
- T. Y. Li, Y. Zhao, N. Li N, etc. “New Method for the Detection of Power Quality Based on the HHT,” Chinese Journal of Electrical Engineering, Vol. 17, 2005, pp. 32-56.
- Y. M. Zhong, S. R. Qin and B. P. Shang, “Research of Hilbert - Huang Transform,” Journal of Vibration and Impact, Vol. 21. 2002, pp. 13-17.
- D. J. Yu, J. S. Cheng, Y. Yang and H. Hilbert, “Transform Method for Mechanical Fault Diagnosis,” Beijing: Science Press, 2006.
- C. X. Shao, J. Wang, J. F. Fan, etc., “An adaptive EMD endpoint continuation method,” Journal of Electronics, Vol. 35, 2007, pp. 1944-1947.