High frequency components of feeder current as diagnostic tool to study contamination conditions of outdoor insulators in power distribution networks

The aperiodic occurrence of widespread contamination related outages is a problem that distribution utilities are faced. These faults sometimes suddenly and seriously damage the system and reduce power quality and power system reliability. Usually insulator washing is a solution for this problem and its events. Since insulator washing has a high cost, it should be done by a primary and organized planning, although the contamination level is reduced naturally by heavy precipitation and fault probability is declined. One of the solutions of washing planning is studying of feeder insulators leakage current (ILC). This paper presents a new method for studying the insulators contamination(IC) level using Discrete Wavelet Transform (DWT) and Principal Component Analysis (PCA). The proposed method has been examined in a 45 days period and an index for contamination level has been extracted. Finally the algorithm of proposed method has been presented. Experimental results demonstrate that the high-frequency components can be used effectively to study the contamination conditions of outdoor insulators.

[1]  C. N. Richards,et al.  Development of a remote insulator contamination monitoring system , 1997 .

[2]  O. P. Malik,et al.  Development of a fuzzy inference system based on genetic algorithm for high-impedance fault detection , 2006 .

[3]  T. Oyamada,et al.  Spectral analysis of leakage current on contaminated insulators by auto regressive method , 1998, 1998 Annual Report Conference on Electrical Insulation and Dielectric Phenomena (Cat. No.98CH36257).

[4]  R. I. Diego,et al.  Application of the wavelet-packet transform to the estimation of harmonic groups in current and voltage waveforms , 2006, IEEE Transactions on Power Delivery.

[5]  J. Simonoff.  Smoothing Methods in Statistics , 1998 .

[6]  Thierry Blu,et al.  Wavelet theory demystified , 2003, IEEE Trans. Signal Process..

[7]  N. Yoshimura,et al.  Leakage current characterization for estimating the conditions of ceramic and polymeric insulating surfaces , 2004, IEEE Transactions on Dielectrics and Electrical Insulation.

[8]  Xie Li-li.  New Method for Leakage Current Detection of Insulators Based on Wavelet Transform , 2005 .

[9]  F. Amarh.  Electric transmission line flashover prediction system , 2001 .

[10]  Ronnie Belmans,et al.  Wavelet-based power quantification approaches , 2002, IMTC/2002. Proceedings of the 19th IEEE Instrumentation and Measurement Technology Conference (IEEE Cat. No.00CH37276).

[11]  Mohammad Javad Dehghani.  Comparison of S-transform and Wavelet Transform in Power Quality Analysis , 2009 .

[12]  G. F. Burani,et al.  Leakage current monitoring of insulators exposed to marine and industrial pollution , 1996, Conference Record of the 1996 IEEE International Symposium on Electrical Insulation.

[13]  T. Croes,et al.  Power measurement using the wavelet transform of analytic signals , 2004, 2004 11th International Conference on Harmonics and Quality of Power (IEEE Cat. No.04EX951).

[14]  Y.-C. Song,et al.  High-frequency components of leakage current as diagnostic tool to study aging of polymer insulators under salt fog , 2005 .