Title :
Application of wavelet-based de-noising to online measurement of partial discharges
Author :
Wang, P. ; Lewin, P.L. ; Tian, Y. ; Sutton, S.J. ; Swingler, S.G.
Author_Institution :
Sch. of Electron. & Comput. Sci., Southampton Univ., UK
Abstract :
For online detection of partial discharge (PD) activity within power cables and cable accessories, one of the non-conventional PD detection techniques, VHF capacitive coupling has been proved to be suitable. However, the existence of excessive interference can significantly influence the measurement sensitivity and reliability. This paper investigates the application of wavelet transforms for de-noising signals obtained using capacitive couplers. The experimental work has been carried out on a 132 kV cable loop with a known defect within the cable joint. Obtained results indicate that the wavelet analysis technique can effectively discriminate internal PD pulses among corona discharges and pulse-like interference. Further, removal of interference has been achieved by applying level dependent threshold values.
Keywords :
cable jointing; corona; electric connectors; interference (signal); partial discharge measurement; power cables; signal denoising; signal detection; wavelet transforms; 132 kV; VHF capacitive coupling; cable accessories; cable joint; cable loop; capacitive couplers; corona discharges; internal PD pulses; level dependent threshold voltage; measurement reliability; measurement sensitivity; nonconventional PD detection process; online PD measurement; online partial discharge measurement; power cables; pulse like interference; wavelet analysis method; wavelet transform based denoising signals; Continuous wavelet transforms; Couplers; Discrete wavelet transforms; Filters; Frequency; Interference; Noise reduction; Partial discharges; Power cables; Wavelet analysis;
Conference_Titel :
Solid Dielectrics, 2004. ICSD 2004. Proceedings of the 2004 IEEE International Conference on
Print_ISBN :
0-7803-8348-6
DOI :
10.1109/ICSD.2004.1350507
