Continuous on-line monitoring of partial discharges in high voltage cables

This work reviews data acquisition, transmission and processing methodologies for continuous on-line monitoring of partial discharges in power cable systems. A PD continuous online monitoring system for underground cable circuits using capacitive couplers, LiNbO/sub 3/ electro-optic modulators, laser, optical switch and optical fibers has been proposed. Data processing methods include pulse shape and spectrum analysis, time of flight analysis, phase-resolved two-dimensional histograms, three-dimensional /spl phi/-q-n patterns, trend analysis, wavelet-based denoising, alarm strategy and telecommunication function to enable remote control and data download.