Title :
Diagnostic of water trees using DC and AC voltages
Author :
Romero, Pedro ; Puerta, Julio
Author_Institution :
INTEVEP SA, Caracas, Venezuela
Abstract :
Electric tools for nondestructive water tree diagnostics in XLPE medium voltage power cables, by means of DC and AC voltages, are presented. The DC method is related to the determination of a nonlinear dependence of the polarization current on the applied DC step voltage, in contrast to a linear dependence found in nonwater tree-damaged cables. In both cases, the current follows the Curie-von Schweidler empirical law. The AC method is based on the measurement of the dispersion relation of both the loss factor and the capacitance in the low and very low frequency ranges by means of Fourier transform techniques. The devised measuring instrumentation is also presented
Keywords :
XLPE insulation; electric breakdown; insulation testing; nondestructive testing; power cable insulation; power cable testing; trees (electrical); AC method; Curie-von Schweidler empirical law; DC method; Fourier transform techniques; XLPE MV power cables; applied DC step voltage; capacitance; dispersion relation; loss factor; measuring instrumentation; nondestructive water tree diagnostics; polarization current; Capacitance measurement; Dispersion; Fourier transforms; Frequency measurement; Instruments; Loss measurement; Medium voltage; Polarization; Power cables; Trees - insulation;
Conference_Titel :
Electrical Insulation, 1996., Conference Record of the 1996 IEEE International Symposium on
Conference_Location :
Montreal, Que.
Print_ISBN :
0-7803-3531-7
DOI :
10.1109/ELINSL.1996.549307
