Research On The Detection Methodology Of Cable Insulation Defects

Power cables for its good electrical insulating performance and mechanical properties are widely used in power transmission and distribution network of cities, but in the power cable of the production, transport, installation and operation process will inevitably produce all sorts of defects, thus become the safe operation of the power system hidden trouble. The cable insulation defects diagnosis, could help identify the defects, sure insulation status, to improve the power system operation reliability is of great significance.This paper presents a new method of insulation defects detection for power cable based on oscillating wave voltage. This method takes the same kind of power cable statistical data or setting for reference database data, oscillating wave voltage measurement for the voltage and current source (source), Structure of power cable insulation fault discriminant function f (u, i, t), generating discriminant function extreme of the sequence, according to a maximum of discriminant function, cable insulation fault detection and fault diagnosis. Criterion function f (u, i, t) is, in fact, a kind of nonlinear mapping, and it directly the difference of defects are given, not in the strong noise background extraction a tiny characteristic features, thus has the strong anti-interference ability. The proposed method makes full use of the valuable information provided by oscillating wave voltage test, thus improves the efficiency of oscillating wave voltage test of power cable and is of benefit to the development of power cable detection technology.In this paper based on the oscillations of the voltage of power cable insulation fault detection methods can make full use of power cable oscillating wave test provide valuable information, improing the power cable oscillating wave test efficiency, helping power cable test technology development.