Methodology of Detection for Power Cable Insulation Defects Based on DC Voltage Withstand Test

摘要

The DC voltage withstand test of power cable can find some insulation defects. It is a crucial test to ensure the safe operation of cable. This chapter puts forward the methodology of detection for power cable insulation defects based on DC voltage withstand test. This methodology regards the transient voltage and current in each stage of voltage rising as the signal source, and it is based on the discriminant function which relies on voltage and current. Then, the methodology can diagnose the existence of insulation defects (including the seriousness) for the power cable. For cable that has undergone DC voltage withstand test, this methodology can diagnose the existence of insulation damage. The simulation calculation preliminarily verifies the feasibility and effectiveness of the methodology in this chapter. The proposed detecting methodology cannot be applied to all the discriminant items of AC voltage withstand test, but it can make full use of the information provided by voltage withstand tests to improve sensitivity and efficiency of the detection and diagnosis methodology and assist the insulation supervision and safety operation of power cable.