Energized Diagnostic Technology of Cable Cross-Bonded Defects

A new type of energized diagnostic technique aimed at defects in the cross-bonded grounding system of power cables is proposed. Based on the equivalent model of a normal cross-bonded grounding unit, the equivalent models of 23 common cross-bonded defects were analyzed in depth, and a general matrix calculation model was summarized to provide the possibility of programming calculations. The programs were then written in Java for both a normal cross-bonded grounding unit and defective cross-bonded grounding units to form a software that can realize an energized diagnosis of defects in the cross-bonded grounding system of the transmission cable system. The software was applied to a 220 kV cable line with some defects in its cross-bonded grounding system for energized diagnosis, and the diagnostic result was consistent with the actual defect. It took only half an hour to remove the defects after the power failure. It was proven that the software can accurately diagnose defects in cross-bonded grounding system with shorter outage time and higher power supply reliability.