Leakage Currents Separation of Cross-bonded Cables Based on Sheath Current Vector Difference

The leakage currents detection is an effective method to evaluate the insulation condition of power cable. However, one of the significant challenges of the leakage currents detection is the leakage currents separation, because the leakage currents are mixed with the sheath circulating currents. Therefore, the leakage currents separation method of cross-bonded cable system based on sheath current vector difference was proposed and verified in the paper. Firstly, a separation method of differentiating the leakage currents and sheath circulating currents in the cross-bonded cable system with three imports of cross-bonded link box was proposed. Then, the simulation model of 110kV cross-linked polyethylene (XLPE)cable was established by PSCAD software. Furthermore, the separation method was used in cross-bonded cable simulation system. Finally, an actual on-site leakage currents testing of single-end-grounded cable system was carried. Simulation results indicated the proposed separation method can be accessible to differentiate the leakage current individually in the cross-bonded cable system with three imports of cross-bonded link box. The proposed simulation model can be applied to calculate the actual leakage currents in the single-end-grounded cable system.