Characterization and Fault Analysis of Single-Core Cable Sheath Circulation Based on ATP-EMTP

Since all major high-voltage cable projects currently use cable metal sheath grounding as an important safety protection measure, it is inevitable that sheath circulation will be generated in the cable, resulting in increased temperature rise of the cable metal sheath, reduced load capacity, accelerated insulation aging and other adverse effects. Therefore, based on the ATP-EMTP software, this paper establishes the sheath circulation model of the cable and analyzes the sheath circulation characteristics of the cable by selecting physical quantities such as cable ampacity and phase spacing, and proposes a method to suppress the cable sheath circulation. Meanwhile, a model of cable insulation ground fault is built in ATP-EMTP, and a preliminary method to determine the type and distance of insulation fault is proposed using sheath circulating current.