Research on "two-step positioning method" of high voltage cross-bonded cable based on sheath current

After the cable failure, whether the fault location can be carried out immediately has an effect on the power supply reliability of the urban power grid. Different from overhead lines, the cable has multi-layer metal structure, especially the high-voltage cross-bonded cable, which makes the electrical relationship between the layers complex. It is very difficult for the traditional transmission line theory and fault location method to accurately locate the fault. In this paper, based on the analysis of the structure of high voltage cross-bonded cable, the model of sheath current is established, and the single-phase fault criterion and location method based on sheath current are summarized. Through a large number of simulations, it is verified that the proposed algorithm is still applicable to different fault types, fault locations, transition resistances and fault initial phase angles, and has high ranging accuracy.