A STUDY ON ZERO SEQUENCE DC SMALL CURRENT EARTHING LINE SELECTION SYSTEM LEAKING RESISTANCE DC VOLTAGE

摘要

This paper offers a theoretical analysis of natural DC voltage applied by zero sequence DC small current line selection system on power grid leaking resistance, which gives mathematical model and experiment curve to reveal the rule of increase of leaking resistance voltage with leaking resistance, so that detection current circuit can also be formed when HV dual screened cable intermittent electric leakage leaves low resistance status. This provides a new solution for the difficulty in detecting non-complete damage of HV cable by the traditional method to apply LV additional detection voltage.