The Study Of The Measurement Of The Zero-Sequence Current For High-Resistance Grounded Distribution System

Based on an overview of the merits and drawbacks of all the neutral groundingmodes and the research status of the single-phase-to-ground fault feeder detectionmethods in 10kV power distribution network, the present paper highlights thesuperiorities in adopting the high-resistance grounding mode and zero-sequencesingle-phase-to-ground faulted feeder detection method, and hence formulates a schemeto reconstruct the outlet CT for existing 10kV substations that are equipped with onlytwo-phase CTs.With an in-depth investigation into the error causes of CT as the basis,this paper also elaborates on the operating principles and error causes of zero-sequencecurrent filtrator. As a further step, a wealth of experiments were undertaken to confirmits feasibility and to reveal its features .In addition, this paper also conducts a close examination on the existing digitalsimulation models of CT.Based on the data which is obtained in the lab experiments andby adopting the piece-wise linear method, this study establishes an ATP-EMTP modelfor zero-sequence current filtrator whose feasibility has been thereafter certified thoughlab experiments and realizes the digital simulation for zero-sequence current filtrator.