直流配电网单极接地故障双端定位法

In this paper, a method to locate single-pole-to-ground fault in DC distribution network based on time domain Hilbert transform is proposed. It uses the characteristic that the transition resistance is pure resistance so that the instantaneous phase of mode current through the fault point is equal to that of the mode voltage to determine the fault position. In order to obtain the instantaneous phase of the fault voltage and current, this paper introduces sinusoidal representation of transient signal based on time domain Hilbert transform to deal with the data measured in each terminal. A two-terminal DC distribution network model is built based on PSCAD/EMTDC platform and the fault location algorithm is wrote through MATLAB software. The result shows that this method can accurately find the fault point within the whole DC line of DC distribution network, which needs short sampling window and has stable location results, and the ranging accuracy is not affected by transition resistance and fault location.