Method for fault location to single-terminal traveling wave

A single-terminal traveling wave based fault locating method comprising steps operated by a main site and a plurality of electrical substations connected to the main site via a communication network, each of the electrical substations equipped with a traveling wave recording system, the method comprising:

• step (a):
• recording a waveform of a traveling wave signal of a line disturbance by a traveling wave device when the line disturbance occurs;
• step (b):
• performing a phase mode transformation on the waveform recorded by the step (a), so as to obtain components of line mode and zero mode of a fault initial traveling wave, and performing a wavelet transform to decompose the components of the line mode to obtain wavelet singularities in the waveform of the traveling wave;
• step (c):
• calculating a wavefront slope k of the components of the line mode of the fault initial traveling wave, wherein calculating the wavefront slope k of the components of the line mode of the fault initial traveling wave during the step (c) comprises:
• defining a wave head corresponding to a maximum value of a first mode which is detected after the wavelet transform of the step (b) as the disturbance initial traveling wave, and normalizing the components of the zero mode of the wave head such that the collected components of the zero mode of the wave head is amplified to a reference value, and rest of values are scaled up, wherein the reference value is 0.5 kA, and wherein the slope of the normalized wave head is computed by selecting points thereof, which is performed by selecting three sampling points from an initial point and linearly fitting the three selected sampling points with a least square method to obtain the slope k;
• step (d):
• computing a preliminary fault distance D according to the slope k computed in the step (c);
• step (e):
• confirming a fault point according to the preliminary fault distance and the wavelet singularities of the components of the line mode;
• and
• step (f):
• ending the steps.