Analysis of the Law of Refraction and Reflection of Fault Traveling Wave in Phase Domain

Through a large number of measured data, it is found that, the single-phase fault occurs on transmission line. the traveling wave of the fault phase is mainly composed of line-mode component, and the zero-mode component contained in it will not affect the detection and calibration of the fault traveling wave. However, the waveform of the two non-fault phase current waves is not exactly the same, and the wave shape is different from the fault phase. Therefore, the law of refraction and reflection of fault traveling wave in phase domain is analyzed, the expressions of fault initial traveling wave, fault point reflection wave and opposite bus reflection wave of non-fault phase current traveling wave are obtained. It is concluded that the reflection wave of the opposite bus in the non-fault phase current traveling wave is independent of the refraction and reflection of the transition impedance at the fault point. Based on this, the idea of fault location based on using fully the fault information contained in the non-fault phase and the comprehensive information of the three-phase current traveling wave is proposed, and the single-ended traveling wave reliable fault location of the transmission line is realized, and realizes the reliable distance measurement of the single end traveling wave of the transmission line.