Novel travelling wave fault location approach for overhead transmission lines
Dong Wang, Jinzhi Liu, Mengqian Hou
Abstract
Travelling wave fault location approach for overhead transmission line is widely applied in actual power grid, which has better fault location accuracy comparing with conventional power frequency data based method. However, travelling wave fault location approach is highly related to the frequency distortion phenomenon of travelling wave propagation velocity, which includes two parts: (i) the distortion caused by reflection and refraction phenomena of transformer substation and (ii) the attenuation caused by distributed resistance of transmission line. Therefore, aiming to improve the fault location accuracy, the paper contributes to two aspects: (i) the complete theoretical analysis of the distortion phenomenon of travelling wave signal and (ii) the improved travelling wave fault location approach considering distortion phenomenon. Eventually, based on PSCAD/EMTDC simulation tool, a typical 500 kV case study model is established to verify the fault location accuracy of proposed travelling wave fault location approach under the influences of fault type issue, fault location issue and grounding resistance issue.