Study on accuracy traveling wave fault location method of overhead line — Cable hybrid line and its influencing factors

摘要

It has a complicated and variable feature of fault transient traveling wave in cable and overhead line hybrid transmission line. Theoretical analysis and simulation method have been used to study the propagation characteristics of fault transient traveling wave in cable and overhead line hybrid line. The principle of single line traveling wave method for hybrid line is expounded and the influence of phase inception angle, transition resistance, fault type, fault position was studied. Then, combined traveling wave fault location precision is researched. Meanwhile, it built the relationship between transient fault current and fault distance. The above factors have a significant impact on transient voltage and current wave. But they have no effect on the time required to reach the first wave of the traveling wave. The combined travelling wave fault location method has good accuracy for overhead line-cable hybrid transmission line.