Study on New Method for Distributed Fault Location of Overhead Transmission Line

Fault location of overhead transmission line is one of the key technologies which guarantee the reliability of electric power system. In this study, the bandwidth of transient traveling wave was analyzed and the method of current transient traveling wave acquisition using Rogowski coil in the overhead transmission line is proposed. The corresponding relationships among transient traveling wave, refraction wave and reflection wave are discussed when detection devices are installed at different positions. The requirements for number and location of traveling wave detection devices are proposed. Furthermore, the location equation of distributed fault location system is established and the differentiation method of fault type and the false fault point is demonstrated based on the conclusion. The simulation of PSCAD indicates that the method of distributed fault location could eliminate the error brought by the uncertainty of traveling wave velocity, and the total error was small. It was expected to be widely applied in overhead transmission lines.