A Traveling Wave Based Fault Locating System for HVDC Transmission Lines

The modern traveling wave based fault location principles for transmission lines are analyzed. In order to apply the traveling wave principles to HVDC transmission lines, the special technical problems are studied. Based on this, a fault locating system for HVDC transmission lines is developed. The system can support the type D and type A modern traveling wave principles simultaneously, and it is composed of three different parts: traveling wave data acquisition and processing system, communication network and PC based master station. In the system, the fault generated transients are induced from the ground leads of the overvoltage suppression capacitors of a HVDC line through special developed traveling wave couplers. The system was applied to 500 kV Ge Zhouba-Nanqiao (Shanghai) HVDC transmission line in China. Some field operation experiences are summarized, showing that the system has very high reliability and accuracy, and the maximum location error is about 3 km (not more than 0.3% of the total line length). Obviously, the application of the system is very successful, and the fault location problem since the line operation has finally been solved completely.