An integrated approach for positional protection of transmission lines

The fast development in both microprocessor and transducer technologies has enabled fault detection techniques to be considered which were impractical in the past and encouraged interest in the utilization of fault generated transients for protection. This paper presents an integrated approach for high-speed protection of transmission lines. The technique uses a fault transient detector unit at the relaying point to capture fault generated high frequency transient signals contained in the primary currents. The decision to trip is based on communication and the relative arrival times of these high frequency components as they propagate through the system. Simulation studies of technique were carried out to examine the response to different power system and fault conditions.