Using Traveling-Wave Processes in the Development of Relay Protection for Overhead Lines (OHL)1

Abstract

The development of electric power systems has raised the requirements of relay protection — sensitivity, speed, and reliability of functioning—for all types of short circuits (SC). The raised requirements can be satisfied by using more complete damage information extracted during the traveling-wave stage of the transient process accompanying SC. The experience gained in working out directional traveling-wave relay protection is generalized and questions concerning the use of traveling-wave principles for developing smart relay protection networks with complex topology and devices making it possible to control power flows in ac lines are examined. An algorithm is proposed for tuning out external SC and determining the damaged phase by using modern methods of digital signal processing.