Transient based protection for transmission lines

This paper presents the application of 'transient-based protection' techniques to power transmission lines. A brief introduction to the history of development of relaying principles for transmission line protection, which outlines the background of the development, is given first. The advantages of transient-based protection schemes over the existing techniques are illustrated by the introduction of a number of novel techniques for transmission line protection. These are transient identification, transient based protection and adaptive transient reclosure techniques. The protection schemes provide a fast response, high accuracy, and are not affected by power frequency phenomena, such as fault path impedance, power swing and CT saturation.