Longitudinal Differential Protection of Power Systems Transmission Lines Using Optical Waveguide

Abstract

This chapter describes using optical waveguide for communication between two relays on the opposite ends of the power systems transmission line (or transmission line). Transmission lines are a very important part of the power system. Because of that, relay protection must be fast and safe. Longitudinal differential protection satisfies these requirements. Pilot wire differential relays are commonly used for the protection of short lines. The existence of the pilot wires is a disadvantage. This protection is limited to lines of a few tens of kilometers. However, if optical protection ground wires (OPGWs) are used, instead of pilot wires, the length of the line ceases to be a limiting factor. The following sections tell more about constructions, assembly and utilization of the optical waveguides in differential protection. Also, the newest algorithms of this protection are listed.